Influence of platelet-derived growth factor-AB on tissue development in autologous platelet-rich plasma gels

Fibrin-based scaffolds are widely used in tissue engineering. We postulated that the use of platelet-rich plasma (PRP) in contrast to platelet-poor plasma and pure fibrinogen as the basic material leads to an increased release of autologous platelet-derived growth factor (PDGF)-AB, which may have a consequent positive effect on tissue development. Therefore, we evaluated the release of PDGF-AB during the production process and the course of PDGF release during cultivation of plasma gels with and w/o platelets. The influence of PDGF-AB on the proliferation rate of human umbilical cord artery smooth muscle cells (HUASMCs) was studied using XTT assay. The synthesis of extracellular matrix by HUASMCs in plasma- and fibrin gels was measured using hydroxyproline assay. The use of PRP led to an increase in autologous PDGF-AB release. Further, the platelet-containing plasma gels showed a prolonged release of growth factor during cultivation. Both PRP and platelet-poor plasma gels had a positive effect on the production of collagen. However, PDGF-AB as a supplement in medium and in pure fibrin gel had neither an effect on cell proliferation nor on the collagen synthesis rate. This observation may be due to an absence of PDGF receptors in HUASMCs as determined by flow cytometry. In conclusion, although the prolonged autologous production of PDGF-AB in PRP gels is possible, the enhanced tissue development by HUASMCs within such gels is not PDGF related.