Identification of two distinct subsets of bovine γδ T cells with unique cell surface phenotype and tissue distribution


Dr N. D. MacHugh International Livestock Research Institute, P.O. Box 30 709, Nairobi, Kenya.


We describe the characterization of two subsets of bovine γδ T cells having distinct cell surface phenotype and tissue distribution. One population expresses the previously described 215 000 MW WC1 antigen and is negative for the cell-surface differentiation antigens CD2, CD4, and CD8. The second population expresses CD2 and CD8 but not WC1 and appears to have a T-cell receptor (TCR) rearrangement distinct from that of the WC1+ population. The WC1 population is found in large numbers in spleen and intestine. In addition, this subset is not recognized by a number of monoclonal antibodies (mAbs) specific for TCR families that are well represented in the WC1+ population. The results indicate that the γδ T-cell population in cattle is considerably larger than previously described and that this population can be subdivided into two distinct subsets based on cell-surface phenotype and tissue distribution.