- Email: [email protected]
T-Cell Function Declines before CD4+ T-Cell Count Reaches Critical Level in Patients with Perinatal Acquired HIV
AB112 Abstracts
363
Characterization of Th2 Induced Bronchial Associated Lymphoid Tissue (BALT) in a Mouse Model of Asthma
David M. Kemeny, BSc, PhD, FRCPath1, Yen L. Chua, BSc, MSc1, Chiung-Hui Huang, PhD2, Ka Hang Liong3, Kenneth Wong1, Sophie Q. Zhou4, Yafang Tang4, Michelle C. P. Low5, Yongliang Zhang3, Fred W. S. Wong3; 1National University of Singapore, Singapore, 2Department of Paediatrics, National University of Singapore, Singapore, 3National University of Singapore, 4Duke-NUS, 5National university of Singapore. RATIONALE: Lymphoid tissues in the lung are poorly appreciated compared with their counterparts in other tissues such as gut and skin. Inducible Bronchial associated lymphoid tissue (iBALT) has been demonstrated in response to influenza infection and neonatal exposure to bacterial products. By transfer of Th2 polarized transgenic CD4 T cells we have produced a localized lung inflammatory response that is characterized by hyper-eosinophilia, smooth muscle and goblet cell hyperplasia and the formation of iBALT. In this study we sought to characterize Th2 cell associated iBALT. METHODS: Mice were transferred with Th2 polarized transgenic CD4 T cells and challenged intranasally with recombinant allergen three times weekly for 3 weeks. Lungs were removed and paraffin embedded sections cut and stained with Hematoxylin and Eosin, Periodic Acid Schiff’’s or Masson’s Trichrome. Frozen lung sections were stained with florescence tagged anti-CD3, anti B220 and anti-CD11c monoclonal antibodies. Mice were treated with anti-IL-4/IL-13 monoclonal antibodies weekly. RESULTS: Within 15 minutes of the fourth challenge mice exhibited breathing difficulties accompanied by a sharp fall in temperature (from 37C to 30C). iBALT was detected in all challenged mice and found to contain B cells, T cells and dendritic cells. Neutralizing anti-IL-4/IL-13 inhibited inflammation by over 80% and reduced the number and size of iBALT by over 50% CONCLUSIONS: Th2 cytokine dependent iBALT is present in the lungs of severely allergic mice that are similar to those described following influenza infection. Prevention of Th2 iBALT formation represents a promising new target for asthma therapy.
SUNDAY
364
Lymphocyte Activation and Bone Turnover in HIVInfected Young Adults; A Sub-Study of Adolescent Medicine Trials Network Protocol 061
Lorena R. Wilson, MD1, Ruth Gakpo1, Bernard Fischer, DVM, PhD1, Bret Rudy, MD2, Maureen Goodenow, PhD3, Grace Aldrovandi, MD4, John Sleasman, MD1; 1Duke University Medical Center, Durham, NC, 2 New York University Langone Medical Center, New York, NY, 3University of Florida College of Medicine, Gainesville, FL, 4Children’s Hospital of Los Angeles, Los Angeles, CA. RATIONALE: HIV infection is associated with chronic inflammation contributing to long-term skeletal complications and bone loss. Cause of bone turnover in HIV-infected patients is unknown. We hypothesized that biomarkers of lymphocyte activation are associated with biomarkers of bone turnover in HIV-infected youth. METHODS: Young adults were selected for exploratory evaluation (n516, median age 21 years, 88% male) from those who enrolled in a prospective study of antiretroviral therapy (ART) prior to CD4 T-cell attrition. Studies were performed using cryopreserved cells and sera obtained prior to and at 24 or 48 weeks post ART initiation. Biomarkers of bone turnover, lymphocyte and macrophage activation were assayed using 13 plex Luminex assay or multi-parameter flow cytometry. A Spearman’s rank correlation (rs) was used to assess associations between biomarkers. RESULTS: The only association between bone turnover and macrophage activation was a negative correlation of soluble CD163 with ACTH following ART initiation (rs5-0.62, p50.01). The largest correlations were seen in measures of lymphocyte activation measured by soluble CD27, which correlated with adiponectin levels prior to ART (rs50.54, p50.04), and expression of lymphocyte activation markers on CD8
J ALLERGY CLIN IMMUNOL FEBRUARY 2016
Central Memory T-cells. Increased levels of CD28 expression and declines in CD38 and HLA DR expression correlated with increased levels of C-terminal telopeptide (rs50.57, rs5-0.50, and rs5-0.61, respectively; p<0.05). Similar associations were seen with levels of receptor activator of NFkB ligand and osteopontin. CONCLUSIONS: Bone turnover was more often associated with lymphocyte rather than macrophage activation. ART targets activated lymphocytes and its introduction may be beneficial in preventing early bone turnover.
365
T-Cell Function Declines before CD4+ T-Cell Count Reaches Critical Level in Patients with Perinatal Acquired HIV
Naveen Nannapaneni, MD1, Pavadee Poowuttikul, MD2, Elizabeth A. Secord, MD, FAAAAI2; 1Children’s Hospital of Michigan Department of Allergy & Immunology, Detroit, MI, 2Children’s Hospital of Michigan Department of Allergy Immunology, Detroit, MI. RATIONALE: Our HIV patients are evaluated for lymphocyte function by mitogen phytohemmagluttinin (PHA) stimulation and those with poor responses are closely monitored. We present a case-series of perinatal acquired HIV patients whose T-cell function declined in the presence of adequate CD4+ T-cell counts. METHODS: Mitogen cultures of 23 patients aged 2-17years-old were reviewed in addition to average CD4+ T-cell counts and HIV viral loads(VL) for the one-year period around mitogen testing. Appropriate PHA response was defined as ten times the control. Appropriately responding patients were compared to insufficient responders to examine differences in age, average CD+ count, and average VL. Data excluding patients younger than six years-old was also compared, owing to different cutoffs for normal CD4+ values in this age group. RESULTS: 10 of 23 patients had insufficient mitogen responses. Patients with appropriate mitogen responses were younger (9.6 vs. 12.2years of age), had higher average CD4+ counts (1147 vs. 797cells/mm3) and had a lower average VL (1252 vs. 4114copies/mL) compared to patients with inappropriately low responses. When patients younger than six years-old were excluded, the appropriate mitogen responders were younger (11.1 vs. 13.33years-old), had higher average CD4+ T-cell counts (1026 vs. 736cells/mm3) and a lower VL (240 vs. 7969copies/mL) compared to insufficient responders. CONCLUSIONS: Perinatal acquired HIV patients with insufficient T-cell function measured by PHA mitogen culture were older, had lower CD4+ counts, and higher viral loads than patients with normal T-cell function. This indicates functional decline precedes decrease in absolute count, making mitogen stimulation a useful tool in assessing perinatal HIV patients.
363
Characterization of Th2 Induced Bronchial Associated Lymphoid Tissue (BALT) in a Mouse Model of Asthma
David M. Kemeny, BSc, PhD, FRCPath1, Yen L. Chua, BSc, MSc1, Chiung-Hui Huang, PhD2, Ka Hang Liong3, Kenneth Wong1, Sophie Q. Zhou4, Yafang Tang4, Michelle C. P. Low5, Yongliang Zhang3, Fred W. S. Wong3; 1National University of Singapore, Singapore, 2Department of Paediatrics, National University of Singapore, Singapore, 3National University of Singapore, 4Duke-NUS, 5National university of Singapore. RATIONALE: Lymphoid tissues in the lung are poorly appreciated compared with their counterparts in other tissues such as gut and skin. Inducible Bronchial associated lymphoid tissue (iBALT) has been demonstrated in response to influenza infection and neonatal exposure to bacterial products. By transfer of Th2 polarized transgenic CD4 T cells we have produced a localized lung inflammatory response that is characterized by hyper-eosinophilia, smooth muscle and goblet cell hyperplasia and the formation of iBALT. In this study we sought to characterize Th2 cell associated iBALT. METHODS: Mice were transferred with Th2 polarized transgenic CD4 T cells and challenged intranasally with recombinant allergen three times weekly for 3 weeks. Lungs were removed and paraffin embedded sections cut and stained with Hematoxylin and Eosin, Periodic Acid Schiff’’s or Masson’s Trichrome. Frozen lung sections were stained with florescence tagged anti-CD3, anti B220 and anti-CD11c monoclonal antibodies. Mice were treated with anti-IL-4/IL-13 monoclonal antibodies weekly. RESULTS: Within 15 minutes of the fourth challenge mice exhibited breathing difficulties accompanied by a sharp fall in temperature (from 37C to 30C). iBALT was detected in all challenged mice and found to contain B cells, T cells and dendritic cells. Neutralizing anti-IL-4/IL-13 inhibited inflammation by over 80% and reduced the number and size of iBALT by over 50% CONCLUSIONS: Th2 cytokine dependent iBALT is present in the lungs of severely allergic mice that are similar to those described following influenza infection. Prevention of Th2 iBALT formation represents a promising new target for asthma therapy.
SUNDAY
364
Lymphocyte Activation and Bone Turnover in HIVInfected Young Adults; A Sub-Study of Adolescent Medicine Trials Network Protocol 061
Lorena R. Wilson, MD1, Ruth Gakpo1, Bernard Fischer, DVM, PhD1, Bret Rudy, MD2, Maureen Goodenow, PhD3, Grace Aldrovandi, MD4, John Sleasman, MD1; 1Duke University Medical Center, Durham, NC, 2 New York University Langone Medical Center, New York, NY, 3University of Florida College of Medicine, Gainesville, FL, 4Children’s Hospital of Los Angeles, Los Angeles, CA. RATIONALE: HIV infection is associated with chronic inflammation contributing to long-term skeletal complications and bone loss. Cause of bone turnover in HIV-infected patients is unknown. We hypothesized that biomarkers of lymphocyte activation are associated with biomarkers of bone turnover in HIV-infected youth. METHODS: Young adults were selected for exploratory evaluation (n516, median age 21 years, 88% male) from those who enrolled in a prospective study of antiretroviral therapy (ART) prior to CD4 T-cell attrition. Studies were performed using cryopreserved cells and sera obtained prior to and at 24 or 48 weeks post ART initiation. Biomarkers of bone turnover, lymphocyte and macrophage activation were assayed using 13 plex Luminex assay or multi-parameter flow cytometry. A Spearman’s rank correlation (rs) was used to assess associations between biomarkers. RESULTS: The only association between bone turnover and macrophage activation was a negative correlation of soluble CD163 with ACTH following ART initiation (rs5-0.62, p50.01). The largest correlations were seen in measures of lymphocyte activation measured by soluble CD27, which correlated with adiponectin levels prior to ART (rs50.54, p50.04), and expression of lymphocyte activation markers on CD8
J ALLERGY CLIN IMMUNOL FEBRUARY 2016
Central Memory T-cells. Increased levels of CD28 expression and declines in CD38 and HLA DR expression correlated with increased levels of C-terminal telopeptide (rs50.57, rs5-0.50, and rs5-0.61, respectively; p<0.05). Similar associations were seen with levels of receptor activator of NFkB ligand and osteopontin. CONCLUSIONS: Bone turnover was more often associated with lymphocyte rather than macrophage activation. ART targets activated lymphocytes and its introduction may be beneficial in preventing early bone turnover.
365
T-Cell Function Declines before CD4+ T-Cell Count Reaches Critical Level in Patients with Perinatal Acquired HIV
Naveen Nannapaneni, MD1, Pavadee Poowuttikul, MD2, Elizabeth A. Secord, MD, FAAAAI2; 1Children’s Hospital of Michigan Department of Allergy & Immunology, Detroit, MI, 2Children’s Hospital of Michigan Department of Allergy Immunology, Detroit, MI. RATIONALE: Our HIV patients are evaluated for lymphocyte function by mitogen phytohemmagluttinin (PHA) stimulation and those with poor responses are closely monitored. We present a case-series of perinatal acquired HIV patients whose T-cell function declined in the presence of adequate CD4+ T-cell counts. METHODS: Mitogen cultures of 23 patients aged 2-17years-old were reviewed in addition to average CD4+ T-cell counts and HIV viral loads(VL) for the one-year period around mitogen testing. Appropriate PHA response was defined as ten times the control. Appropriately responding patients were compared to insufficient responders to examine differences in age, average CD+ count, and average VL. Data excluding patients younger than six years-old was also compared, owing to different cutoffs for normal CD4+ values in this age group. RESULTS: 10 of 23 patients had insufficient mitogen responses. Patients with appropriate mitogen responses were younger (9.6 vs. 12.2years of age), had higher average CD4+ counts (1147 vs. 797cells/mm3) and had a lower average VL (1252 vs. 4114copies/mL) compared to patients with inappropriately low responses. When patients younger than six years-old were excluded, the appropriate mitogen responders were younger (11.1 vs. 13.33years-old), had higher average CD4+ T-cell counts (1026 vs. 736cells/mm3) and a lower VL (240 vs. 7969copies/mL) compared to insufficient responders. CONCLUSIONS: Perinatal acquired HIV patients with insufficient T-cell function measured by PHA mitogen culture were older, had lower CD4+ counts, and higher viral loads than patients with normal T-cell function. This indicates functional decline precedes decrease in absolute count, making mitogen stimulation a useful tool in assessing perinatal HIV patients.