Autoantibodies after LVAD: Profiling with Antigen Microarrays

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The Journal of Heart and Lung Transplantation, Vol 32, No 4S, April 2013

Methods and Materials: 4EVERLUNG is a multi-center, randomized, controlled, open-label trial. Overall, 232 LTxR will be randomized to receive either Everolimus (C0-h 4⫾1ng/mL) þ reduced CNI (Tac C0h 3-5ng/mL or CsA C0h 50⫾25ng/mL) þ MPA þ steroids or standard CNI (Tac C0h 45ng/mL or CsA C0h 4100ng/mL) þ MPA þ steroids. Everolimus introduction and CNI reduction in the ‘‘quadruple low’’ arm should be achieved latest within two weeks post randomization. One primary objective is to demonstrate superior renal function after partial substitution of CNIs by Everolimus 12 months post randomization. Moreover, significant inhibition of the progression of bronchiolitis obliterans syndrom (BOS) could be an effect by using Everolimus. Key secondary objectives at the end of study include non-inferior efficacy (BPAR, graft loss, death), safety (infections, hypertension, hyperlipidemia) and evaluation of the patients quality of life (QoL, SF36). Results: Recruitment started in Feb 2012, whereas 21 patients at seven transplantation centers have been randomized in 4EVERLUNG until Nov 2012. Conclusions: Reducing CNI-dependent side effects such as chronic allograft nephropathy, which contribute to fatal long-term outcomes after Tx, represent one of the most pressing issues in transplantation. The results of 4EVERLUNG might therefore contribute to evaluate the benefit of an innovative ‘‘quadruple low’’ immunosuppressive regimen in LTxR by preserving renal function and/or limiting progression of BOS. 457 Survival Benefit of Lung Transplantation in Japan: Extreme Donor Shortage and the Potential Role of Living Transplantation M. Sato,1 K. Ohmori-Matsuda,2 T. Kondo,3 M. Chida,4 H. Date,1 M. Okumura,5 T. Oto,6 T. Shiraishi,7 T. Nagayasu.8 1Thoracic Surgery Kyoto University Hospital, Kyoto, Kyoto, Japan; 2Centre for Research on Inner City Health, St. Michael’s Hospital, Toronto, ON, Canada; 3 Institute of Development, Aging and Cancer, Division of Cancer Control, Thoracic Surgery, Tohoku University, Sendai, Miyagi, Japan; 4 Department of Thoracic and Cardiovascular Surgery, Dokkyo Medical University, Shimotsuga, Tochigi, Japan; 5Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan; 6Department of Thoracic Surgery, Okayama University Hospital, Okayama, Okayama, Japan; 7Department of Surgery, Division of Thoracic Surgery, Fukuoka University Hospital, Fukuoka, Fukuoka, Japan; 8Division of Surgical Oncology, Nagasaki Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan. Purpose: Cadaveric lung transplantation (LTx) in Japan has multiple limitations including 1) extreme donor shortage (only 44 cadaveric brain-death donors with 37 cadaveric LTx cases across Japan in 2011); 2) limited recipient age below 55 for bilateral and 60 for single LTx; 3) priority of LTx determined solely by waiting time on the list. Thus, living LTx could be the only life-saving option for those who cannot wait for cadaveric LTx. We examined the survival benefit of LTx (either cadaveric or living) among those who were listed for cadaveric LTx in Japan. Methods and Materials: The relative risks of death on the waiting list and death after LTx were evaluated using multivariate Cox models. Reception of LTx was treated as censored on the list. Since the initiation of the current Japanese listing system in 1998, patients who were listed by July 31, 2012 were included in the study. Results: 617 patients were listed and 174 received LTx (139 cadaveric, 35 living). Average waiting time for cadaveric LTx on the list was 966⫾676 (10-4507) days. In multivariate Cox regression models, idiopathic pulmonary fibrosis (IPF) showed the most significant risk of death on waiting list (n¼115; hazard ratio (HR), 3.53; confidence interval (CI), 2.34-5.31; reference, PAH), while the risk of death after LTx (n¼23, including cadaveric (n¼15) and living (n¼8)) was moderate (HR, 0.85; CI, 0.36-2.01; ref, PAH). Treating the conditions of being on cadacveric-LTx list and being post-LTx as time-dependent covariates, the estimated survival benefit of LTx was most significant in IPF (HR, 0.26; CI, 0.097-0.746). This trend persisted in subanalyses of living and cadaveric LTx. Conclusions: IPF showed the most significant survival benefit by LTx. This is explained by their poor prognosis without LTx and reasonable

outcome after LTx. Adult-to-adult living LTx, which appears suitable for relatively old IPF patients with small thorax, remains the only lifesaving option for many IPF patients who cannot wait for cadaveric LTx. 458 The Impact of Repeat HLA Mismatches on the Development of De Novo Donor Specific HLA Antbodies (DSA) in Lung ReTransplants M. Askar,1 P. Reville,1 J. Daghstani,1 L. Klingman,1 K. McCurry,2 M. Budev.3 1Allogen Laboratories Cleveland Clinic, Cleveland, OH; 2 Thoracic and Cardiovascular Surgery, Cleveland Clinic, Cleveland, OH; 3Pulmonary, Allergy and Critical Care Medicine, Cleveland Clinic, Cleveland, OH. Purpose: De Novo DSA is associated with increased risk of Bronchiolitis obliterans Syndrome (BOS) and allograft loss however the characteristics of De Novo DSA (DN DSA) that develops after repeat mismatched retransplant is unclear. We investigate the effect of repeat HLA mismatches on the development of DN DSA following lung retransplants. Methods and Materials: Our study included re-transplants at our institute (n¼15). We examined pre-Tx and DN DSA, as measured by single antigen Luminex beads specific to mismatched HLA antigens of the donor. Results: Distribution of positive T cell flow crossmatch to the 2nd donor by pre-Tx DSA, mean number of mismatches against the 1st, 2nd donors and repeat MM are shown in table 1. Characteristics of De novo DSA is shown in Table 2. Twelve recipients had repeat mismatches. Five developed DN DSA after 1st donor, 2 developed DN DSA after 2nd donor (one of them within the first month) and none developed DN DSA to a repeat mismatch (Table 2). Two individuals had a positive T cell crossmatch to the second donor. However, neither of these patients developed DSA after the second transplant. Table 1

T Cell XM Neg (n¼13) T cell XM Pos (n¼2)

Pre-Tx DSA

Mean # of 1st donor MM

Mean # of 2nd donor MM

Mean # of Rpt MM

12 (92%) 1 (50%)

7.2 (4-11) 9.5 (7-12)

7.9 (6-10) 6.5 (6-7)

1.8 (0-4) 2.1 (1-2)

Table 2 DSA to 1st DSA to 2nd DSA to Repeat Donor Donor MM (n¼0) (n¼5) (n¼2) Class I only

3 (60%)

2 (100%)

0

Class II Only Class I þ II DSA in the first month

2 (40%) 0 (0%) 0 (0%)

0 (0%) 0 (0%) 1 (50%)

0 0 0

DSA Specificity

A23, A31, A68, B7, B45, Cw7 DRw53, DQ2 NA A31

Conclusions: Based on a realtively limited number of repeat lung transplants, it appears that repeat HLA mismatches are not associated with increased risk of development of de novo DSA to these antigens. The impact of repeat HLA mismatches on long term transplant outcomes has not been assessed in this study. These results are clinically relevant to donor selection criteria for lung retransplants and warrant further investigation in a larger cohort. 459 Autoantibodies after LVAD: Profiling with Antigen Microarrays A. Chruscinski,1 J. Lioe,1 L. Grosman-Rimon,1 J. Hu,2 R. Pierson,2 V. Rao,1 H. Ross.1 1Multi-Organ Transplant Toronto General Hospital, Toronto, ON, Canada; 2Cardiac Surgery, University of Maryland Medical Center, Baltimore, MD.

Abstracts Purpose: Previous studies have documented B-cell activation and increases in anti-HLA antibodies after LVAD support. We sought to determine if autoantibodies (non-HLA) antibodies as measured by antigen microarrays also increase after LVAD support. Methods and Materials: We measured autoantibodies before and after LVAD support with antigen microarrays. Antigen microarrays were constructed by spotting 61 antigens onto nitrocellulose slides using a microarrayer. After blocking the slides, they were probed with diluted serum. They were then probed with fluorescently labeled secondary antibodies to differentially detect IgG and IgM reactivities. Fluorescent reactivities were detected with a scanner and significance analysis of microarrays (SAM) was used to detect significant changes in antigen reactivities. Total IgG levels were also measured by ELISA. Results: We measured autoantibodies before and after implantation of continuous flow LVADs in 22 patients. Mean duration of support was 102 days. SAM analysis revealed 14 autoantibodies that were increased after LVAD. Figure 1 shows a heatmap of pre and post reactivities. Thirteen of these reactivities were IgG and one was IgM. The antibodies that increased were against heart proteins such as myosin, troponin I, and tropomyosin as well as extracellular proteins such as collagen and laminin. Although not statistically significant, there was a trend for increases in autoantibodies to correlate with increases in PRA. Total IgG levels also increased after LVAD support from 15.9 to 17.8 mg/ml.

Conclusions: We identified 14 autoantibodies against heart and extracellular proteins that increased after LVAD support. Increases in these reactivities and total IgG may reflect immune activation F1 after LVAD. 460 The Clinical Impact of Ventricular Arrhythmias Following Continuous Flow Left Ventricular Assist Device Implantation A.R. Garan,1 K. Morrison,1 L. Letarte,1 J. Vazquez,1 D. Dano,1 P. Colombo,1 M. Yuzefpolskaya,1 R. Te-Frey,2 H. Takayama,2 Y. Naka,2 J. Morrow,1 H. Garan,1 U.P. Jorde,1 N. Uriel.1 1Cardiology. Columbia University Medical Center, New York, NY; 2Cardiothoracic Surgery, Columbia University Medical Center, New York, NY. Purpose: Ventricular arrhythmias (VA) are common in patients with a continuous flow left-ventricular assist device (CF-LVAD) but prospective data to support the routine ICD use in these patients are lacking. The aim of this study was to evaluate the prevalence and significance of Vas as well as the role of ICDs in this population. Methods and Materials: All patients with a long-term CF-LVAD receiving care at our institution were enrolled. ICDs were interrogated at baseline and throughout prospective follow-up. VA was defined as VT/VF lasting 4 30 seconds or effectively terminated by appropriate ICD therapy. The primary outcome was the occurrence of late Vas (more than 30 days after CF-LVAD implant); secondary outcomes were early Vas (within 30 days post-operatively) and all-cause mortality. Results: Ninety-four patients were enrolled; seventy-seven had an ICD and 17 did not. Five patients with an ICD had it de-activated or a depleted battery not replaced during the study. Patients without an ICD were more likely to be women (58.8% vs. 90.9%, p¼0.003), have shorter disease duration (35.3% vs. 97.4%, po0.001), and smaller left

S173 ventricular end-diastolic dimensions (5.8 þ 1.0cm vs. 7.0 þ 0.9cm, po0.001). Twenty-two patients (23.4%) had a late VA. Nineteen had an early VA; of these, 9 (47.4%) also had late Vas. Early Vas did not result in more hospital or ICU days during the index admission. Preoperative VA was the lone independent predictor of late VA; a lack of pre-operative VA conferred a low risk of late VA (4.0% vs. 45.5%; po 0.001). Six patients (6.4%) had a prolonged VA episode and all presented with right ventricular failure. There was no difference in survival between those with and without active ICD (90.5% vs. 85.6%; p¼0.55). Conclusions: CF-LVAD patients with pre-operative Vas are at risk of recurrent Vas. Active ICD may minimize the morbidities associated with sustained Vas. Patients without pre-operative Vas are at low risk of post-operative Vas and may not need ICD therapy. 461 Does Gender Influence Survival of Heart Transplant (HT) Recipients Bridged with LVAD Support? E.C. DePasquale, R.K. Cheng, A. Ardehali, A. Baas, M. Cadeiras, D. Cruz, T. Khuu, A. Nsair, M. Deng. Division of Cardiology David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA. Purpose: Gender differences in HT outcomes are well known. However, differences in those bridged with LVAD (BTT) have not been well studied. We sought to examine mortality differences in this population. Methods and Materials: 3020 HT pts BTT (exclusions:o18y, multiorgan, follow up loss) were identified from UNOS (2005-11) & stratified by sex. Survival was censored at 5y. Multivariate Cox proportional hazard regression was adjusted for age, DM, ischemic time, ethnicity, dialysis, life support, wait time & HLA mismatch. Results: Of 3020 pts, 18% were women. Ischemic (22 & 45%, men(M) & women(F) respectively) & dilated etiologies (69(M) & 49%(F)) were most prevalent. Women were younger & associated with lower BMI, less prior cardiac surgery & better renal function (Table). There was trend towards increased LVAD use in women (p¼0.054). Survival