Polymorphism of alpha -lactalbumin gene and changes of the profile of peripheral blood lymphocytes in cows naturally-infected with bovine leukaemia virus.

摘要

This study was conducted to determine the relationship between alpha -lactalbumin ( alpha -LA) gene polymorphism and the profile of peripheral blood lymphocytes in animals naturally infected with bovine leukaemia virus. 71 Black-and-White breed cows, 3-6 years old, from a leukosis prevalent herd were used in the study. The polymorphism of the alpha -LA gene in the -1689 position was assayed with the PCR-RFLP method using Sdu I enzyme. The profile of peripheral blood lymphocytes was determined using immunofluorescence technique with monoclonal antibodies. Results revealed that there was an associations between alpha -LA gene polymorphism and the profile of peripheral blood lymphocytes mainly the CD4+ and CD8+ T lymphocytes. Moreover, a significant effect of BLV infection on the number of CD 19+ B lymphocytes and the percentage of CD2+, CD4+ and CD8+ T lymphocytes were recorded. The effect of the alpha -LA gene polymorphism and BLV infection on the profile of the peripheral blood lymphocytes was modified by the interaction of these two factors. It was exhibited by a different profile of changes among the EBL+ and EBL- cows. Bovine leukaemia virus also modified the changes in the percentage of B lymphocytes during the first three months after calving. It is concluded that alpha -LA gene polymorphism has a correlation with peripheral blood lymphocyte profile mainly CD4+ and CD8+ lymphocytes..