title: The critical time of avian leukosis virus subgroup J-mediated immunosuppression during early stage infection in specific pathogen-free chickens.
abstract: The critical time of avian leukosis virus subgroup J (ALV-J)-mediated immunosuppression was determined by body weight, relative immune organ weight, histopathology, and presence of group specific antigen and antibodies in specific pathogen-free (SPF) chickens. CD4(+) and CD8(+) cell activity in the spleen, total and differential leukocyte counts in blood, and viral RNA levels in spleen were measured. Significant growth suppression was observed in the two ALV-J-infected groups. A strong immune response by infected groups was present in spleen at 2-weeks-of-age, but after 4-weeks-of-age, the response decreased quickly. The thymus and bursa showed persistent immunosuppression until 4-weeks-of-age. Proliferation of fibroblasts and dendritic cells were observed in immune organs at 4- and 5-weeks-of-age. However, the granulocyte cell number was markedly lower in the infected groups than in the control group. In group 1 (day 1 infection) CD4(+) cells increased during the second week but significantly decreased during the fourth week, while group 2 (day 7 infection) showed the opposite effect. Viral RNA increased significantly by the fourth week. These data identify 3~4 weeks post-infection as the key time at which the ALV-J virus exerts its immunosuppressive effects on the host.
authors: College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
authors: Feng
authors: F
authors: Wang
authors: Xiaowei
authors: X
authors: Wang
authors: Hongbo
authors: H
authors: Chen
authors: Jianzhu
authors: J
authors: Liu
authors: Ziqiang
authors: Z
authors: Cheng
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001353:Avian Leukosis / Q000276:immunology* / Q000635:transmission / Q000821:virology; D001354:Avian Leukosis Virus / Q000145:classification / Q000276:immunology*; D001835:Body Weight; D015704:CD4 Antigens / Q000097:blood; D016827:CD8 Antigens / Q000097:blood; D002645:Chickens; D002681:China; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D007108:Immune Tolerance; D007958:Leukocyte Count / Q000662:veterinary; D011201:Poultry Diseases / Q000276:immunology* / Q000635:transmission / Q000821:virology; D012367:RNA, Viral / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D013047:Specific Pathogen-Free Organisms; D013154:Spleen / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D015704:CD4 Antigens; D016827:CD8 Antigens; D012367:RNA, Viral