Volume Of Platelet-rich Plasma Research Articles

Poster 223: Patient Reported Outcomes Following Treatment with Leukocyte Rich Platelet Rich Plasma Injections for Proximal Hamstring Tendinopathy

Poster 223: Patient Reported Outcomes Following Treatment with Leukocyte Rich Platelet Rich Plasma Injections for Proximal Hamstring Tendinopathy

An umbrella review of the use of platelet-rich plasma in the treatment of androgenetic alopecia.

To evaluate the efficacy of platelet-rich plasma (PRP) in the treatment of androgenetic alopecia, as well as establish an effective treatment protocol and optimal PRP preparation procedure. We searched the PubMed, Scopus, Embase, Cochrane, CNKI, and Wanfang databases from inception to October 29, 2021, using PROSPERO's International Prospective Register of Systematic Reviews (registration ID: CRD42022295921). The original literature search revealed 215 reviews; after duplication removal, 89 papers were eliminated, 95 were eliminated after reading the titles and abstracts, and eventually, 28 articles were included after reading the complete text. PRP treatment for androgenetic alopecia is effective, and we recommend the following: (1) a PRP volume of at least 0.05 ml/cm2 , preferably 0.1ml/cm2 ; (2) at least three consecutive treatments at an interval of 1month; (3) intensive therapy is beneficial and can be provided from 3 to 6months after continuous treatment; (4) objective indicators such as hair diameter, hair count; (5) long-term follow-up.

MP35-08 INVESTIGATION OF GROWTH FACTORS CONCENTRATION IN PLATELET RICH PLASMA (PRP) OBTAINED FROM MEN WITH ERECTILE DYSFUNCTION

You have accessJournal of UrologyCME1 May 2022MP35-08 INVESTIGATION OF GROWTH FACTORS CONCENTRATION IN PLATELET RICH PLASMA (PRP) OBTAINED FROM MEN WITH ERECTILE DYSFUNCTION Kajal Khodamoradi, Alexandra Dullea, Roei Golan, Manuel Leyba Molina, Thomas Masterson, Himanshu Arora, and Ranjith Ramasamy Kajal KhodamoradiKajal Khodamoradi More articles by this author , Alexandra DulleaAlexandra Dullea More articles by this author , Roei GolanRoei Golan More articles by this author , Manuel Leyba MolinaManuel Leyba Molina More articles by this author , Thomas MastersonThomas Masterson More articles by this author , Himanshu AroraHimanshu Arora More articles by this author , and Ranjith RamasamyRanjith Ramasamy More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002589.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Platelet Rich Plasma (PRP) is being investigated as a novel treatment option for ED. PRP is a restorative therapy rich in cytokines and growth factors that may reverse the underlying pathology of sexual dysfunction. However, before PRP can be used effectively in clinic, it is critical to understand whether the growth factor concentration is similar among men diagnosed with ED. We hypothesized that the concentration of growth factors varies in PRP’s of men with different comorbidities. Objective To determine whether growth factors vary among PRP of men with ED. METHODS: Blood was obtained from men with ED, and healthy males as controls. The Arthrex Angel system was used to extract PRP from whole blood. PRP extract was kept in −80 C. First with the Abcam Human Growth Factor Antibody Array kit (ab134002) we checked 41 human growth factors in the PRP of men with sexual dysfunction. In the next validation step, after running a Bradford Assay to ensure equal protein concentrations, we evaluated GM-CSF, VEGF, and TGF-B growth factors in an additional cohort of men with ED. The density of the bands in all the blots was analyzed using densitometry analysis with ImageJ. RESULTS: Subjects were aged 39–61 year, and all were diagnosed with ED. Subjects had a variety of additional comorbidities including obstructive sleep apnea, hyperlipidemia, and obesity. Subject BMI ranged from 20.1-32.7. The results of Human Growth factor Antibody Array showed that among 41 human growth factors in the PRP of men with sexual dysfunction, there was decreased expression of GM-CSF, VEGF, TGF-B as compared to controls. When with western blotting we validated these growth factors in an additional cohort of men with ED, we found that all these 3 growth factors were variable in their concentrations. Interestingly, we did not identify an association between growth factor expression and age, BMI, or comorbidities. CONCLUSIONS: The use of PRP as a therapeutic agent for sexual dysfunction may need to be personalized based on individuals' age, comorbidities, or growth factor content. Individuals with underlying comorbidities may need different volumes of PRP. Unlike shockwave therapy (another regenerative therapy) that can be uniformly applied to men, PRP needs to be personalized based on growth factor concentrations. Source of Funding: This work was supported by Miami CTSI Pilot Award (GR019191) to TM © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e590 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Kajal Khodamoradi More articles by this author Alexandra Dullea More articles by this author Roei Golan More articles by this author Manuel Leyba Molina More articles by this author Thomas Masterson More articles by this author Himanshu Arora More articles by this author Ranjith Ramasamy More articles by this author Expand All Advertisement PDF DownloadLoading ...

Growth Factor Concentration Can Vary in Platelet-Rich Plasma from Men with Erectile Dysfunction

ABSTRACT Introduction Erectile Dysfunction (ED) affects 40% of men over 40 and every decade after increases the likelihood by 10% (1). Platelet Rich Plasma (PRP) is a restorative therapy rich in cytokines and growth factors that may reverse the underlying pathology of ED (2). Before PRP can be used effectively in clinic, it is necessary to understand if its components are similar among men with ED. Objective To determine whether growth factors vary among PRP of men with ED Methods Blood was obtained from three men with ED and one healthy man as a control. The Arthrex Angel system was used to extract their PRP. The sample was immediately stored in ice and kept in -80 C. Bradford assay was ran to ensure equal protein concentrations were used. The Abcam Human Growth Factor Antibody Array kit (ab134002) was used to simultaneously detect 41 human growth factors. Results Subject 1 was 43 years old with ED only. Subject 2 was 43 years old with obstructive sleep apnea, hyperlipidemia, and delayed sleep phase syndrome, and BMI 27.1. Subject 3 was 49 years old with hypertension, diabetes mellitus (not on insulin), asthma, high cholesterol, and BMI 32.4.The results of evaluating the 41 growth factor array showed that several growth factors had a fold change greater than 1.5 compared to the control. In PRP of adults with ED, PDGF-AA, PDGF- AB, and PDGF-AB had a greater than 1.5-fold change in at least 2 out of the 3 samples when compared to control. In FGF-6, GM-CSF, NT-3, TGF-α, TGF-β, and TGF-β2, there was a negative fold change of greater than 1.5 in at least 2 out of the 3 samples when compared to control. Conclusions Based on these results, the use of PRP as a therapeutic agent may need to be personalized based on individuals' age, comorbidities, or growth factor content. Individuals with underlying comorbidities may need different volumes of PRP. Our future ongoing research is focusing on particular growth factors within PRP that are responsible for improvement in erectile function, thus being able to personalize PRP therapy for me with ED. Citations: 1. Feldman HA, Goldstein I, Hatzichristou DG, Krane RJ, McKinlay JB. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol. 1994;151(1):54-61. 2. Liu MC, Chang ML, Wang YC, Chen WH, Wu CC, Yeh SD. Revisiting the Regenerative Therapeutic Advances Towards Erectile Dysfunction. Cells. 2020;9(5). 3. Fang J, Huang X, Han X, Zheng Z, Hu C, Chen T, et al. Endothelial progenitor cells promote viability and nerve regenerative ability of mesenchymal stem cells through PDGF-BB/PDGFR-beta signaling. Aging (Albany NY). 2020;12(1):106-21. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Acerus Pharmaceutical

Platelet-rich plasma alleviates myocardial ischemia-reperfusion injury in rats

To investigate the protective effect of platelet-rich plasma (PRP) against acute myocardial ischemiareperfusion (IR) injury and the possible mechanism. Aortic blood samples were collected from 10 SD rats to prepare PRP, in which the concentrations of platelet-derived growth factor-BB (PDGF-BB) and transforming growth factor-β1 (TGF-β1) were measured. Cell models of IR injury were established in primary cultures of neonatal SD rat cardiomyocytes by exposing the cells to 3 h of hypoxia. The cells were then reoxygenated and co-cultured with 1%, 5%, 10%, and 20% volume of PRP for 12 h, and the changes in cell viability was assessed. Immunofluorescence staining of the cardiomyocytes was performed, and the cellular expression of AMPK and its phosphorylation level were detected. The effects of PRP on the proliferation and migration of rat aortic endothelial cells (RAOECs) were examined. In a SD rat model of myocardial IR injury, 100 μL of PRP (n= 20) or normal saline (n=20) was injected at 4 sites around the ligation site immediately after cardiac reperfusion. One day after the injection, 6 rats were selected from each group for TTC staining of the myocardial tissues and measurement of troponin Ⅰ content. One week later, the cardiac function of the remaining rats was assessed by echocardiography, and HE staining of the myocardial tissues was performed. The effect of PRP treatment for 24 h on polarization of M1 and M2 macrophages was also examined by flow cytometry in RAW264.7 cells after hypoxic exposure for 3 h. The concentrations of PDGF-BB and TGF-β1 were significantly higher in PRP than in whole blood. Addition of 1% volume of PRP significantly reduced death of the cardiomyocytes following reoxygenation, and this effect was closely related with the activation of AMPK. Treatment with PRP obviously promoted the proliferation and migration of RAOECs. In rat models of acute myocardial IR injury, injections of PRP significantly reduced the infarct size and troponin Ⅰ concentration as compared with saline injection (P < 0.001). One week after PRP injection, the rats showed significantly improved cardiac function with a lowered level of inflammatory response in comparison with the rats with saline injection. In RAW264.7 cells with hypoxic exposure, treatment with PRP obviously decreased the number of M1 macrophages and increase the number of M2 macrophages. PRP can improve acute myocardial IR injury in rats by phosphorylating AMPK and regulating macrophage polarization, which produces a protective immunomodulatory effect on the ischemic myocardial tissues.

What Is the Adequate PRP Dose for an Effective Treatment? An In Vitro Experimental Study on the Skin.

The clinical results of many studies on platelet-rich plasma (PRP) differ due to a lack of standardization in PRP preparation and administration as well as many variables such as PRP preparation methods, platelet concentration, and platelet activation. The authors sought to investigate a different variable that will affect PRP application results. How much PRP should be injected into the unit area of tissue for an effective PRP treatment? The study was performed on fresh surplus tissues of 20 patients that were discarded in abdominoplasty and mammoplasty operations. Nine areas of 4 cm2 were marked on the skin. Fluorescein-stained PRP was injected intradermally with 3 different gauge needles at 3 different doses (0.01, 0.03, and 0.05 mL). After injections, spreads of the fluorescent dye-covered areas in horizontal and vertical planes were measured and compared. For the horizontal plane measurements, the dye spread was measured first from the surface of the skin and second from the dermal surface of the skin. In addition, the width and depth of the dye spread in the dermis were measured from vertical sections. Changing the needle diameter does not affect the width or depth (thickness) of the PRP spread in the dermis. Increasing the applied dose to 0.03 mL increases the spread to the width and depth (thickness). In research evaluating the effectiveness of PRP treatments, it is necessary to report the volume of PRP to be applied per unit of tissue.

Systematic Review-The Potential Implications of Different Platelet-Rich Plasma (PRP) Concentrations in Regenerative Medicine for Tissue Repair.

The number of studies evaluating platelet-rich plasma (PRP) concentration has substantially grown in the last fifteen years. A systematic review on this field has been realized by evaluating in the identified studies the in vitro PRP concentration—also analyzing the platelet amount—and the in vivo PRP effects in tissue regeneration compared to any control. The protocol has been developed in agreement with the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses-Protocols (PRISMA-P) guidelines. Multistep research of the PubMed, MEDLINE, Embase, PreMEDLINE, Ebase, CINAHL, PsycINFO, Clinicaltrials.gov, Scopus database and Cochrane databases has permitted to identify articles on different concentrations of PRP in vitro and related in vivo impact for tissue repair. Of the 965 articles initially identified, 30 articles focusing on PRP concentration have been selected and, consequently, only 15 articles have been analyzed. In total, 40% (n = 6) of the studies were related to the fixed PRP Concentration Group used a fixed PRP concentration and altered the platelet concentration by adding the different volumes of the PRP (lysate) to the culture. This technique led to a substantial decrease in nutrition available at higher concentrations. Sixty percent (n = 9) of the studies were related to the fixed PRP Volume Group that used a fixed PRP-to-media ratio (Vol/Vol) throughout the experiment and altered the concentration within the PRP volume. For both groups, when the volume of medium (nutrition) decreases, a lower rate of cell proliferation is observed. A PRP concentration of 1.0 × 106 plt/μL, appears to be optimal thanks to the constant and plentiful capillary nutrition supply and rapid diffusion of growth factors that happen in vivo and it also respects the blood decree-law. The PRP/media ratio should provide a sufficient nutrition supply to prevent cellular starvation, that is, PRP ≤ 10% (Vol/Vol) and thus best mimic the conditions in vivo.

Platelet-Rich Plasma and its Use for Cicatricial and Non-Cicatricial Alopecias: A Narrative Review.

The concept and description of platelet-rich plasma (PRP) started in the field of hematology and is being extensively used in other fields of medicine. Interest in the application of PRP has been increasing in dermatology, such as in tissue regeneration, wound healing, scar revision, skin-rejuvenating effects, and alopecia. PRP is an autologous blood product containing high concentrations of platelets in a small volume of plasma. Different preparations of PRP may lead to different volumes of PRP, platelet concentration, and presence or absence of leukocytes. PRP is being used as a new therapy for some types of non-cicatricial alopecia such as androgenetic alopecia (AGA) and alopecia areata (AA) and, recently, new insights refer to the possibility of action in the field of cicatricial alopecia, like lichen planopillaris (LPP) and frontal fibrosing alopecia (FFA). This article aims to identify the major indications for the application of PRP in the field of hair disorders, including non-cicatricial and cicatricial alopecia.

Platelet and Leukocyte Concentration in Equine Autologous Conditioned Plasma Are Inversely Distributed by Layer and Are Not Affected by Centrifugation Rate

Background: Platelet rich plasma (PRP) is used extensively in equine regenerative medicine. Differences in preparation protocols give rise to significant variability in the cellular composition of PRP making it very difficult to establish a standard of care in the field. This study aimed to optimize the preparation protocol for leukocyte-reduced PRP (P-PRP).Methods: Blood (100 mL) was collected from horses (n = 5) and divided into 2 purple top EDTA tubes and 6 (15 mL) double syringesa with a final concentration of 10% acid citrate dextrose anticoagulant. Six double syringesa were collected from each horse; PRP samples were prepared in duplicate and centrifuged at 1,100 rpm (188 × g), 1,300 rpm (263 × g), or 1,500 rpm (350 × g). Duplicates were subjected to +/– braking at the end of centrifugation. The total volume of PRP generated was measured and divided into thirds. Each third (top, middle, and bottom) were drawn off separately using the inner (6 mL syringe) and placed in purple top EDTA tubes. Automated complete blood counts were performed on all peripheral whole blood and PRP samples.Results: The concentration of leukocytes was higher in the bottom layer of PRP compared to the top and middle layers (p < 0.0001). The concentration of platelets was slightly lower in the bottom layer of PRP than the middle layer (p = 0.02). Centrifugation braking increased the leukocyte concentration in the top (p = 0.03) and middle layers of PRP (p = 0.001). Centrifugation rate had no effect on the cellular composition of PRP (p = 0.1–0.6).Conclusions: Because layer of plasma affected both platelet and leukocyte concentrations in PRP, the most important modification for the current single spin, double syringe, plasma based PRP preparation protocols is to exclude the bottom 1/3 layer of PRP.

432 Patient and device generated variability in platelet-derived growth factors during platelet-rich plasma therapy for hair loss

Platelets contain α-granules that are reservoirs of critical growth factors (GFs) regulating cellular proliferation, migration, differentiation and angiogenesis. Platelet-rich plasma (PRP) can be effective in treating hair loss disorders as reported from several clinical trials, however the response within a study and between studies has been inconsistent. It is possible that this is related to quantitative and qualitative differences in platelet-derived GFs in PRP. It is currently unclear whether these differences result from inherent patient-to-patient variability or from the devices used to prepare PRP or both. To test these variables, we first compared platelet expression and release of prominent GFs (TGFβ1, PDGF-A, PDGF-BB, VEGF, FGF2 and EGF) between patient volunteers undergoing PRP therapy for hair loss. PRP was prepared using an FDA-cleared device which utilizes a density-based separation technique on a patented separator gel. Platelet GF expression and their levels in PRP were highly variable between patients (n=34) and failed the Shapiro-Wilk test for normality, suggesting an inherent patient-to-patient variability. The variability was more pronounced for VEGF and EGF while it was least for TGFβ1. We then compared GF levels in PRP to those prepared using another FDA-cleared device (n=7) which utilizes a dual spin protocol wherein the first soft spin removes the red blood cells while the second spin concentrates the platelets. A final PRP volume of 7-10 ml was produced in both devices although the original volume of blood used and platelet enrichment in PRP was different between them. Significant individual differences in GF levels were also detected when PRP prepared from both devices was compared. Thus, our study suggests that quantitative and qualitative differences in GFs are not only inherent between patients but may also be driven by the devices used to prepare PRP. This may affect the clinical data reported in the literature contributing to inconsistent clinical responses.

Experience of local using of platelet-rich plasma in 25 patients with diabetic foot

The aim of the study was to evaluate the effectiveness of local using of autologous platelet-rich plasma in the treatment of patients with diabetic foot in stage 2. The study included 25 patients with a diagnosis of diabetic foot in stage 2. At the time of inclusion in the study, all patients had a defect of 3–7 cm2 of the skin and subcutaneous adipose tissue in the plantar part of the foot. In addition to the standard treatment, it was decided to perform the local administration of autologous platelet-rich plasma in all patients. The entire platelet-rich plasma volume obtained was injected in the edge of skin around the wound using 30-gauge needles. Repeated injections were performed every 5–7 days until complete healing of the soft tissue defect. To evaluate the effectiveness of the treatment, the area of the ulcerative defect was measured before the manipulation, as well as at an interval of 14 days until the ulcer was completely healed. The following results are obtained: prior to the manipulation, the area of ulcerative defects in the examined population was 511.9±120.3 mm2. On the 14th day, this indicator was already 353.6±112.5 mm2 and was significantly different from the area of the ulcerative defects before manipulation (p&lt;0.01). On the 28th day, complete healing of diabetic ulcers was observed in 11 (44%) patients, and the area of the skin defect in the study population was 22.4±24.3 mm2 and was significantly different from those in all previous study dates (p&lt;0.01). On day 42, we noted the complete healing of ulcers in absolutely all patients. Thus, local injection of an autologous platelet-rich plasma improves the local regenerative process and leads to complete healing of stage 2 diabetic ulcers with an area of 3–7 cm2 for 6 weeks.

Treatment of Muscle Injuries with Platelet-Rich Plasma: a Review of the Literature

This review discusses the current literature regarding the use of platelet-rich plasma (PRP) in the treatment of muscle strain injuries. Case series as well as experimental trials for both human and animal models are covered. Multiple studies have examined outcomes for the use of PRP in the treatment of muscle strain injuries. PRP has been shown to promote muscle recovery via anabolic growth factors released from activated platelets, and in doing so, potentially reduces pain, swelling, and time for return to play. In vitro studies support the regenerative potential of PRP for acute soft tissue injuries. Multiple clinical case series for PRP injections in the setting of muscle strains demonstrate imaging evidence for faster healing, less swelling, which can decrease time for return to play. These studies, however, are retrospective in nature, and few randomized controlled studies exist to demonstrate a clear clinical benefit. Additionally, there is tremendous heterogeneity regarding the injectant preparation, optimum platelet concentration, presence of leukocytes, and volume of PRP which should be administered as well as number of and timing of treatments.

Erythrocyte sedimentation rate and fibrinogen concentration of whole blood influences the cellular composition of platelet-rich plasma obtained from centrifugation methods

Erythrocyte sedimentation rate (ESR), which reflects the sedimentation rate of platelets, leukocytes and erythrocytes in response to centrifugal force, may influence the cellular composition of platelet-rich plasma (PRP) obtained via centrifugation methods. However, no relevant studies have substantiated this. In the present study, blood was collected from 40 healthy volunteers and used to prepare PRP with two plasma-based preparation systems [YinPRP and Plasma Rich in Growth Factor (PRGF) systems] and two buffy coat-based systems (RegenPRP and WEGOPRP systems) in a single-donor model. Volumes of PRP and platelet-poor plasma (PPP) that were removed in the preparation process were recorded. Analyses of ESR, haematocrit, C-reaction protein, coagulation, serum glucose and serum lipid of the whole blood used for PRP preparation were performed to evaluate the levels of ESR and the factors known to influence it. Whole blood analysis was performed to evaluate the cellular composition of PRP. Results demonstrated that there were marked positive correlations between the ESR of the whole blood used for PRP preparation and PPP removal efficiencies, platelet concentrations, platelet capture efficiencies and platelet enrichment factors of PRP formulations obtained from plasma-based systems, and PRP yield efficiency of RegenPRP and PPP removal efficiency of WEGOPRP. Furthermore, there were marked negative correlations between ESR and concentrations and enrichment factors of platelets, leukocytes and erythrocytes of RegenPRP. Fibrinogen concentration of the whole blood, which had a marked positive correlation with ESR, also influenced the cellular composition of PRP. These findings may increase the understanding of PRP preparation and provide substantial evidence for the individualised optimisation of PRP preparation systems used in clinical practice.

Necessity of standardized protocol for platelet-rich plasma therapy in temporomandibular joint osteoarthritis.

Temporomandibular joint (TMJ) osteoarthritis (OA) is defined as chronic joint pain caused by the progressive degeneration of the articular cartilage through an imbalance between anabolic and catabolic conditions in the TMJ1. Although the pathophysiological etiologies of TMJ-OA are largely unknown, the excessive mechanical stress, aging processes involved with hormonal alterations, and individual heredity have been verified as risk factors for TMJ-OA. On the other hand, the increased risk factors induce a homeostatic imbalance between the anabolic (synthesis) and catabolic (degeneration) conditions in the articular cartilage of the TMJ. Subsequently, a homeostatic imbalance induces an upregulation of the pro-inflammatory cytokines, such as interleukin (IL)-1β, tumor necrosis factor-α, and IL-6 and catabolic growth factors in the synovial fluids of the TMJ2. Finally, upregulated pro-inflammatory cytokines and catabolic growth factors not only induce an increase in the cartilage degrading enzymes, such as matrix metalloproteinase (MMP)-13, MMP-3, MMP-1, a disintegrin, and metalloproteinase with thrombospondin motifs (ADAMTS)-4, and ADAMTS-5 to progressively breakdown of extracellular matrix3, but also induce the abnormal remodeling of the subchondral bone and the apoptosis of chondrocytes in the articular cartilage of TMJ. In addition, the biological linkage between the progressive degeneration of the articular cartilage of the TMJ and the occurrence of orofacial pain is still largely unknown. For these reasons, clinical treatments for patients with TMJ-OA focused only on the relief from orofacial pain caused by progressive degeneration of the articular cartilage. Therefore, as a strategy for maintaining the homeostasis of the synovial joints, recent studies on preventive medicine for OA attempted to shift the metabolic status of the joints from the catabolic to the anabolic state using anabolic materials. Platelet-rich plasma (PRP) is blood plasma that has been enriched with platelets and contains several different growth factors and cytokines that can stimulate the healing of various tissues. Therefore, autologous PRP has been considered a clinical anabolic material for patients with chronic joint pain caused by progressive cartilage degeneration of the synovial joints. A systematic review and meta-analysis related to the clinical efficacy of intra-articular PRP injection into the synovial joints with OA have shown significant clinical improvements4. More recently, Kutuk et al.5 and Hegab et al.6 reported that an intra-articular PRP injection is an effective treatment for TMJ-OA through the regeneration of fibrocartilage and cartilage, bone repair in the TMJ. On the other hand, Bottegoni et al.7 recently reported that the intra-articular PRP injection into the knee joint with moderate OA showed a decreased potential in elderly patients aged 80 years or over. This report indicates that the intra-articular PRP injection for patients with TMJ-OA can be performed in accordance with the physiological conditions and clinical diseases of patients. Because autologous PRP is prepared from the patient's own blood, the concentrated components of PRP differ according to the physiological conditions and clinical diseases of patients. For example, if PRP is prepared from a patient with autoimmune diseases, such as rheumatoid arthritis, it may have highly concentrated pro-inflammatory cytokines to accelerate the progressive cartilage degeneration of the TMJ. Therefore, it is important to standardize the clinical PRP preparation protocol for patients with TMJ-OA. Furthermore, standardized methods may include the number of platelets, timing and volume of PRP for injection according to the physiological conditions and clinical diseases of patients.

A Call for a Standard Classification System for Future Biologic Research: The Rationale for New PRP Nomenclature

Autologous cell therapies including platelet-rich plasma (PRP) and bone marrow concentrate (BMC) are increasingly popular options for soft tissue and joint-related diseases. Despite increased clinical application, conflicting research has been published regarding the efficacy of PRP, and few clinical publications pertaining to BMC are available. Preparations of PRP (and BMC) can vary in many areas, including platelet concentration, number of white blood cells, presence or absence of red blood cells, and activation status of the preparation. The potential effect of PRP characteristics on PRP efficacy is often not well understood by the treating clinician, and PRP characteristics, as well as the volume of PRP delivered, are unfortunately not included in the methods of many published research articles. It is essential to establish a standard reporting system for PRP that facilitates communication and the interpretation and synthesis of scientific investigations. Herein, the authors propose a new PRP classification system reflecting important PRP characteristics based on contemporary literature and recommend adoption of minimal standards for PRP reporting in scientific investigations. Widespread adoption of these recommendations will facilitate interpretation and comparison of clinical studies and promote scientifically based progress in the field of regenerative medicine.

Platelet-Rich Plasma: Is It Ready for Prime Time?

Platelet-rich plasma (PRP) has been used clinically for its potentially enhanced soft-tissue healing properties. These healing properties, which stem from its derivation from autologous blood, have been attributed to the increased concentrations of growth factors and secretory proteins. PRP thereby hopefully enhances the recruitment, proliferation, and differentiation of cells involved in tissue regeneration1,2. The majority of orthopaedic applications for PRP can be classified into four groups: chronic tendinopathies, acute ligamentous injuries, muscle injuries, and intraoperative augmentation2. As noted by Hall et al.1, several PRP preparation systems are commercially available. The volume of autologous blood, centrifugation rate and time, delivery method, activating agent, leukocyte concentration, final PRP volume, and final platelet and growth factor concentrations vary among these systems. Hematologic variations between patients (e.g., leukocyte count and platelet count) may also affect the final PRP preparation. Debate continues regarding the optimal quantity of platelets and growth factors required for muscle and tendon-healing1. In this study, the authors …

Tissue Regeneration in Loss of Substance on the Lower Limbs through Use of Platelet-Rich Plasma, Stem Cells from Adipose Tissue, and Hyaluronic Acid

Platelet-rich plasma (PRP) induces wound regeneration and tissue repair through cell proliferation and differentiation, promoting tissue healing and also acting as an autologous scaffold. With a small quantity of blood, it is possible to obtain the necessary optimal volume of PRP to treat the loss of substance in the lower limb. It has been demonstrated that mesenchymal stem cells are present in the adipose tissue (thus accelerating the effect of the PRP). The analysis involved 30 patients with lesions ranging from ulcerative, dystrophic, with substance loss, with differentiating etiopathogenesis all localized on the inferior limb, and to those treated with PRP and autologous fat grafts. The wounds were covered with a 3-dimensional, polymerized hyaluronic acid medicated biologic dressing. The authors' protocol consists of a general checkup; wound examination; instrumental, microbiological, and immunohistochemical diagnostic examinations; and acquisition of photographic images with follow-up at 0, 1, 2, and 3 weeks; 1, 3, and 6 months; and 1 year. The results show an improvement from minor to moderate in 100% of patients after 3 weeks, healing in less than 6 weeks in 47% of patients, and complete wound healing in 57% of patients within 3 months. The authors' data demonstrate the ability of the combination of PRP and autologous adipose graft to regenerate tissue and epithelialization with wound closure, with a significant healing-time reduction. Furthermore, the minimally invasive technique is well accepted by patients, with a noteworthy improvement of the quality of life along with cost reduction due to the fewer number of medications.

Étude comparative de cinq techniques de préparation plaquettaire ( platelet-rich plasma)

Aim of the study Injections of platelet-rich plasma (PRP) constitute a new therapeutic for treating chronic tendinopathies. The injection being carried out in the tendon, the volume of PRP should thus be minimal (to decrease the intratendinous pressure and to minimize pain). This PRP should also have a raised platelet count. The quantity of released growth factors could be related to the system of preparation employed. We thus carried out a comparative study of five techniques of preparation of PRP described in the literature. Materials and methods Samples of venous blood were taken among five patients in order to compare five techniques of preparation of PRP: University Hospital of Liège technique, Curasan ® PRP Kit, Plateltex ®, GPS ®II and RegenLab ®. Results The various techniques make it possible to obtain more important platelet concentration than in blood, with variable volumes (0,3 to 6 ml). The number of platelets per microlitre appears higher with Plateltex ® and obtains smallest volume of PRP. The other techniques also give small volumes except for the GPS ®II. The number of collected platelets with this technique appears thus higher. The best collect efficiency is obtained with RegenLab ®. Conclusion The technique Plateltex ® makes it possible to collect the highest concentration of platelets in the smallest volume available.

Efficacy of Platelet‐Rich Plasma on Wound Healing in Rabbits

The purpose of this study was to evaluate if the healing of full-thickness skin wounds was accelerated by platelet-rich plasma (PRP). Four 2.5 x 2.5-cm full-thickness skin wounds were created on the backs of 15 New Zealand white rabbits. One wound on each animal received 0.3, 0.6, or 0.9 ml PRP, and the fourth wound served as a control. Seven and eight animals were sacrificed after 1 or 2 weeks, respectively, to determine histomorphometrically the epithelialization rate, contraction rate, healing rate, tissue fill, and volume fractions of fibroblasts, neutrophils, macrophages, and blood vessels. Only the 0.6- and 0.9-ml groups had significantly lower contraction rates than the controls after 2 weeks (P <0.05). Although no statistically significant differences were found in other parameters between the PRP-treated wounds and the controls, the PRP treatment led to increases in average epithelialization rates and volume fraction of blood vessels at both time periods. The PRP also seemed to have the most positive effect on healing rate, tissue fill, and volume fraction of fibroblasts during week 1 compared to week 2. The PRP treatment enhanced healing in full-thickness wounds by reducing the contraction rate with a trend toward acceleration of the epithelial migration and the angiogenic response. Further studies with larger sample sizes should be conducted to improve statistical sensitivity. Longer time intervals and modifications of PRP volume should also be explored to evaluate the long-term efficacy of PRP on wound healing.

Autologous Platelet Gel: An In Vitro Analysis of Platelet-Rich Plasma Using Multiple Cycles

Autologous platelet gel (APG) has become an expanding field for perfusionists. By mixing platelet-rich plasma (PRP) with thrombin and calcium, platelet gel is prepared and used in many surgical settings. There are many devices used to produce PRP. This study evaluates the Medtronic Magellan Autologous Platelet Separator. The purpose of this study was to show that processing two cycles of the same syringe could reduce the amount of blood required to produce a specific volume of PRP. Three 60-mL syringes of whole blood with anticoagulant were removed from 15 elective coronary artery bypass patients. Each syringe produced 9 mL of PRP and 1 mL was sent to the laboratory for analysis. The remaining whole blood in each syringe was processed a second time with a yield of 5 mL of PRP with 1 mL sent to the laboratory. With this data, the Magellan was assessed in three phases. The first phase focused on the consistency of the Magellan. Laboratory values of hematocrit, platelet count, white blood cell count, and fibrinogen were compared between each syringe processed by the device. The second phase dealt with the percentage of platelets in the PRP that the Magellan was able to capture. Finally, results of both cycles were combined and compared against baseline values. Most of the hematological factors evaluated between each syringe were consistent in both cycles. The Magellan was able to capture nearly 70% of all platelets in the PRP of the first cycle and 18.5% in the second cycle. By mathematically combining both cycles, platelet counts averaged 2.8 times baseline with a 3.3 times baseline increase when the volume of the two cycles was weighted. This weighted average was done to reflect a higher concentration of Cycle 1 platelets than Cycle 2 in each sample. This study proved that processing each syringe of whole blood twice could reduce blood requirements while maintaining an effective platelet yield and volume. It also showed that the Magellan does conform to benchmark testing done at Medtronic.