title: Passive immunotherapy prevents expression of endogenous Moloney virus and amplification of proviral DNA in BALB/Mo mice.
abstract: BALB/Mo mice carrying the Moloney murine leukemia virus (M-MuLV) as an endogenous virus become viremic soon after birth and develop leukemia at a later age. M-MuLV-specific gene expression and an increase of virus-specific DNA copies in lymphatic target organs are characteristics of the preleukemic phase. Passive immunotherapy of new born BALB/Mo mice with anti-gp70 glycoprotein or anti-M-MuLV serum prevented viremia and delayed significantly the subsequent development of leukemia. Molecular hybridization experiments showed that both virus-specific genome transcription and virus-specific DNA amplification could be completely suppressed by antiserum treatment. Thus virus-specific RNA concentrations in target organs of immunized BALB/Mo mice of 6 months or older were as low as in normal BALB/c mice. This is an age at which untreated BALB/Mo mice have already developed malignant lymphoma. Our experiments demonstrate that treatment with antiserum interferes with the early events of virus expression and thus prevents the subsequent steps leading to leukemia.
mesh_terms: D000367:Age Factors; D000818:Animals; D005784:Gene Amplification; D005814:Genes, Viral; D007116:Immunization, Passive; D007140:Immunoglobulin Fab Fragments / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D009052:Leukemia Virus, Murine / Q000276:immunology; D007942:Leukemia, Experimental / Q000517:prevention & control; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology*; D008979:Moloney murine leukemia virus / Q000235:genetics*; D014766:Viremia / Q000517:prevention & control*
chemical_list: D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G