H. Ishii et al., THE ENHANCEMENT OF CELL-SURFACE ICAM-1 AND HLA CLASS-I ANTIGENS IN HUMAN GASTRIC-CANCER CELL-LINES BY IFN-GAMMA, Acta medica Okayama, 48(2), 1994, pp. 73-79
Cytotoxic lymphocytes, including natural killer cells, lymphokine-acti
vated killer cells, and cytotoxic T lymphocytes, adhere to and lyse ca
ncer cells by recognizing cell surface antigens. Among the cell surfac
e antigens, intercellular adhesion molecule-1 (ICAM-1.) and HLA class
I antigen are important for the cytotoxic activity of lymphocytes. The
ICAM-1 and HLA class I antigen were examined in gastric cancer cell l
ines MKN-28 and MKN-45 by flow cytometry to determine whether their ex
pression on the cell surface is enhanced by interferon gamma (IFN-gamm
a). The cell expression rate [stained cells/10(4) cells x 100(%)] was
only 10% in ICAM-1 and about 20% in HLA class I antigen without lFN-ga
mma, but reached 70% in ICAM-1 and up to 60% in HLA class I antigen af
ter incubation with IFN-gamma for 24-96h. This enhanced expression of
cell surface ICAM-1 and HLA class I antigen by IFN-gamma might increas
e sensitivity for cytotoxic lymphocytes.