Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and PD-1/L1 checkpoint blockade. MHC, major histocompatibility complex; TCR, T cell receptor; PD-1, programmed cell death-1; PD-L1, programmed cell death ligand-1; +, B7 receptor expressed; −, B7 receptor not expressed.
