A lymphoid cell surface glycoprotein involved in endothelial cell recognition and lymphocyte homing in man

We describe a 90-kDa lymphocyte surface glycoprotein, recognized by the monoclonal antibody Hermes-1, that is involved in endothelial cell recognition and lymphocyte trafficking in man. This molecule is selectively expressed on normal or transformed lymphoid cells that are able to recognize and bind to high endothelial venules (HEV, specialized vessels that mediate lymphocyte exit from the blood into lymphoid organs); appears to be linked to HEV recognition function since, in fluorescence-activated cell sorting of variants of a cloned cell line, HEV binding ability co-selects with the Hermes-1 antigen; bears the predominant cell surface epitopes recognized by heterologous anti-human lymphocyte antibodies able to interfere with lymphocyte binding to HEV; and is structurally similar to a previously described mouse lymphocyte surface receptor for HEV. These findings demonstrate that the molecule defined by Hermes-1 either functions as a specific lymphocyte surface receptor for HEV, or is both precisely coregulated and physically and/or functionally associated with such receptors. The expression of this putative receptor for HEV on normal human lymphocyte populations parallels, and thus presumably helps determine, their migratory status in vivo. Hermes-1 should be a powerful tool for analyzing the role of endothelial cell recognition in the traffic of normal and neoplastic human lymphocytes.