A novel virally inactivated human platelet lysate preparation rich in TGF-β, EGF and IGF, and depleted of PDGF and VEGF

There is emerging interest in the use of standardized virally inactivated human platelet lysate preparations rich in GFs (growth factors) for cell cultures, cell therapy and clinical applications. In the present paper, we report a simple process to prepare a virally inactivated platelet lysate preparation rich in TGF-beta 1 (transforming growth factor-beta 1), EGF (epidermal growth factor) and IGF (insulin-like growth factor) and depleted of PDGF (platelet-derived growth factor) and VEGF (vascular endothelial growth factor). Apheresis platelet concentrates were treated by the S/D (solvent/detergent) viral inactivation procedure, then subjected to an oil extraction followed by adsorption with activated charcoal and finally sterile-filtered. The resulting preparation contained a mean of 368.4, 2.4 and 54.7 ng/ml of TGF-beta 1, EGF and IGF respectively. PDGF-AB and VEGF were essentially completely removed by the charcoal treatment. The mean albumin, IgG, IgM and IgA and fibrinogen contents were approx. 40.0, 8.5, 0.87, 1.66 and 2.65 mg/ml respectively, cholesterol and triglycerides were at 15 and 20.7 mg/ml respectively and TnBP (tri-n-butyl phosphate) and Triton X-45 were at 8.7 and 8.8 p.p.m. respectively. Supplementing MEM (minimum essential medium) with 1-10% of this S/D-treated platelet lysate promoted the proliferation of MG63 and SIRC cell lines as well as, or better than, 10% (v/v) FBS (fetal bovine serum), as based on the MTS [3-(4, dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)2-(4-sulfophenyl)-2H-tetrazolium] assay. The process used to prepare such S/D-treated platelet lysates is easily scalable for industrial production. Our results open up the possibility to evaluate the potential of this new preparation for stem cell expansion and/or bone tissue engineering and regeneration.