Control of H-2 expression in transformed nonhaemopoietic cells by autocrine interferon.
The relationship between autocrine interferon (IFN) production and the expression of class I Major Histocompatibility Complex (MHC) membrane glycoproteins in vitro was investigated in a panel of murine transformed cells of nonhaemopoietic origin. The panel included 11 cell lines of H-2Kb haplotype derived from fibrosarcomas, carcinomas and melanoma, and from transformed fibroblasts. IFN activity was detected in the conditioned medium of nine cell lines; fibrosarcomas were among the high IFN producers, while the non-producers were a melanoma clone and a lung carcinoma cell line. A significant correlation was found between IFN production and the expression of H-2K/D glycoproteins, thus suggesting that long-term maintainment of MHC glycoprotein expression in vitro could be mediated by self produced IFN. Two IFN producer cell lines, MN/MCA1 and R80/17, were cultured in the presence of a blocking antiserum against IFN-alpha/beta: a significant decrease in H-2b expression was observed, thus indicating the existence of an autocrine IFN circuit. Taken together these findings suggest that release of IFN is a frequent event among transformed nonhaemopoietic cells, and that self-produced IFN contributes to the regulation of MHC antigen levels in solid tumours.
Nanni
P
P
Istituto di Cancerologia, Università di Bologna, Italy.
Landuzzi
L
L
Nicoletti
G
G
De Giovanni
C
C
Giovarelli
M
M
Lalli
E
E
Facchini
A
A
Lollini
P L
PL
D002277:Carcinoma / Q000378:metabolism; D002461:Cell Line, Transformed; D005347:Fibroblasts / Q000378:metabolism; D005354:Fibrosarcoma / Q000378:metabolism; D006183:H-2 Antigens / Q000096:biosynthesis*; D064532:Histocompatibility Antigen H-2D; D007372:Interferons / Q000096:biosynthesis*; D008175:Lung Neoplasms / Q000378:metabolism; D008285:Major Histocompatibility Complex; D008545:Melanoma / Q000378:metabolism; D009369:Neoplasms / Q000378:metabolism*
D006183:H-2 Antigens; C032876:H-2Kb protein, mouse; D064532:Histocompatibility Antigen H-2D; D007372:Interferons