GITR Research in Tumor Immunotherapy
Aliyah Weinstein, Ph.D.
Article
Investigation into new potential targets for tumor immunotherapy has been ongoing now for over a decade. One protein that has long been studied in this framework is GITR (TNFRSF18), a member of the TNF superfamily of proteins that is expressed on T cells. Its ligand, GITRL, is expressed on antigen presenting cells such as dendritic cells. This pathway modulates the T cell immune response through a dual mechanism1 that primarily enhances the proliferation of regulatory T cells (Tregs)2 and also enhances the metabolism of effector T cells3. Because of these dual effects, understanding how best to target GITR in the setting of immunotherapy has remained challenging. Luckily, advances have recently been seen, and the stimulatory effect on regulatory T cells does not appear to be a factor in the cancer setting.