The natural killer T (NKT) cell ligand alpha-galactosylceramide demonstrates its immunopotentiating effect by inducing interleukin (IL)-12 production by dendritic cells and IL-12 receptor expression on NKT cells.

Kitamura H, Iwakabe K, Yahata T, Nishimura S, Ohta A, Ohmi Y, Sato M, Takeda K, Okumura K, Van Kaer L, Kawano T, Taniguchi M, Nishimura T
J Exp Med. 1999 189 (7): 1121-8

PMID: 10190903 · PMCID: PMC2193012 · DOI:10.1084/jem.189.7.1121

The natural killer T (NKT) cell ligand alpha-galactosylceramide (alpha-GalCer) exhibits profound antitumor activities in vivo that resemble interleukin (IL)-12-mediated antitumor activities. Because of these similarities between the activities of alpha-GalCer and IL-12, we investigated the involvement of IL-12 in the activation of NKT cells by alpha-GalCer. We first established, using purified subsets of various lymphocyte populations, that alpha-GalCer selectively activates NKT cells for production of interferon (IFN)-gamma. Production of IFN-gamma by NKT cells in response to alpha-GalCer required IL-12 produced by dendritic cells (DCs) and direct contact between NKT cells and DCs through CD40/CD40 ligand interactions. Moreover, alpha-GalCer strongly induced the expression of IL-12 receptor on NKT cells from wild-type but not CD1(-/-) or Valpha14(-/-) mice. This effect of alpha-GalCer required the production of IFN-gamma by NKT cells and production of IL-12 by DCs. Finally, we showed that treatment of mice with suboptimal doses of alpha-GalCer together with suboptimal doses of IL-12 resulted in strongly enhanced natural killing activity and IFN-gamma production. Collectively, these findings indicate an important role for DC-produced IL-12 in the activation of NKT cells by alpha-GalCer and suggest that NKT cells may be able to condition DCs for subsequent immune responses. Our results also suggest a novel approach for immunotherapy of cancer.

MeSH Terms (20)

Adjuvants, Immunologic Animals Cytotoxicity, Immunologic Dendritic Cells Drug Synergism Galactosylceramides Gene Expression Regulation Immunity, Cellular Interferon-gamma Interleukin-12 Killer Cells, Natural Ligands Lymphocyte Activation Lymphocyte Subsets Mice Mice, Inbred C57BL Mice, Knockout Receptors, Interleukin Receptors, Interleukin-12 Up-Regulation

Connections (1)

This publication is referenced by other Labnodes entities: