Current Progress of Platelet-Rich Derivatives in Cartilage and Joint Repairs

Cartilage repair: unleashing PRP's potential in organoid models

Platelet-rich plasma (PRP) has emerged as a promising biological therapy in regenerative medicine due to its high concentration of growth factors and cytokines, which promote tissue healing and regeneration. In recent years, its application in cartilage tissue engineering has garnered significant attention. This study explores the synergistic interaction between PRP and cartilage organoids, a novel three-dimensional in vitro culture system that closely mimics the structural and functional properties of native cartilage. Cartilage organoids serve as a physiologically relevant model for studying cartilage development, disease progression, and regeneration. By integrating PRP with cartilage organoids, this review aims to enhance chondrogenesis, extracellular matrix synthesis, and cellular proliferation within the organoids. Emerging evidence suggests that PRP supplementation significantly improves chondrocyte viability, growth, and differentiation in cartilage organoids, thereby accelerating their maturation. This combination holds great potential for advancing cartilage repair strategies, providing a robust platform for preclinical studies, and paving the way for innovative therapeutic approaches for cartilage-related injuries and degenerative diseases. These key aspects-chondrogenesis, matrix synthesis, and cellular proliferation-were specifically selected due to their fundamental roles in cartilage tissue engineering and regeneration. Chondrogenesis is crucial for chondrocyte differentiation and maintenance, matrix synthesis ensures the structural integrity and functional properties of regenerated cartilage, and cellular proliferation supports tissue viability and repair. Addressing these factors is essential, as current cartilage regeneration strategies often suffer from limited long-term efficacy and inadequate extracellular matrix production. By elucidating the synergistic effects of PRP and cartilage organoids in these areas, this study seeks to bridge existing knowledge gaps and provide valuable insights for improving regenerative approaches in clinical applications, particularly for osteoarthritis and cartilage defects.

Current trends in the design and fabrication of PRP-based scaffolds for tissue engineering and regenerative medicine

Blood-derived biomaterials with high platelet content have recently emerged as attractive products for tissue engineering and regenerative medicine (TERM). Platelet-derived bioactive molecules have been shown to play a role in wound healing and tissue regeneration processes by promoting collagen synthesis, angiogenesis, cell proliferation, migration, and differentiation. Given their regenerative potential, platelet-rich blood derivatives have become a promising treatment option for use in a variety of conditions. Platelet-Rich Plasma (PRP), one of the platelet-rich blood derivatives, is a platelet concentrate suspended in a small volume of blood plasma obtained from whole blood. Due to its potential clinical benefits, PRP is widely used alone or in combination with various biomaterials/scaffolds in different fields of medicine and has shown promising results in wound healing. The recent growing interest in the development of PRP-based scaffolds also reveals new perspectives on the use of PRP or platelet lysate in TERM. This topical review contains a comprehensive summary of recent trends in the fabrication of PRP-based scaffolds that can deliver growth factors, serve as mechanical support for cells, and have therapeutic or regenerative properties. The article briefly focuses on diverse PRP-based constructs using PRP as a scaffolding material, their current fabrication approaches as well as the challenges encountered and provides a selection of existing strategies and new insights.

Platelet-rich fibrin in the management of oral mucosal lesions: a scoping review

OBJECTIVES

Oral mucosal lesions are prevalent and often cause pain, thus impacting patients' quality of life. Platelet-rich fibrin (PRF) has emerged as a promising autologous biomaterial for wound healing, yet comprehensive evidence regarding its efficacy in treating oral mucosal lesions is limited. This study aims to update the current evidence on the effectiveness of PRF in treating various types of oral mucosal lesions.

MATERIALS AND METHODS

We conducted a literature search in PubMed, Scopus, Embase, and Web of Science databases until April 2024. The search included studies that investigated the use of PRF in treating oral mucosal lesions. Twelve studies met the inclusion criteria, comprising three case reports, three randomized controlled trials, two animal studies, three split-mouth trials, and one retrospective study. We performed data extraction according to a predefined form.

RESULTS

PRF was applied in two forms-membranes and injectable gels-to treat a range of oral mucosal lesions, including ulcerative, red and white, pigmented, and potentially malignant or malignant lesions. Compared to control groups or conventional treatments, PRF generally demonstrated superior outcomes regarding faster healing, lesion size reduction, symptom relief, and lower recurrence rates. Histological and molecular analyses from some studies also indicated PRF's regenerative and anti-inflammatory effects.

CONCLUSION

PRF shows promise as an effective and safe alternative to current treatments for oral mucosal lesions due to its autologous nature, ease of preparation, and wound-healing capabilities. However, further research is needed to standardize PRF preparation protocols and confirm its long-term efficacy across different lesion types.

Developing fibrin-based biomaterials/scaffolds in tissue engineering

Tissue engineering technology has advanced rapidly in recent years, offering opportunities to construct biologically active tissues or organ substitutes to repair or even enhance the functions of diseased tissues and organs. Tissue-engineered scaffolds rebuild the extracellular microenvironment by mimicking the extracellular matrix. Fibrin-based scaffolds possess numerous advantages, including hemostasis, high biocompatibility, and good degradability. Fibrin scaffolds provide an initial matrix that facilitates cell migration, differentiation, proliferation, and adhesion, and also play a critical role in cell-matrix interactions. Fibrin scaffolds are now widely recognized as a key component in tissue engineering, where they can facilitate tissue and organ defect repair. This review introduces the properties of fibrin, including its composition, structure, and biology. In addition, the modification and cross-linking modes of fibrin are discussed, along with various forms commonly used in tissue engineering. We also describe the biofunctionalization of fibrin. This review provides a detailed overview of the use and applications of fibrin in skin, bone, and nervous tissues, and provides novel insights into future research directions for clinical treatment.

Biomimetic design of platelet-rich plasma controlled release bacterial cellulose/hydroxyapatite composite hydrogel for bone tissue engineering

Bacterial cellulose (BC) hydrogel is renowned in the field of tissue engineering for its high biocompatibility, excellent mechanical strength, and eco-friendliness. Herein, we present a biomimetic mineralization method for preparing BC/hydroxyapatite (HAP) composite hydrogel scaffolds with different mineralization time and ion concentration of the mineralized solution. Spherical HAP reinforcement enhanced bone mineralization, thereby imparting increased bioactivity to BC matrix materials. Subsequently, platelet-rich plasma (PRP) was introduced into the scaffold. The PRP-loaded hydrogel enhanced the release of growth factors, which promoted cell adhesion, growth, and bone healing. After 3 weeks of MC3T3-E1 cell-induced osteogenesis, PRP positively affected cell differentiation in BC/HAP@PRP scaffolds. Overall, these scaffolds exhibited excellent biocompatibility, mineralized nodule formation, and controlled release in vitro, demonstrating great potential for application in bone tissue repair.

Clinical evaluation of platelet-rich plasma therapy for osteonecrosis of the femoral head: A systematic review and meta-analysis

OBJECTIVE

This meta-analysis aims to assess the efficacy and safety of platelet-rich plasma (PRP) for osteonecrosis of the femoral head (ONFH).

METHODS

We comprehensively searched randomized controlled trials in PubMed, Web of Science, EMBASE, the Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure, China Science and Technology Journal Database, WanFang, and Chinese BioMedical Literature Database from inception until October 25, 2024. The literature on the clinical efficacy of autologous PRP for ONFH was collated. According to the inclusion and exclusion criteria, the literature was screened, quality evaluated and the data was extracted. Meta-analysis was carried out with the software Review Manager 5.4.1 software and Stata 17.0 software. In addition, potential publication bias was detected by the funnel plot test and Egger's test. The GRADE system was used to evaluate the quality of evidence for outcome indicators.

RESULTS

Fourteen studies involving 909 patients were included in this study. Compared with non-PRP, PRP exhibited significant improvements in the Harris hip score (HHS) at 3 months (MD = 3.58, 95% Cl: 1.59 to 5.58, P = 0.0004), 6 months (MD = 6.19, 95% Cl: 3.96 to 8.41, P < 0.00001), 12 months (MD = 4.73, 95% Cl: 3.24 to 6.22, P < 0.00001), ≥ 24 months (MD = 6.83, 95% Cl: 2.09 to 11.59, P = 0.0003), and the last follow-up (MD = 6.57, 95% Cl: 4.81 to 8.33, P < 0.00001). The PRP also showed improvement in HHS compared to baseline than the non-PRP at 3 months (MD = 3.60, 95% Cl: 1.26 to 5.94, P = 0.003), 6 months (MD = 6.17, 95% Cl: 3.74 to 8.61, P < 0.00001), 12 months (MD = 5.35, 95% Cl: 3.44 to 7.25, P < 0.00001), ≥ 24 months (MD = 8.19, 95% Cl: 3.76 to 12.62, P = 0.0003), and the last follow-up (MD = 6.94, 95% Cl: 5.09 to 8.78, P < 0.00001). The change in visual analog scale (VAS) score 3 months post intervention (MD = -0.33, 95% Cl: -0.52 to -0.13, P = 0.001), 6 months (MD = -0.69, 95% Cl: -0.90 to -0.48, P < 0.00001), 12 months (MD = -0.75, 95% Cl: -1.05 to -0.46, P < 0.00001), ≥ 24 months (MD = -1.05, 95% Cl: -1.20 to -0.89, P < 0.00001), and the last follow-up (MD = -0.75, 95% Cl: -0.97 to -0.54, P < 0.00001). The PRP also showed a decrease in VAS score compared to baseline than the non-PRP at 3 months (MD = -0.29, 95% Cl: -0.41 to -0.17, P = 0.003), 6 months (MD = -0.63, 95% Cl: -0.96 to -0.30, P = 0.0002), 12 months (MD = -0.78, 95% Cl: -1.22 to -0.33, P = 0.0006), ≥ 24 months (MD = -1.11, 95% Cl: -1.27 to -0.96, P < 0.00001), and the last follow-up (MD = -0.74, 95% Cl: -1.05 to -0.43, P < 0.00001). Additionally, it was found that the PRP group had the advantages in the following aspects: collapse rate of the femoral head (RR = 0.33, 95% Cl: 0.17 to 0.62, P = 0.0006), rate of conversion to total hip arthroplasty (RR = 0.37, 95% Cl: 0.18 to 0.74, P = 0.005), and overall complications (RR = 0.33, 95% Cl: 0.13 to 0.83, P = 0.02). The GRADE evidence evaluation showed overall complication as very low quality and other indicators as low quality.

CONCLUSION

There is limited evidence showing benefit of PRP therapy for treatment of ONFH patients, and most of this evidence is of low quality. Caution should therefore be exercised in interpreting these results. It is recommended that future research involve a greater number of high-quality studies to validate the aforementioned conclusions.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/ #recordDetails, CRD42023463031.

Human versus Rat PRF on Collagen Membranes: A Pilot Study of Mineralization in Rat Calvaria Defect Model

Platelet-rich fibrin, the coagulated plasma fraction of blood, is commonly used to support natural healing in clinical applications. The rat calvaria defect is a standardized model to study bone regeneration. It remains, however, unclear if the rat calvaria defect is appropriate to investigate the impact of human PRF (Platelet-Rich Fibrin) on bone regeneration. To this end, we soaked Bio-Gide® collagen membranes in human or rat liquid concentrated PRF before placing them onto 5 mm calvarial defects in Sprague Dawley rats. Three weeks later, histology and micro-computed tomography (μCT) were performed. We observed that the collagen membranes soaked with rat PRF show the characteristic features of new bone and areas of mineralized collagen matrix, indicated by a median mineralized volume of 1.5 mm3 (range: 0.9; 5.3 mm3). Histology revealed new bone growing underneath the membrane and hybrid bone where collagen fibers are embedded in the new bone. Moreover, areas of passive mineralization were observed. The collagen membranes soaked with human PRF, however, were devoid of histological features of new bone formation in the center of the defect; only occasionally, new bone formed at the defect margins. Human PRF (h-PRF) caused a median bone volume of 0.9 mm3 (range: 0.3-3.3 mm3), which was significantly lower than what was observed with rat PRF (r-PRF), with a BV median of 1.2 mm3 (range: 0.3-5.9 mm3). Our findings indicate that the rat calvaria defect model is suitable for assessing the effects of rat PRF on bone formation, but caution is warranted when extrapolating conclusions regarding the efficacy of human PRF.

Clinical observation of ultraviolet therapy combined with autologous platelet-rich plasma in the treatment of chronic refractory wounds

Refractory wounds present complex and serious clinical dilemmas in plastic and reconstructive surgeries. Currently, there are no standard guidelines for the treatment of refractory wounds. To observe the clinical effects of ultraviolet (UV) therapy combined with autologous platelet-rich plasma (PRP) on chronic refractory wounds. Between January 2021 and December 2022, 60 inpatients with chronic refractory wounds were enrolled. Twenty patients were assigned to each of control groups 1 and 2 and treatment group according to whether they received PRP or UV treatment. All the patients underwent thorough debridement. Control group 2 received UV radiation. The treatment group underwent UV radiation combined with PRP gel covering the wound. Control group 1 underwent routine dressing changes after surgery, followed by skin grafting or skin key transfer if needed. One month later, we observed the wound healing in the two groups. After 2-4 PRP gel treatments, the wounds of patients in the treatment group healed. The healing time was 25.25 ± 4.93 days, and the dressings were changed 4.15 ± 3.30 times, both of which were better outcomes than in both control groups. In the treatment group, epidermal growth factor (EGF), insulin-like growth factor (IGF), platelet-derived growth factor (PGF), and transforming growth factor β (TGF-β) were slightly higher, and the concentration of vascular endothelial growth factor (VEGF) was significantly higher than in the control group (p < 0.05). PRP combined with UV therapy significantly increased the concentration of wound growth factors, accelerated wound healing, shortened treatment time, reduced treatment costs, and alleviated pain in patients.

Autologous leucocyte and platelet rich in fibrin (L-PRF) - is it a competitive solution for bone augmentation in maxillary sinus lift? A 6-month radiological comparison between xenografts and L-PRF

Maxillary lateral sinus floor elevation, or external sinus lift, is a widespread surgical intervention in the dental field. Insertion of implants in the posterior region of the maxilla often requires reconstruction of the remaining native bone that has insufficient volume.

Background and aims

Much of the research published involves using artificial products, like xenografts and resorbable collagen membranes, after a prior Cone Beam Computer Tomography (CBCT) investigation. Nowadays, more accessible access, less financial costs, a biological approach, and faster healing are objectives that surround this procedure. Leucocytes and platelets rich in Fibrin (L-PRF) are a natural component with a high concentration of growth factors. Due to its regenerative properties and lack of complications, it is used in several medical fields, like orthopedics, dermatology, and oral surgery. This retrospective study aims to compare results in bone height and volume obtained through external sinus lift, either by using xenografts or autologous plasma rich in fibrin, by evaluating the quantity of new bone formation from a radiological point of view.

Methods

Fifty-eight Caucasian patients were included in this retrospective study; 48 were submitted to xenograft procedure, and 10 were selected for L-PRF grafting material with simultaneous implant placement. Lack of clinical and histological studies performed on patients with L-PRF surgeries limited us in choosing a larger group for the radiological analysis. CBCT evaluation was performed before surgery and 6 months after. All patients selected for the study presented good general and oral health, acute oral and sinus infections excluded; smoking and periodontal disease were also criteria of exclusion. Two operators performed the measurements in pre-established landmarks in different time frames. The two independent groups were compared with the Wilcoxon rank-sum test for quantitative data. Qualitative characteristics were described as counts and percentages. All analyses were performed in an R environment for statistical computing and graphics.

Results

Mean bone height gain in the xenograft group in the regions was as follows: 7.44 for the anterior landmark, 12.14 for the median and 8.28 for the distal. The mean group height gained for the L-PRF group was 0.1 anteriorly, -0.18 for the median measurement, and 0.23 distally. We obtained excellent overall reliability for all the height measurements between the two operators.

Conclusions

Further studies must be conducted to establish new sets of surgical protocols in case L-PRF alone is found to be a reliable, stable, biological alternative to the well-documented xenografts in external sinus lifts. Radiological results, although promising, must be further applied in long term clinical survival of the implants in the grafted sites. Also, studies combining L-PRF in conjunction with xenograft might bring improved clinical results in terms of reduced postoperative complications and accelerated healing.

Efficacy of Injectable Platelet-Rich Fibrin (I-PRF) in Managing Temporomandibular Joint Pain: A Prospective Clinical Study

BACKGROUND

Temporomandibular joint (TMJ) pain is a common condition that can significantly impact an individual's quality of life. Current treatment options often fall short of providing long-lasting relief. So, this prospective clinical study aimed to investigate the efficacy of injectable platelet-rich fibrin (I-PRF) in mitigating TMJ pain.

METHODS

A total of 68 participants, aged 18-60 years, clinically diagnosed with TMJ pain, were recruited from dental clinics and specialist referrals. Participants were randomly assigned to either the intervention group (I-PRF injections) or the control group (placebo). Primary outcome measures included TMJ pain intensity and jaw function, assessed using the Visual Analog Scale and functional examinations, respectively. Secondary outcomes comprised patient-reported outcomes (PROs) on quality of life and satisfaction. Data were collected at baseline and six, 12, and 24 weeks post intervention.

RESULTS

Baseline characteristics demonstrated successful randomization, with no significant differences in age, gender, or TMJ pain duration between groups. Post intervention, the intervention group exhibited a significant and sustained reduction in TMJ pain intensity compared to controls (p<0.001). Improvements in jaw function were also notable in the intervention group at all follow-up time points (p<0.001). PROs related to quality of life and satisfaction substantially increased in the intervention group compared to controls (p<0.001).

CONCLUSION

I-PRF demonstrated significant efficacy in reducing TMJ pain intensity, improving jaw function, and enhancing PROs. These findings support the consideration of I-PRF as a valuable therapeutic intervention for individuals with TMJ pain.

Recent Achievements in the Development of Biomaterials Improved with Platelet Concentrates for Soft and Hard Tissue Engineering Applications

Platelet concentrates such as platelet-rich plasma, platelet-rich fibrin or concentrated growth factors are cost-effective autologous preparations containing various growth factors, including platelet-derived growth factor, transforming growth factor β, insulin-like growth factor 1 and vascular endothelial growth factor. For this reason, they are often used in regenerative medicine to treat wounds, nerve damage as well as cartilage and bone defects. Unfortunately, after administration, these preparations release growth factors very quickly, which lose their activity rapidly. As a consequence, this results in the need to repeat the therapy, which is associated with additional pain and discomfort for the patient. Recent research shows that combining platelet concentrates with biomaterials overcomes this problem because growth factors are released in a more sustainable manner. Moreover, this concept fits into the latest trends in tissue engineering, which include biomaterials, bioactive factors and cells. Therefore, this review presents the latest literature reports on the properties of biomaterials enriched with platelet concentrates for applications in skin, nerve, cartilage and bone tissue engineering.

Platelet-rich fibrin in dentistry

OBJECTIVES

To review the progress of Platelet Rich Fibrin (PRF) as a biomaterial in dentistry and to highlight its promising application as a safe and biocompatible autologous platelet concentrate. Publications were searched in GeenMedical, X-mol, GoogleScholar, and PubMed from October 2024 with no language restrictions. The literature was searched for relevant databases and journals on the use of PRFs in dentistry up to October 2024, and the inclusion criteria included randomized controlled trials, clinical trials, case series, and systematic reviews.

CONCLUSION

PRF is a second-generation platelet concentrate that is sourced from oneself, has fewer adverse effects, and is simple and safe to prepare. These materials include growth factors and fibrin scaffolds, which are extensively utilized in regenerative medicine. By outlining PRF, we found that good results can be achieved when PRF is used to treat these conditions.

CLINICAL SIGNIFICANCE

The application of PRF in dentistry is widespread, particularly in periodontal soft and hard tissue regeneration, oral lichen planus, and pulpal regeneration. This article reviews the background, classification, and preparation methods of PRFs, along with their dental applications. We anticipate further research on various PRF derivatives in the future, which will significantly improve the utilization of PRF in oral applications and offer fresh insights for diagnosing and treating oral diseases.

Platelet Concentrates Preconditioning of Mesenchymal Stem Cells and Combined Therapies: Integrating Regenerative Strategies for Enhanced Clinical Applications

This article presents a comprehensive review of the factors influencing the efficacy of mesenchymal stem cells (MSCs) transplantation and its association with platelet concentrates (PCs). It focuses on investigating the impact of PCs' composition, the age and health status of platelet donors, application methods, and environmental factors on the outcomes of relevant treatments. In addition, it delves into the strategies and mechanisms for optimizing MSCs transplantation with PCs, encompassing preconditioning and combined therapies. Furthermore, it provides an in-depth exploration of the signaling pathways and proteomic characteristics associated with preconditioning and emphasizes the efficacy and specific effects of combined therapy. The article also introduces the latest advancements in the application of biomaterials for optimizing regenerative medical strategies, stimulating scholarly discourse on this subject. Through this comprehensive review, the primary goal is to facilitate a more profound comprehension of the factors influencing treatment outcomes, as well as the strategies and mechanisms for optimizing MSCs transplantation and the application of biomaterials in regenerative medicine, offering theoretical guidance and practical references for related research and clinical practice.

The Effect of Leukocyte- and Platelet-Rich Fibrin on Central and Peripheral Nervous System Neurons-Implications for Biomaterial Applicability

Leukocyte- and Platelet-Rich Fibrin (L-PRF) is a second-generation platelet concentrate that is prepared directly from the patient's own blood. It is widely used in the field of regenerative medicine, and to better understand its clinical applicability we aimed to further explore the biological properties and effects of L-PRF on cells from the central and peripheral nervous system. To this end, L-PRF was prepared from healthy human donors, and confocal, transmission, and scanning electron microscopy as well as secretome analysis were performed on these clots. In addition, functional assays were completed to determine the effect of L-PRF on neural stem cells (NSCs), primary cortical neurons (pCNs), and peripheral dorsal root ganglion (DRG) neurons. We observed that L-PRF consists of a dense but porous fibrin network, containing leukocytes and aggregates of activated platelets that are distributed throughout the clot. Antibody array and ELISA confirmed that it is a reservoir for a plethora of growth factors. Key molecules that are known to have an effect on neuronal cell functions such as brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF), and platelet-derived growth factor (PDGF) were slowly released over time from the clots. Next, we found that the L-PRF secretome had no significant effect on the proliferative and metabolic activity of NSCs, but it did act as a chemoattractant and improved the migration of these CNS-derived stem cells. More importantly, L-PRF growth factors had a detrimental effect on the survival of pCNs, and consequently, also interfered with their neurite outgrowth. In contrast, we found a positive effect on peripheral DRG neurons, and L-PRF growth factors improved their survival and significantly stimulated the outgrowth and branching of their neurites. Taken together, our study demonstrates the positive effects of the L-PRF secretome on peripheral neurons and supports its use in regenerative medicine but care should be taken when using it for CNS applications.