Different preparation methods to obtain platelet components as a source ofgrowth factors for local application

BACKGROUND: Autologous platelet components were recently used as part of ti ssue-engineering strategies in oral and maxillofacial surgery. Various prep aration methods were investigated to define standardized blood bank compone nts and to collect data on the growth factor content of human platelets bef ore and after storage. STUDY DESIGN AND METHODS: Apheresis platelets (AP), buffy coat-derived plat elets (BCP), platelets prepared by tube method (TP), and highly concentrate d samples prepared from AP and from BCP were evaluated for standard quality criteria of platelet components and for their concentration of transformin g growth factor (TGF)beta1, platelet-derived growth factor (PDGF)-AB, and P DGF-BB. AP were stored for 5 days. On Days 3 and 5, these components and fr eshly prepared, highly concentrated samples were evaluated for the same mea sures. RESULTS: Platelet concentration in TP was lower than that in the other grou ps (p <0.05). However, the concentrations of PDGF-AB, PDGF-BB, and TGF-beta 1 were comparable in the three groups. TP showed higher spontaneous CD62 ex pression than did AP and BCP. The three preparation procedures resulted in significantly different WBC contamination, with the highest levels in TP Fo r the whole series of measurements, there was a strong correlation between growth factor levels and platelet concentration (p<0.05), which was due to the face that the growth factor content of concentrated platelet samples wa s tenfold that of AF, BCP, and TP In TP, the WBC concentration was correlat ed with PDGF levels (p<0.05). After 5-day storage, the mean levels of PDGF- AB, PDGF-BB, and TGF-beta1 were 57.1, 43.0, and 72.0 percent of the initial values in AP. Overall, multiple regression analysis revealed the following factors influencing the measured growth factor concentrations: platelet co ncentration, baseline CD62 expression, lactate production, and WBC contamin ation. CONCLUSION: Various methods enable the preparation of platelet components a nd of highly concentrated components for local use according to standard bl ood banking criteria. The obtained components differ, particularly in their WBC content and in vitro platelet activation. These findings are relevant for planning and evaluating further studies of locally usable autologous pl atelet components.