Discovery of non-HLA antibodies associated with cardiac allograft rejection and development and validation of a non-HLA antigen multiplex panel: From bench to bedside

Abstract

We analyzed humoral immune responses to nonhuman leukocyte antigen (HLA) after cardiac transplantation to identify antibodies associated with allograft rejection. Protein microarray identified 366 non-HLA antibodies (>1.5 fold, P < .5) from a discovery cohort of HLA antibody-negative, endothelial cell crossmatch-positive sera obtained from 12 cardiac allograft recipients at the time of biopsy-proven rejection. From these, 19 plasma membrane proteins and 10 autoantigens identified from gene ontology analysis were combined with 48 proteins identified through literature search to generate a multiplex bead array. Longitudinal sera from a multicenter cohort of adult cardiac allograft recipients (samples: n = 477 no rejection; n = 69 rejection) identified 18 non-HLA antibodies associated with rejection (P < .1) including 4 newly identified non-HLA antigenic targets (DEXI, EMCN, LPHN1, and SSB). CART analysis showed 5/18 non-HLA antibodies distinguished rejection vs nonrejection. Antibodies to 4/18 non-HLA antigens synergize with HLA donor-specific antibodies and significantly increase the odds of rejection (P < .1). The non-HLA panel was validated using an independent adult cardiac transplant cohort (n = 21 no rejection; n = 42 rejection, >1R) with an area under the curve of 0.87 (P < .05) with 92.86% sensitivity and 66.67% specificity. We conclude that multiplex bead array assessment of non-HLA antibodies identifies cardiac transplant recipients at risk of rejection. | 2769 BUTLER ET aL.

Non-HLA Antibodies and Epitope Mismatches in Kidney Transplant Recipients With Histological Antibody-Mediated Rejection

“…(39-41) which may be prevalent in KT recipients. Some of these autoantibodies and new ones recently validated (42) have not been evaluated in our cohort yet. They might explain some ABMR h DSA neg cases.…”

Autoantibodies to LG3 are associated with poor long‐term survival after liver retransplantation

“…Antibodies to non‐HLA antigens, such as autoantibodies or natural polyclonal antibodies, were also described in recipients of solid organs 12 and allogeneic hematopoietic stem cells 13 . Autoantibodies, which may be generated through the exposure of cryptic antigens, are detrimental for the survival of the kidney, 14‐16 lung, 17 heart, 18,19 liver, 20‐22 and intestinal 23 allografts. The prevalence of antibodies to HLA and autoantigens are often higher before retransplantation than before the first transplantation, especially in recipients of kidney grafts 24 .…”

Antibody Responses to Minor Histocompatibility Antigens After Solid Organ Transplantation

“…In kidney transplant recipients, serum immunoglobulin G (IgG) reactivity to autoantigens such as angiotensin II type 1 receptor, 3 endothelial cells, 4 or apoptotic cells 5 has been linked to reduced outcomes. In the heart, tubulin, 6 vimentin, myosin, 7 and other self-antigens 8,9 were associated with rejection processes and decreased overall graft survival following transplantation. Such autoreactivity may be the result of a dysregulated immune response, although the exact triggers are still unknown.…”