AUTHOR=Rovira Jordi , Ramirez-Bajo Maria Jose , Bañón-Maneus Elisenda , Hierro-Garcia Natalia , Lazo-Rodriguez Marta , Piñeiro Gaston J. , Montagud-Marrahi Enrique , Cucchiari David , Revuelta Ignacio , Cuatrecasas Miriam , Campistol Josep M. , Ricart Maria Jose , Diekmann Fritz , Garcia-Criado Angeles , Ventura-Aguiar Pedro 

TITLE=Immune Profiling of Peripheral Blood Mononuclear Cells at Pancreas Acute Rejection Episodes in Kidney-Pancreas Transplant Recipients

JOURNAL=Transplant International

VOLUME=Volume 35 - 2022

YEAR=2022

URL=https://www.frontierspartnerships.org/journals/transplant-international/articles/10.3389/ti.2022.10639

DOI=10.3389/ti.2022.10639

ISSN=1432-2277

ABSTRACT=Profiling of circulating immune cells may provide valuable insight to the pathophysiology of acute rejection in solid organ transplantation. Herein we aimed at characterizing the peripheral blood mononuclear cells in simultaneous kidney-pancreas transplant recipients. 
We conducted a retrospective analysis of patients with biopsy proven acute rejection (BPAR) and compared to those with biopsy evidence of absence of rejection (No-AR). In a biopsy-matched analysis (n=67; 41% BPAR) we identified that CD3+ T cells, including both CD8+ and CD4+ T cell lineages, as well as higher percentage of CD19+ B cell population (p<.05) were increased in patients with BPAR. This difference was more pronounced in biopsies performed in the early post-transplant period (<3months), in which period immune subsets presented a good discriminative ability (CD4+ AUC 0.79; CD8+ AUC 0.80; B cells AUC 0.86; p<.05) and outperformed lipase for the diagnosis of acute rejection (AUC 0.62; p=.12). 
We further evaluated whether this could be related to the presence of differences in frequencies prior to transplantation, and identified that patients presenting with early post-transplant rejection (<3months) had a significant increase in T-cell frequencies at D0, both CD4+ T cells and CD8+ T cells (p<.01), and was associated with an significant inferior rejection-free graft survival.
T cell frequencies in peripheral blood at the day of pancreas transplantation correlated with the development of early acute rejection. Peripheral blood immune profiling may provide further information for the diagnosis of acute rejection in pancreas transplant recipients.