Platelet rich fibrin is not a barrier membrane!Or is it?

Platelet-rich fibrin(PRF)is widely used in dentistry and other fields of medicine,and its use has become popular in dental implantology.In several published studies,PRF has been used as a barrier membrane.A barrier membrane is a sheet of a certain material that acts as a biological and mechanical barrier against the invasion of cells that are not involved in bone formation,such as epithelial cells.Among the basic requirements of a'barrier membrane,occlusivity,stiffness,and space maintenance are the criteria that PRF primarily lacks;therefore,it does not fall under the category of barrier membranes.However,there is evidence that PRF membranes are useful in significantly improving wound healing.Does the PRF membrane act as a barrier?Should we think of adding or subtracting some points from the ideal requirements of a barrier membrane,or should we coin a new term or concept for PRF that will incorporate some features of a barrier membrane and be a combination of tissue engineering and biotechnology?This review is aimed at answering the basic question of whether the PRF membrane should be considered a barrier membrane or whether it is something more beyond the boundaries of a barrier membrane.

Intraarticular injections(corticosteroid, hyaluronic acid, platelet rich plasma) for the knee osteoarthritis

Osteoarthritis(OA)is a complex"whole joint"disease pursued by inflammatory mediators,rather than purely a process of"wear and tear".Besides cartilage degradation,synovitis,subchondral bone remodeling,degeneration of ligaments and menisci,and hypertrophy of the joint capsule take parts in the pathogenesis.Pain is the hallmark symptom of OA,but the extent to which structural pathology in OA contributes to the pain experience is still not well known.For the knee OA,intraarticular(IA)injection(corticosteroids,viscosupplements,blood-derived products)is preferred as the last nonoperative modality,if the other conservative treatment modalities are ineffective.IA corticosteroid injections provide short term reduction in OA pain and can be considered as an adjunct to core treatment for the relief of moderate to severe pain in people with OA.IA hyaluronic acid(HA)injections might have efficacy and might provide pain reduction in mild OA of knee up to 24 wk.But for HA injections,the costeffectiveness is an important concern that patients must be informed about the efficacy of these preparations.Although more high-quality evidence is needed,recent studies indicate that IA platelet rich plasma injections are promising for relieving pain,improving knee function and quality of life,especially in younger patients,and in mild OA cases.The current literature and our experience indicate that IA injections are safe and have positive effects for patient satisfaction.But,there is no data that any of the IA injections will cause osteophytes to regress or cartilage and meniscus to regenerate in patients with substantial and irreversible bone and cartilage damage.

Early therapeutic effect of platelet-rich fibrin combined with allogeneic bone marrow-derived stem cells on rats’ critical-sized mandibular defects

BACKGROUND Critically sized bone defects represent a significant challenge to orthopaedic surgeons worldwide.These defects generally result from severe trauma or resection of a whole large tumour.Autologous bone grafts are the current gold standard for the reconstruction of such defects.However,due to increased patient morbidity and the need for a second operative site,other lines of treatment should be introduced.To find alternative unconventional therapies to manage such defects,bone tissue engineering using a combination of suitable bioactive factors,cells,and biocompatible scaffolds offers a promising new approach for bone regeneration.AIM To evaluate the healing capacity of platelet-rich fibrin(PRF)membranes seeded with allogeneic mesenchymal bone marrow-derived stem cells(BMSCs)on critically sized mandibular defects in a rat model.METHODS Sixty-three Sprague Dawley rats were subjected to bilateral bone defects of critical size in the mandibles created by a 5-mm diameter trephine bur.Rats were allocated to three equal groups of 21 rats each.Group I bone defects were irrigated with normal saline and designed as negative controls.Defects of group II were grafted with PRF membranes and served as positive controls,while defects of group III were grafted with PRF membranes seeded with allogeneic BMSCs.Seven rats from each group were killed at 1,2 and 4 wk.The mandibles were dissected and prepared for routine haematoxylin and eosin(HE)staining,Masson's trichrome staining and CD68 immunohistochemical staining.RESULTS Four weeks postoperatively,the percentage area of newly formed bone was significantly higher in group III(0.88±0.02)than in groups I(0.02±0.00)and II(0.60±0.02).The amount of granulation tissue formation was lower in group III(0.12±0.02)than in groups I(0.20±0.02)and II(0.40±0.02).The number of inflammatory cells was lower in group III(0.29±0.03)than in groups I(4.82±0.08)and II(3.09±0.07).CONCLUSION Bone regenerative quality of critically sized mandibular bone defects in rats was better promoted by PRF membranes seeded with BMSCs than with PRF membranes alone.

Single-and double-dose of platelet-rich plasma versus hyaluronic acid for treatment of knee osteoarthritis: A randomized controlled trial

BACKGROUND Platelet-rich plasma(PRP)and hyaluronic acid have been shown to be useful in the treatment of knee osteoarthritis.However,investigations comparing the efficacy of these two drugs together are insufficient.AIM To compare the outcomes of PRP vs hyaluronic acid injections in three groups of patients with bilateral knee osteoarthritis.METHODS This randomized controlled trial study involved 95 patients.Thirty-one subjects received a single injection of PRP(group PRP-1),33 subjects received two injections of PRP at an interval of 3 wk(group PRP-2)and 31 subjects received three injections of hyaluronic acid at 1-wk intervals(group hyaluronic acid).The patients were investigated prospectively at the enrollment and at 4-,8-and 12-wk follow-up with the Western Ontario and McMaster Universities Arthritis Index(WOMAC)and Visual Analogue Scale questionnaires.RESULTS Percentages of patients experiencing at least a 30%decrease in the total score for the WOMAC pain subscale from baseline to wk 12 of the intervention were 86%,100%and 0%in the groups PRP-1,PRP-2 and hyaluronic acid,respectively(P<0.001).The mean total WOMAC scores for groups PRP-1,PRP-2 and hyaluronic acid at baseline were 63.71,61.57 and 63.11,respectively.The WOMAC scores were significantly improved at final follow-up to 42.5,35.32 and 57.26,respectively.The highest efficacy of PRP was observed in both groups at wk 4 with about 50%decrease in the symptoms compared with about 25%decrease for hyaluronic acid.Group PRP-2 had higher efficacy than group PRP-1.No major adverse effects were found during the study.CONCLUSION PRP is a safe and efficient therapeutic option for treatment of knee osteoarthritis.It was demonstrated to be significantly better than hyaluronic acid.We also found that the efficacy of PRP increases after multiple injections.

Subtenon Injection of Autologous Platelet-Rich Plasma in Retinitis Pigmentosa: Is It a New Therapeutic Option?

Purpose: Growth factors (GFs) and neurotrophins can decelerate retinal degeneration. This study aimed to investigate the safety, efficacy and durability of subtenon injections of autologous platelet-rich plasma (aPRP) which is a rich source of GFs in retinitis pigmentosa (RP) patients. Methods: 154 eyes of 77 RP patients with various degrees of narrowed visual field were investigated in this study. Each patient received three injections with 4-week intervals and followed for at least 12 months. The examinations and the tests were obtained before the injection, 1 month after the third injection and every 3 months during the study. The primary aim was to evaluate the effects of aPRP on visual acuity (VA) and visual functions, the second aim was to estimate the duration of the therapy effect and the need for additional aPRP injection. Results: Median age of the 77 RP patients was 35.2 ± 13.9 years. All of the eyes received 3 monthly bilateral subtenon aPRP injections. Of these patients 26 received an additional one, 12 received additional two and 1 patient received additional 3 injections with 3-month interval. There were no significant ocular or systemic side effects. The mean baseline VA was 0.22 ± 0.18 Snellen lines. It improved to 0.31 ± 0.19 following three aPRP injections, which was statistically significant. At the end of the study period, the mean VA was 0.27 ± 0.22 Snellen lines. Conclusion: The subtenon injection of aPRP might be an effective therapy and might have a positive influence in the preservation of visual functions and visual acuity of RP patients.

Effect of Bismuth Subgallate/Borneol Combined with Autologous Platelet-Rich Gel in the Treatment of Patients with Diabetic Foot Ulcers

Objective: To explore the effect of Bismuth Subgallate/Borneol (SuileTM BSB) healing dressing combined with autologous platelet-rich gel (APG) in the treatment of diabetic foot ulcer (DFU). Methods: A total of 120 patients with DFU hospitalized in the Changsha Central Hospital from August 2020 to September 2021 were selected and randomly divided into an experimental group (BSB + APG, n = 60) and a control group (BSB, n = 60) according to random number table method. The total therapeutic effect, healing time, hospital stay, level indexes of various inflammatory factors before and after treatment and ulcer area were observed in the two groups. Results: The total effect of the control group was worse than that of the experimental group, and the data between the two groups were significant (P 0.05);after treatment, the levels of inflammatory factors including WBC, CRP, IL-6 and TNF-α in the control group were higher than those in the experimental group, and there was significant difference between the two groups (P 0.05);after 14 days of treatment, the ulcer area in the control group was larger than that in the experimental group, and the data between the two groups were significant (P Conclusion: BSB combined with APG can achieve better therapeutic effect, reduce the inflammatory reaction of patients, and promote wound healing in the treatment of patients with diabetic foot ulcer.

The Role of Leukocyte and Platelet-Rich Fibrin in Enhancing the Healing of Extraction Sockets: An Overview of the Literature

Introduction: Leukocyte and platelet-rich fibrin (L-PRF) is an emerging material in dentistry, however, there are controversies surrounding its effectiveness. Despite the amount of literature available, debates regarding its effect continue. This review aims to summarize and clarify the data surrounding the use of L-PRF in promoting the healing of extraction sockets, which may offer a better outcome for future treatments. Purpose: The purpose of this review is to evaluate the current literature on the use of L-PRF in promoting the healing of extraction sockets, and to provide a comprehensive overview of the available evidence. Methods: A comprehensive computer-based search of databases such as PubMed, Medline, and Cochrane Library was conducted. Results: The results of this review suggest that L-PRF has shown promise in promoting early healing of extraction sockets, but the evidence for its effectiveness over a longer period is limited. Conclusion: Although L-PRF has shown promising results in the early healing periods, its effectiveness over a longer healing period cannot be confirmed based on the available data. More clinical trials with standardized protocols and consistent measurement methods are needed to establish the role of L-PRF in enhancing the healing of extraction sockets.

Effectiveness of a Single High Dose of Platelet-Rich Plasma (PRP) Injection Over Corticosteroid and Hyaluronic Acid Injections on Osteoarthritis, Chronic Tendinitis and Tennis Elbow Treatment

Background: Corticosteroid, hyaluronic acid (HA) injections and Anti-inflammatory agents are considered as non-invasive treatments for knee osteoarthritis (OA), Chronic Tendinitis (CT) and Tennis elbow (TE) that are supposed to provide symptomatic relief and to help surgical delay intervention. Platelet rich plasma (PRP) is a biological component shown to be beneficial for different orthopedic dysfunctionalities treatment. The presence of GFs in PRPs such as transforming growth factor-β, insulin-like growth factor 1co-stimulate the mesenchymal stem cells and fibroblasts secretions and promotes the fibrin matrix formation which effectively drive the healing process, induces regenerative response and lead to the damage structure repair in orthopedics trauma. Methods: Three groups of a total of 30 patients presenting OA, CT and TE diagnosis, non-responding to corticosteroid, HA and non-steroid anti-inflammatory treatments were randomized to undergo one intra-articular injections of single high dose of PRP. The efficacy of Intra-articular PRP Injections was evaluated before the injection and one month after. The efficiency assessment score was based on [1] Knee injury and Osteoarthritis Outcome Score, [2] Physical Function Short Form (KOOS-PS) Arabic (KSA) version LK 1.0, [3] HOOS-Physical Function Short form (HOOS-PS), and [4] Macdermid patient-rated Tennis Elbow. Results: A significant reduction of pain and a marked improvement in movements was observed in the 3 patient’s groups, PRP-injected patients showed significantly higher values compared with baseline: (p < 0.005 vs baseline), improve functional status and reduce clearly the articular dysfunctions over the time. In our study, single High dose injection of PRP provided an overall superior clinical improvement compared with HA and corticosteroid treatments over the time and the different follow-up checkpoints of the study.

Carboxytherapy and Platelet Rich Plasma： A New Therapy for Trigonitis, Abacterial and Interstitial Cystitis

Cystitis often appears even in absence of bacteria colonization. Trigonitis and interstitial inflammation are the most common morphological features of abacterial cystitis in young and post menopausal women. Arterial obstructive disease and bladder ischemia might play an important role in bladder dysfunction. Activated inflammatory cells produce ROS （radicals of oxygen）, NF kB seems involved in ROS synthesis. Clinical studies have indicated that high CO2 levels can impact upon peripheral tissue, reducing ischaemia, responsible of recurrent inflammation and consequently reducing oxydative phenomena. PRP （platelet-rich plasma） is a volume of fractionated plasma from the patient＇s own blood that contains platelet concentrate rich of alpha granules. PRP interacts tissue repair mechanisms by placing supra-physiological concentrations of autologous platelets at the site of tissue damage. This study proposes a single PRP transvaginal injection followed by 10 weekly applications of carboxytherapy, using subcutaneous injections of sterile CO2 gas. We have selected 6 Women （50-75 years）, affected by recurrent abacterial cystitis with Pain and urge incontinence. All patients showed a subjective sensible reduction of symptoms. After 2 months all patients have neither inflammatory symptoms nor endoscopic evidence of trigonitis. Preliminary qualitative results could encourage the use of carboxytherapy and PRP in treatment of abacterial and interstitial cystitis.

Experimental substantiation of the platelet-rich plasma usage in toxic hepatitis treatment

The paper presents the investigation of the possibility of hepatic tissue restoration by the platelet-rich plasma(PRP)in case of toxic hepatitis.It is shown PRP injection into liver reduced an amount of connective tissue and collagen fibers at the places of hepatocytes necrosis after experimental toxic influence.PRP administration leads to rapid regeneration of hepatic tissues with restoration of its normal structure.As PRP is concentrate of autologous blood cells,it doesn't cause any side effects and doesn't require immunosuppressive therapy.

Evaluating the Benefits of Platelet Rich-Fibrin in Periodontal Regeneration: A Literature Review

Introduction: Platelet Rich-Fibrin (PRF) is a biological matrix derived from a patient’s own blood, rich in growth factors and platelets. Its use in various periodontal and non-periodontal procedures is gaining recognition due to its potential in promoting tissue regeneration. The purpose of this review was to evaluate the benefits of using PRF in intra-bony defect regeneration, guided-bone regeneration, and sinus floor elevation. Methods: The study searched PubMed for manuscripts published between 2017 and 2022 to better understand the clinical and radiological effects of PRF. The manuscripts were divided into the following sections: intra-bony defect regeneration, guided-bone regeneration, and sinus floor elevation. Results: In intra-bony defects, PRF improved clinical and radiological parameters when compared with OFD alone, with a significant difference in wound healing at 7 days. In GBR, a CBCT evaluation shows no statistical difference between the PRF-autogenous bone complex group and the bovine bone-collagen membrane complex regarding volume change of the augmented bone with a 16% rate of bone loss following a 6-month healing period. Also, a slight increase in bone thickness has been seen when liquid PRF is used. In sinus floor elevation, results revealed no differences in graft volume between PRF group and control group at any of the evaluated time points. Although higher implant stability immediately postoperatively, higher new bone formation, the lesser amount of residual graft and earlier implant placement. Conclusion: Platelet Rich-Fibrin is widely accepted for use in periodontal surgery and dentistry due to its minimally invasive nature and low risk of adverse effects, with positive results in tissue regeneration. There is evidence that PRF leads to improved and faster healing, as well as cost-effective regenerative procedures compared to other treatments.

Intra-Articular Autologous Platelet-Rich Plasma Hip Injection May Result in Osteogenesis Depicted as an Increase in Femoral Neck Bone Density

Osteoporosis has become one of the most prevalent bone diseases in developed countries. As the world’s population ages, this complex skeletal disorder is predicted to become an even more widespread and serious health condition, posing greater societal economic burden. Current therapeutic agents are limited by clinically significant side effects. In this report, we present a case that suggests intra-articular platelet-rich plasma (PRP) injectate may improve bone mineral density (BMD). This observation raises a question with exciting implications—can PRP serve as a viable and relatively safe, targeted treatment option to improve bone density?

Evaluating the Effects on Ultrasound and on Magnetic Resonance for Knee Osteoarthritis Treatment by Platelet Rich Plasma Therapy in Combination with Mesenchymal Stem Cells from Autologous Adipose Tissue

Aim: To evaluate the effects based the changes on ultrasound and on magnetic resonance for knee osteoarthritis treatment by platelet-rich plasma therapy in combination with mesenchymal stem cell from autologous adipose tissue. Objects and Methods: 30 patients, 26 females, 4 males, mean age 58.63 ± 11.11, mean disease duration 5.3 ± 4.6 years, respectively 60 knee joints were diagnosed with osteoarthritis at stage II - III according to the Kellgren and Lawrence classifications. After ultrasound and magnetic resonance imaging in the first time, all patients were injected with platelet-rich plasma combined with mesenchymal stem cells from autologous adipose tissue into both knee joints. Results: After treatment 12 months by platelet-rich plasma injection combined with mesenchymal stem cells from autologous adipose tissue: The thickness of articular cartilage on ultrasound increased significantly from 2.08 ± 0.36 mm to 2.48 ± 0.36 mm with p Conclusion: The treatment of knee osteoarthritis by platelet-rich plasma combined with mesenchymal stem cells from autologous adipose tissue was effective in improving cartilage thickness on ultrasound and magnetic resonance, thereby improving the motor function of the knee joint.

Clinical and Magnetic Resonance Image Changes of Platelet-Rich Plasma Therapy in Combination with Human Mesenchymal Stem Cells from Autologous Adipose Tissue for Knee Osteoarthritis Treatment

Objective: To evaluate the efficacy based on clinical symptom and on magnetic resonance image of platelet-rich plasma therapy in combination with mesenchymal stem cells from autologous adipose tissue for knee osteoarthritis treatment. Patients and Method: 30 patients including 26 females and 4 males;correspondingly, 60 knee joints were diagnosed with osteoarthritis with stages II - III of Kellgren and Lawrence, their mean age was 58.63 ± 11.11. All were injected with autologous platelet-rich plasma that was extracted by PRP set, APC 30 PRP PRCEDURE PRAK and autologously extracted mesenchymal stem cells from abdominal adipose tissue using the ADI-25-01 ADIPOSEPRCEDURE PRAK of USA. Results: After 12 months: the pain level according to VAS score at the right knee joint was decreased from 6.0 ± 1.28 before treatment to 1.9 ± 0.3;VAS score at the left knee joint was decreased from 6.43 ± 1.19 to 2.25 ± 0.43. Total Lequene score at right knee joint was decreased from 16.04 ± 1.57 before treatment to 4.31 ± 1.04, at left knee joint was decreased from 17.52 ± 1.74 before treatment to 5.15 ± 1.48. Total WOMAC score at right knee joint was decreased from 55.93 ± 5.56 to 10.37 ± 1.56;at left knee joint was decreased from 53.97 ± 5.57 to 10.07 ± 1.59. There were 86.77% joints with cartilage thickness change and the patellar cartilage thickness was increased from 1.56 ± 0.09 mm before treatment to 1.65 ± 0.09 mm. Conclusion: The treatment of knee osteoarthritis by platelet-rich plasma therapyin combination with mesenchymal stem cells from autologous adipose tissue is effective in reducing pain, improving patient's mobility and walking function, reforming articular cartilage thickness on magnetic resonance image.

Autologous peripheral blood-derived orthobiologics:Different types and their effectiveness in managing knee osteoarthritis

Knees are the most commonly impacted weight-bearing joints in osteoarthritis(OA),affecting millions of people worldwide.With increasing life spans and obesity rates,the incidence of knee OA will further increase,leading to a significant increase in the economic burden.Conventional treatment modalities utilized to manage knee OA have limitations.Over the last decade,the role of various autologous peripheral blood-derived orthobiologics(APBOs)for the treatment of knee OA has been extensively investigated.This editorial provided an overview and focused on defining and shedding light on the current state of evidence based on the most recent published clinical studies concerning the use of APBO for the management of knee OA.While numerous studies have demonstrated promising results for these preparations,a notable gap exists in the comparative analysis of these diverse formulations.This absence of head-to-head studies poses a considerable challenge for physicians/surgeons in determining the optimal preparation for managing knee OA and achieving sustained longterm results.Thus,more adequately powered,multicenter,prospective,doubleblind,randomized controlled trials with longer follow-ups are needed to establish the long-term efficacy and to aid physicians/surgeons in determining the optimal APBO for the management of knee OA.

Antibacterial effects of platelet-rich fibrin produced by horizontal centrifugation

Platelet-rich fibrin(PRF)has been widely used owing to its ability to stimulate tissue regeneration.To date,few studies have described the antibacterial properties of PRF.Previously,PRF prepared by horizontal centrifugation(H-PRF)was shown to contain more immune cells than leukocyte-and platelet-rich fibrin(L-PRF).This study aimed to compare the antimicrobial effects of PRFs against Staphylococcus aureus and Escherichia coli in vitro and to determine whether the antibacterial effects correlated with the number of immune cells.Blood samples were obtained from eight healthy donors to prepare L-PRF and H-PRF.The sizes and weights of L-PRF and H-PRF were first evaluated,and their antibacterial effects against S.aureus and E.coli were then tested in vitro using the inhibition ring and plate-counting test methods.Flow-cytometric analysis of the cell components of L-PRF and H-PRF was also performed.No significant differences in size or weight were observed between the L-PRF and H-PRF groups.The H-PRF group contained more leukocytes than the L-PRF group.While both PRFs had notable antimicrobial activity against S.aureus and E.coli,H-PRF demonstrated a significantly better antibacterial effect than L-PRF.Furthermore,the antimicrobial ability of the PRF solid was less efficient than that of wet PRF.In conclusion,H-PRF exhibited better antibacterial activity than L-PRF,which might have been attributed to having more immune cells.

Platelet-rich plasma for muscle injuries: A systematic review of the basic science literature

BACKGROUND Platelet-rich plasma(PRP) is an increasingly used biologic adjunct for muscle injuries, as it is thought to expedite healing. Despite its widespread use, little is known regarding the mechanisms by which PRP produces its efficacious effects in some patients.AIM To clarify the effects of PRP on muscular pathologies at the cellular and tissue levels by evaluating the basic science literature.METHODS A systematic review of PubMed/MEDLINE and EMBASE databases was performed using the Preferred Reporting Items for Systematic Reviews and MetaAnalyses(PRISMA) guidelines and checklist. Level III in vivo and in vitro studies examining PRP effects on muscles, myocytes and/or myoblasts were eligible for inclusion. Extracted data included PRP preparation methods and study results.RESULTS Twenty-three studies were included(15 in vivo, 6 in vitro, 2 in vitro/in vivo). Only one reported a complete PRP cytology(platelets, and red and white blood cell counts). Five in vitro studies reported increased cellular proliferation, four reported increased gene expression, and three reported increased cellular differentiation. Five in vivo studies reported increased gene expression, three reported superior muscle regeneration, and seven reported improved histological quality of muscular tissue.CONCLUSION The basic science literature on the use of PRP in muscle pathology demonstrates that PRP treatment confers several potentially beneficial effects on healing in comparison to controls. Future research is needed to determine optimal cytology,dosing, timing, and delivery methods of PRP for muscle pathologies.

Platelet-rich plasma increases transforming growth factor-beta1 expression at graft-host interface following autologous osteochondral transplantation in a rabbit model

AIM: To explore the effect of platelet-rich plasma on protein expression patterns of transforming growth factor-beta1(TGF-β1) in cartilage following autologous osteochondral transplantation(AOT) in a rabbit knee cartilage defect model.METHODS: Twelve New Zealand white rabbits received bilateral AOT. In each rabbit, one knee was randomized to receive an autologous platelet rich plasma(PRP) injection and the contralateral knee received saline injection. Rabbits were euthanized at 3, 6 and 12 wk post-operatively. Articular cartilage sections were stained with TGF-β1 antibody. Histological regions of interest(ROI)(left, right and center of the autologous grafts interfaces) were evaluated using Meta Morph. Percentage of chondrocytes positive for TGF-β1 was then assessed.RESULTS: Percentage of chondrocytes positive for TGF-β1 was higher in PRP treated knees for selected ROIs(left; P = 0.03, center; P = 0.05) compared to control and was also higher in the PRP group at each post-operative time point(P = 6.6 × 10^(-4), 3.1 × 10^(-4) and 7.3 × 10^(-3) for 3, 6 and 12 wk, respectively). TGF-β1 expression was higher in chondrocytes of PRP-treated knees(36% ± 29% vs 15% ± 18%)(P = 1.8 × 10^(-6)) overall for each post-operative time point and ROI. CONCLUSION: Articular cartilage of rabbits treated with AOT and PRP exhibit increased TGF-β1 expression compared to those treated with AOT and saline. Our findings suggest that adjunctive PRP may increase TGF-β1 expression, which may play a role in the chondrogenic effect of PRP in vivo.

Platelet-rich plasma gel in combination with Schwann cells for repair of sciatic nerve injury

Bone marrow mesenchymal stem cells were isolated from New Zealand white rabbits, culture-expanded and differentiated into Schwann cell-like cells. Autologous platelet-dch plasma and Schwann cell-like cells were mixed in suspension at a density of 1 x 106 cells/mL, prior to introduction into a poly （lactic-co-glycolic acid） conduit. Fabricated tissue-engineered nerves were implanted into rabbits to bridge 10 mm sciatic nerve defects （platelet-rich plasma group）. Controls were established using fibrin as the seeding matrix for Schwann cell-like cells at identical density to construct tissue-engineered nerves （fibrin group）. Twelve weeks after implantation, toluidine blue staining and scanning electron microscopy were used to demonstrate an increase in the number of regenerating nerve fibers and thickness of the myelin sheath in the platelet-rich plasma group compared with the fibrin group. Fluoro-gold retrograde labeling revealed that the number of Fluoro-gold-positive neurons in the dorsal root ganglion and the spinal cord anterior horn was greater in the platelet-rich plasma group than in the fibrin group. Electrophysiological examination confirmed that compound muscle action potential and nerve conduction velocity were superior in the platelet-rich plasma group compared with the fibrin group. These results indicate that autologous platelet-rich plasma gel can effectively serve as a seeding matrix for Schwann cell-like cells to construct tissue-engineered nerves to promote perJpheral nerve regeneration.

Platelet-rich fibrin-induced bone marrow mesenchymal stem cell differentiation into osteoblast-like cells and neural cells

Bone marrow mesenchymal stem cells were allowed to develop for 14 days in a platelet-rich fibrin environment.Results demonstrated that platelet-rich fibrin significantly promoted bone marrow mesenchymal stem cell proliferation.In addition,there was a dose-dependent increase in Runt-related transcription factor-2 and bone morphogenetic protein-2 mRNA expression,as well as neuron-specific enolase and glial acidic protein.Results showed that platelet-rich fibrin promoted bone marrow mesenchymal stem cell proliferation and differentiation of osteoblast-like cells and neural cells in a dose-dependent manner.