title: Effects of Platelet-Rich Plasma & Platelet-Rich Fibrin with and without Stromal Cell-Derived Factor-1 on Repairing Full-Thickness Cartilage Defects in Knees of Rabbits.
abstract: BACKGROUND
  The purpose of this study was to create biomaterial scaffolds like platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) containing stromal cell-derived factor-1 (SDF1) as a chemokine to induce hyaline cartilage regeneration of rabbit knee in a full thickness defect.
  
  
  METHODS
  We created a full thickness defect in the trochlear groove of thirty-six bilateral knees of eighteen mature male rabbits. The knees were randomly divided into six groups (group I: untreated control, group II: PRP, group III: PRF, group IV: Gelatin+SDF1, group V: PRP+SDF1, and group VI: PRF+SDF1). After four weeks, the tissue specimens were evaluated by macroscopic examination and histological grading, immunofluorescent staining for collagen type II, and analyzed for cartilage marker genes by real-time PCR. The data were compared using statistical methods (SPSS 20, Kruskal-Wallis test, Bonferroni post hoc test and P<0.05).
  
  
  RESULTS
  Macroscopic evaluations revealed that international cartilage repair society (ICRS) scores of the PRF+SDF1group were higher than other groups. Microscopic analysis showed that the ICRS score of the PRP group was significantly lower than other groups. Immunofluorescent staining for collagen II demonstrated a remarkable distribution of type II collagen in the Gel+SDF1, PRP+SDF1and PRF+SDF1groups compared with other groups. Real-time PCR analysis revealed that mRNA expression of SOX9 and aggrecan were significantly greater in the PRF+SDF1, PRP+SDF1, Gel+SDF1and PRF groups than the control group (P<0.05).
  
  
  CONCLUSIONS
  Our results indicate that implantation of PRF scaffold containing SDF1 led to the greatest evaluation scores of full-thickness lesions in rabbits.
authors.affiliation: Laboratory for Stem Cell Research, Department of Anatomical Sciences, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Soghra
authors.initials: S
authors.lastname: Bahmanpour
authors.affiliation: PhD Student in Anatomical Sciences, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Ghasemi
authors.affiliation: Tehran University of Medical Science, Tehran, Iran.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Sadeghi-Naini
authors.affiliation: Department of Anatomical Sciences, School of Medicine, Tehran University of Medical sciences, Tehran, Iran.
authors.forename: Iraj Ragerdi
authors.initials: IR
authors.lastname: Kashani
keywords: Cartilage; Chemokine CXCL12; Knee; Platelet rich fibrin; Platelet-rich plasma