title: Nature of genetic resistance to Marek's disease in chickens.
abstract: Infection of line 6 resistant and line 7 susceptible chickens with Marek's disease virus (MDV) resulted in a depressed phytohemagglutinin (PHA) response and the presence of Marek's disease (MD) tumor-associated surface antigen (MATSA) in the spleens. At 6-10 weeks after infection, recovery in PHA response, diminution in the number of MATSA cells, and the presence of significant anti-MATSA immunity were observed in line 6 but not in line 7 chickens. Both lines had antibody-dependent cell-mediated antiviral immunity, but T-cell-mediated antiviral immunity was detected only in line 6 and the surviving line 7 chickens. Lymphoproliferative lesions were found only in line 7 chickens, an virus titers were significantly higher in line 7 than in line 6 chickens and embryos. Lymphoid organ weights and the number of lymphocytes of line 6 were significantly lower than those of line 7. These data suggests that resistance to MD in line 6 chickens was due to a) a deficiency in the aggregate number of target lymphocytes, b) a restriction in the ability to lymphocytes to nonproductively replicate MDV, and c) the involvement of cellular antiviral and antitumor immune responses.
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D002642:Chick Embryo; D002645:Chickens; D004198:Disease Susceptibility; D005260:Female; D008381:Herpesvirus 2, Gallid / Q000302:isolation & purification; D007111:Immunity, Cellular; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology; D008380:Marek Disease / Q000235:genetics / Q000276:immunology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D013154:Spleen / Q000276:immunology / Q000382:microbiology; D010948:Viral Plaque Assay
chemical_list: D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D010835:Phytohemagglutinins