J Immunol. 2026 Oct 1;215(10):vkag276. doi: 10.1093/jimmun/vkag276. ABSTRACT CTLA-4 is an inhibitory receptor on T cells that limits immune activation by competing with the co-stimulatory receptor CD28 for binding to CD80 and CD86 on antigen-presenting cells. Regulatory T cells (Tregs) employ CTLA-4-mediated transendocytosis as a key suppressive mechanism. Several CTLA4…

