Regulation of T cell activation and tolerance by PDL2

Y Zhang, Y Chung, C Bishop… - Proceedings of the …, 2006 - National Acad Sciences
Y Zhang, Y Chung, C Bishop, B Daugherty, H Chute, P Holst, C Kurahara, F Lott, N Sun…
Proceedings of the National Academy of Sciences, 2006National Acad Sciences
T cell activation and tolerance are regulated by costimulatory molecules. Although PD-1
serves as a crucial negative regulator of T cells, the function of its ligands, PDL1 and PDL2,
is still controversial. In this study, we created a PDL2-deficient mouse to characterize its
function in T cell activation and tolerance. Antigen-presenting cells from PDL2−/− mice were
found to be more potent in activation of T cells in vitro over the wild-type controls, which
depended on PD-1. Upon immunization with chicken ovalbumin, PDL2−/− mice exhibited …
T cell activation and tolerance are regulated by costimulatory molecules. Although PD-1 serves as a crucial negative regulator of T cells, the function of its ligands, PDL1 and PDL2, is still controversial. In this study, we created a PDL2-deficient mouse to characterize its function in T cell activation and tolerance. Antigen-presenting cells from PDL2−/− mice were found to be more potent in activation of T cells in vitro over the wild-type controls, which depended on PD-1. Upon immunization with chicken ovalbumin, PDL2−/− mice exhibited increased activation of CD4+ and CD8+ T cells in vivo when compared with WT animals. In addition, T cell tolerance to an oral antigen was abrogated by the lack of PDL2. Our results thus demonstrate that PDL2 negatively regulates T cells in immune responses and plays an essential role in immune tolerance.
National Acad Sciences