Format

Send to

Choose Destination
Curr Mol Med. 2009 Aug;9(6):667-72.

The contrasting roles of NKT cells in tumor immunity.

Author information

1
Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1578, USA. berzofsk@helix.nih.gov

Abstract

NKT cells are true T cells that serve as a bridge between the innate and adaptive immune system, acting as first responders. They recognize lipid antigens rather than peptides, and respond to these when presented by a non-classical class I MHC molecule, CD1d. NKT cells can play a pathogenic role in asthma or a protective role against several autoimmune diseases, in part based on their cytokine profile. In cancer, they can play opposite roles, contributing to anti-tumor immunity or suppressing it. The protective NKT cells were found to be primarily type I NKT cells defined by use of a semi-invariant T cell receptor involving Valpha14Jalpha18 in mice and Valpha24Jalpha18 in humans and responding to alpha-galactosylceramide, and the most protective were among the minority that are CD4-. The suppressive NKT cells were found to be CD4+ and to be primarily type II NKT cells, that have diverse T-cell receptors and respond to other lipids. Further, the type I and type II NKT cells were found to counter-regulate each other, forming a new immunoregulatory axis. This axis may have broad implications beyond cancer, as NKT cells play a role in steering other adaptive immune responses. The balance along this axis could affect immunity to tumors and infectious diseases and responses to vaccines.

PMID:
19689293
PMCID:
PMC2729783
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Bentham Science Publishers Ltd. Icon for PubMed Central
Loading ...
Support Center