Spontaneous expression of interferon genes in murine peritoneal macrophages: modulation during the in vitro aging.

The expression of interferon (IFN)-beta gene and its modulation during in vitro "aging" was studied in unstimulated peritoneal macrophages (PM) explanted from lipopolysaccharide (LPS)-responsive (Lps(h)) and LPS-hyporesponsive (Lps(d)) mice. A strong direct correlation between the LPS response of PM and their capacity to express low levels of IFN-beta was found. Moreover, the decay of antiviral state during in vitro cultivation was correlated with the turnover of IFN-beta mRNA. In the light of the multiple biologic effect of IFN, the constitutive expression of IFN-beta gene in PM can play a crucial role not only in the restriction of viral replication, but also in the modulation of cell differentiation and immune response.