Surface markers on human activated T lymphocytes. III. High-affinity E-rosette receptors

High-affinity E-rosette receptor (EhR) is suggested to be an activation marker of human T lymphocytes. The present study has been undertaken to estimate the dependence of EhR expression upon the T cell activation. To this aim the expression of EhR on T cells stimulated with PHA was examined. Nonsynchronized and arrested in G1 phase of cell cycle cultures of T lymphocytes were employed. The kinetics of expression of either de novo induced or reexpressed EhR was estimated by using two T cell subsets (originally EhR- and EhR+). In accordance with opinion of others, our results have shown that EhR is an activation marker of human T cells. Moreover, we have found that EhR is the marker of early and late activation stage because: its expression is induced in G1 phase of cell cycle, it continues to increase with the time of mitogen stimulation and the maximal level of EhR expression coincides with the time of the maximal RNA and DNA synthesis. Both induced de novo and reexpressed Eh receptors display the same expression kinetics.