A Soluble Antigen of Infectious Bronchitis Virus

Abstract

A soluble antigen of infectious bronchitis virus was detectable by immunodiffusion in chorioallantoic membranes of embryonating chicken eggs 12 hr after infection. The antigen was inactivated by heating at 60 C for 10 min, and by digestion with trypsin, and was not destroyed by DNase or RNase. The antigen was partially inactivated by treatment with acetone and chloroform but only a slight or no inactivation was observed by treatment with ether. The antigen was partially precipitated with ammonium sulfate. In sucrose gradient centrifugation the antigen sedimented slightly faster than chicken hemoglobin.