A virally inactivated functional growth factor preparation from human platelet concentrates


: Thierry Burnouf, Human Protein Process Sciences, Research Department, Lille, France. Tel.: + 33 32838 1930; fax: + 33 32042 1953
E-mail: tburnou@attglobal.net


Background  Human platelet growth factors (HPGF) are essential for tissue regeneration and may replace fetal bovine serum (FBS) in cell therapy. No method for the manufacture of standardized virally inactivated HPGF has been developed yet.

Study design and methods  Platelet concentrates (PC) were subjected to solvent/detergent (S/D) treatment (1% TnBP/1% Triton X-45), oil extraction, hydrophobic interaction chromatography and sterile filtration. Platelet-derived growth factor (PDGF)-AB, -BB and -AA, transforming growth factor-ß1 (TGF-ß1), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1) and vascular endothelium growth factor (VEGF) were measured by ELISA. Composition in proteins and lipids was determined, protein profiles were obtained by SDS-PAGE, and TnBP and Triton X-45 were assessed by gas chromatography and high-performance liquid chromatography, respectively. Cell growth promoting activity of HPGF was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay using human embryonic kidney (HEK293A) fibroblast and Statens Seruminstitute rabbit corneal (SIRC) epithelial cell lines.

Results  The GF preparation contained a mean of 16·66, 2·04, 1·53, 72·19, 0·33, 48·59 and 0·44 ng/ml of PDGF-AB, -BB, -AA, TGF-ß1, EGF, IGF-1 and VEGF, respectively. The protein profile was typical of platelet releasates and had less than 2 p.p.m. of residual S/D agents. MTS assay of HEK293A and SIRC cultures showed that the GF preparation at 10% and 0·1% (v/v), respectively, could successfully replace 10% FBS for cell proliferation. Cell-stimulating activity of HPGF on HEK293A was over twice that of PC releasates.

Conclusion  Standardized and functional virally inactivated HPGF can be prepared from human PC for possible applications in cell therapy and regenerative medicine.