title: Loss of antigenic epitopes as the result of env gene recombination in retrovirus-induced leukemia in immunocompetent mice.
abstract: The murine leukemia virus, E-55+ virus, induces a thymic lymphoma/leukemia in 100% of BALB.K mice infected as adults after a latent period of 4 months or more (Pozsgay et al., Virology 173, 330-334, 1989). Two molecular clones of virus designated E-55+ and E-55- based on their ability to encode the E-55 epitope detected by the monoclonal antibody 55 (mAb 55) were isolated from a leukemic BALB.K mouse inoculated with a biologically cloned E-55+ virus (Chesebro et al., Virology 112, 131-144, 1981). Env gene sequence analysis of E-55+ and E-55- clones showed that the E-55- virus was generated from the E-55+ virus as the result of a recombination between E-55+ virus and the endogenous ecotropic virus, emv-1, carried in the genome of the BALB.K mouse strain. The recombinant E-55- virus is replication competent. This recombination event and the consequential expression of E-55- virus consistently occur in immunocompetent BALB.K mice inoculated with the E-55+ virus and appear to play a role in the loss of epitopes recognized by virus neutralizing antibodies. The loss of these epitopes apparently allows the virus to evade the host immune response.
authors.affiliation: Department of Pathology, University of Pennsylvania, Philadelphia 19104-6142.
authors.forename: K M
authors.initials: KM
authors.lastname: Tumas
authors.forename: J M
authors.initials: JM
authors.lastname: Poszgay
authors.forename: N
authors.initials: N
authors.lastname: Avidan
authors.forename: S J
authors.initials: SJ
authors.lastname: Ksiazek
authors.forename: B
authors.initials: B
authors.lastname: Overmoyer
authors.forename: K J
authors.initials: KJ
authors.lastname: Blank
authors.forename: M B
authors.initials: MB
authors.lastname: Prystowsky
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000235:genetics* / Q000276:immunology*; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D015342:DNA Probes; D004279:DNA, Viral / Q000235:genetics / Q000302:isolation & purification; D000939:Epitopes / Q000235:genetics*; D015752:Genes, env; D015750:Genes, gag; D015751:Genes, pol; D016679:Genome, Viral; D009052:Leukemia Virus, Murine / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D007942:Leukemia, Experimental / Q000235:genetics* / Q000382:microbiology*; D008198:Lymph Nodes / Q000382:microbiology; D008223:Lymphoma / Q000235:genetics / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C / Q000382:microbiology; D008809:Mice, Inbred C3H; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D016133:Polymerase Chain Reaction / Q000379:methods; D011995:Recombination, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D013154:Spleen / Q000382:microbiology; D013950:Thymus Gland / Q000382:microbiology; D013953:Thymus Neoplasms / Q000235:genetics / Q000382:microbiology; D016662:Virus Integration
chemical_list: D000956:Antigens, Viral; D015342:DNA Probes; D004279:DNA, Viral; D000939:Epitopes; D009838:Oligodeoxyribonucleotides