IDENTIFICATION OF THE VIRUS OF COLORADO TICK FEVER IN MOUSE TISSUES BY MEANS OF FLUORESCENT ANTIBODIES

Abstract

The fluorescent antibody technique of Coons was successfully used for identification of 34 Colorado tick fever virus isolates in suckling mice infected with suspensions of Dermacentor andersoni or with blood samples of various rodents (Citellus lateralis tescorum, C. columbianus columbianus, Eutamias amoenus) collected in nature. Sections of quick-frozen brain and heart tissues from suckling mice, used for isolation of the virus, were stained directly with anti-Colorado tick fever virus rabbit globulin labeled with fluorescein isothiocyanate. Specific staining, suggesting a reaction between the virus and its antibody, was characterized by a stippled design occurring primarily in the cytoplasm of nerve or tissue cells. In the brain, intensive staining was regularly found throughout the cortical layers and medullary substance of the cerebellum; most intensive reactions were observed in the cytoplasm of Purkinje cells. In the ventricular walls of the heart, staining appeared as numerous small fluorescent specks in the fibers of the myocardium and in the cytoplasm of epicardial cells.