Resistance to PD1 blockade in the absence of metalloprotease-mediated LAG3 shedding.

ABSTRACT: Mechanisms of resistance to cancer immunotherapy remain poorly understood. Lymphocyte activation gene-3 (LAG3) signaling is regulated by a disintegrin and metalloprotease domain-containing protein-10 (ADAM10)- and ADAM17-mediated cell surface shedding. Here, we show that mice expressing a metalloprotease-resistant, noncleavable LAG3 mutant (LAG3^NC) are resistant to PD1 blockade and fail to mount an effective antitumor immune response. Expression of LAG3^NC intrinsically perturbs CD4⁺ T conventional cells (T_convs), limiting their capacity to provide CD8⁺ T cell help. Furthermore, the translational relevance for these observations is highlighted with an inverse correlation between high LAG3 and low ADAM10 expression on CD4⁺ T

SUBMITTER: Andrews LP 

PROVIDER: S-EPMC7901539 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature