Mouse hepatitis virus type 4 (JHM strains). induced fatal central nervous system disease. I. genetic control and murine neuron as the susceptible site of disease

first, that the E + phenotype is controlled by a single gene; second, that this gene is dominant (for susceptibility) and is not linked to the major histocompatibility eomp|ex; and third, that susceptibility resides at the level of the neuronal cell Materials and Methods Virus. Wild-type MHV-4 initially provided by Dr. L. Weiner (Department of Neurology, University of Southern California) was plaque purified three times in NCTC-1469 cells, grown as a stock, and used in subsequent studies. The infectious titer, expressed as plaque-forming units per gram of tissue or per milliliter of cultured cells, was determined by plaque assay on either NCTC-1469 or L-24-1 cells. The handling of virus, culture, and plaque assay conditions have been reported elsewhere (11, 15) .