The growth of reovirus 3 in cultured rat embryos and implications for human reproductive failure.

Ten-day rat embryos were exposed to different concentrations of reovirus 3, heat-inactivated virus or diluent and then cultured for 48 h. An effect on embryonic growth and development was observed that required live virus. Virus concentrations of 10(6.0) TCID50 were embryolethal while 10(5.0) TCID50 killed about 20% of embryos and caused varying degrees of growth retardation in the remainder. Growth of the agent in the visceral yolk sac and embryonic tissues was confirmed by virus titration and immunofluorescent studies. Infectious virus was detected in the medium after 6-8 h and increased exponentially throughout the 48 h culture period, except for a check around 18 h. The significance of the findings in relation to previous animal studies and the potential importance of reovirus as a cause of human reproductive failure are discussed.