Autologous platelet-rich plasma: a biological supplement to enhance adipose-derived mesenchymal stem cell expansion

Comparison of corneal epitheliotrophic capacities among human platelet lysates and other blood derivatives

PURPOSE

To evaluate the corneal epitheliotropic abilities of two commercialized human platelet lysates (HPLs) and to compare the results with other blood derivatives, including human peripheral serum (HPS) and bovine fetal serum (FBS).

METHODS

In vitro, human corneal epithelial cells were incubated in various concentrations (0%, 3%, 5% and 10%) of blood derivatives. Two commercialized HPLs, including UltraGRO TM (Helios, Atlanta, GA) and PLTMax (Mill Creek, Rochester, MI), were tested and compared with HPS and FBS. Scratch-induced directional wounding assay was performed to evaluate cellular migration. MTS assay was used to evaluate cellular proliferation. Cellular differentiation was examined by scanning electron microscopy, inverted microscopy and transepithelial electrical resistance. Sprague-Dawley rats were used to evaluate the effects of the blood derivatives on corneal epithelial wound healing in vivo. Different blood derivatives were applied topically every 2 hours for 2 days after corneal epithelial debridement. The concentrations of epidermal growth factor (EGF), transforming growth factor -β1 (TGF-β1), fibronectin, platelet-derived growth factor-AB (PDGF-AB), PDGF-BB, and hyaluronic acid in different blood derivatives were evaluated by enzyme-linked immunosorbent assay (ELISA).

RESULTS

In vitro experiments demonstrated statistically comparable epitheliotropic characteristics in cellular proliferation, migration, and differentiation for the two commercialized HPLs compared to FBS and HPS. Cells cultured without any serum were used as control group. The epitheliotropic capacities were statistically higher in the two commercialized HPLs compared to the control group (p<0.05). Among the different concentrations of blood derivatives, the preparations with 3% yielded better outcomes compared to 5% and 10%. In rats, HPLs also caused improved but not statistically significant wound healing compared to HPS. All the blood derivatives had better wound healing ratios than the control group (p<0.05). In the quantification of epitheliotropic factors, UltraGRO and PLTMax had significantly higher levels of EGF, TGF- β1, fibronectin than human peripheral serum (p<0.05).

CONCLUSIONS

Both commercialized HPLs showed comparable corneal epitheliotropic abilities and wound healing rates compared to HPS and FBS in the in vivo and in vitro studies. Our results suggest that HPLs may have the potential to replace HPS in the treatment of corneal epithelial problems.

A consensus introduction to serum replacements and serum-free media for cellular therapies

The cell therapy industry is a fast-growing industry targeted toward a myriad of clinical indications. As the cell therapy industry matures and clinical trials hit their pivotal Phase 3 studies, there will be a significant need for scale-up, process validation, and critical raw material quality assurance. Part of the well discussed challenges of upscaling manufacturing processes there is a less discussed issue relating to the availability of raw materials in the needed quality and quantities. The FDA recently noted that over 80% of the 66 investigational new drug (IND) applications for mesenchymal stem cell (MSC) products analyzed described the use of FBS during manufacturing. Accumulated data from the past years show an acceleration in serum consumption by at least 10%-15% annually, which suggests that the global demand for serum may soon exceed the supply. Ongoing concerns of safety issues due to risks of various pathogen contaminations, as well as issues related to the aforementioned serum variability that can affect final product reproducibility, are strong motivators to search for serum substitutes or serum-free media. it is important to note that there are no accepted definitions for most of these terms which leads to misleading's and misunderstandings, where the same term might be defined differently by different vendors, manufacturer, and users. It is the drug developer's responsibility to clarify what the supplied labels mean and to identify the correct questions and audits to ensure quality. The paper reviews the available serum replacements, main components, basic strategies for replacement of serum and suggests definitions.

The Use of Adipose-Derived Progenitor Cells and Platelet-Rich Plasma Combination for the Treatment of Supraspinatus Tendinopathy in 55 Dogs: A Retrospective Study

OBJECTIVE

To report clinical findings and outcomes for 55 dogs with supraspinatus tendinopathy (ST) treated with adipose-derived progenitor cells and platelet-rich plasma (ADPC-PRP) therapy.

METHODS

Medical records of client-owned dogs diagnosed with ST that were treated with ADPC-PRP combination therapy were reviewed from 2006 to 2013. Data collected included signalment, medical history, limb involvement, prior treatments, physical and orthopedic examination, objective temporospatial gait analysis findings, diagnostic imaging results (radiography, magnetic resonance imaging, musculoskeletal ultrasonography), arthroscopy findings, and outcome.

RESULTS

Following ultrasound-guided injection of ADPC-PRP, objective gait analysis was available on 25 of the 55 dogs at 90 days post ADPC-PRP therapy. Following treatment, a significant increase in total pressure index percentage (TPI%) was noted in the injured (treated) forelimb at 90 days post treatment (p = 0.036). At 90 days following treatment, 88% of cases had no significant difference in TPI% of the injured limb to the contralateral limb. The remaining 12% of cases had significantly improved (p = 0.036). Bilateral shoulder diagnostic musculoskeletal ultrasound revealed a significant reduction in tendon size (CSA) in the treated tendon at 90 days following treatment when compared to the initial CSA (p = 0.005). All cases showed significant improvement in fiber pattern of the affected supraspinatus tendon by the ultrasound shoulder pathology rating scale.

CLINICAL RELEVANCE

These findings suggest that ADPC-PRP therapy should be considered for dogs with ST.

Adhesive Capsulitis in Eight Dogs: Diagnosis and Management

OBJECTIVE

To describe clinical and diagnostic findings as well as management of adhesive capsulitis in dogs.

BACKGROUND

Adhesive capsulitis, also known as frozen shoulder, is a syndrome defined by loss of range of motion of the shoulder and may be the end-stage manifestation of several primary conditions.

EVIDENTIARY VALUE

This is a case series report of eight dogs with chronic forelimb lameness diagnosed with adhesive capsulitis.

METHODS

Medical records (June 1, 2010-September 1, 2015) including, physical examination findings, radiographic findings, magnetic resonance imaging (MRI) findings, arthroscopy findings, and treatment plans were reviewed.

RESULTS

All dogs presented with a chronic, grade III-VI/VI forelimb lameness. On orthopedic examination, all dogs had moderate to significant discomfort on shoulder extension and flexion and severe restriction of range of motion. Six of the eight dogs had evidence of bone remodeling and sclerosis in the affected shoulder on radiographs. Six of the dogs had an initial diagnostic ultrasound performed, which revealed evidence of fibrous scar tissue. Five dogs had MRI performed that revealed moderate shoulder effusion and enhancement of the synovial lining of the shoulder. Arthroscopy was performed in five of the eight patients. Three were noted to have significant contracture, adhesions, and fibrous scar tissue of the joint capsule. Severe inflammation was noted throughout the synovium of two patients. All eight patients tried conservative management consisting of oral medications and rehabilitation therapy. Five of the eight patients received extracorporeal shockwave therapy. Three patients received regenerative medicine treatment in the affected supraspinatus and shoulder. Regardless of the treatment elected, none of the dogs were reported to have significant improvement.

CONCLUSION

Adhesive capsulitis is an uncommon cause of chronic forelimb lameness. Further investigation is needed to describe the etiology and pathogenesis of adhesive capsulitis in dogs to evaluate the effectiveness of both non-surgical and surgical treatment modalities, establish treatment protocols, and evaluate short- and long-term clinical outcome of patients.

APPLICATION

Adhesive capsulitis should be considered in patients with chronic forelimb lameness and moderate to significant discomfort and restriction on shoulder range of motion.

Combined use of platelet rich plasma & micro-fat in sport and race horses with degenerative joint disease: preliminary clinical study in eight horses

BACKGROUND

To assess the safety and potential efficacy of a standardized technique consisting of intra-articular injection of 10 cc of a homogeneous mixed product using autologous micro-fat and platelet rich plasma (PRP) (ratio 1:1) in the carpus or the fetlock joint of sport horses presenting degenerative joint disease (DJD).

METHODS

Eight sport horses with DJD confirmed by radiography and ultrasonography and causing lameness and the impossibility to compete were treated. PRP was prepared after a double centrifugation whereas micro-fat was harvested and purified using a closed system. The two products were connected and mixed by gentle back and forth shaking of the syringes to finally obtain 10 ml of an homogeneous mixed product. Follow up was performed from 5 to 10 months with assessment of AAEP lameness score and return to training and competition.

RESULTS

Nine joints were treated with significant improvement of the AAEP lameness score three months after the procedure (p = 0.021). Four horses returned to official competition between 5 to 10 months after the procedure (7.0±2.5) and three of them resumed intensive training between 5 to 9 months (6.3±2.3). No adverse event occurred.

CONCLUSION

This study is a first step in the development of innovative therapy for DJD which combines the potential chondrogenic differentiation of MSCs inside equine adipose tissue with the proliferative effect of growth factors present in PRP.

Adipose-Derived Stem Cells for Tissue Engineering and Regenerative Medicine Applications

Adipose-derived stem cells (ASCs) are a mesenchymal stem cell source with properties of self-renewal and multipotential differentiation. Compared to bone marrow-derived stem cells (BMSCs), ASCs can be derived from more sources and are harvested more easily. Three-dimensional (3D) tissue engineering scaffolds are better able to mimic the in vivo cellular microenvironment, which benefits the localization, attachment, proliferation, and differentiation of ASCs. Therefore, tissue-engineered ASCs are recognized as an attractive substitute for tissue and organ transplantation. In this paper, we review the characteristics of ASCs, as well as the biomaterials and tissue engineering methods used to proliferate and differentiate ASCs in a 3D environment. Clinical applications of tissue-engineered ASCs are also discussed to reveal the potential and feasibility of using tissue-engineered ASCs in regenerative medicine.

Comparative Analysis of Media and Supplements on Initiation and Expansion of Adipose-Derived Stem Cells

Adipose-derived stem cells (ASCs) are being tested in clinical trials related to cell-based regenerative therapies. Although most of the current expansion protocols for ASCs use fetal calf serum (FCS), xenogeneic-free medium supplements are greatly desired. This study aims to compare the effect of FCS, human platelet lysate (hPL), and a fully defined medium on the initiation and maintenance of ASC cultures. ASCs obtained from five donors were cultured in five different media: StemPro, Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% hPL, or α-minimum essential medium (A-MEM) supplemented with 5% hPL, 10% hPL, or 10% FCS. The effect of media on proliferation, colony-forming units (CFUs), attachment, and morphology was assessed along with cell size, granularity, and immunophenotype. StemPro greatly compromised the initiation of ASC cultures, which could not survive more than a few passages. Cells cultured in A-MEM proliferated at a faster rate than in DMEM, and hPL significantly enhanced cell size, granularity, and proliferation compared with FCS. All media except StemPro supported CFUs equally well. Analysis of surface markers revealed higher levels of CD73 and CD105 in FCS-cultured ASCs, whereas increased levels of CD146 were found in hPL-cultured cells. Multiparametric flow cytometric analysis performed after seven passages revealed the existence of four distinct ASC subpopulations, all positive for CD73, CD90, and CD105, which mainly differed by their expression of CD146 and CD271. Analysis of the different subpopulations might represent an important biological measure when assessing different medium formulations for a particular clinical application.

Adipose tissue-derived mesenchymal stem cells and platelet-rich plasma: stem cell transplantation methods that enhance stemness

Because of their ease of isolation and relative abundance, adipose-derived mesenchymal stem cells (ASCs) are a particularly attractive autologous cell source for various therapeutic purposes. ASCs retain a high proliferation capacity in vitro and have the ability to undergo extensive differentiation into multiple cell lineages. Moreover, ASCs secrete a wide range of growth factors that can stimulate tissue regeneration. Therefore, the clinical use of ASCs is feasible. However, the potential of ASCs differs depending on the donor's medical condition, including diseases such as diabetes. Recent studies demonstrated that ASCs from diabetic donors exhibit reduced proliferative potential and a smaller proportion of stem cell marker-positive cells. Therefore, to ensure the success of regenerative medicine, tissue engineering methods must be improved by the incorporation of factors that increase the proliferation and differentiation of stem/progenitor cells when autologous cells are used. Platelet-rich plasma (PRP), which contains high levels of diverse growth factors that can stimulate stem cell proliferation and cell differentiation in the context of tissue regeneration, has recently been identified as a biological material that could be applied to tissue regeneration. Thus, co-transplantation of ASCs and PRP represents a promising novel approach for cell therapy in regenerative medicine. In this review, we describe the potential benefits of adding PRP to ASCs and preclinical and clinical studies of this approach in various medical fields. We also discuss the mechanisms of PRP action and future cell-based therapies using co-transplantation of ASCs and PRP.

Human platelet lysate: Replacing fetal bovine serum as a gold standard for human cell propagation?

The essential physiological role of platelets in wound healing and tissue repair builds the rationale for the use of human platelet derivatives in regenerative medicine. Abundant growth factors and cytokines stored in platelet granules can be naturally released by thrombin activation and clotting or artificially by freeze/thaw-mediated platelet lysis, sonication or chemical treatment. Human platelet lysate prepared by the various release strategies has been established as a suitable alternative to fetal bovine serum as culture medium supplement, enabling efficient propagation of human cells under animal serum-free conditions for a multiplicity of applications in advanced somatic cell therapy and tissue engineering. The rapidly increasing number of studies using platelet derived products for inducing human cell proliferation and differentiation has also uncovered a considerable variability of human platelet lysate preparations which limits comparability of results. The main variations discussed herein encompass aspects of donor selection, preparation of the starting material, the possibility for pooling in plasma or additive solution, the implementation of pathogen inactivation and consideration of ABO blood groups, all of which can influence applicability. This review outlines the current knowledge about human platelet lysate as a powerful additive for human cell propagation and highlights its role as a prevailing supplement for human cell culture capable to replace animal serum in a growing spectrum of applications.

Comparative epigenetic influence of autologous versus fetal bovine serum on mesenchymal stem cells through in vitro osteogenic and adipogenic differentiation

Mesenchymal stem cells (MSCs) derived from bone marrow (BM) represents a useful source of adult stem cells for cell therapy and tissue engineering. MSCs are present at a low frequency in the BM; therefore expansion is necessary before performing clinical studies. Fetal bovine serum (FBS) as a nutritional supplement for in vitro culture of MSCs is a suitable additive for human cell culture, but not regarding subsequent use of these cells for clinical treatment of human patients due to the risk of viral and prion transmission as well as xenogeneic immune responses after transplantation. Recently, autologous serum (AS) has been as a supplement to replace FBS in culture medium. We compared the effect of FBS versus AS on the histone modification pattern of MSCs through in vitro osteogenesis and adipogenesis. Differentiation of stem cells under various serum conditions to a committed state involves global changes in epigenetic patterns that are critically determined by chromatin modifications. Chromatin immunoprecipitation (ChIP) coupled with real-time PCR showed significant changes in the acetylation and methylation patterns in lysine 9 (Lys9) of histone H3 on the regulatory regions of stemness (Nanog, Sox2, Rex1), osteogenic (Runx2, Oc, Sp7) and adipogenic (Ppar-γ, Lpl, adiponectin) marker genes in undifferentiated MSCs, FBS and AS. All epigenetic changes occurred in a serum dependent manner which resulted in higher expression level of stemness genes in undifferentiated MSCs compared to differentiated MSCs and increased expression levels of osteogenic genes in AS compared to FBS. Adipogenic genes showed greater expression in FBS compared to AS. These findings have demonstrated the epigenetic influence of serum culture conditions on differentiation potential of MSCs, which suggest that AS is possibly more efficient serum for osteogenic differentiation of MSCs in cell therapy purposes.

Platelet Preparations for Use in Facial Rejuvenation and Wound Healing: A Critical Review of Current Literature

In facial plastic surgery, the potential for direct delivery of growth factors from platelet preparations has been of particular interest for use in facial rejuvenation, recovery after facial surgery, and wound healing. A literature search was conducted through PubMed for the terms PRP, PRFM, platelet-rich plasma, platelet-rich fibrin matrix, platelet preparations, platelet therapy, growth factors, platelet facial, platelet facial rejuvenation, platelet wound healing, platelet plastic surgery. Articles pertaining to the use of platelet preparations in facial surgery and wound healing in plastic surgery after 2001 were included. Thirteen in vitro studies showed use of platelet-rich plasma (PRP) and platelet-rich fibrin matrix (PRFM) had a significant effect on cellular activity. Twenty-four out of 28 animal studies exhibited favorable results with use of a platelet preparation, including five of six studies that showed enhanced fat graft survival with addition of a platelet preparation. Twenty-three case series and clinical trials were identified, only two of which showed no differences. Twenty-one reported favorable results with use of various platelet preparations. A total of 47 studies used PRP, four studies evaluated Leukocyte-rich PRP, and fourteen studies used PRFM. The vast majority of studies examined show a significant and measurable effect on cellular changes, wound healing, and facial esthetic outcomes with use of platelet preparations, both topical and injectable. One must also consider possible publication bias against null results that may have had an influence on the data that were available for review. However, the preponderance of studies suggests that platelet preparations might represent an as-of-yet untapped adjunct in facial plastic surgery.