Abstract
The programmed death (PD)-1-PD-1 ligand (PD-L) pathway, which is part of the B7-CD28 family, consists of the PD-1 receptor and its two ligands PD-L1 and PD-L2. Engagement of PD-1 by its ligands inhibits immune responses, and recent work has shown that PD-1 is highly expressed on exhausted T cells during chronic lymphocytic choriomeningitis virus (LCMV) infection in mice. Blockade of this pathway reinvigorates the exhausted T cells, allowing them to expand and produce effector cytokines, raising the issue of whether this pathway has been exploited by a variety of viruses during chronic infection. New studies now extend these observations to HIV infection and human disease.
Publication types
- Research Support, N.I.H., Extramural
- Research Support, Non-U.S. Gov't
- Review
MeSH terms
- Animals
- Arenaviridae Infections / immunology*
- B7-1 Antigen / immunology
- B7-1 Antigen / metabolism*
- B7-H1 Antigen
- Gene Expression Regulation / immunology*
- HIV Infections / immunology*
- Ligands
- Lymphocytic choriomeningitis virus*
- Membrane Glycoproteins / immunology
- Membrane Glycoproteins / metabolism*
- Mice
- Models, Immunological
- Peptides / immunology
- Peptides / metabolism*
- Signal Transduction / immunology*
- T-Lymphocytes / immunology*
- T-Lymphocytes / metabolism
- T-Lymphocytes / virology
Substances
- B7-1 Antigen
- B7-H1 Antigen
- Cd274 protein, mouse
- Ligands
- Membrane Glycoproteins
- Peptides