The effect of leukocyte-reduced platelet-rich plasma on the proliferation of autologous adipose-tissue derived mesenchymal stem cells1

Clinical application of platelet-rich plasma (PRP) and stem cells has become more and more important in regenerative medicine during the last decade. However, differences in PRP preparations may contribute to variable PRP compositions with unpredictable effects on a cellular level. In the present study, we modified the centrifugation settings in order to provide a leukocyte-reduced PRP and evaluated the interactions between PRP and adipose-tissue derived mesenchymal stem cells (ASCs). PRP was obtained after modification of three different centrifugation settings and investigated by hemogram analysis, quantification of protein content and growth factor concentration. ASCs were cultured in serum-free alpha-MEM supplemented with autologous 10% or 20% leukocyte-reduced PRP. Cell cycle kinetics of ASCs were analyzed using flow cytometric analyses after 48 hours. Thrombocytes in PRP were concentrated, whereas erythrocytes, and white blood cells (WBC) were reduced, independent of centrifugation settings. Disabling the brake further reduced the number of WBCs. A higher percentage of cells in the S-phase in the presence of 20% PRP in comparison to 10% PRP and 20% fetal calf serum (FCS) advocates the proliferation stimulation of ASCs. These findings clearly demonstrate considerable differences between three PRP separation settings and assist in safeguarding the combination of leukocyte-reduced PRP and stem cells for regenerative therapies