Changes in Cd4~+ and Cd8~+ T-Cell Subpopulations in Chickens Vaccinated with La Sota or V4 Strains of Ndv

摘要

The host cell-mediated-immune response in chickens following immunization with the La Sota or V4 strain of Newcastle disease virus ( NDV) was compared by measuring changes of the percentages of CD4~+ and CD8~+ T lymphocytes in PBLs and spleens by flow cytometric analysis. The results showed that in both La Sota and V4 vaccinated chickens the percentage of CD4~+ T lymphocytes in PBLs was increased significantly at 3 days post-inoculation ( PI) , while the percentage of CD8~+ T lymphocytes was decreased at 3 days PI. Relatively higher percentages of CD4~+ and CD8~+ T lymphocytes were observed in PBLs and spleens of chickens vaccinated with the V4 strain, as compared with the La Sota strain, which could be due to a more vigorous lymphocyte proliferation response following exposure to the V4 strain as compared to La Sota. Differences in CD4~+ and CD8~+ T lymphocyte percentage distributions between La Sota and V4 vaccinated chickens were also noted following virulent virus challenge. The percentage of CD4~+ T lymphocytes in PBLs of chickens vaccinated with La Sota strain following challenge was higher than those vaccinated with V4 strain, while the percentages of splenic CD8~+ T lymphocytes in chickens vaccinated with V4 were higher at 3 and 8 days post-challenge, but lower at 1 day post-challenge than La Sota vaccinated chickens.