{Reference Type}: Journal Article
{Title}: Lymphocytes in Patients with Chronic Active Epstein-Barr Virus Disease Exhibited Elevated PD-1/PD-L1 Expression and a Prevailing Th2 Immune Response.
{Author}: Sun K;Wu C;Kong Q;Hu J;Shi L;Pi Y;Suolitiken D;Cui T;Chen L;He X;Song Z;Wu L;Wang J;Wang Z;
{Journal}: Mediterr J Hematol Infect Dis
{Volume}: 16
{Issue}: 1
{Year}: 2024
{Factor}: 3.122
{DOI}: 10.4084/MJHID.2024.037
{Abstract}: <B>UNASSIGNED: </B>Chronic active Epstein-Barr virus disease (CAEBV) is a proliferative disease of EBV+ T or natural killer (NK) cells with an unclear pathogenesis. This study aimed to examine the frequency and exhaustion levels of lymphocyte subsets in patients with CAEBV to further investigate the pathogenesis.<BR><B>UNASSIGNED: </B>Using flow cytometry, we detected the frequency, expression levels of programmed cell death 1 (PD-1) and programmed death ligand 1 (PD-L1), and EBV infection status of peripheral T subsets and NK cells in patients with CAEBV and healthy individuals.<BR><B>UNASSIGNED: </B>24 patients and 15 healthy individuals were enrolled in this study. Patients showed notably higher expression levels of PD-1 and PD-L1 in peripheral T subsets and NK cells compared to healthy individuals (P < 0.05). EBV+ lymphocytes exhibited significantly higher PD-L1 expression levels than EBV- lymphocytes. Additionally, the frequency of effector memory T (Tem) cells was significantly increased in patients, and the PD-L1 expression level was positively correlated with the EBV load. Besides, helper T cell 2 (Th2) immune bias, also favoring EBV amplification, was found in patients, including increased Th2 cell frequency, enhanced response capacity, and elevated serum levels of associated cytokines. The distribution and PD-1 expression levels of peripheral T subsets returned to normal in patients who responded to PD-1 blockade therapy.<BR><B>UNASSIGNED: </B>The up-regulation of the PD-1/PD-L1 pathway of peripheral T and NK cells and Th2 immune predominance jointly promoted EBV replication and the development of CAEBV. PD-1 blockade therapy reduced the PD-1 expression level of lymphocytes and helped normalize the distribution of the T subsets.