Immune control of tumors by antigen presentation improvement.

REMEDI MM; DONADIO AC; BONACCI G; VIDES MA; DEPIANTE-DEPAOLI M

KARGER

Año: 2003 vol. 24 p. 228 - 228

p>Tumor cells cannot activate T lymphocytes, since they do not usually express major histocompatibility complex (MHC) class II molecules. Thus, tumor antigens can only be presented indirectly to T cells through professional antigen-presenting cells (APC). In our laboratory, we have treated a tumor cell line (Tu1-A) - derived from an induced rat mammary sarcoma - in order to increase the expression of MHC class I and class II molecules. In our tumor model, the transference of these induced cells into normal rats generated a tumor mass that exhibited a lower tumor growth rate and an earlier regression as compared to those observed in rats inoculated with wild-type Tu1-A cells. This earlier tumor regression was associated with the development of an antigen-specific immune response. 85-87% of the rats in both groups rejected the tumor and were alive at day 60 after tumor cell inoculation. However, in rats treated with wild-type cells the rejection was delayed and took place after tumor ul