title: Quantification of platelets and platelet derived growth factors from platelet-rich-plasma (PRP) prepared at different centrifugal force (g) and time.
abstract: BACKGROUND
  Platelet derived biomaterials represent a key source of cytokines and growth factors extensively used for tissue regeneration; wound healing and tissue repair. Our study was to quantify platelets and growth factors released by PRP when prepared at different centrifugal force (g) and time.
  
  
  METHODS
  Our study was approved by the institutional ethical committee. One hundred millilitres of whole blood (WB) was collected in bag with CPDA as the anticoagulant(AC); (14 mL for 100 mL WB ratio). Nine aliquots of 10 mL each were made from the bag and set of three aliquots were made a group. PRP was prepared at varying centrifugal force (group A: -110 g, group B: -208 g & group C: -440 g) & time (1: -5 min, 2: -10 min & 3: -20 min). Contents of each PRP prepared were analysed. Commercial sandwich ELISA kits were used to quantify the concentrations of CD62P (Diaclone SAS; France), Platelet derived growth factors-AB (Qayee-Bio; China), transforming growth factor-β1 (DRG; Germany) and vascular endothelial growth factor (Boster Immuno Leader; USA) released in each PRP prepared.
  
  
  RESULTS
  Eight volunteers were enrolled in the study (24-30 years). The baseline blood counts of all the volunteers were comparable (p ≥ 0.05). Mean ± SD of platelet yield of all nine groups ranged from 17.2 ± 4.2% to 78.7 ± 5.7%. Each PRP was activated with calcified thromboplastin to quantify the growth factors released by them. Significantly higher (p < 0.05) transforming growth factor-β1 and vascular endothelial growth factor were released compared to the baseline.
  
  
  CONCLUSIONS
  Our study highlights the variation in both force (g) and time results in changes at cellular level and growth factor concentrations.
authors.affiliation: Department of Transfusion Medicine, Dr Ram Manohar Lohia Hospital, New Delhi, India. Electronic address: satyamarora83@gmail.com.
authors.forename: Satyam
authors.initials: S
authors.lastname: Arora
authors.affiliation: Department of Transfusion Medicine, Dr Ram Manohar Lohia Hospital, New Delhi, India.
authors.forename: Veena
authors.initials: V
authors.lastname: Doda
authors.affiliation: Department of Transfusion Medicine, Dr Ram Manohar Lohia Hospital, New Delhi, India.
authors.forename: Urvershi
authors.initials: U
authors.lastname: Kotwal
authors.affiliation: Department of Transfusion Medicine, Dr Ram Manohar Lohia Hospital, New Delhi, India.
authors.forename: Mitu
authors.initials: M
authors.lastname: Dogra
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000378:metabolism*; D002498:Centrifugation; D003710:Demography; D006801:Humans; D007962:Leukocytes / Q000378:metabolism; D019007:P-Selectin / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000378:metabolism*; D053657:Platelet-Rich Plasma / Q000378:metabolism*; D013997:Time Factors; D055815:Young Adult
chemical_list: D019007:P-Selectin; D010982:Platelet-Derived Growth Factor
keywords: Growth factors; Platelet biomaterials; Platelet rich plasma (PRP)