ia Szymanska1 *, Malgorzata Sobieszczanska-Malek2 , Agnieszka WieckowskaKarkucinska1 and Wieslawa Grajkowska1
1Department of Pathology, The Children Memorial Health Institute, Warsaw, Poland 2Department of Heart Failure and Transplantation, The National Institute of Cardiology, Warsaw, PolandFulltext PDF
Background: Data suggest that PDL1 expression in donor tissue can down-regulate recipient alloreactive T cell responses by interaction with the PD-1 receptor expressed on alloreactive T cells, thus limiting the local inflammation leading to rejection and vasculopathy. The aim of the study was to assess the relation between PDL-1 expression in Endomyocardial Biopsies (EMBs) of adult patients after heart transplantation and allograft rejection. Patients and Methods: The study included 15 patients with diagnosed Antibody-Mediated Rejection (AMR), 12 patients with diagnosed grade 2 R Acute Cellular Rejection (ACR), and 16 patients with no AMR or ACR. PDL-1 and C4d immunohistochemical stainings were performed in all EMBs of transplanted hearts included in the study. Graft rejection was evaluated according to ISHLT criteria. Patients with diagnosed allograft rejection had also assessed subsequent control biopsies until the microscopic image normalized. The non-parametric Student's t test was used to compare the results. Results: Six patients were diagnosed with AMR 1 (I), 4 with AMR 1 (H) and 5 with AMR 2. Among all 15 patients with AMR, 5 presented additionally grade 1R ACR features. The difference in PDL1 expression within the groups was very different from the rest (patients with simultaneous AMR and ACR had a higher percentage of marker tissue expression), while the individual groups did not differ statistically from each other. In biopsies with higher PD L1 expression, lesions were already minimized at the next control biopsy. Conclusion: It seems that higher tissue expression of PDL-1 may be associated with a faster graft rejection resolution; however, it is not related to the type of rejection.
PDL-1; Heart transplantation; Allograft tolerance
Szymanska S, lgorzata Sobieszczanska-Malek M, WieckowskaKarkucinska A, Grajkowska W. Tissue Expression of Ligand to Programmed Death Receptor 1 (PD L1) in Endomyocardial Biopsies of Patients after Heart Transplantation - Association with Allograft Rejection, Pilot Study. World J Surg Surgical Res. 2021; 4: 1350..