Identification by Fluorescent Antibody of Developmental Forms of Psittacosis Virus in Tissue Culture.

Summary 1. Developmental forms of psittacosis virus have been studied in mouse embryo liver tissue cultures in vitro by the fluorescent-antibody technic. 2. Inoculation of a large dose of virus resulted in the intracellular appearance of antigen in most of the outgrowing cells within 16 hours. A moderate dose of virus resulted in the focal distribution of specific fluorescence. When a small dose of virus was inoculated, no specific fluorescence was detected. 3. The evidence indicates that virus antigen is present in the developmental forms within the cytoplasm of infected cells throughout the various stages that make up the growth cycle of psittacosis virus.