LTA recognition by bovine γδ T cells involves CD36

Abstract

CD36 has recently been shown to facilitate monocyte Toll-like receptor 2 (TLR2) recognition of lipoteichoic acid (LTA), much like CD14 in TLR4 recognition of lipopolysaccharide. We previously found that bovine γδ T cells express CD36 transcripts. Here, we tested whether bovine γδ T cells express CD36 protein and if so, whether it functions in a manner similar to the monocyte molecule. CD36 transcripts and internal and cell surface protein could be detected in resting, sorted γδ T cells. Phorbol 12-myristate 13-acetate (PMA)/ionomycin treatment increased CD36 transcript levels (detectable at 4 h) and protein expression (internal and cell surface). Increased surface antigen expression was detectable by 24 h and was maximal at 72 h following PMA/ionomycin stimulation. Anti-CD36 monoclonal antibody inhibited increased macrophage-inflammatory protein-1α gene expression in γδ T cells activated by LTA. In conclusion, γδ T cells express CD36, previously thought to be a myeloid and endothelial cell-restricted surface antigen, and it contributes to responses by these cells to microbial LTA.