title: Growth Factor Release from Lyophilized Porcine Platelet-Rich Plasma: Quantitative Analysis and Implications for Clinical Applications.
abstract: BACKGROUND
  Freeze-dried platelet-rich plasma (FD PRP) is of potential value for clinical applications. However, growth factors released from FD PRP have not been well studied. Our study investigates growth factor release from FD PRP preparations, compared with other PRP samples, to further facilitate such clinical use.
  
  
  METHODS
  We used four experimental groups: (1) Fresh porcine PRP (PRP), (2) PRP activated by calcium chloride (CaCl2) (Ca PRP), (3) PRP activated by CaCl2, followed by freeze drying (Ca-FD PRP), and (4) PRP freeze-dried first, then activated by CaCl2 (FD-Ca PRP). All FD PRP samples were kept for up to 4 weeks at room temperature (22 °C) and reconstituted prior to analysis. Transforming growth factor-β1 (TGF-β1), platelet-derived growth factor AB (PDGF-AB), and vascular endothelial growth factor (VEGF) were quantitated by ELISA at 15 min and 1 h incubation times.
  
  
  RESULTS
  The concentrations of all growth factors in Ca PRP, measured at 1 h, were significantly higher than those in PRP (p < 0.05). PDGF-AB concentrations in FD-Ca PRP were not significantly different than in Ca PRP (p > 0.05). Levels of VEGF in Ca-FD PRP were not significantly different than in Ca PRP (p > 0.05). However, TGF-β1 concentrations in Ca-FD PRP, measured at 15 min, were higher than those in Ca PRP (p < 0.05).
  
  
  CONCLUSIONS
  PRP was activated efficiently by calcium chloride. Freeze-dried PRP remained rich in growth factors after storage for 4 weeks at room temperature, indicating its ease of use and wider possibilities for clinical applications.
  
  
  METHODS
  This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China.
authors.forename: Long
authors.initials: L
authors.lastname: Pan
authors.affiliation: Department of Plastic and Reconstructive Surgery, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Yong
authors.affiliation: Department of Plastic and Reconstructive Surgery, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China.
authors.forename: Kim Sun
authors.initials: KS
authors.lastname: Yuk
authors.affiliation: Department of Plastic and Reconstructive Surgery, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China.
authors.forename: Kim Young
authors.initials: KY
authors.lastname: Hoon
authors.affiliation: Department of Plastic and Reconstructive Surgery, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China.
authors.forename: Shi
authors.initials: S
authors.lastname: Yuedong
authors.affiliation: Department of Plastic and Reconstructive Surgery, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, China. xu.jianwei@zs-hospital.sh.cn.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Xu
mesh_terms: D000818:Animals; D005612:Freeze Drying; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis / Q000096:biosynthesis*; D053657:Platelet-Rich Plasma / Q000737:chemistry / Q000378:metabolism*; D013552:Swine
chemical_list: D036341:Intercellular Signaling Peptides and Proteins
keywords: Calcium chloride; Freeze drying; Platelet-derived growth factor; Platelet-rich plasma; Trehalose