Influence of Enamel Matrix Derivative on Primary CD4+ T‐Helper Lymphocyte Migration, CD25 Activation, and Apoptosis

Abstract

Background: Enamel matrix derivative (EMD) has a low immunogenic potential. To the best of our knowledge, there are no studies on the influence of EMD on lymphocyte migration as a sensitive cellular reaction parameter. This study investigated the influence of EMD on primary T‐lymphocyte migration, CD25 activation, and activation‐induced cell death. Methods: After immunomagnetic‐positive CD4+ lymphocyte separation from peripheral blood taken from three healthy volunteers per trial, the influence of EMD on cell locomotion was assessed in a three‐dimensional collagen matrix migration model (CMMM). Direct CD4+ cell contact with EMD at concentrations of 25 and 100 μg/ml was mediated in a one‐phase CMMM. We investigated the indirect influence of EMD in a two‐phase CMMM: one collagen phase contained 25 and 100 μg EMD/ml, using the same concentrations, and a second adjacent phase contained T lymphocytes. After time‐lapse videomicroscopy, the mean locomoting percentage of 30 randomly selected cells was analyzed. Using flow cytometry, CD25 receptor activation was assessed, and annexin V was used for apoptosis detection in lymphocytes challenged with 0, 1, 25, 50, and 100 μg EMD/ml. Results: The one‐phase CMMM revealed a reduction and the two‐phase CMMM showed a dose‐dependent increase in the mean locomoting cell percentage ( P <0.001). Increasing EMD concentrations resulted in dose‐dependent enhanced T‐cell CD25 receptor expression and in increasing apoptosis ( P <0.001). Conclusions: Our study showed immediate effects of EMD on primary CD4+ lymphocyte migration, CD25 activation, and apoptosis. CD4+ lymphocyte apoptosis may be a further possible background for uneventful early wound healing as seen clinically as the result of EMD application.