The critical time of avian leukosis virus subgroup J-mediated immunosuppression during early stage infection in specific pathogen-free chickens.
10.4142/jvs.2011.12.3.235
- Author:
Feng WANG
1
;
Xiaowei WANG
;
Hongbo CHEN
;
Jianzhu LIU
;
Ziqiang CHENG
Author Information
1. College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China. czqsd@126.com
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
ALV-J;
avian;
immunosuppression;
leukosis;
leukosis virus subgroup J
- MeSH:
Animals;
Antibodies, Viral/blood;
Antigens, CD4/blood;
Antigens, CD8/blood;
Avian Leukosis/*immunology/transmission/virology;
Avian leukosis virus/classification/*immunology;
Body Weight;
*Chickens;
China;
Enzyme-Linked Immunosorbent Assay/veterinary;
Immune Tolerance;
Leukocyte Count/veterinary;
Poultry Diseases/*immunology/transmission/virology;
RNA, Viral/genetics;
Real-Time Polymerase Chain Reaction/veterinary;
Reverse Transcriptase Polymerase Chain Reaction/veterinary;
Specific Pathogen-Free Organisms;
Spleen/immunology
- From:Journal of Veterinary Science
2011;12(3):235-241
- CountryRepublic of Korea
- Language:English
-
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.
