Specific adherence of thymocytes to a thymic medullary epithelial cell line.

TMF, a glycoprotein found preferentially at the contact points between thymocytes and thymic medullary epithelial cells, was investigated for its participation in adherence between these two cell types. It was found that thymocytes adhere specifically to a TMF+ cell line, that anti-TMF antibody can inhibit the adherence and that extraneous TMF can effectively compete with the adherence reaction. It is concluded that TMF is indeed involved in the temporary contact which occurs between thymocytes and medullary epithelial cells.