Accepted Manuscript Macrophages as a potential tumor-microenvironment target for noninvasive imaging of early response to anticancer therapy Qizhen Cao, Xinrui Yan, Kai Chen, Qian Huang, Marites P. Melancon, Gabriel Lopez, Zhen Cheng, Chun Li PII:
S0142-9612(17)30685-3
DOI:
10.1016/j.biomaterials.2017.10.036
Reference:
JBMT 18318
To appear in:
Biomaterials
Received Date: 13 April 2017 Revised Date:
30 September 2017
Accepted Date: 19 October 2017
Please cite this article as: Cao Q, Yan X, Chen K, Huang Q, Melancon MP, Lopez G, Cheng Z, Li C, Macrophages as a potential tumor-microenvironment target for noninvasive imaging of early response to anticancer therapy, Biomaterials (2017), doi: 10.1016/j.biomaterials.2017.10.036. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
1
Macrophages as a Potential Tumor-Microenvironment Target for Noninvasive
2
Imaging of Early Response to Anticancer Therapy
3 Qizhen Cao1, 2, Xinrui Yan2, Kai Chen2, Qian Huang1, Marites P. Melancon1, Gabriel
5
Lopez3, Zhen Cheng2*, and Chun Li1,4*
RI PT
4
6 7
1
8
Cancer Center, Houston, TX. United States
9
2
SC
Department of Cancer Systems Imaging, The University of Texas MD Anderson
Molecular Imaging Program at Stanford, Department of Radiology and Bio-X Program,
Stanford University School of Medicine, Stanford, CA. United States
11
3
12
Cancer Center, Houston, TX. United States
13
4
14
Biomedical Sciences at Houston, Houston, TX. United States
M AN U
10
Department of Experimental Therapeutics, The University of Texas MD Anderson
D
Experimental Therapeutics Program, The University of Texas Graduate School of
TE
15
*Corresponding Authors: Chun Li, Ph.D., Department of Cancer Systems Imaging,
17
1881 East Road-Unit 1907, The University of Texas MD Anderson Cancer Center,
18
Houston, Texas 77054, United States; Tel: 713-792-5182; Fax: 713-794-5456; E-mail:
19
[email protected].
20
Zhen Cheng, Ph.D., Molecular Imaging Program at Stanford, Department of Radiology
21
and Bio-X Program, Stanford University School of Medicine, 1201 Welch Road, Lucas
22
Expansion, P095, Stanford, CA 94305, United States; Tel: 650-723-7866; Fax: 650-736-
23
7925; E-mail:
[email protected].
AC C
EP
16
24 25
1
3
ACCEPTED MANUSCRIPT
Financial support: This work was supported in part by the John S. Dunn Foundation,
2
the Office of Science (BER), U.S. Department of Energy (DE-SC0008397), and the
3
Cancer Center Support Grant (P30CA016672) used for the Small Animal Imaging
4
Facility and the Research Animal Support Facility.
RI PT
1
5 6
Competing Interests: The authors have declared that no competing interest exists.
7 Word count: Abstract 200; Text: 4680
SC
8 9
Total number of figures: 8
M AN U
10 11 12 13
D
14
18 19 20 21 22
EP
17
AC C
16
TE
15
23 24 25 26 2
3
ACCEPTED MANUSCRIPT
1
Abstract As a result of therapy-induced apoptosis, peripheral blood monocytes are
3
recruited to tumors, where they become tumor-associated macrophages (TAMs). To
4
date, few studies have investigated noninvasive molecular imaging for assessment of
5
macrophage infiltration in response to therapy-induced apoptosis. Here, noninvasive
6
assessment of changes in tumor accumulation of TAMs was proposed as a new way to
7
measure early tumor response to anticancer therapy. Three different nanoparticles,
8
QD710-Dendron quantum dots (QD710-D), Ferumoxytol, and PG-Gd-NIR813, were
9
used for near-infrared fluorescence imaging, T2-weighted magnetic resonance imaging,
10
and dual optical/T1-weighted MR imaging, respectively, in the MDA-MB-435 tumor
11
model. Treatment with Abraxane induced tumor apoptosis and infiltrating macrophages.
12
In spite of markedly different physicochemical properties among the nanoparticles, in
13
vivo imaging revealed increased uptake of all three nanoparticles in Abraxane-treated
14
tumors compared with untreated tumors. Moreover, imaging visualized increased uptake
15
of QD710-D in MDA-MB-435 tumors but not in drug-resistant MDA-MB-435R tumors
16
grown in the mice treated with Abraxane. Our results suggest that infiltration of
17
macrophages due to chemotherapy-induced apoptosis was partially responsible for
18
increased nanoparticle uptake in treated tumors. Noninvasive imaging techniques in
19
conjunction with systemic administration of imageable nanoparticles that are taken up by
20
macrophages are a potentially useful tool for assessing early treatment response.
SC
M AN U
D
TE
EP
AC C
21
RI PT
2
22
Key words: Macrophage, Chemotherapy response, Nanoparticle, Optical Imaging,
23
Magnetic Resonance Imaging
24
3
3
ACCEPTED MANUSCRIPT
1
1. Introduction The tumor microenvironment contributes to tumor initiation, progression,
3
metastasis, and resistance to therapy. Macrophages are found in all tissue types
4
including tumors. Their origin is bone marrow with an intermediary step in their
5
continuum of differentiation as peripheral blood monocytes. Young monocytes are
6
capable of inducing inflammation due to their ability to secrete various cytokines, as they
7
mature/differentiate in tissues, they adjust to the environment. In tumors, tumor-
8
associated macrophages (TAMs) primarily exhibit the M2 phenotype. Referred to as
9
alternatively activated macrophages, these TAMs are believed to contribute to tumor
10
growth and progression and to promote tumor cell survival, proliferation, and
11
dissemination [1, 2]. In many cancers, high macrophage infiltration correlates with poor
12
outcome [3-5].
M AN U
SC
RI PT
2
Historically, studies examining tissue and cellular responses to chemotherapy
14
and radiation therapy predominantly focused on the eradication of proliferating malignant
15
cells. However, increasing evidence suggests that these treatments also significantly
16
alter the tumor microenvironment, particularly with respect to tumor-infiltrating immune
17
cells, including TAMs. Most chemotherapeutic agents kill cancer cells by inducing
18
apoptosis [6-8]. Recent studies have shown that cells undergoing apoptosis express
19
specific “eat me” signals (e.g. phosphatidylserine) that facilitate recognition and ingestion
20
by macrophages [9, 10]. As a result, both chemotherapy and radiation therapy have
21
been shown to result in tumor infiltration of macrophages [11-14].
TE
EP
AC C
22
D
13
Given the recruitment of TAMs in response to apoptosis, assessment of TAMs
23
has been considered as a new way to measure early tumor response to anticancer
24
therapy.
25
immunohistochemical and histological examination of excised tumor specimens. Such
26
techniques, however, are limited in the assessment of TAM infiltration over time and
At
present,
the
gold
standard
4
for
the
assessment
of
TAMs
is
3
ACCEPTED MANUSCRIPT
1
cannot be used when biopsy samples are not available. We hypothesized that TAMs could be imaged noninvasively to monitor early
3
tumor response to anticancer therapy. Specifically, since TAMs are phagocytes and very
4
efficient at internalizing particles, we hypothesized that TAMs could be imaged by using
5
nanoparticles that would be readily phagocytosed or internalized. To test this hypothesis,
6
we used three different nanoparticles with markedly different physicochemical properties
7
and had previously been evaluated for selective visualization of TAMs in cancer: QD710-
8
Dendron quantum dots (QD710-D), Ferumoxytol, and PG-Gd-NIR813 (Fig. 1) [15-17].
9
QD710-D is a new type of dendron-coated InP/ZnS core/shell QD. The core size of
10
QD710-D is about 5 nm in diameter, with a hydrodynamic diameter of about 11.8 nm.
11
QD710-D emit a fluorescent signal in the near-infrared (NIR) region, have high chemical
12
stability and photostability in biological media, and exhibit low systemic toxicity [18].
13
Ferumoxytol is an ultrasmall superparamagnetic iron oxide nanoparticle approved by the
14
US Food and Drug Administration (FDA) as an iron supplement for intravenous
15
treatment of iron deficiency in patients [19-21]. Ferumoxytol is composed of
16
superparamagnetic iron oxide and polyglucose sorbitol carboxymethyl ether coated
17
on its surface. It has a mean hydrodynamic diameter of 30 nm and displays a prolonged
18
blood pool circulation time [22-24]. Ferumoxytol has also been evaluated as a contrast
19
agent for T2-weighted magnetic resonance imaging (MRI) [25-28]. PG-Gd-NIR813 is a
20
dual magneto-optical imaging probe consisting of poly(L-glutamic-acid) (PG) conjugated
21
with DTPA-Gd and a NIR fluorescence (NIRF) dye NIR813. PG-Gd has been shown to
22
be an excellent blood-pool MRI agent in both mice and rhesus monkeys for T1-weighted
23
MR imaging [29]. PG-Gd-NIR813 has also been shown to accumulate in macrophages
24
of solid tumors [17, 30].
AC C
EP
TE
D
M AN U
SC
RI PT
2
25
5
3
ACCEPTED MANUSCRIPT
1
2. Materials and methods
2
2.1. Chemicals and reagents Abraxane (10% paclitaxel and 90% human serum albumin) was purchased from
4
Abraxis Oncology (Bridgewater, NJ). The kits for the MTS (3-(4,5-dimethylthiazol-2-yl)-5-
5
(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) cell proliferation assay and
6
terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were
7
purchased from Promega (Madison, WI). QD710-Dendron quantum dots (QD710-D) was
8
provided by NN-Labs (Fayetteville, AR). Ferumoxytol (Feraheme) was purchased from
9
AMAG Pharmaceuticals Inc. (Waltham, MA). PG-Gd-NIR813 was synthesized as
10
reported before [17]. Rat anti-mouse CD169 antibody was purchased from AbD Serotec
11
(Raleigh, NC). FITC-labeled rat anti-mouse CD11b antibody was purchased from BD
12
Biosciences (San Jose, CA). Alexa Fluor 594-conjugated goat anti-rat secondary
13
antibody was purchased from Invitrogen Molecular Probes (Grand Island, NY). Mounting
14
medium with DAPI was purchased from Vector Laboratories (Burlingame, CA). FITC-
15
labeled anti-CD45, PE-labeled anti-CD11b, eFluor660-labeled anti-CD169, Percp.Cy5.5-
16
labeled anti-F4/80, and fixable viability dye eFluor780 used for flow cytometry
17
experiments were purchased from eBioscience (San Diego, CA). Isoflurane was
18
purchased from Abbott Laboratories (Abbott Park, IN). D-luciferin was purchased from
19
Biosynth International, Inc. (Itasca, IL).
21 22
SC
M AN U
D
TE
EP
AC C
20
RI PT
3
2.2. Cell lines
Human MDA-MB-435 (M4A4) breast carcinoma cells were purchased from the
23
American Type Culture Collection (Manassas, VA) and were reconfirmed with Short
24
Tandem Repeat (STR) DNA fingerprinting method by the Characterized Cell Line Core
25
Facility of The University of Texas MD Anderson Cancer Center when the cells were
6
3
ACCEPTED MANUSCRIPT
1
used in this study. The MDA-MB-435 cells were maintained in Leibovitz's L-15 medium
2
(Invitrogen) supplemented with 10% fetal bovine serum at 37C. The resistant subline MDA-MB-435R was generated in our laboratory by
4
continuous exposure of MDA-MB-435 cells to paclitaxel. Briefly, the parent MDA-MB-435
5
cells were exposed to increasing concentrations of paclitaxel, from 1 nM to 25 nM, and
6
the cells were maintained in continuous culture with 25 nM paclitaxel for 30 days.
RI PT
3
Mouse RAW264.7 macrophages were purchased from American Type Culture
8
Collection and maintained in Dulbecco's modified Eagle's medium (Invitrogen)
9
supplemented with 10% fetal bovine serum at 37C and 5% CO2. The cells were used
M AN U
10
SC
7
within 6 months after receipt.
11 12
2.3. Tracking of cellular uptake of QD710-D in vitro
RAW264.7 murine macrophages and MDA-MB-435 human breast cancer cells
14
(1×105 cells for each cell line) were separately seeded in cell culture petri dishes for 24 h.
15
Then, QD710-D was added (final concentration, 1 nM), and cells were incubated for 1 h
16
or 20 h. After the washing steps, the cells were stained with FITC-labeled rat anti-mouse
17
CD11b antibody. All fluorescence images were acquired under the same conditions and
18
displayed under the same color scale using a Zeiss fluorescence microscope (Zeiss Axio
19
Observer.Zl, Carl Zeiss MicroImaging GmbH, Gȍttingen, Germany).
21 22
TE
EP
AC C
20
D
13
2.4. Tracking of cellular uptake of Ferumoxytol by Prussian blue staining RAW264.7 murine macrophages and MDA-MB-435 human breast cancer cells
23
(1×105 cells for each cell line) were separately seeded in cell culture petri dishes for 24 h.
24
Then, Ferumoxytol was added (final concentration, 200 µg/ml), and cells were incubated
25
for 1 h or 24 h. After the washing steps, the cells were fixed with a 1% paraformaldehyde
7
3
ACCEPTED MANUSCRIPT
1
and stained with Prussian blue staining kit (Ocean Nanotech, CA). Images were
2
acquired by a Zeiss microscope.
3 2.5. Tracking of cellular uptake of PG-Gd-NIR813 by T1-weighted MRI
RI PT
4
RAW264.7 murine macrophages and MDA-MB-435 human breast cancer cells
6
(5×106 cells for each cell line) were separately seeded in cell culture dishes for 24 h.
7
Then, PG-Gd-NIR813 was added (final concentration, 25 µM Gd) [31], and cells were
8
incubated for 1 h or 24 h. After the washing steps, the cells were collected in 200 µl
9
Eppendorf tubes and mixed with 1% Agarose (BD, Franklin lakes, NJ). After the agarose
10
solidified, T1-weighted MRI was acquired on a 7.0-Tesla Bruker Biospec scanner
11
(Fremont, CA).
M AN U
SC
5
12 13
2.6. Animal models
All animal experiments were performed in compliance with the guidelines for the
15
care and use of research animals established by Stanford University’s Animal Studies
16
Committee and The University of Texas MD Anderson Cancer Center. Female athymic
17
nude mice (nu/nu) were purchased from Harlan (Indianapolis, IN) at 6–8 weeks of age.
18
MDA-MB-435 human breast cancer cells were harvested and washed with sterile
19
phosphate-buffered saline (PBS), suspended and adjusted the cell concentration to
20
5×107 cells/ml in PBS. Viable cells (5×106) in PBS (100 μl) were inoculated into the
21
mammary fat pad or subcutaneously into the shoulder. Tumor growth was monitored by
22
digital caliper with measuring perpendicular diameters of the tumor. The tumor volume
23
was estimated by the following formula: tumor volume = a × (b2)/2, where a and b are
24
the tumor length and width, respectively, in millimeters.
AC C
EP
TE
D
14
25 26
2.7. Treatment of mice with MDA-MB-435 breast tumors 8
3
ACCEPTED MANUSCRIPT When mice bearing MDA-MB-435 tumors grew around 100–150 mm3, mice were
2
randomly divided into two groups (n = 8 per group). Mice in group 1 were not treated and
3
served as a control. Mice in group 2 received 5 daily intravenous injections of Abraxane
4
at an equivalent paclitaxel dose of 30 mg/kg per injection. The mouse body weight and
5
tumor volume were measured every 3 days before animals were euthanized.
RI PT
1
In a separate study, MDA-MB-435 tumor-bearing mice were randomly divided
7
into two groups (n = 5 per group). Mice in group 1 were not treated and served as a
8
control. Mice in group 2 received a single intravenous injection of Abraxane at an
9
equivalent paclitaxel dose of 30 mg/kg. The mouse body weight and tumor volume were measured every 3 days before animals were euthanized.
M AN U
10
SC
6
11 12
2.8. In vivo NIRF optical imaging with QD710-D
Mice bearing subcutaneous MDA-MB-435 tumors were used in the in vivo
14
imaging studies with QD710-D. Mice were either not treated or treated with an
15
intravenous injection of Abraxane at an equivalent paclitaxel dose of 30 mg/kg (n =
16
3/group). Three days later, mice in the untreated control and treatment groups were
17
anesthetized with 1%–2% isoflurane in O2 and injected intravenously with QD710-D (200
18
pmol/mouse). Two-dimensional NIRF images were acquired at various time points after
19
injection using a Xenogen IVIS-200 optical in vivo imaging system (Caliper Life Sciences,
20
Hopkinton, MA).
TE
EP
AC C
21
D
13
To compare response to treatment between chemosensitive and chemoresistant
22
tumor cells, each mouse was inoculated in the mammary fat pads with the parent MDA-
23
MB-435 cells on one side and the resistant MDA-MB-435R cells on the contralateral side.
24
When the tumor size reached 150 mm3, mice were either not treated or treated with an
25
intravenously injection of Abraxane at an equivalent paclitaxel dose of 30 mg/kg. Three
9
3
ACCEPTED MANUSCRIPT
1
days later, QD710-D were injected intravenously and NIRF images acquired as
2
described in the preceding paragraph.
3 2.9. In vivo T2-weighted MR imaging with Ferumoxytol
RI PT
4
Mice bearing MDA-MB-435 tumors were either not treated or treated with
6
Abraxane at a single equivalent paclitaxel dose of 30 mg/kg. Three days later,
7
Ferumoxytol was injected through the tail vein (50 mg equivalent Fe/kg of mouse). T2-
8
weighted fast spin-echo images were acquired on a 7.0-Tesla Bruker Biospec scanner
9
before and at 1 h and 24 h after contrast agent injection, with the following parameters:
10
TE, 38 ms; TR, 1800 ms; thickness, 0.75 mm; FOV, 4 × 3 cm; NEX , 4.0; Matrix, 256 ×
11
192; and echo train length (RATE factor), 8.
M AN U
SC
5
12 13
2.10. In vivo T1-weighted MR/NIRF optical imaging with PG-Gd-NIR813 Three days after Abraxane treatment (single dose, 30 mg/kg equivalent
15
paclitaxel), PG-Gd-NIR813 was injected through the tail vein (0.2 mmol Gd/kg, 14.4
16
µmol NIR813/kg of mouse). Mice in Abraxane-treated and untreated groups were
17
imaged at multiple time points using the IVIS-200 system, and T1-weighted MR imaging.
18
T1-weighted images were acquired on a 7.0-Tesla Bruker Biospec scanner (Fremont,
19
CA) before and at 1 h, 24 h, and 48 h after contrast agent injection. The following
20
acquisition parameters were used: TE (echo time), 9.5 ms; TR (repetition time), 900 ms;
21
thickness, 0.75 mm; FOV (field of view), 4 × 3 cm; NEX (number of excitations), 2; and
22
Matrix, 256 × 192.
AC C
EP
TE
D
14
23 24
2.11. TUNEL staining
25
Tissue slices (10 μm thick) were stained for TUNEL according to the
26
manufacturer-provided protocol. After staining, slides were mounted with DAPI10
3
ACCEPTED MANUSCRIPT
containing medium, and fluorescent images were obtained under a fluorescence
2
microscope. For the double staining of TUNEL and macrophage marker CD169 on
3
tumor tissue, slides were blocked with 10% goat serum in PBS for 15 min at room
4
temperature after TUNEL staining and then incubated with rat anti-mouse CD169
5
antibody (1:100) for 1 h at room temperature. After being washed three times for 5 min
6
with PBS, slides were incubated with Alexa Fluor 594-conjugated goat anti-rat
7
secondary antibody (1:2000) for 0.5 h at room temperature, and sections were washed
8
with PBS three times for 5 min. After staining, slides were mounted with Vectashield
9
DAPI-containing mounting medium and examined under a fluorescence microscope.
SC
RI PT
1
11
M AN U
10 2.12. Flow cytometric analysis
To prepare single-cell suspensions for flow cytometry, harvested tumor tissues
13
were cut into small fragments and digested with 0.25% collagenase type I (Life
14
Technologies), 0.02% hyaluronidase (Sigma Roche) and 0.01% DNase I (Sigma Roche)
15
in RPMI-1640 containing 10% FBS for 1 h at 37°C in water bath while shaking. Next, cell
16
suspensions were passed through 100-micron cell strainers to remove aggregates,
17
single-cell suspensions were counted, and viability was determined by trypan blue dye.
18
Single-cell suspensions were incubated with FITC-labeled CD45, PE-labeled CD11b,
19
eFluor660-labeled CD169, and fixable viability dye eFluor780 for 30 min on ice. Cells
20
were washed twice with PBS, and then fixed with 1% paraformaldehyde. These tumor
21
tissue single-cell samples were detected with LSR Fortessa X-20 Analyzer (BD
22
Biosciences), and the data were analyzed with FlowJo software (Treestar).
AC C
EP
TE
D
12
23 24 25 26
2.13. Statistical analysis Statistical significance was determined by one-way ANOVA. P values < 0.05 were considered statistically significant. 11
3
ACCEPTED MANUSCRIPT
1
3. Results
2
3.1. Abraxane treatment delayed tumor growth and caused apoptotic cell death in MDA-
3
MB-435 tumors Five daily doses of Abraxane at an equivalent paclitaxel dose of 30 mg/kg per
5
dose significantly delayed the growth of orthotopic MDA-MB-435 breast tumors
6
compared with the growth of the untreated tumors at each time point from days 5 to 22
7
after initiation of treatment (P < 0.001 for each time point) (Fig. 2A). A single dose of
8
Abraxane at an equivalent paclitaxel dose of 30 mg/kg also significantly delayed tumor
9
growth compared with the growth of the untreated tumors (P < 0.05 for each time point
SC
from days 4 to 16 after injection) (Fig. 2B).
M AN U
10
RI PT
4
TUNEL assay showed that a single dose of Abraxane at 30 mg/kg markedly
12
increased the apoptotic response in MDA-MB-435 tumors at 5 days after treatment
13
compared with the untreated control (Fig. 2C). The apoptotic cells showed nuclear
14
shrinkage, nuclear fragmentation, and chromatin condensation (Supplementary Fig.
15
S1). To evaluate whether Abraxane-induced apoptosis correlated with the number of
16
infiltrating TAMs, MDA-MB-435 tumors from untreated and single-dose Abraxane-treated
17
mice were double-stained for TUNEL (green) and activated macrophage marker CD169
18
(red). As shown in Figure 2C, most TAMs were distributed in the tumor region with
19
patches of apoptotic cells. On the basis of these results, the single-dose treatment
20
regimen was used in the subsequent imaging studies.
22
TE
EP
AC C
21
D
11
3.2. Macrophages but not tumor cells internalized nanoparticles in vitro
23
After incubation with QD710-D nanoparticles for 20 h, RAW264.7 mouse
24
macrophages exhibited a strong fluorescent signal. In contrast, MDA-MB-435 breast
25
cancer cells did not take up QD710-D under the same conditions (Fig. 3A). Similar data
26
were observed after 1 h of incubation (data not shown). Moreover, RAW264.7 12
3
ACCEPTED MANUSCRIPT
macrophages but not MDA-MB-435 cells showed uptake of Ferumoxytol at 1 h and 24 h
2
after incubation (Fig. 3B). T1-weighted MRI showed a significant increase in the MR
3
signal for RAW264.7 macrophages incubated with PG-Gd-NIR813 for 1 h and 24 h,
4
whereas no change in MR signal was observed for MDA-MB-435 breast cancer cells
5
incubated with PG-Gd-NIR813 for the same time periods (Fig. 3C, 3D).
RI PT
1
To address whether different macrophage phenotypes could take up
7
nanoparticles, TAMs isolated from MDA-MB-435 tumor tissues [32] were exposed to
8
interferon-γ / lipopolysaccharide to induce M1-polarized TAMs, and to interleukin-4 to
9
induce M2-polarized TAMs. Both M1 and M2 TAMs effectively took up Ferumoxytol
10
nanoparticles (Supplementary Fig. S2). Similarly, both M1- and M2-polarized bone
11
marrow-derived
12
nanoparticles (Supplementary Fig. S3). Taken together, macrophages could efficiently
13
take up nanoparticles independent of their functional states.
macrophages
(BMDMs)
effectively
phagocytosed
Ferumoxytol
D
14
M AN U
SC
6
3.3. Noninvasive optical imaging and MRI indicated increased uptake of nanoparticles in
16
tumors of Abraxane-treated mice
TE
15
Figure 4A shows representative NIRF optical images of mice at 4 h after
18
intravenous injection of QD710-D. The uptake of QD710-D in MDA-MB-435 tumors was
19
much higher in mice treated with Abraxane than in untreated mice. Quantitative analysis
20
of fluorescence signal intensity confirmed that MDA-MB-435 tumors from Abraxane-
21
treated mice had significantly higher QD710-D uptake than did MDA-MB-435 tumors
22
from untreated mice at all-time points analyzed after QDs injection (P < 0.01) (Fig. 4B).
AC C
EP
17
23
Ex vivo NIRF optical imaging performed 4 h after injection showed similar uptake
24
of QD710-D in untreated and treated mice for all major organs but significantly higher
25
uptake of QD710-D in tumors from Abraxane-treated mice than in tumors from untreated
26
mice (Supplementary Fig. S4). In both treated and untreated mice, QD710-D exhibited 13
3
ACCEPTED MANUSCRIPT
relatively high uptake in the liver, kidney, skin, and tumor. Interestingly, the uptake of
2
QD710-D in the spleen was relatively low. A previous study showed that QD710-D could
3
be cleared through the renal system, which helps explain the relatively high uptake of
4
the nanoparticles observed in the kidney [18]. The optical signal from the skin could be
5
attributed to nonspecific accumulation of QD710-D nanoparticles in the skin, similar to
6
what was observed by Sykes et al. [33] with another quantum dot nanoparticle system.
RI PT
1
We next investigated whether Ferumoxytol, a T2-MRI contrast agent, could also
8
detect changes after Abraxane treatment. In Abraxane-treated mice, all MDA-MB-435
9
tumors showed significant enhancement on T2-weighted MR imaging at 1 h and 24 h
10
after injection of Ferumoxytol compared with images acquired before the injection of the
11
contrast agent. However, in untreated mice, MDA-MB-435 tumors did not show
12
significant enhancement after Ferumoxytol injection compared with images acquired
13
before Ferumoxytol (Fig. 4C). Significantly lower T2 signal intensity was observed in
14
tumors of Abraxane-treated mice than in tumors from untreated control mice at either 1 h
15
or 24 h after Ferumoxytol injection (Fig. 4D).
TE
D
M AN U
SC
7
The dual-modality optical/MR imaging probe PG-Gd-NIR813 was used to
17
evaluate the macrophage infiltration and response to treatment. NIRF optical imaging of
18
mice with MDA-MB-435 tumors showed that PG-Gd-NIR813 had higher uptake in
19
Abraxane-treated tumors than in untreated tumors at 48 h after contrast agent injection
20
(Fig. 5A). Quantitative analysis of images showed a significantly higher tumor-to-muscle
21
fluorescence intensity ratio in the Abraxane-treated mice (4.99 ± 0.66) than in the
22
untreated mice (3.03 ± 0.06) at 48 h after contrast agent injection (P < 0.01) (Fig. 5B).
23
These data were confirmed by ex vivo NIRF optical imaging of major organs and tumors
24
taken from both untreated and Abraxane-treated mice at 48 h after intravenous injection
25
of PG-Gd-NIR813 (Supplementary Fig. S5A). Quantitative analysis showed that there
26
was significantly higher uptake of PG-Gd-NIR813 in Abraxane-treated tumors than in
AC C
EP
16
14
3
ACCEPTED MANUSCRIPT
untreated tumors (Supplementary Fig. S5B). T1-weighted MR images with PG-Gd-
2
NIR813 showed a distribution pattern similar to that observed with optical imaging (Fig.
3
5C). Before (prescan) and at 1 h after contrast agent injection, no difference was seen in
4
tumor T1-weighted signal intensity between tumors from untreated and Abraxane-
5
treated mice. However, at 24 h and 48 h after contrast agent injection, signal intensity
6
was significantly higher in tumors from Abraxane-treated mice than in tumors from
7
untreated mice (P < 0.05) (Fig. 5D).
RI PT
1
10
3.4. Abraxane treatment resulted in increased infiltration of macrophages in MDA-MB435 tumors
M AN U
9
SC
8
Tumor tissues staining with CD11b antibody showed increased infiltration of
12
leukocytes into tumors of Abraxane-treated mice (Fig. 6A). Moreover, some CD11b-
13
positive cells co-localized with fluorescent signal from QD710-D in tumor tissue (Fig. 6B).
14
Since macrophages possess the phagocytic function in CD11b+ cell population, these
15
data suggest that QD710-D was taken up by TAMs.
TE
D
11
To further confirm TAMs uptaking of nanoparticles, tumors from both Abraxane-
17
treated and untreated mice that received intravenous injection of QD710-D were
18
analyzed by flow cytometry. Results showed that there was significantly higher CD45+
19
myeloid cells infiltrated into tumor tissue of Abraxane-treated MDA-MB435 tumors than
20
tumors from the untreated mice (Fig. 6C, 6D) (P < 0.001) and that there was significantly
21
higher infiltration of CD45+CD169+ macrophages in Abraxane-treated tumors than in
22
tumors from the untreated group (Fig. 6C, 6E) (P < 0.01). Moreover, QD710-D co-
23
localized with CD169+ macrophages in the tumors from both treated and untreated
24
groups: 96.5% ± 2.7% and 98.2% ± 0.5% of QDs were co-localized to CD169+ cells in
25
the treated and untreated tumors, respectively (Fig. 6C, 6F), suggesting that QDs in the
26
tumors were mostly taken up by TAMs.
AC C
EP
16
15
3
ACCEPTED MANUSCRIPT
1 3.5. Abraxane treatment resulted in more macrophage infiltration and higher
3
nanoparticle accumulation in drug-sensitive MDA-MB-435 tumors than in drug-resistant
4
MDA-MB-435R tumors
RI PT
2
5
In vitro cell proliferation study showed that MDA-MB-435R cells were more
6
resistant to paclitaxel treatment than were parental MDA-MB-435 cells after 72 h and 96
7
h of continuous incubation (Supplementary Fig. S6).
Flow cytometry analysis of parent MDA-MB-435 and resistant MDA-MB-435R
9
tumors grown in female nude mice showed that there was significantly increased cell
10
death in the parent MDA-MB-435 tumors treated with Abraxane than in untreated tumors
11
(Fig. 7A, 7C) (P < 0.05). However, treatment with Abraxane at the same dose did not
12
cause cell death in the resistant MDA-MB-435R tumors (Fig. 7B, 7C). In addition, for
13
MDA-MB-435 tumors, significantly higher CD45+ myeloid cells, CD11b+ leukocytes, and
14
F4/80+ macrophages infiltrated into the tumor tissue of Abraxane-treated mice than into
15
the tumor tissue of untreated mice (Fig. 7A, 7D) (P < 0.001). In contrast, for resistant
16
MDA-MB-435R tumors, there were significantly lower CD45+ myeloid cell and CD11b+
17
leukocyte subpopulations in tumors from Abraxane-treated mice than in tumors from
18
untreated mice (Fig. 7B, 7D) (P < 0.05). There were no differences in population of
19
F4/80+ macrophages between MDA-MB-435R tumors of Abraxane-treated mice and
20
untreated mice (Fig. 7D). Moreover, there were significantly higher CD45+ myeloid cells,
21
CD11b+ leukocytes, and F4/80+ macrophages in Abraxane- sensitive MDA-MB-435–
22
tumors than in Abraxane-resistantMDA-MB-435R tumors (Fig. 7D) (P < 0.001). These
23
results indicated that there were more macrophages infiltrating into chemotherapy-
24
sensitive MDA-MB-435 tumors than into chemotherapy-resistant MDA-MB-435R tumors.
25
In vivo optical images acquired after injection of QD710-D showed that after
26
Abraxane treatment, MDA-MB-435 tumors but not resistant MDA-MB-435R tumors
AC C
EP
TE
D
M AN U
SC
8
16
3
ACCEPTED MANUSCRIPT
displayed a strong fluorescence signal (Fig. 8A). Quantitative analysis of signal intensity
2
confirmed that in MDA-MB-435 tumors, the intensity of the fluorescence signal from
3
QD710-D was significantly greater in tumors from Abraxane-treated mice than in tumors
4
from untreated mice (P < 0.01). However, in resistant MDA-MB-435R tumors, there were
5
no differences between Abraxane-treated and untreated tumors (Fig. 8B).
RI PT
1
6 7
4. Discussion
In this study, we tested the hypothesis that tumor infiltration by macrophages in
9
response to therapy-induced apoptosis can be monitored with noninvasive imaging of
10
nanoparticles that are readily taken up by macrophages. Using noninvasive optical
11
imaging and MRI, we found that three different types of nanoparticles with different
12
chemical compositions showed significantly higher uptake in Abraxane-treated tumors
13
than in untreated tumors (Fig. 4, 5). Several lines of evidence support the idea that
14
these intensity enhancements can be attributed, at least in part, to increased infiltration
15
of TAMs to tumors after therapy. First, in vitro studies showed that all three types of
16
nanoparticles were taken up by macrophages but not by MDA-MB-435 cells (Fig. 3).
17
Second, ex vivo studies of macrophage immunofluorescence staining of tumor tissues
18
and flow cytometry of single-cell suspensions from dissected tumor tissues confirmed
19
increased infiltration of CD11b+ and CD169+ macrophages in the tumors responding to
20
Abraxane therapy, and QDs were almost completely co-localized with CD169+
21
macrophages in both treated and untreated tumors (Fig. 6). Third, treatment-induced
22
apoptosis coincided with increased infiltration of macrophages, which were co-localized
23
with apoptotic cells (Fig. 2). Finally, only the Abraxane-sensitive MDA-MB-435 tumors
24
but not the Abraxane-resistant MDA-MB-435R tumors showed increased tumor uptake
25
of QD710-D QDs after Abraxane treatment (Fig. 8). Flow cytometry analysis of single-
26
cell suspensions from dissected tumors confirmed significantly increased population of
AC C
EP
TE
D
M AN U
SC
8
17
3
ACCEPTED MANUSCRIPT F4/80+ macrophages in the MDA-MB-435 tumors but not in the MDA-MB-435R tumors
2
between Abraxane-treated mice and untreated control (Fig. 7). Taken together, these
3
data support the idea that chemotherapy-induced apoptosis resulted in increased tumor
4
infiltration by macrophages, which are known to assist in the clearance of cellular debris.
5
Change in the population of TAMs that had taken up nanoparticles was then visualized
6
after therapy. These data indicate that it is feasible to monitor changes of tumor
7
microenvironment by using imageable nanoparticles as a surrogate for the assessment
8
of early apoptotic response.
SC
RI PT
1
Macrophages originate from blood monocytes, which differentiate into two
10
distinct subtypes: classic M1 and alternative M2 macrophages. TAMs resemble M2-
11
macrophages in that they mostly exhibit pro-tumoral functions [34-36]. Most of the
12
studies to date have indicated a strong correlation between the presence of TAMs and
13
poor outcome [4, 37-39]. Since both M1 and M2 macrophages possess a phagocytic
14
function, imageable nanoparticles used in the current study could not distinguish M1 and
15
M2 subtypes. However, since both M1- and M2-polarized TAMs and BMDMs effectively
16
took up Ferumoxytol nanoparticles (Supplemental Fig. S2&S3), we conclude that the
17
signal enhancement observed in our imaging studies was mainly a result of increased
18
numbers of TAMs rather than increased uptake efficiency by each macrophage cell. Our
19
findings indicate that a large influx of macrophages into the tumor could be seen early
20
after initiation of treatment. However, the exact nature of these newly recruited
21
macrophages remains to be defined. Also, the potential impact of these newly recruited
22
TAMs on long-term tumor regression/progression after therapy is not known. If an
23
increase in newly infiltrated TAMs correlates with poor outcome, it would be beneficial to
24
test the combination of TAM-ablation therapy and apoptosis-inducing agents. In such a
25
scenario, noninvasive imaging studies that reveal the timing and extent of tumor
AC C
EP
TE
D
M AN U
9
18
3
ACCEPTED MANUSCRIPT
1
infiltration of macrophages would be valuable in guiding the planning of an optimized
2
treatment schedule. A limitation of this study is that we did not examine the possible role of changes
4
in microvessel density (MVD) resulting from chemotherapy that may affect tumor uptake
5
of nanoparticles. Previous studies have shown that tumors with high angiogenic activity
6
(i.e. higher MVD) had higher intratumoral deposition of nanoparticles [40, 41].
7
Nevertheless, we note that in the MDA-MB-435 model, treatment with paclitaxel in fact
8
decreased tumor MVD [42, 43]. These findings argue against the possibility that
9
increased tumor uptake of nanoparticles was a result of increased angiogenic blood
10
vessels, and further support the notion that increased number of TAMs infiltrating tumor
11
bed was a main factor of increased tumor uptake of nanoparticles after paclitaxel
12
chemotherapy. Clearly, further studies are needed to clarify the relative roles of
13
apoptosis/TAMs and altered blood perfusion on increased imaging signals from
14
nanoparticles after chemotherapy. Because most nanoparticles have high background
15
signal in the liver, the method reported in this work might not be suitable for imaging
16
response of liver cancer or liver metastasis to treatments. Another limitation of this study
17
is that we did not examine uptake of nanoparticles in human tumor-associated
18
macrophages from human tumor tissues. Availability of such data should further
19
strengthen the translational potential of nanoparticle-based imaging agents.
SC
M AN U
D
TE
EP
AC C
20
RI PT
3
To facilitate deeper understanding of the complex roles of macrophages in
21
cancer progression and response to therapy, it is necessary to develop and validate
22
clinically translatable noninvasive imaging techniques for tracking the migration, tumor
23
homing capabilities, and fate of macrophages [44]. Several imaging probes have been
24
evaluated for selective visualization of TAMs in cancer, including superparamagnetic
25
iron oxide nanoparticles for T2-weighted MR imaging [25], gadolinium-based contrast
26
agents for T1-weighted MR imaging [17], NIRF probes for optical imaging [15, 45, 46], 19
3
ACCEPTED MANUSCRIPT
and radiotracers for positron emission tomography imaging
[47]. Appropriate
2
physicochemical properties of nanoparticles promoted macrophage uptake and befitted
3
as imageable nanoparticles [48-50]. The identification of a particular nanoparticle system
4
for further development for clinical use is likely governed by a number of economic and
5
regulatory issues and requires further improvements in sensitivity and selectivity [51].
RI PT
1
Monitoring therapy response using imaging methods is an important component
7
of personalized medicine. Positron emission tomography (PET) and single photon
8
emission computed tomography (SPECT) with appropriate radiotracers can be used to
9
assess changes associated with metabolic activity (e.g.,18F-FDG [52]), cell proliferation
SC
6
18
(e.g.,
11
resonance imaging (MRI) that measures water relaxation, diffusion, and exchange can
12
provide data related to the breakdown of macromolecules, loss of membrane integrity,
13
change in cell size, and change in water content during cell death [56, 57]. Dynamic
14
contrast-enhanced ultrasound (DCE-US) has been proposed for monitoring therapy-
15
induced changes in blood perfusion [58]. Quantitative ultrasound (QUS) has been
16
demonstrated to be capable of detecting cell death [59]. Imaging apoptotic cell death
17
with visualizable nanoparticles on the basis of increased tumor infiltration of
18
macrophages would be a useful addition to the toolbox of imaging techniques for early
19
assessment of treatment response.
21 22
D
TE
EP
AC C
20
F-FLT [53]), tumor hypoxia [54], and other functional measures [55]. Magnetic
M AN U
10
5. Conclusion
Tumor infiltrating macrophage changes due to chemotherapy-induced apoptosis
23
can partly reflect the tumor early response to therapy, which can be monitored by non-
24
invasive molecular imaging with suitable nanoparticles.
25 26 20
3
ACCEPTED MANUSCRIPT
1
Acknowledgments We thank Stephanie Deming and Tamara Locke for editing the article. This work
3
was supported in part by the John S. Dunn Foundation (to CL), U.S. Department of
4
Energy (DE-SC0008397) (to ZC), and the Cancer Center Support Grant (P30CA016672)
5
for support of the animal studies. We thank the support from Department of Veterinary
6
Medicine and Surgery, Small Animal Imaging Facility, and Flow Cytometry & Cellular
7
Imaging Core Facility at UT MD Anderson Cancer Center.
AC C
EP
TE
D
M AN U
SC
8
RI PT
2
21
3
ACCEPTED MANUSCRIPT
References
2
[1] J.W. Pollard, Tumour-educated macrophages promote tumour progression and
3
metastasis, Nat. Rev. Cancer 4(1) (2004) 71-8.
4
[2] J.E. Talmadge, M. Donkor, E. Scholar, Inflammatory cell infiltration of tumors: Jekyll
5
or Hyde, Cancer Metastasis Rev. 26(3-4) (2007) 373-400.
6
[3] J.J. Chen, Y.C. Lin, P.L. Yao, A. Yuan, H.Y. Chen, C.T. Shun, M.F. Tsai, C.H. Chen,
7
P.C. Yang, Tumor-associated macrophages: the double-edged sword in cancer
8
progression, J. Clin. Oncol. 23(5) (2005) 953-64.
9
[4] D. Laoui, K. Movahedi, E. Van Overmeire, J. Van den Bossche, E. Schouppe, C.
SC
RI PT
1
Mommer, A. Nikolaou, Y. Morias, P. De Baetselier, J.A. Van Ginderachter, Tumor-
11
associated macrophages in breast cancer: distinct subsets, distinct functions, Int. J. Dev.
12
Biol. 55(7-9) (2011) 861-7.
13
[5] I.F. Lissbrant, P. Stattin, P. Wikstrom, J.E. Damber, L. Egevad, A. Bergh, Tumor
14
associated macrophages in human prostate cancer: relation to clinicopathological
15
variables and survival, Int. J. Oncol. 17(3) (2000) 445-51.
16
[6] G. Makin, C. Dive, Apoptosis and cancer chemotherapy, Trends Cell Biol. 11(11)
17
(2001) S22-6.
18
[7] S. Pervaiz, Anti-cancer drugs of today and tomorrow: are we close to making the turn
19
from treating to curing cancer?, Curr. Pharm. Des. 8(19) (2002) 1723-34.
20
[8] I. Herr, K.M. Debatin, Cellular stress response and apoptosis in cancer therapy,
21
Blood 98(9) (2001) 2603-14.
22
[9] R.E. Cocco, D.S. Ucker, Distinct modes of macrophage recognition for apoptotic and
23
necrotic cells are not specified exclusively by phosphatidylserine exposure, Mol. Biol.
24
Cell 12(4) (2001) 919-930.
25
[10] B. Fadeel, Programmed cell clearance, Cell. Mol. Life Sci. 60(12) (2003) 2575-85.
AC C
EP
TE
D
M AN U
10
22
3
ACCEPTED MANUSCRIPT
[11] T. Shree, O.C. Olson, B.T. Elie, J.C. Kester, A.L. Garfall, K. Simpson, K.M. Bell-
2
McGuinn, E.C. Zabor, E. Brogi, J.A. Joyce, Macrophages and cathepsin proteases blunt
3
chemotherapeutic response in breast cancer, Genes Dev. 25(23) (2011) 2465-79.
4
[12] E.M. Dijkgraaf, M. Heusinkveld, B. Tummers, L.T. Vogelpoel, R. Goedemans, V.
5
Jha, J.W. Nortier, M.J. Welters, J.R. Kroep, S.H. van der Burg, Chemotherapy alters
6
monocyte differentiation to favor generation of cancer-supporting M2 macrophages in
7
the tumor microenvironment, Cancer Res. 73(8) (2013) 2480-92.
8
[13] S.L. Shiao, L.M. Coussens, The tumor-immune microenvironment and response to
9
radiation therapy, J. Mammary Gland Biol. Neoplasia 15(4) (2010) 411-21.
SC
RI PT
1
[14] J.S. Russell, J.M. Brown, The irradiated tumor microenvironment: role of tumor-
11
associated macrophages in vascular recovery, Front. Physiol. 4 (2013) 157.
12
[15] H. Jackson, O. Muhammad, H. Daneshvar, J. Nelms, A. Popescu, M.A. Vogelbaum,
13
M. Bruchez, S.A. Toms, Quantum dots are phagocytized by macrophages and
14
colocalize with experimental gliomas, Neurosurgery 60(3) (2007) 524-9; discussion 529-
15
30.
16
[16] D.L. Thorek, D. Ulmert, N.F. Diop, M.E. Lupu, M.G. Doran, R. Huang, D.S. Abou,
17
S.M. Larson, J. Grimm, Non-invasive mapping of deep-tissue lymph nodes in live
18
animals using a multimodal PET/MRI nanoparticle, Nat Commun 5 (2014) 3097.
19
[17] M.P. Melancon, W. Lu, Q. Huang, P. Thapa, D. Zhou, C. Ng, C. Li, Targeted
20
imaging of tumor-associated M2 macrophages using a macromolecular contrast agent
21
PG-Gd-NIR813, Biomaterials 31(25) (2010) 6567-73.
22
[18] J. Gao, K. Chen, R. Luong, D.M. Bouley, H. Mao, T. Qiao, S.S. Gambhir, Z. Cheng,
23
A novel clinically translatable fluorescent nanoparticle for targeted molecular imaging of
24
tumors in living subjects, Nano Lett 12(1) (2012) 281-6.
AC C
EP
TE
D
M AN U
10
23
3
ACCEPTED MANUSCRIPT
[19] R. Landry, P.M. Jacobs, R. Davis, M. Shenouda, W.K. Bolton, Pharmacokinetic
2
study of ferumoxytol: a new iron replacement therapy in normal subjects and
3
hemodialysis patients, Am. J. Nephrol. 25(4) (2005) 400-10.
4
[20] M. Lu, M.H. Cohen, D. Rieves, R. Pazdur, FDA report: Ferumoxytol for intravenous
5
iron therapy in adult patients with chronic kidney disease, Am. J. Hematol. 85(5) (2010)
6
315-9.
7
[21] J.S. Weinstein, C.G. Varallyay, E. Dosa, S. Gahramanov, B. Hamilton, W.D. Rooney,
8
L.L. Muldoon, E.A. Neuwelt, Superparamagnetic iron oxide nanoparticles: diagnostic
9
magnetic resonance imaging and potential therapeutic applications in neurooncology
10
and central nervous system inflammatory pathologies, a review, J. Cereb. Blood Flow
11
Metab. 30(1) (2010) 15-35.
12
[22] J.P. Bullivant, S. Zhao, B.J. Willenberg, B. Kozissnik, C.D. Batich, J. Dobson,
13
Materials characterization of Feraheme/ferumoxytol and preliminary evaluation of its
14
potential for magnetic fluid hyperthermia, Int J Mol Sci 14(9) (2013) 17501-10.
15
[23] V.S. Balakrishnan, M. Rao, A.T. Kausz, L. Brenner, B.J. Pereira, T.B. Frigo, J.M.
16
Lewis, Physicochemical properties of ferumoxytol, a new intravenous iron preparation,
17
Eur. J. Clin. Invest. 39(6) (2009) 489-96.
18
[24] Y. Gossuin, P. Gillis, A. Hocq, Q.L. Vuong, A. Roch, Magnetic resonance relaxation
19
properties of superparamagnetic particles, Wiley Interdiscip Rev Nanomed
20
Nanobiotechnol 1(3) (2009) 299-310.
21
[25] H.E. Daldrup-Link, D. Golovko, B. Ruffell, D.G. Denardo, R. Castaneda, C. Ansari, J.
22
Rao, G.A. Tikhomirov, M.F. Wendland, C. Corot, L.M. Coussens, MRI of tumor-
23
associated macrophages with clinically applicable iron oxide nanoparticles, Clin. Cancer
24
Res. 17(17) (2011) 5695-704.
25
[26] W. Li, J. Salanitri, S. Tutton, E.E. Dunkle, J.R. Schneider, J.A. Caprini, L.N.
26
Pierchala, P.M. Jacobs, R.R. Edelman, Lower extremity deep venous thrombosis:
AC C
EP
TE
D
M AN U
SC
RI PT
1
24
3
ACCEPTED MANUSCRIPT
evaluation with ferumoxytol-enhanced MR imaging and dual-contrast mechanism--
2
preliminary experience, Radiology 242(3) (2007) 873-81.
3
[27] W. Li, S. Tutton, A.T. Vu, L. Pierchala, B.S. Li, J.M. Lewis, P.V. Prasad, R.R.
4
Edelman, First-pass contrast-enhanced magnetic resonance angiography in humans
5
using ferumoxytol, a novel ultrasmall superparamagnetic iron oxide (USPIO)-based
6
blood pool agent, J. Magn. Reson. Imaging 21(1) (2005) 46-52.
7
[28] E.A. Neuwelt, C.G. Varallyay, S. Manninger, D. Solymosi, M. Haluska, M.A. Hunt, G.
8
Nesbit, A. Stevens, M. Jerosch-Herold, P.M. Jacobs, J.M. Hoffman, The potential of
9
ferumoxytol nanoparticle magnetic resonance imaging, perfusion, and angiography in
10
central nervous system malignancy: a pilot study, Neurosurgery 60(4) (2007) 601-11;
11
discussion 611-2.
12
[29] M. Tian, X. Wen, E.F. Jackson, C. Ng, R. Uthamanthil, D. Liang, J.G. Gelovani, C. Li,
13
Pharmacokinetics and magnetic resonance imaging of biodegradable macromolecular
14
blood-pool contrast agent PG-Gd in non-human primates: a pilot study, Contrast Media
15
Mol Imaging 6(4) (2011) 289-97.
16
[30] E.F. Jackson, E. Esparza-Coss, X. Wen, C.S. Ng, S.L. Daniel, R.E. Price, B. Rivera,
17
C. Charnsangavej, J.G. Gelovani, C. Li, Magnetic resonance imaging of therapy-induced
18
necrosis using gadolinium-chelated polyglutamic acids, Int. J. Radiat. Oncol. Biol. Phys.
19
68(3) (2007) 830-8.
20
[31] A.M. Tang, J.S. Ananta, H. Zhao, B.T. Cisneros, E.Y. Lam, S.T. Wong, L.J. Wilson,
21
K.K. Wong, Cellular uptake and imaging studies of gadolinium-loaded single-walled
22
carbon nanotubes as MRI contrast agents, Contrast Media Mol Imaging 6(2) (2011) 93-9.
23
[32] L. Cassetta, R. Noy, A. Swierczak, G. Sugano, H. Smith, L. Wiechmann, J.W.
24
Pollard, Isolation of Mouse and Human Tumor-Associated Macrophages, Tumor
25
Microenvironment: Study Protocols 899 (2016) 211-229.
AC C
EP
TE
D
M AN U
SC
RI PT
1
25
3
ACCEPTED MANUSCRIPT
[33] E.A. Sykes, Q. Dai, K.M. Tsoi, D.M. Hwang, W.C.W. Chan, Nanoparticle exposure
2
in animals can be visualized in the skin and analysed via skin biopsy, Nature
3
Communications 5 (2014).
4
[34] S. Gordon, Alternative activation of macrophages, Nat. Rev. Immunol. 3(1) (2003)
5
23-35.
6
[35] S. Gordon, P.R. Taylor, Monocyte and macrophage heterogeneity, Nat. Rev.
7
Immunol. 5(12) (2005) 953-64.
8
[36] F.O. Martinez, L. Helming, S. Gordon, Alternative activation of macrophages: an
9
immunologic functional perspective, Annu. Rev. Immunol. 27 (2009) 451-83.
SC
RI PT
1
[37] A.J. Clear, A.M. Lee, M. Calaminici, A.G. Ramsay, K.J. Morris, S. Hallam, G. Kelly,
11
F. Macdougall, T.A. Lister, J.G. Gribben, Increased angiogenic sprouting in poor
12
prognosis FL is associated with elevated numbers of CD163+ macrophages within the
13
immediate sprouting microenvironment, Blood 115(24) (2010) 5053-6.
14
[38] G. Solinas, G. Germano, A. Mantovani, P. Allavena, Tumor-associated
15
macrophages (TAM) as major players of the cancer-related inflammation, J Leukocyte
16
Biol 86(5) (2009) 1065-1073.
17
[39] R.A. Mukhtar, O. Nseyo, M.J. Campbell, L.J. Esserman, Tumor-associated
18
macrophages in breast cancer as potential biomarkers for new treatments and
19
diagnostics, Expert Rev Mol Diagn 11(1) (2011) 91-100.
20
[40] J.L. Perry, K.G. Reuter, J.C. Luft, C.V. Pecot, W. Zamboni, J.M. DeSimone,
21
Mediating Passive Tumor Accumulation through Particle Size, Tumor Type, and
22
Location, Nano Letters 17(5) (2017) 2879-2886.
23
[41] K.C. Mei, J. Bai, S. Lorrio, J.T.W. Wang, K.T. Al-Jamal, Investigating the effect of
24
tumor vascularization on magnetic targeting in vivo using retrospective design of
25
experiment, Biomaterials 106 (2016) 276-285.
AC C
EP
TE
D
M AN U
10
26
3
ACCEPTED MANUSCRIPT
[42] Q. Cao, Z.B. Li, K. Chen, Z. Wu, L. He, N. Neamati, X. Chen, Evaluation of
2
biodistribution and anti-tumor effect of a dimeric RGD peptide-paclitaxel conjugate in
3
mice with breast cancer, Eur. J. Nucl. Med. Mol. Imaging 35(8) (2008) 1489-98.
4
[43] K.S. Klos, X. Zhou, S. Lee, L. Zhang, W. Yang, Y. Nagata, D. Yu, Combined
5
trastuzumab and paclitaxel treatment better inhibits ErbB-2-mediated angiogenesis in
6
breast carcinoma through a more effective inhibition of Akt than either treatment alone,
7
Cancer 98(7) (2003) 1377-85.
8
[44] R. Weissleder, M. Nahrendorf, M.J. Pittet, Imaging macrophages with nanoparticles,
9
Nat Mater 13(2) (2014) 125-38.
SC
RI PT
1
[45] Y. Higuchi, M. Oka, S. Kawakami, M. Hashida, Mannosylated semiconductor
11
quantum dots for the labeling of macrophages, J. Control. Release 125(2) (2008) 131-6.
12
[46] M. Verdoes, L.E. Edgington, F.A. Scheeren, M. Leyva, G. Blum, K. Weiskopf, M.H.
13
Bachmann, J.A. Ellman, M. Bogyo, A nonpeptidic cathepsin S activity-based probe for
14
noninvasive optical imaging of tumor-associated macrophages, Chem. Biol. 19(5) (2012)
15
619-28.
16
[47] M. Nahrendorf, E. Keliher, B. Marinelli, P. Waterman, P.F. Feruglio, L. Fexon, M.
17
Pivovarov, F.K. Swirski, M.J. Pittet, C. Vinegoni, R. Weissleder, Hybrid PET-optical
18
imaging using targeted probes, Proc. Natl. Acad. Sci. U. S. A. 107(17) (2010) 7910-5.
19
[48] S.S. Yu, C.M. Lau, S.N. Thomas, W.G. Jerome, D.J. Maron, J.H. Dickerson, J.A.
20
Hubbell, T.D. Giorgio, Size- and charge-dependent non-specific uptake of PEGylated
21
nanoparticles by macrophages, Int J Nanomedicine 7 (2012) 799-813.
22
[49] A. Moore, R. Weissleder, A. Bogdanov, Jr., Uptake of dextran-coated
23
monocrystalline iron oxides in tumor cells and macrophages, J. Magn. Reson. Imaging
24
7(6) (1997) 1140-5.
AC C
EP
TE
D
M AN U
10
27
3
ACCEPTED MANUSCRIPT
[50] C. Wilhelm, C. Billotey, J. Roger, J.N. Pons, J.C. Bacri, F. Gazeau, Intracellular
2
uptake of anionic superparamagnetic nanoparticles as a function of their surface coating,
3
Biomaterials 24(6) (2003) 1001-11.
4
[51] C. Li, A targeted approach to cancer imaging and therapy, Nat Mater 13(2) (2014)
5
110-115.
6
[52] K. Spaepen, S. Stroobants, P. Dupont, S. Van Steenweghen, J. Thomas, P.
7
Vandenberghe, L. Vanuytsel, G. Bormans, J. Balzarini, C. De Wolf-Peeters, L.
8
Mortelmans, G. Verhoef, Prognostic value of positron emission tomography (PET) with
9
fluorine-18 fluorodeoxyglucose ([18F]FDG) after first-line chemotherapy in non-
SC
RI PT
1
Hodgkin's lymphoma: is [18F]FDG-PET a valid alternative to conventional diagnostic
11
methods?, J. Clin. Oncol. 19(2) (2001) 414-9.
12
[53] M.J. Oborski, E. Demirci, C.M. Laymon, F.S. Lieberman, J.M. Mountz, Assessment
13
of early therapy response with 18F-FLT PET in glioblastoma multiforme, Clin. Nucl. Med.
14
39(10) (2014) e431-2.
15
[54] S.M. Eschmann, F. Paulsen, M. Reimold, H. Dittmann, S. Welz, G. Reischl, H.J.
16
Machulla, R. Bares, Prognostic impact of hypoxia imaging with F-18-misonidazole PET
17
in non-small cell lung cancer and head and neck cancer before radiotherapy, J. Nucl.
18
Med. 46(2) (2005) 253-260.
19
[55] K. Brindle, New approaches for imaging tumour responses to treatment, Nat. Rev.
20
Cancer 8(2) (2008) 94-107.
21
[56] T.L. Chenevert, P.E. McKeever, B.D. Ross, Monitoring early response of
22
experimental brain tumors to therapy using diffusion magnetic resonance imaging, Clin.
23
Cancer Res. 3(9) (1997) 1457-1466.
24
[57] D.C. Colvin, M.E. Loveless, M.D. Does, Z. Yue, T.E. Yankeelov, J.C. Gore, Earlier
25
detection of tumor treatment response using magnetic resonance diffusion imaging with
26
oscillating gradients, Magn. Reson. Imaging 29(3) (2011) 315-323.
AC C
EP
TE
D
M AN U
10
28
3
ACCEPTED MANUSCRIPT
[58] M. Lamuraglia, S.L. Bridal, M. Santin, G. Izzi, O. Rixe, A. Paradiso, O. Lucidarme,
2
Clinical relevance of contrast-enhanced ultrasound in monitoring anti-angiogenic therapy
3
of cancer: current status and perspectives, Crit. Rev. Oncol. Hematol. 73(3) (2010) 202-
4
12.
5
[59] M.C. Kolios, G.J. Czarnota, Potential use of ultrasound for the detection of cell
6
changes in cancer treatment, Future Oncology 5(10) (2009) 1527-1532.
7
[60] J. Weischenfeldt, B. Porse, Bone Marrow-Derived Macrophages (BMM): Isolation
8
and Applications, CSH Protoc 2008 (2008) pdb prot5080.
SC
RI PT
1
AC C
EP
TE
D
M AN U
9
29
3
ACCEPTED MANUSCRIPT
1
Legends
2 Figure 1. Structure and character of three nanoparticles: (A) QD710-Dendron, (B) PG-
4
Gd-NIR813, and (C) Ferumoxytol. (D) Characteristics of these three nanoparticles.
RI PT
3
5
Figure 2. Effect of Abraxane on mice bearing MDA-MB-435 breast tumors. (A) Growth
7
curves of MDA-MB-435 tumors treated with 5 daily doses of Abraxane or untreated
8
control. Day 0 indicates the day that the first of the 5 daily doses was administered.
9
(mean ± SE, n = 8/group). (B) Growth curves of MDA-MB-435 tumors treated with 1
10
dose of Abraxane or untreated control. Day 0 indicates the day that Abraxane was
11
administered. (mean ± SE, n = 5/group). (C) Staining for the apoptosis marker TUNEL
12
(green) and the activated macrophage marker CD169 (red) in untreated and Abraxane-
13
treated MDA-MB-435 tumors (DAPI nuclear stain, blue) (original magnification x100;
14
scale bar, 100 µm).
D
M AN U
SC
6
TE
15
Figure 3. Macrophages, but not tumor cells, internalized nanoparticles in vitro. (A)
17
QD710-D uptake after QD710-D incubation with RAW264.7 macrophages or MDA-MB-
18
435 tumor cells for 20 h (original magnification x600; scale bar, 20 µm). (B) Ferumoxytol
19
uptake was evaluated by Prussian blue staining after Ferumoxytol incubation with
20
RAW264.7 macrophages or MDA-MB-435 tumor cells for 1 h and 24 h (original
21
magnification x400; scale bar, 20 µm). (C) PG-Gd-NIR 813 uptake was assessed by T1-
22
weighted MRI after PG-Gd-NIR 813 incubation with RAW264.7 macrophages or MDA-
23
MB-435 tumor cells for 1 h and 24 h. (D) Quantitative analysis of T1-weighted MRI
24
signals intensity of PG-Gd-NIR 813 uptakes by RAW264.7 macrophages or MDA-MB-
25
435 tumor cells at 1 h and 24 h. (*** P < 0.001)
AC C
EP
16
26 30
3
ACCEPTED MANUSCRIPT
Figure 4. Administration of tumor-associated macrophages (TAMs) after Abraxane
2
treatment could be monitored by nanoparticle-based imaging. (A) Representative NIRF
3
images of Abraxane-treated and untreated MDA-MB-435 tumor–bearing mice 4 h after
4
intravenous injection of QD710-D. (B) Quantitative analysis of QD710-D signal
5
(photons/second) in untreated and Abraxane-treated tumors at 1, 2, 4, 18, and 24 h after
6
administration of QD710-D (**P < 0.01). (C) T2-weighted MR imaging with Ferumoxytol
7
for assessment of TAMs in MDA-MB-435 tumor after Abraxane treatment. T2-weighted
8
MR images of MDA-MB-435 tumor before and 1 and 24 h after injection of Ferumoxytol.
9
(D) Quantitative analysis of T2-weighted MRI signal intensity in tumors before and at 1
10
and 24 h after injection of Ferumoxytol. The signals were normalized to those of the
11
prescan images acquired from untreated control mice (** P < 0.01). Arrows: tumor.
12
(mean ± SD; n = 3/group).
M AN U
SC
RI PT
1
13
Figure 5. MR/NIRF optical imaging with PG-Gd-NIR813 for assessment of TAMs in
15
MDA-MB-435 tumors after Abraxane treatment. (A) NIRF optical imaging of untreated
16
and Abraxane-treated MDA-MB-435 tumors 48 h after injection of PG-Gd-NIR813.
17
Arrows: tumor. (B) Quantitative analysis of photon flux ratio between tumor and muscle
18
from NIR optical images acquired at 48 h after injection of PG-Gd-NIR813. (C) MR
19
images of MDA-MB-435 tumors before and 1, 24, and 48 h after injection of PG-Gd-
20
NIR813. (D) Quantitative analysis of T1-weighted MRI signals intensity in tumors before
21
and at 1, 24, and 48 h after injection of PG-Gd-NIR813. * P < 0.05; ** P < 0.01. All data
22
are expressed as mean ± SD (n = 3/group).
AC C
EP
TE
D
14
23 24
Figure 6. Tumor microenvironment cell population. (A) Tumor infiltrating leukocytes
25
detected by marker CD11b (green, original magnification x100; scale bar, 100 µm). (B)
26
FITC-CD11b staining showing the co-localization of QD710-D in leukocytes of MDA-MB31
3
ACCEPTED MANUSCRIPT
435 tumor tissue (original magnification x600; scale bar, 20 µm). (C) Flow cytometry of
2
dissected single cells from MDA-MB-435 tumor tissue showed significantly higher CD45+
3
myeloid cells; CD45+CD169+ macrophages infiltrated into tumor tissue of the Abraxane-
4
treated group compared with the untreated group. (D) Quantity analysis of infiltrating
5
CD45+ myeloid cells in tumor tissue single cells (*** P < 0.001). (E) CD45+CD169+
6
macrophages were the main part of these infiltrated myeloid cells and were significantly
7
higher in the Abraxane-treated group than in the untreated group (** P < 0.01). (F)
8
QD710-D nanoparticles had good co-localization with CD169-positive macrophages
9
(mean ± SD; n = 4/group).
SC
RI PT
1
M AN U
10
Figure 7. Flow cytometry analysis the tumor infiltrating immune cells on parent wild-type
12
MDA-MB-435 and resistant MDA-MB-435R tumors. (A) Untreated or Abraxane-treated
13
MDA-MB-435 wild-type tumor tissues were dissected into single-cell suspensions and
14
assessed by flow cytometry with fixable viability dye eFluor780, FITC-labeled CD45, PE-
15
labeled CD11b, and Percp.Cy5.5-labeled F4/80. (B) Untreated or Abraxane-treated
16
resistant MDA-MB-435R tumor tissues were dissected into single-cell suspensions and
17
assessed by flow cytometry with fixable viability dye eFluor780, FITC-labeled CD45, PE-
18
labeled CD11b, and Percp.Cy5.5-labeled F4/80. (C) Quantity data of negative cell
19
population with fixable viability dye eFluor780 channel showed that there was
20
significantly increased cell death of wild-type MDA-MB-435 tumors treated with
21
Abraxane compared with untreated tumors (* P < 0.05), but there were no differences in
22
the cell death ratio in resistant MDA-MB-435R tumors between the Abraxane-treated
23
and untreated groups. (D) Cell population quantity data of immunized cell infiltrated into
24
tumor tissue showed that there were significantly higher numbers of CD45+ myeloid cells,
25
CD11b+ leukocytes, and F4/80+ macrophages infiltrated into tumor tissue in the
26
Abraxane-treated group than in the untreated group for wild-type MDA-MB-435 tumors
AC C
EP
TE
D
11
32
3
ACCEPTED MANUSCRIPT (*** P < 0.001). However, there was a significantly lower populations of CD45+ myeloid
2
cells and CD11b+ leukocytes in the Abraxane-treated group than in the untreated group
3
for resistant MDA-MB-435R tumors (* P < 0.05), and there were no differences in F4/80+
4
macrophage of Abraxane-treated group compared with the untreated group for resistant
5
MDA-MB-435R tumors. Moreover, there were significantly lower populations of CD45+
6
myeloid cells, CD11b+ leukocytes, and F4/80+ macrophages in Abraxane-treated
7
resistant MDA-MB-435R tumors than in Abraxane-treated wild-type MDA-MB-435
8
tumors (### P < 0.001), (mean ± SD; n = 4/group).
SC
9
RI PT
1
Figure 8. Accumulation of QD710-D in parental MDA-MB-435 and Abraxane-resistant
11
MDA-MB-435R tumors with and without Abraxane treatment. (A) Representative optical
12
images at 4 h after QD710-D injection in mice with MDA-MB-435 and MDA-MB-435R
13
tumors untreated and treated with Abraxane. Yellow arrow, wild-type MDA-MB-435
14
tumor; red arrow, Abraxane-resistant MDA-MB-435R tumor. (B) Quantitative analysis of
15
tumor-to-muscle intensity ratio of optical images (** P < 0.01, * P < 0.05); Abraxane-
16
treated tumors compared with control tumors (### P < 0.001); Abraxane-treated
17
resistant MDA-MB-435R tumors compared with Abraxane-treated wild-type MDA-MB-
18
435 tumors (mean ± SD; n = 4/group).
19
MM435: MDA-MB-435; MM435R: MDA-MB-435R.
D
TE
EP
AC C
20
M AN U
10
33
3
ACCEPTED MANUSCRIPT
Figure 1.
2 3
AC C
EP
TE
D
M AN U
SC
RI PT
1
34
3
ACCEPTED MANUSCRIPT
Figure 2.
3
AC C
2
EP
TE
D
M AN U
SC
RI PT
1
35
3
ACCEPTED MANUSCRIPT
Figure 3.
2
AC C
EP
TE
D
M AN U
SC
RI PT
1
3
36
3
ACCEPTED MANUSCRIPT
Figure 4.
AC C
EP
TE
D
M AN U
SC
RI PT
1
2 3
37
3
ACCEPTED MANUSCRIPT
Figure 5.
AC C
EP
TE
D
M AN U
SC
RI PT
1
2
38
3
ACCEPTED MANUSCRIPT
Figure 6.
AC C
EP
TE
D
M AN U
SC
RI PT
1
2 3
39
3
ACCEPTED MANUSCRIPT
Figure 7.
AC C
EP
TE
D
M AN U
SC
RI PT
1
2 3
40
3
ACCEPTED MANUSCRIPT
Figure 8.
2 3
AC C
EP
TE
D
M AN U
SC
RI PT
1
41
3
ACCEPTED MANUSCRIPT
Supplementary Data
1 2
Macrophages as a Potential Tumor-Microenvironment Target for Noninvasive
4
Imaging of Early Response to Anticancer Therapy
RI PT
3
5 6
Qizhen Cao, Xinrui Yan, Kai Chen, Qian Huang, Marites P. Melancon, Gabriel Lopez,
7
Zhen Cheng, and Chun Li
SC
8
AC C
EP
TE
D
M AN U
9
42
3
ACCEPTED MANUSCRIPT
1
TUNEL staining Tissue slices (10 μm thick) were stained for TUNEL according to the
3
manufacturer-provided protocol. After staining, slides were mounted with DAPI-
4
containing medium, and fluorescent images were obtained with use of a fluorescence
5
microscope.
RI PT
2
6 7
Tumor model
MDA-MB-435 human breast cancer cells were harvested and washed with sterile
9
phosphate-buffered saline (PBS), suspended and adjusted the cell concentration of
10
5×107 cells/ml in PBS. Viable cells (5×106) in PBS (100 μl) were inoculated into the
11
mammary fat pad. Tumor growth was monitored by digital caliper with measuring
12
perpendicular diameters of the tumor. Tumor tissues were collected when tumors grew
13
around to 200 mm3.
M AN U
SC
8
Isolation of tumor-associated macrophages (TAMs)
TE
15
D
14
To prepare single-cell suspensions, harvested MDA-MB-435 tumor tissues were
17
cut into small fragments and digested with 0.25% collagenase type I (Life Technologies),
18
0.02% hyaluronidase (Sigma Roche), and 0.01% DNase I (Sigma Roche) in RPMI-1640
19
containing 10% FBS for 1 h at 37°C in water bath while shaking. Cell suspensions were
20
then passed through 100-micron cell strainers to remove aggregates. Single-cell
21
suspensions were counted, and viability was determined by trypan blue dye. For cell
22
staining, single-cell suspensions were incubated with eFluor450-labeled CD45, PE-
23
labeled CD11b, eFluor660-labeled F4/80, FITC-labeled Ly6G, PE-Cy7-labeled Ly6C,
24
and cell viability dye eFluor506 for 30 min on ice (all fluorescence probes were
25
purchased from eBioscience). Cells were washed three times with PBS. These cells
AC C
EP
16
43
3
ACCEPTED MANUSCRIPT
1
were sorted with FACSAria Fusion Cell Sorter (BD Biosciences), and TAMs were
2
isolated based on eFluor506-CD45+Ly6G-Ly6C-CD11b+F4/80+ cell gating [32].
3 Isolation of bone marrow-derived macrophages (BMDMs)
RI PT
4
To prepare L929-conditioned medium, L929 mouse fibroblast cells were grown in
6
flasks with RPMI-1640 medium containing 10% FBS in a humidified incubator with 5%
7
CO2 at 37°C for 7 days. Then, the supernatant of L929 cells were collected and filtered
8
through a 0.45-μm filter. These L929-conditioned medium were stored at −20°C.
SC
5
Bone marrow cells were obtained from the femur of female nude mice according
10
to reported procedures [60]. Briefly, cells from bone marrow were flushed, pipetted, and
11
suspended in RPMI-1640 medium with 10% FBS to give single-cell suspension. Cells
12
were then passed through a 100-μm cell strainer (Corning, New York, NY), counted, and
13
adjusted to a concentration of 1 ×106 cells/mL. Bone marrow cells were cultured in
14
BMDMs full culture medium (RPMI-1640 medium with 10% FBS plus 20% L929-
15
conditioned medium). Half of cell culture medium was changed with fresh BMDMs full
16
culture medium every other day. Under these culture conditions, the bone marrow
17
monocyte/macrophage progenitors proliferate and differentiate into a homogenous
18
population of mature BMDMs.
20 21
D
TE
EP
AC C
19
M AN U
9
Differentiation of M1- or M2 macrophage M1 macrophages were induced by addition of 20 ng/ml interferon-γ (IFN γ)
22
(BioLegend) and 10 ng/ml lipopolysaccharide (LPS) (List Biologics) to cultured TAMs or
23
BMDMs. M2 macrophages were induced by addition of 20 ng/ml interleukin-4 (IL-4)
24
(BioLegend) to cultured TAMs or BMDMs. Cells were stained with Alexa Fluor 488-
25
labelled CD86 and PE-labelled CD206 (BioLegend) as specific biomarkers for M1 and
26
M2 macrophages, respectively. 44
3
ACCEPTED MANUSCRIPT
1 2
Cellular uptake of Ferumoxytol nanoparticles in different TAM phenotypes TAMs, M1-polarized TAMs, M2-polarized TAMs, BMDMs, M1-polarized BMDMs,
4
and M2-polarized BMDMs were separately seeded in cell culture petri dishes.
5
Ferumoxytol nanoparticles were added to the cultured cells (final concentration, 200
6
µg/ml) and cells incubated at 37°C for 24 h. After washing steps, the cells were fixed
7
with a 1% paraformaldehyde and stained with Prussian blue (Ocean Nanotech, CA).
8
Images were acquired by a Zeiss microscope.
SC
9
RI PT
3
Ex vivo NIRF optical imaging with QD710-Dendron
11
Ex vivo NIRF optical imaging was performed after mice were euthanized 4 h after
12
QD710-Dendron injection. Heart, lung, liver, spleen, kidney, bone, skin, muscle, and
13
tumor tissues were removed and imaged with use of the IVIS-200 optical imaging
14
system (Caliper Life Sciences, Hopkinton, MA).
D
M AN U
10
TE
15
Ex vivo NIRF optical imaging with PG-Gd-NIR813
17
Ex vivo NIRF optical imaging was performed after mice were euthanized 48 h after PG-
18
Gd-NIR813 injection. Heart, lung, liver, spleen, kidney, muscle, and tumor tissues were
19
removed and imaged with use of the IVIS-200 optical imaging system (Caliper Life
20
Sciences).
AC C
21
EP
16
22
Cell proliferation assay
23
Tumor cell proliferation was analyzed by MTS assay. MDA-MB-435 or MDA-MB-435R
24
tumor cells were seeded in a 96-well plate (3×104 cells/ml, 100 μl per well) and
25
incubated for 24 h. Cells were then incubated in the presence of various concentrations
26
of paclitaxel at 37°C for 72 h or 96 h. MTS assay solution (20 μl) was added to each well, 45
3
ACCEPTED MANUSCRIPT
1
and cells were incubated for an additional 4 h. The optical density was measured at 490
2
nm by using a SpectraMax Plus plate reader (Molecular Devices, Sunnyvale, CA).
AC C
EP
TE
D
M AN U
SC
RI PT
3
46
3
ACCEPTED MANUSCRIPT
1
Figure Legends for Supplementary Data
2 Supplementary Figure S1. Apoptotic response in MDA-MB-435 tumor cells. Top, No
4
treatment control. Bottom, 5 days after a single dose of Abraxane at an equivalent
5
paclitaxel dose of 30 mg/kg. Blue, DAPI nuclear staining; green, apoptotic cells. (Original
6
magnification: x200. scale bar 50 µm).
RI PT
3
7
Supplemental Figure S2. Uptake of Ferumoxytol nanoparticles in TAMs isolated from
9
MDA-MB-435 tumors. (A) Representative flow cytometry gating of TAMs. TAMs are
SC
8
defined as CD45+Ly6G-Ly6C-CD11b+F4/80+ live cells. (B) Representative
11
microphotographs of TAMs, M1-polarized TAMs (stained with CD86, green), and M2-
12
polarized TAMs (stained with CD206, red) (original magnification x200, scale bar 50 µm).
13
(C) Ferumoxytol uptakes in TAMs, M1-polarized TAMs and M2-polarized TAMs after 24
14
h of incubation. Nanoparticles were stained with Prussian blue (original magnification
15
x200; scale bar, 50 µm).
D
TE
16
M AN U
10
Supplemental Figure S3. Uptake of Ferumoxytol nanoparticles in bone marrow derived
18
macrophages (BMDMs). (A) Flow cytometry characterization of M1-polarized BMDMs
19
and M2-polarized BMDMs. M1 BMDMs express high level of CD86 biomarker, M2
20
BMDMs express high level of CD206 biomarker. (B) ) Ferumoxytol uptakes in BMDMs,
21
M1 BMDMs, and M2 BMDMs after 24 h of incubation. Nanoparticles were stained with
22
Prussian blue (original magnification x200; scale bar, 50 µm).
AC C
EP
17
23 24
Supplementary Figure S4. (A) Ex vivo NIRF images of main organs removed from
25
mice 4 h after intravenous injection of QD710-D. (B) Quantitative analysis of QD710-D
26
signal (photons/second) in main organs removed from mice 4 h after QD710-D injection. 47
3
ACCEPTED MANUSCRIPT
1
**P < 0.01.
2 Supplementary Figure S5. (A) Ex vivo NIRF images of main organs removed from mice
4
48 h after intravenous injection of PG-Gd-NIR813. (B) Quantitative analysis of PG-Gd-
5
NIR813 (photons/second) in main organs removed from mice 48 h after PG-Gd-NIR813
6
injection. *P < 0.05.
RI PT
3
7
Supplementary Figure S6. Cell proliferation assay of wild-type MDA-MB-435 cells and
9
paclitaxel-resistant MDA-MB-435R cells. (A) Results of a cell proliferation assay 72 h
SC
8
after Abraxane treatment. ** P < 0.01. (B) Results of a cell proliferation assay 96 h after
11
Abraxane treatment. ** P < 0.01.
AC C
EP
TE
D
12
M AN U
10
48
3
ACCEPTED MANUSCRIPT
Supplementary Figure S1
3
AC C
2
EP
TE
D
M AN U
SC
RI PT
1
49
3
ACCEPTED MANUSCRIPT
Supplementary Figure S2
A
CD11b+F4/80+
CD45+
Ly6G-Ly6C-
B
M1 TAM
CD86
M AN U
CD206
C
M2 TAM
SC
TAM
RI PT
1
TAM
M1 TAM
Ferumoxytol
D
2
M2 TAM
AC C
EP
TE
3
50
3
ACCEPTED MANUSCRIPT
Supplementary Figure S3
RI PT
A
BMDM
M1 BMDM
M2 BMDM
M AN U
B
PE-CD206 BMDM M2 BMDM
SC
Alexa Fluor 488-CD86 BMDM M1 BMDM
EP
TE
D
Ferumoxytol
AC C
1
51
3
ACCEPTED MANUSCRIPT
1 2
AC C
EP
TE
D
M AN U
SC
RI PT
Supplementary Figure S4
52
3
ACCEPTED MANUSCRIPT
Supplementary Figure S5
2 3
AC C
EP
TE
D
M AN U
SC
RI PT
1
53
3
ACCEPTED MANUSCRIPT
Supplementary Figure S6
A
72 h **
** **
B
96 h **
D
**
M AN U
SC
**
RI PT
1
**
AC C
2
EP
TE
**
54
3