RELATIONSHIP BETWEEN FELINE LEUKEMIA-VIRUS ANTIGEN EXPRESSION AND VIRAL INFECTIVITY IN BLOOD, BONE-MARROW, AND SALIVA OF CATS

Abstract

Correlation was > 90% between feline leukemia virus (FeLV), group-specific antigen (GSA) in leukocytes, and viral infectivity (VI) in serum or plasma from 132 cats infected with the Rickard strain of FeLV, the Snyder-Theilen strain of feline sarcoma virus, or field strains of FeLV. Detection of GSA in blood cells was at least as sensitive as detection of VI in serum. In 45% of FeLV GSA-positive cats inoculated with FeLV-Rickard strain, VI was detected in saliva. No saliva samples from GSA- negative cats had VI. Sequential bone marrow biopsies from 34 cats inoculated with Snyder-Theilen feline sarcoma virus indicated that the correlation between FeLV GSA in bone marrow cells and blood cells was 100%. FeLV GSA appeared in bone marrow leukocyte precursors 1 wk before its appearance in peripheral blood leukocytes in 50% of the cats. The FeLV GSA positive state was transient (3-6 wk) in 34% of the Snyder-Theilen feline sarcoma virus inoculated cats.