title: Advantages of pure platelet-rich plasma compared with leukocyte- and platelet-rich plasma in promoting repair of bone defects.
abstract: BACKGROUND
  High levels of pro-inflammatory cytokines in leukocyte- and platelet-rich plasma (L-PRP) may activate the nuclear factor κB (NF-κB) pathway to counter the beneficial effect of the growth factors on bone regeneration. However, to date, no relevant studies have substantiated this.
  
  
  METHODS
  L-PRP and pure platelet-rich plasma (P-PRP) were isolated. The in vitro effects of L-PRP and P-PRP on the proliferation, viability and migration of human bone marrow-derived mesenchymal stem cells (HBMSCs) and EaHy926, tube formation of EaHy926, and osteogenic differentiation of HBMSCs were assessed by cell counting, flow cytometry, scratch assay, tube formation assay, and real-time quantitative polymerase chain reaction (RT-PCR), western blotting and Alizarin red staining, respectively. The in vitro effects of L-PRP and P-PRP on the nuclear translocation of NF-κB p65, mRNA expression of inducible nitric oxide synthase and cyclooxygenase-2, and production of prostaglandin E2 and nitric oxid were assessed by western blotting, RT-PCR, enzyme-linked immunosorbent assay and Griess reaction, respectively. The in vivo effects of L-PRP or P-PRP preprocessed β-tricalcium phosphate (β-TCP) on the calvarial defects in rats were assessed by histological and immunofluorescence examinations.
  
  
  RESULTS
  P-PRP, which had similar platelet and growth factors concentrations but significantly lower concentrations of leukocytes and pro-inflammatory cytokines compared with L-PRP, promoted the proliferation, viability and migration of HBMSCs and EaHy926, tube formation of EaHy926 and osteogenic differentiation of HBMSCs in vitro, compared with L-PRP. The implantation of P-PRP preprocessed β-TCP also yielded better histological results than the implantation of L-PRP preprocessed β-TCP in vivo. Moreover, L-PRP treatment resulted in the activation of the NF-κB pathway in HBMSCs and EaHy926 in vitro while the postoperative delivery of caffeic acid phenethyl ester, an inhibitor of NF-κB activation, enhanced the histological results of the implantation of L-PRP preprocessed β-TCP in vivo.
  
  
  CONCLUSIONS
  Leukocytes in L-PRP may activate the NF-κB pathway via the increased pro-inflammatory cytokines to induce the inferior effects on bone regeneration of L-PRP compared with P-PRP. Hence, P-PRP may be more suitable for bone regeneration compared with L-PRP, and the combined use of P-PRP and β-TCP represents a safe, simple, and effective alternative option for autogenous bone graft in the treatment of bone defects.
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Yin
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Qi
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Yuelei
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Jiagen
authors.initials: J
authors.lastname: Sheng
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Zhengliang
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Shicong
authors.initials: S
authors.lastname: Tao
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China. xuetaoxie@163.com.
authors.forename: Xuetao
authors.initials: X
authors.lastname: Xie
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China. lixiaolin@sjtu.edu.cn.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China. zhangcq@sjtu.edu.cn.
authors.forename: Changqing
authors.initials: C
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D002113:Calcification, Physiologic; D002454:Cell Differentiation; D002460:Cell Line; D002465:Cell Movement; D049109:Cell Proliferation; D002470:Cell Survival; D005260:Female; D006801:Humans; D053583:Interleukin-1beta / Q000378:metabolism; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology; D008875:Middle Aged; D016328:NF-kappa B / Q000378:metabolism; D018919:Neovascularization, Physiologic; D010012:Osteogenesis; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D053657:Platelet-Rich Plasma / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D012886:Skull / Q000000981:diagnostic imaging / Q000473:pathology*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D014945:Wound Healing; D055815:Young Adult
chemical_list: D053583:Interleukin-1beta; D016328:NF-kappa B; D010982:Platelet-Derived Growth Factor; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A
keywords: Animal model; Bone regeneration; Leukocyte- and platelet-rich plasma; Nuclear factor κB; Platelet-rich plasma; Pure platelet-rich plasma