ACTIVATION OF C-TYPE VIRUS DURING CHEMICALLY-INDUCED LEUKEMOGENESIS IN MICE

  • 1 January 1978
    • journal article
    • research article
    • Vol. 38  (3) , 729-735
Abstract
Repeated percutaneous applications of 7,12-dimethylbenz(a)anthracene in weanling DBA/2 and ST/a mice induced 100% leukemias with short latency periods. Endogenous C-type viruses were activated during treatment as evidenced by increased expression of the murine leukemia virus major core protein, p30, in blood and spleens and increased frequency of detection of ecotropic virus by cocultivation of splenocytes with SC-1 embryo cells. The treatment did not affect p30 expression in several nonlymphoid organs, and detection of xenotropic viruses in the splenocytes was decreased. Virus expression did not correlate with progression of disease in that high p30 levels were found in mice with relatively low spleen weights and p30 levels had no obvious connection to survival of the individual. 7,12-Dimethylbenz(a)anthracene treatment had little influence on p30 expression in spleens and blood from C3H and BALB/c mice, which are less sensitive to 7,12-dimethylbenz(a)anthracene-induced leukemogenesis. The results indicate an association of C-type virus activation with chemical induction of leukemia but do not necessarily imply an etiological role of the virus in the disease.