The expression of bovine lymphocyte antigen and response of Hereford cattle to vaccination against Boophilus microplus.

The influence of the bovine lymphocyte antigen MB5 on the immune response of Hereford cattle to antigens of the tick (Boophilus microplus) was examined. Groups of cattle having or lacking the antigen MB5 (MB5+ and MB5-, respectively) were vaccinated with either soluble extracts of the gut membrane of adult ticks and adjuvant or injected with adjuvant alone. Cattle vaccinated with soluble gut membrane were significantly protected from two challenges with ticks. Protection against ticks was not significantly affected by the presence or absence of the lymphocyte antigen MB5. Similarly, no differences occurred in antibody levels (measured by enzyme-linked immunosorbent assay) and cellular responses (measured by lymphocyte blastogenesis assay) in MB5+ and MB5- groups to gut antigen.