Profiling posttransplant circulating antibodies in kidney transplantation using donor endothelial cells

E Canet, J Devalliere, N Gérard, G Karam, M Giral… - …, 2012 - journals.lww.com
E Canet, J Devalliere, N Gérard, G Karam, M Giral, B Charreau, S Coupel
Transplantation, 2012journals.lww.com
Background. Pathogenesis of antibody (Ab) responses to transplant are yet not well defined.
This study aimed to detect and to analyze posttransplant circulating allo-Abs reacting toward
graft endothelial cells (ECs) using primary EC cultures prospectively isolated from the
transplant donor at the time of transplantation. Methods. This study shows a retrospective
analysis performed using a dedicated EC crossmatch (ECXM) assay that we developed for
the experimental assessment of donor-specific EC-reactive Abs. Donor-specific ECXM was …
Abstract
Background.
Pathogenesis of antibody (Ab) responses to transplant are yet not well defined. This study aimed to detect and to analyze posttransplant circulating allo-Abs reacting toward graft endothelial cells (ECs) using primary EC cultures prospectively isolated from the transplant donor at the time of transplantation.
Methods.
This study shows a retrospective analysis performed using a dedicated EC crossmatch (ECXM) assay that we developed for the experimental assessment of donor-specific EC-reactive Abs. Donor-specific ECXM was performed by flow cytometry on posttransplant sera (n= 256) from an historical cohort of 22 kidney allograft recipients.
Results.
In this study, we show that 27.3%(6/22) of recipients have a positive ECXM that strictly correlates (100%, 6/6) with the presence of anti-human leukocyte antigen (HLA) Abs posttransplantation. ECXM identifies both donor-specific Abs (DSA; 50%) and non-DSA (50%) reactive to EC. DSA and non-DSA are mostly IgG1 and exhibit peak titers ranging from 1/8 to 1/1024. ECXM indicates that DSA correspond to anti-HLA class II Abs; this immunization is late (M3-M60) but persistent (still detected at M60). In contrast, non-DSA are non-HLA-type Abs reacting with third-party EC and reflecting an early but transient immunization (ended at M3-M12). Our findings demonstrate selective regulatory pathways initiated by anti-HLA class II and non-DSA in graft EC reflected by CCR4 and interleukin 1β up-regulation, respectively.
Conclusions.
We provide evidence that circulating Abs in HLA-sensitized transplant recipients include both DSA and non-HLA/non-DSA able to bind to graft EC and induce specific gene transcription.
Lippincott Williams & Wilkins