Role of adhesion molecules in recruitment of V delta 1 T cells from the peripheral blood to the tumor tissue of esophageal cancer patients

The mechanism responsible for tissue specific localization of gamma delta T cell subsets is not well understood. In order to explain the sequestration of specific gamma delta T cell subsets in the peripheral blood and tumor t issue of patients with esophageal cancer, we examined the function and expr ession of adhesion molecules on these cells. A hierarchy in the expression of adhesion molecules was observed. In vitro activated gamma delta T cells showed dominant expression of LFA-1 (CD11a), VLA-alpha4 (CD49d), intermedia te expression of VLA-alpha5 (CD49e) and L-selectin (CD62L), but low express ion of CD44v6 and alpha (E)beta (7) (CD103). It was observed that the gamma delta T cells use LFA-1, L-selectin and CD44v6 to bind to squamous cell ca rcinoma (SCC) cells, whereas they adhere to fibroblast cells using LFA-1, V LA-alpha4 and VLA-alpha5. V delta1 T cell subsets from the peripheral blood gamma delta T cells utilize a larger array of adhesion molecules, namely L FA-1, VLA-alpha4, VLA-alpha5, L-selectin and alpha (E)beta (7), to bind to SCC cells compared to the restricted usage of LFA-1, L-selectin and CD44v6 by the V delta2 T cells. Flow cytometric analysis of tumor infiltrating lym phocytes from the esophageal tumors confirmed the selective accumulation of V delta1(+) gamma delta T cells in the tumor compartment. It thus appears that adhesion molecules expressed on these lymphocytes play an important ro le in the recruitment and retention of V delta 1T cells in the tumor milieu .