title: [Effect of in vitro storage on the biological activity of human platelet-rich plasma].
abstract: OBJECTIVE
  This study aims at investigating the biological activity of human platelet-rich plasma (hPRP) stored at different conditions and exploring the method of standardized application of hPRP in vitro.
  
  
  METHODS
  hPRPs of healthy donors were prepared by Curasan PRP kits and the platelet counts were tested. Each hPRP was activated by thrombin activator and hPRP-released growth factors (GFs) were collected and the levels of TGF-beta1 and PDGF-AB were measured using ELISA assay. Each sample was divided into 3 groups and stored at 4 degrees C, -20 degrees C and -70 degrees C respectively. After 2, 4, 6, 8, 10 days, the levels of GFs in each sample were measured using ELISA assay. Moreover, hPRP samples stored at different temperatures were supplemented into culture media of human adipose tissue-derived stromal cells (hADSCs) and MTT assays were applied to examine their biological activities.
  
  
  RESULTS
  The level of hPRP-released TGF-beta1 and PDGF-AB descended rapidly when stored in vitro and lower temperature was preferable condition for their storage. When stored for 10 days, the levels of TGF-beta1 and PDGF-AB stored at & -20 degrees C and -70 degrees C were significantly higher than that stored at 4 degrees C. In MTT assay, the similar results were obtained.
  
  
  CONCLUSIONS
  The hPRP-released GFs should be stored at low temperature condition to preserve the biological activity. Quantitative analysis of GFs can be used as a credible standard to evaluate the biological activity of hPRP.
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Yun-Song
authors.initials: YS
authors.lastname: Liu
authors.forename: Yong-Sheng
authors.initials: YS
authors.lastname: Zhou
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Zhu
mesh_terms: D000328:Adult; D001793:Blood Preservation / Q000379:methods*; D015925:Cryopreservation; D005260:Female; D006801:Humans; D008297:Male; D010982:Platelet-Derived Growth Factor / Q000378:metabolism*; D053657:Platelet-Rich Plasma / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
chemical_list: D010982:Platelet-Derived Growth Factor; D053773:Transforming Growth Factor beta1; C095477:platelet-derived growth factor AB