iNKT cells control mouse spontaneous carcinoma independently of tumor-specific cytotoxic T cells.
BACKGROUND
CD1d-restricted invariant NKT (iNKT) cells are a subset of T lymphocytes endowed with innate effector functions that aid in the establishment of adaptive T and B cell immune responses. iNKT cells have been shown to play a spontaneous protective role against experimental tumors. Yet, the interplay between iNKT and tumor-specific T cells in cancer immune surveillance/editing has never been addressed. The transgenic adenocarcinoma of the mouse prostate (TRAMP) is a realistic model of spontaneous oncogenesis, in which the tumor-specific cytotoxic T cell (CTL) response undergoes full tolerance upon disease progression.


RESULTS
We report here that lack of iNKT cells in TRAMP mice resulted in the appearance of more precocious and aggressive tumors that significantly reduced animal survival. TRAMP mice bearing or lacking iNKT cells responded similarly to a tumor-specific vaccination and developed tolerance to a tumor-associated antigen at comparable rate.


CONCLUSIONS
Hence, our data argue for a critical role of iNKT cells in the immune surveillance of carcinoma that is independent of tumor-specific CTL.
Bellone
Matteo
M
Cellular Immunology Unit, Division of Immunology, Transplantation and Infectious Diseases, Istituto Scientifico San Raffaele, Milan, Italy.
Ceccon
Monica
M
Grioni
Matteo
M
Jachetti
Elena
E
Calcinotto
Arianna
A
Napolitano
Anna
A
Freschi
Massimo
M
Casorati
Giulia
G
Dellabona
Paolo
P
D000230:Adenocarcinoma / Q000276:immunology*; D000818:Animals; D055610:Antigens, CD1d / Q000276:immunology*; D018450:Disease Progression; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011471:Prostatic Neoplasms / Q000276:immunology*
D055610:Antigens, CD1d