Molecular cloning and characterization of a defective recombinant feline leukaemia virus associated with myeloid leukaemia

Tzavaras, T., Stewart, M., McDougall, A., Fulton, R., Testa, N., Onions, D. E. and Neil, J. C. (1990) Molecular cloning and characterization of a defective recombinant feline leukaemia virus associated with myeloid leukaemia. Journal of General Virology, 71(2), pp. 343-354. (doi: 10.1099/0022-1317-71-2-343)

Abstract

The GM1 strain of feline leukaemia virus (FeLV) was isolated from a naturally occurring case of myeloid leukaemia and induces severe haematopoietic abnormalities, including myeloblastic leukaemia, on inoculation into cats. Molecular clones of FeLV-GM1 proviruses were obtained and studied by restriction enzyme mapping, blot hybridization and partial DNA sequence analysis. Two types of clone were isolated; the first was a replication-competent FeLV of subgroup A, resembling other low or minimally pathogenic FeLV-A isolates; the second was replication-defective with extensive deletions and mutations in gag and pol, although it has an intact env gene of subgroup B phenotype. Large segments of the defective proviruses, from the 5′ leader sequence upstream of the gag gene to the 5′ half of the env gene, show structural hallmarks of endogenous FeLV-related proviruses. Infectious FeLV-GM1 viruses recovered after transfection were tested for their leukaemogenic potential in newborn cats. Early polyclonal myeloproliferative changes were observed in cats inoculated with FeLV-A/GM1 alone, although these were more pronounced in animals receiving the full FeLV-AB/GM1 complex reconstituted by cotransfection of the defective virus FeLV-B with its FeLV-A helper. Analysis of viruses in the bone marrow showed that replication of the subgroup B component is delayed and restricted to a proportion of cats. Most of the infected cats developed persistent abnormalities of haematopoiesis and one progressed to disseminated myeloid leukaemia. The defective recombinant FeLV-B/GM1 appears to play an indirect but important role in myeloid leukaemogenesis.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fulton, Dr Ruth and Neil, Professor James and Stewart, Dr Monica and Onions, Professor David
• Authors: Tzavaras, T., Stewart, M., McDougall, A., Fulton, R., Testa, N., Onions, D. E., and Neil, J. C.
• College/School: College of Medical Veterinary and Life Sciences > School of Life Sciences; College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Journal of General Virology
• Publisher: Society for General Microbiology
• ISSN: 0022-1317
• ISSN (Online): 1465-2099