CD8+CD122+PD-1+ regulatory T cell (CD8+CD122+PD-1+ Treg)

CD8+CD122+PD-1+ regulatory T cells (Tregs) are a distinct subset of CD8+ T cells that function as potent immunosuppressors, distinguishing them from typical memory CD8+ T cells by their high expression of PD-1 [1, 3, 5]. Characterized by the expression of the IL-2/IL-15 receptor beta chain (CD122) and the co-inhibitory receptor PD-1, these cells maintain immune homeostasis and prevent autoimmune reactions primarily through the secretion of inhibitory cytokines such as IL-10 and TGF-beta [1, 2, 10]. Unlike the more common CD4+FoxP3+ Tregs, this CD8+ subset is generally FoxP3-negative and exhibits a central memory-like phenotype (CD44hiCD62Lhi) [1, 7, 12]. In clinical contexts, these cells are being explored as therapeutic targets: their expansion is desired to promote tolerance in organ transplantation and autoimmune diseases, while their activity is often inhibited by checkpoint inhibitors like anti-PD-1 antibodies to enhance anti-tumor immunity in cancer [2, 13, 14]. Their role as a "double-edged sword" makes them a critical focal point for precision immunotherapies [3, 13].

Other names

CD8+CD122+PD-1+ T cellCD8+CD122+ regulatory T cellMemory-like CD8+ regulatory T cellCD8+CD122+ suppressor T cellCD8+CD122+ subset

Drugs targeting this population work by either blocking PD-1 signaling to alleviate suppression in cancer [1, 9, 13] or utilizing IL-15 superagonists to expand the population and bolster immune regulation in autoimmune or transplant settings [1, 10, 11].