Regulatory T Cells Inhibit T Cell Activity by Downregulating CD137 Ligand via CD137 Trogocytosis.

ABSTRACT: CD137 is a costimulatory molecule expressed on activated T cells. CD137 ligand (CD137L) is expressed by antigen presenting cells (APC), which use the CD137-CD137L system to enhance immune responses. It was, therefore, surprising to discover CD137 expression on regulatory T cells (Treg). The function of CD137 in Treg are controversial. While some studies report that CD137 signalling converts Treg to effector T cells (Teff), other studies find that CD137-expressing Treg display a stronger inhibitory activity than CD137- Treg. Here, we describe that CD137 on Treg binds to CD137L on APC, upon which one of the two molecules is transferred via trogocytosis to the other cell, where CD137-CD137L forms a complex that is internalized and deprives APC of the immune-stimulatory CD137L. Truncated forms

SUBMITTER: Luu K 

PROVIDER: S-EPMC7914903 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature