Effect of γ-Interferon on the Expression of Major Histocompatibility Complex Class I and II Gene Products in Neural Cells Isolated from the Developing Human Fetal Peripheral Nervous System

The effect of gamma-interferon (gamma-IFN) on the expression of major histocompatibility complex (MHC) gene products was examined in the developing human fetal peripheral nervous system. RNA blot hybridization analysis of total RNA isolated from human fetal dorsal root ganglia (DRG) neural cell populations cultured in vitro for 5 days resulted in the detection of both MHC class I- and class II-specific RNAs. As determined by protein immunoblotting and fluorescence-activated flow cytometry, MHC class I and II proteins were also readily detectable in cultured human fetal DRG neural cell populations 5 days after isolation. In addition, treatment of 3-day human fetal DRG neural cells with gamma-IFN (100 U/ml; 48 h) resulted in a marked increase in the level of MHC class I- and class II-specific RNA and protein without inhibiting the proliferation of the neural cell population. These results suggest that changes in the levels of selected cytokines such as gamma-IFN may alter the ability of specific neural cell populations present in the developing human nervous system to participate in immune reactions by alteration of MHC class I and II antigen expression which may lead to perturbation in glial cell function and ultimately to nervous system dysfunction in general.