Expression of class I MHC proteins on RIN-m5F cells is increased by interferon-γ and lymphokine-conditioned medium

Abstract

To examine whether products of the immune system interact with the pancreatic β-cell, rat insulinoma cells (RIN-m5F line) were cultured in the presence of conditioned medium from concanavalin A-activated mouse spleen cells (CAS medium). Indirect immunofluorescence and flow cytometry revealed that after culture in CAS medium, RN-m5F cells had an 8- to 10-fold increase in class II MHC proteins remained undetected, and the level of insulin and/or insulin-like growth factor 1 receptors was unchanged. The stimulation of class I MHC expression on RIN-m5F cells by CAS medium could be mimicked by recombinant interferon-γ. Analysis of 125I-surface-labeled cells by sodium dodecyl sulfate-polyacrylamid..