A Circulating Bovine γδ T Cell Subset, Which Is Found in Large Numbers in the Spleen, Accumulates Inefficiently in an Artificial Site of Inflammation: Correlation with Lack of Expression of E-Selectin Ligands and L-Selectin

Tissue-specific localization of TCR-defined subsets of γδ T cells has been widely reported; however, the mechanisms responsible for this phenomenon are poorly understood. We describe a bovine γδ T cell TCR-associated subset that preferentially localizes in the spleen. This subset was characterized by coexpression of CD8, and was found to lack surface expression of E-selectin ligands, GR Ag ligands, as well as low expression of L-selectin. The CD8-positive γδ T cell subset did not accumulate at sites of inflammation as efficiently as CD8-negative γδ T cells that, in contrast, express E-selectin and GR ligands and high levels of L-selectin. This is the first demonstration of a γδ T cell subset, which exhibits a defined tissue tropism, having a unique adhesion molecule expression profile. These results demonstrate that in some cases tissue-specific accumulation of γδ T cell subsets can be predicted by expression, or lack of expression, of defined homing molecules.