Dl. Yin et al., INTERFERON-GAMMA INDUCES A DECREASE IN THE SUSCEPTIBILITY OF HUMAN GLIOMA-CELLS TO LYSIS BY LYMPHOKINE-ACTIVATED KILLER-CELLS, Neurosurgery, 35(1), 1994, pp. 113-118
WE STUDIED THE effect that treating two types of glioblastoma cell lin
es, U-87 MG and U-251 MG, with interferon (IFN)-gamma had on their sus
ceptibility to lysis by lymphokine-activated killer (LAK) cells. We al
so examined the participation of cell-adhesion molecules and major his
tocompatibility complex (MHC) class I and II antigens present on the t
arget cells in lysis by LAK cells. Treatment with IFN-gamma (1000 U/ml
) for 48 hours resulted in the increased expression of both intercellu
lar-adhesion molecule 1 and MHC class I antigens on tumor cells. In ad
dition, untreated tumor cells expressed neural-cell-adhesion molecules
and MHC class II antigens highly, but their expression was not affect
ed by IFN-gamma treatment. These changes in expression were accompanie
d by a decreased susceptibility to lysis by LAK cells. Treatment with
antisense-intercellular-adhesion molecule-1 oligonucleotide further in
hibited LAK lysis of target cells, following treatment with IFN-gamma.
In contrast, acid treatment of tumor cells after treatment with IFN-g
amma increased their susceptibility to lysis by LAK cells. These findi
ngs suggest that treatment of glioblastoma cells with IFN-gamma decrea
sed their susceptibility to lysis by LAK cells, and that this decrease
in susceptibility is attributable principally to the increased expres
sion of MHC class I antigen on target cells.