Diabetes, Vol 34, Issue 11 1205-1209, Copyright © 1985 by American Diabetes Association
Interferon-gamma enhances the expression of the major histocompatibility class I antigens on mouse pancreatic beta cells
IL Campbell, GH Wong, JW Schrader and LC Harrison
Cell surface antigens of the major histocompatibility complex (MHC) play a
crucial role in the initiation of immune reactions. To investigate whether
the expression of MHC antigens on pancreatic islet cells could be altered,
we have cultured mouse islets in the presence of interferon-gamma
(IFN-gamma) and subsequently examined the levels of MHC antigen by indirect
immunofluorescence using monoclonal antibodies. IFN-gamma induced a 10-fold
increase in H-2K antigen expression on islet cells, the percentage of cells
with detectable H-2K expression increasing from 24% to 98%. The effects of
IFN-gamma on H-2D and la antigen expression were less marked, with only a
twofold increase in mean fluorescence levels, the percentage of cells with
detectable levels of expression increasing from 10% to 48% and 5% to 16%,
respectively. Using double-indirect immunofluorescence, it was demonstrated
that IFN-gamma enhanced expression of H-2K and H-2D antigens on beta-cells.
However la-positive beta-cells were undetectable in the presence or absence
of IFN-gamma. The ability of IFN-gamma to induce increased expression of
H-2 antigens on beta-cells may represent a mechanism for targeting immune
(cytotoxic) reactions to beta-cells, e.g., in autoimmune insulitis or
allograft rejection.