Mesenchymal stem cell injections improve symptoms of knee osteoarthritis

Intra-articular autologous uncultured adipose-derived stromal cell transplantation inhibited the progression of cartilage degeneration

The role of uncultured adipose-derived stromal cells for osteoarthritis treatment remains unclear despite sporadic reports supporting their use in clinical settings. This study aimed to evaluate the therapeutic effects of autologous uncultured adipose-derived stromal cell transplantation in a rabbit osteoarthritis model. Uncultured adipose-derived stromal cells isolated from rabbits were administered via intra-articular injection into the knees after osteoarthritis onset. Animals were sacrificed at 8 and 12 weeks after osteoarthritis onset to compare the macroscopic, histological, and immunohistochemical characteristics between the uncultured adipose-derived stromal cell and control groups. Co-culture assay was also performed. The chondrocytes isolated from the model were co-cultured with adipose-derived stromal cells. The cell viability of chondrocytes and expression of chondrocyte-specific genes in the co-culture (uncultured adipose-derived stromal cell) group were compared with the mono-culture (control; chondrocytes only) group. In macroscopic and histological analyses, the uncultured adipose-derived stromal cell group showed less damage to the cartilage surface than the control group at 8 and 12 weeks after osteoarthritis onset. In immunohistochemical and co-culture assay, the uncultured adipose-derived stromal cell group showed higher expression of collagen type II and SRY box-9 and lower expression of matrix metalloproteinase-13 than the control group. The cell viability of chondrocytes in the uncultured adipose-derived stromal cell group was higher than that in the control group. Intra-articular autologous uncultured adipose-derived stromal cell transplantation inhibited the progression of cartilage degeneration in a rabbit osteoarthritis model by regulating chondrocyte viability and secreting chondrocyte-protecting cytokines or growth factors, which promote anabolic factors and inhibit catabolic factors. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1376-1386, 2019.

Effect of Lidocaine on Viability and Gene Expression of Human Adipose-derived Mesenchymal Stem Cells: An in vitro Study

OBJECTIVE

To assess the biologic effects of lidocaine on the viability, proliferation, and function of human adipose tissue-derived mesenchymal stromal/stem cells (MSCs) in vitro.

METHODS

Adipose-derived MSCs from three donors were exposed to lidocaine at various dilutions (2 mg/mL to 8 mg/mL) and exposure times (0.5 to 4 hours). Cell number and viability, mitochondrial activity, and real-time reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR) were analyzed at 0 (immediate effects) or 24 and 48 hours (recovery effects) after treatment with lidocaine.

RESULTS

Trypan blue staining showed that increasing concentrations of lidocaine decreased the number of observable viable cells. 3-[4,5,dimethylthiazol-2-yl]-5-[3-carboxymethoxy-phenyl]-2-[4-sulfophenyl]-2H-tetrazolium (MTS) assays revealed a concentration- and time- dependent decline of mitochondrial activity and proliferative ability. Gene expression analysis by RT-qPCR revealed that adipose-derived MSCs exposed to lidocaine express robust levels of stress response/cytoprotective genes. However, higher concentrations of lidocaine caused a significant downregulation of these genes. No significant differences were observed in expression of extracellular matrix (ECM) markers COL1A1 and DCN except for COL3A1 (P < .05). Levels of messenger RNA (mRNA) for proliferation markers (CCNB2, HIST2H4A, P < .001) and MKI67 (P < .001) increased at 24 and 48 hours. Expression levels of several transcription factors- including SP1, PRRX1, and ATF1-were modulated in the same manner. MSC surface markers CD44 and CD105 demonstrated decreased expression immediately after treatment, but at 24 and 48 hours postexposure, the MSC markers showed no significant difference among groups.

CONCLUSION

Lidocaine is toxic to MSCs in a dose- and time- dependent manner. MSC exposure to high (4-8 mg/mL) concentrations of lidocaine for prolonged periods can affect their biologic functions. Although the exposure time in vivo is short, it is essential to choose safe concentrations when applying lidocaine along with MSCs to avoid compromising the viability and potency of the stem cell therapy.

Treatment of knee osteoarthritis with intra-articular injection of autologous adipose-derived mesenchymal progenitor cells: a prospective, randomized, double-blind, active-controlled, phase IIb clinical trial

Objective

Human adipose-derived mesenchymal progenitor cells (haMPCs) are stem cells with multiple differentiation potential and immunomodulatory function. Re-Join® comprises in vitro expanded haMPCs from adipose tissue of patients combined with cell suspension solution. This study was undertaken to evaluate the efficacy and safety of Re-Join® in patients with symptomatic knee osteoarthritis (OA).

Methods

Patients with Kellgren–Lawrence grade 1–3 knee OA were recruited from two centers and randomized to receive intra-articular injection of Re-Join® or HA. Pain and function were assessed by using WOMAC score, VAS, and SF-36. Magnetic resonance imaging (MRI) analysis was performed to measure cartilage repair. Adverse events (AEs) were collected.

Results

Fifty-three patients were randomized. Significant improvements in WOMAC, VAS, and SF-36 scores were observed in both groups at months 6 and 12 compared with baseline. Compared with the HA group, significantly more patients achieved 50% improvement of WOMAC and a trend of more patients achieved a 70% improvement rate in Re-Join® group after 12 months. Meanwhile, there was notably more increase in articular cartilage volume of both knees in the Re-Join® group than in the HA group after 12 months as measured by MRI. AEs were comparable between two groups. Most AEs were mild and moderate except one SAE of right knee joint infection in the HA group.

Conclusions

Significant improvements in joint function, pain, quality of life, and cartilage regeneration were observed in Re-Join®-treated knee OA patients with good tolerance in a period of 12 months.

Trial registration

ClinicalTrials.gov Identifier: NCT02162693. Registered 13 June 2014.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1248-3) contains supplementary material, which is available to authorized users.

Treatment of knee osteoarthritis with intra-articular injection of autologous adipose-derived mesenchymal progenitor cells: a prospective, randomized, double-blind, active-controlled, phase IIb clinical trial

OBJECTIVE

Human adipose-derived mesenchymal progenitor cells (haMPCs) are stem cells with multiple differentiation potential and immunomodulatory function. Re-Join® comprises in vitro expanded haMPCs from adipose tissue of patients combined with cell suspension solution. This study was undertaken to evaluate the efficacy and safety of Re-Join® in patients with symptomatic knee osteoarthritis (OA).

METHODS

Patients with Kellgren-Lawrence grade 1-3 knee OA were recruited from two centers and randomized to receive intra-articular injection of Re-Join® or HA. Pain and function were assessed by using WOMAC score, VAS, and SF-36. Magnetic resonance imaging (MRI) analysis was performed to measure cartilage repair. Adverse events (AEs) were collected.

RESULTS

Fifty-three patients were randomized. Significant improvements in WOMAC, VAS, and SF-36 scores were observed in both groups at months 6 and 12 compared with baseline. Compared with the HA group, significantly more patients achieved 50% improvement of WOMAC and a trend of more patients achieved a 70% improvement rate in Re-Join® group after 12 months. Meanwhile, there was notably more increase in articular cartilage volume of both knees in the Re-Join® group than in the HA group after 12 months as measured by MRI. AEs were comparable between two groups. Most AEs were mild and moderate except one SAE of right knee joint infection in the HA group.

CONCLUSIONS

Significant improvements in joint function, pain, quality of life, and cartilage regeneration were observed in Re-Join®-treated knee OA patients with good tolerance in a period of 12 months.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02162693 . Registered 13 June 2014.

Application of mesenchymal stem cell therapy for the treatment of osteoarthritis of the knee: A concise review

Osteoarthritis (OA) refers to a chronic joint disease characterized by degenerative changes of articular cartilage and secondary bone hyperplasia. Since articular cartilage has a special structure, namely the absence of blood vessels as well as the low conversion rate of chondrocytes in the cartilage matrix, the treatment faces numerous clinical challenges. Traditional OA treatment (e.g., arthroscopic debridement, microfracture, autologous or allogeneic cartilage transplantation, chondrocyte transplantation) is primarily symptomatic treatment and pain management, which cannot contribute to regenerating degenerated cartilage or reducing joint inflammation. Also, the generated mixed fibrous cartilage tissue is not the same as natural hyaline cartilage. Mesenchymal stem cells (MSCs) have turned into the most extensively explored new therapeutic drugs in cell-based OA treatment as a result of their ability to differentiate into chondrocytes and their immunomodulatory properties. In this study, the preliminary results of preclinical (OA animal model)/clinical trials regarding the effects of MSCs on cartilage repair of knee joints are briefly summarized, which lay a solid application basis for more and deeper clinical studies on cell-based OA treatment.

Up-regulation of FOXD1 by YAP alleviates senescence and osteoarthritis

Cellular senescence is a driver of various aging-associated disorders, including osteoarthritis. Here, we identified a critical role for Yes-associated protein (YAP), a major effector of Hippo signaling, in maintaining a younger state of human mesenchymal stem cells (hMSCs) and ameliorating osteoarthritis in mice. Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR associated protein 9 nuclease (Cas9)-mediated knockout (KO) of YAP in hMSCs resulted in premature cellular senescence. Mechanistically, YAP cooperated with TEA domain transcriptional factor (TEAD) to activate the expression of forkhead box D1 (FOXD1), a geroprotective protein. YAP deficiency led to the down-regulation of FOXD1. In turn, overexpression of YAP or FOXD1 rejuvenated aged hMSCs. Moreover, intra-articular administration of lentiviral vector encoding YAP or FOXD1 attenuated the development of osteoarthritis in mice. Collectively, our findings reveal YAP–FOXD1, a novel aging-associated regulatory axis, as a potential target for gene therapy to alleviate osteoarthritis.

The Hippo signalling effector YAP and the transcription factor FOXD1 play a role in alleviating cellular senescence and osteoarthritis, identifying the YAP-FOXD1 axis as a potential therapeutic target for aging-associated disorders.

Stem cell aging contributes to aging-associated degenerative diseases. Studies aiming to characterize the mechanisms of stem cell aging are critical for obtaining a comprehensive understanding of the aging process and developing novel strategies to treat aging-related diseases. As a prevalent aging-associated chronic joint disorder, osteoarthritis is a leading cause of disability. Senescent mesenchymal stem cells (MSCs) residing in the joint may be a critical target for the prevention of osteoarthritis; however, the key regulators of MSC senescence are little known, and targeting aging regulatory genes for the treatment of osteoarthritis has not yet been reported. Here, we show that Yes-associated protein (YAP), a major effector of Hippo signaling, represses human mesenchymal stem cell (hMSC) senescence through transcriptional up-regulation of forkhead box D1 (FOXD1). Lentiviral gene transfer of YAP or FOXD1 can rejuvenate aged hMSCs and ameliorate osteoarthritis symptoms in mouse models. We propose that the YAP–FOXD1 axis is a novel target for combating aging-associated diseases.

Argon plasma surface modification promotes the therapeutic angiogenesis and tissue formation of tissue-engineered scaffolds in vivo by adipose-derived stem cells

Background

Synthetic implants are being used to restore injured or damaged tissues following cancer resection and congenital diseases. However, the survival of large tissue implant replacements depends on their ability to support angiogenesis that if limited, causes extrusion and infection of the implant. This study assessed the beneficial effect of platelet-rich plasma (PRP) and adipose-derived stem cells (ADSCs) on synthetic biomaterials in combination with argon plasma surface modification to enhance vascularisation of tissue-engineered constructs.

Methods

Non-biodegradable polyurethane scaffolds were manufactured and modified with plasma surface modification using argon gas (PM). Donor rats were then used to extract ADSCs and PRP to modify the scaffolds further. Scaffolds with and without PM were modified with and without ADSCs and PRP and subcutaneously implanted in the dorsum of rats for 3 months. After 12 weeks, the scaffolds were excised and the degree of tissue integration using H&E staining and Masson’s trichrome staining, angiogenesis by CD31 and immune response by CD45 and CD68 immunohistochemistry staining was examined.

Results

H&E and Masson’s trichrome staining showed PM+PRP+ADSC and PM+ADSC scaffolds had the greatest tissue integration, but there was no significant difference between the two scaffolds (p < 0.05). The greatest vessel formation after 3 months was shown with PM+PRP+ADSC and PM+ADSC scaffolds using CD31 staining compared to all other scaffolds (p < 0.05). The CD45 and CD68 staining was similar between all scaffolds after 3 months showing the ADSCs or PRP had no effect on the immune response of the scaffolds.

Conclusions

Argon plasma surface modification enhanced the effect of adipose-derived stem cells effect on angiogenesis and tissue integration of polyurethane scaffolds. The combination of ADSCs and argon plasma modification may improve the survival of large tissue implants for regenerative applications.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1195-z) contains supplementary material, which is available to authorized users.

Reporting of Mesenchymal Stem Cell Preparation Protocols and Composition: A Systematic Review of the Clinical Orthopaedic Literature

BACKGROUND

Mesenchymal stem cells (MSCs) are increasingly being used in the treatment of a wide variety of sports-related conditions. Despite this enthusiasm, the biological properties of MSCs and their effects on musculoskeletal tissue healing remain poorly understood. MSC-based strategies encompass cell populations with heterogeneous phenotypes isolated from multiple tissues and using different methods. Therefore, comprehensive reporting of the source, preparation methods, and characteristics of MSC strategies is essential to enable interpretation of results.

PURPOSE

To perform a systematic review of levels of reporting of key variables in MSC preparation and composition for clinical studies evaluating MSC-based therapies in the treatment of musculoskeletal conditions.

STUDY DESIGN

Systematic review.

METHODS

A systematic review of the clinical orthopaedic and sports medicine literature from 2002 to 2017 was performed. The following inclusion criteria were used: human clinical trials, published in the English language, involving the administration of MSC-based therapies for orthopaedic or sports medicine applications. In vitro or ex vivo studies, editorials, letters to the editor, and studies relating to cosmetic, neurological, or dental applications were excluded.

RESULTS

Of the 1259 studies identified on the initial search, 36 studies were found to satisfy the inclusion criteria for analysis on comprehensive review. Fifty-seven percent of studies evaluated bone marrow-derived MSCs, 41% evaluated adipose-derived MSCs, and 2% evaluated synovium-derived MSCs. Considerable deficiencies in the reporting of key variables, including the details of stem cell processing, culture conditions, and the characteristics of cell populations delivered, were noted. Overall, studies reported only 52% (range, 30%-80%) of variables that may critically influence outcome. No study provided adequate information relating to all of these variables.

CONCLUSION

All existing clinical studies evaluating MSCs for orthopaedic or sports medicine applications are limited by inadequate reporting of both preparation protocols and composition. Deficient reporting of the variables that may critically influence outcome precludes interpretation, prevents others from reproducing experimental conditions, and makes comparisons across studies difficult. We encourage the adoption of emerging minimum reporting standards for clinical studies evaluating the use of MSCs in orthopaedics.

Bone Marrow-Derived and Adipose-Derived Mesenchymal Stem Cell Therapy in Primary Knee Osteoarthritis: A Narrative Review

Regenerative medicine in the context of musculoskeletal injury is a broad term that offers potential therapeutic solutions to restore or repair damaged tissue. The current focus in recent literature and clinical practice has been on cell based therapy. In particular, much attention has been centered on autologous bone marrow concentrate and adipose-derived mesenchymal stem cells (MSCs) for cartilage and tendon disorders. This article provides an overview of MSC-derived therapy and offers a comprehensive review of adipose- and bone marrow-derived MSC therapy in primary knee osteoarthritis. LEVEL OF EVIDENCE: IV.

Minimally Invasive and Regenerative Therapeutics

Advances in biomaterial synthesis and fabrication, stem cell biology, bioimaging, microsurgery procedures, and microscale technologies have made minimally invasive therapeutics a viable tool in regenerative medicine. Therapeutics, herein defined as cells, biomaterials, biomolecules, and their combinations, can be delivered in a minimally invasive way to regenerate different tissues in the body, such as bone, cartilage, pancreas, cardiac, skeletal muscle, liver, skin, and neural tissues. Sophisticated methods of tracking, sensing, and stimulation of therapeutics in vivo using nano-biomaterials and soft bioelectronic devices provide great opportunities to further develop minimally invasive and regenerative therapeutics (MIRET). In general, minimally invasive delivery methods offer high yield with low risk of complications and reduced costs compared to conventional delivery methods. Here, minimally invasive approaches for delivering regenerative therapeutics into the body are reviewed. The use of MIRET to treat different tissues and organs is described. Although some clinical trials have been performed using MIRET, it is hoped that such therapeutics find wider applications to treat patients. Finally, some future perspective and challenges for this emerging field are highlighted.

Treatment of Knee Osteoarthritis with Bone Marrow-Derived Mononuclear Cell Injection: 12-Month Follow-up

OBJECTIVES

To evaluate the main symptoms of knee osteoarthritis (OA) and tissue structure changes after a single dose bone marrow-derived mononuclear cell (BM MNC) intra articular injection. Case series study. Patients with knee OA Kellgren Lawrence (K-L) grade II and III received 1 injection of BM MNC. The clinical results were analyzed with the Knee injury and Osteoarthritis Outcome Score (KOOS) and Knee Society Score (KSS) before, 3, 6, and 12 months after injection. Radiological evaluation was performed with a calibrated x-ray and the magnetic resonance (MR) imaging before and 6 to 7 months postinjection.

RESULTS

A total of 34 knees were treated with BM MNC injections. Mean (±SD) age of patient group was 53.96 ± 14.15 years; there were 16 males, 16 females, KL grade II, 16; KL grade III, 18. The average injected count of BM MNCs was 45.56 ± 34.94 × 10⁶ cells. At the endpoint of 12 months 65% of patients still had minimal perceptible clinical improvement of the KOOS total score. The mean improvement of KOOS total score was +15.3 and of the KSS knee score was +21.45 and the function subscale +27.08 ( P < 0.05) points. The Whole Organ Magnetic Resonance Imaging Score (WORMS) improved from 44.31 to 42.93 points ( P < 0.05). No adverse effects after the BM-MNC injection were observed.

CONCLUSIONS

The single dose BM MNC partially reduces clinical signs of the knee osteoarthritis stage II/III and in some cases, decreases degenerative changes in the joint building tissue over 12-month period.

Arthroscopy Announces Annual Awards

Social media has transformed the way we communicate, including truncating the manner in which we converse. A positive result is that we are mindfully succinct as we acclaim our annual research prize winners. Just as investigations have limitations, we are limited in the number of publications that we can recognize. We are excited to celebrate our outstanding papers.

Adipose-Derived Stem Cell Treatments and Formulations

This article analyzes the current literature on the use of adipose-derived stem cells (ASCs) to evaluate the available evidence regarding their therapeutic potential in the treatment of cartilage pathology. Seventeen articles were included and analyzed, showing that there is overall a lack of high-quality evidence concerning the use of ASCs. Most trials are case series with short-term evaluation. The most adopted approach consists of an intra-articular injection of the stromal vascular fraction (SVF) rather than the expanded cells. Based on the available data, no specific preparation method or formulation could be considered as the preferred choice in clinical practice.

Intra-articular Mesenchymal Stem Cell Therapy for the Human Joint: A Systematic Review

BACKGROUND

Stem cell therapy is emerging as a potential treatment of osteoarthritis (OA) and chondral defects (CDs). However, there is a great deal of heterogeneity in the literature. The indications for stem cell use, the ideal tissue source, and the preferred outcome measures for stem cell-based treatments have yet to be determined.

PURPOSE

To provide clinicians with a comprehensive overview of the entire body of the current human literature investigating the safety and efficacy of intra-articular mesenchymal stem cell (MSC) therapy in all joints.

METHODS

To provide a comprehensive overview of the current literature, all clinical studies investigating the safety and efficacy of intra-articular MSC therapy were included. PubMed, MEDLINE, and Cochrane Library databases were searched for published human clinical trials involving the use of MSCs for the treatment of OA and CDs in all joints. A total of 3867 publications were screened.

RESULTS

Twenty-eight studies met the criteria to be included in this review. Fourteen studies treating osteoarthritis and 14 studies treating focal chondral defects were included. MSCs originating from bone marrow (13), adipose tissue (12), synovial tissue (2), or peripheral blood (2) were administered to 584 distinct individuals. MSCs were administered into the knee (523 knees), foot/ankle (61), and hip (5). The mean follow-up time was 24.4 months after MSC therapy. All studies reported improvement from baseline in at least 1 clinical outcome measure, and no study reported major adverse events attributable to MSC therapy.

DISCUSSION

The studies included in this review suggest that intra-articular MSC therapy is safe. While clinical and, in some cases, radiological improvements were reported for both OA and CD trials, the overall quality of the literature was poor, and heterogeneity and lack of reproducibility limit firm conclusions regarding the efficacy of these treatments.

CONCLUSION

This review provides strong evidence that autologous intra-articular MSC therapy is safe, with generally positive clinical outcomes.

Comparative advantages of infrapatellar fat pad: an emerging stem cell source for regenerative medicine

Growing evidence indicates that infrapatellar fat pad (IPFP)-derived stem cells (IPFSCs) exert robust proliferation capacities and multilineage differentiation potentials. However, few papers summarize the advantages that the IPFP and IPFSCs have in regenerative medicine. In this review we delineate the development and anatomy of the IPFP by comparing it with an adjacent fibrous tissue, synovium, and a more frequently harvested fat depot, subcutaneous adipose tissue. Furthermore, we explore the similarities and differences of stem cells from these three tissues in terms of IPFSCs, synovium-derived stem cells and subcutaneous adipose tissue-derived stem cells in proliferation capacity and tri-lineage differentiation potentials, including chondrogenesis, osteogenesis and adipogenesis. Finally, we highlight the advantages of IPFSCs in regenerative medicine, such as the abundant accessibility and the ability to resist inflammation and senescence, two hurdles for cell-based tissue regeneration. Considering the comparative advantages of IPFSCs, the IPFP can serve as an excellent stem cell source for regenerative medicine, particularly for cartilage regeneration.

Chasing Chimeras - The elusive stable chondrogenic phenotype

The choice of the best-suited cell population for the regeneration of damaged or diseased cartilage depends on the effectiveness of culture conditions (e.g. media supplements, three-dimensional scaffolds, mechanical stimulation, oxygen tension, co-culture systems) to induce stable chondrogenic phenotype. Herein, advances and shortfalls in in vitro, preclinical and clinical setting of various in vitro microenvironment modulators on maintaining chondrocyte phenotype or directing stem cells towards chondrogenic lineage are critically discussed. Chondrocytes possess low isolation efficiency, limited proliferative potential and rapid phenotypic drift in culture. Mesenchymal stem cells are relatively readily available, possess high proliferation potential, exhibit great chondrogenic differentiation capacity, but they tend to acquire a hypertrophic phenotype when exposed to chondrogenic stimuli. Embryonic and induced pluripotent stem cells, despite their promising in vitro and preclinical data, are still under-investigated. Although a stable chondrogenic phenotype remains elusive, recent advances in in vitro microenvironment modulators are likely to develop clinically- and commercially-relevant therapies in the years to come.

Intra-articular injections of expanded mesenchymal stem cells with and without addition of platelet-rich plasma are safe and effective for knee osteoarthritis

PURPOSE

To compare the effectiveness and safety of intra-articular injections of autologous expanded mesenchymal stromal stem cells alone (MSCs), or in combination with platelet-rich plasma (MSCs + PRP), in patients with knee osteoarthritis.

METHODS

Eighteen patients (57.6 ± 9.6 years) with radiographic symptomatic knee osteoarthritis (Dejour grades II-IV) were randomized to receive intra-articular injections of MSCs (n = 9) or MSCs + PRP (n = 9). Injections were performed 2-3 weeks after bone marrow aspiration (± 80-100 ml) which was obtained from both posterior iliac crests.

RESULTS

The Knee Injury and Osteoarthritis Outcome Score (KOOS) improved significantly throughout the 12 months for both groups (p < 0.05). No statistically significant differences between groups were found in KOOS subscales and global score improvements at 12-month end-point (n.s.). The MSCs group showed significant improvements in the pain, function and daily living activities, and sports and recreational activities subscales (p < 0.05). Similarly, the MSCs + PRP group showed significant improvements in the pain, function and daily living activities and quality of life subscales (p < 0.05). The average number of fibroblast colony forming units (CFU-F) was 56.8 + 21.9 for MSCs group and 50.7 ± 21.7 for MSCs + PRP group. Minimal adverse effects were seen in both groups (10 adverse events, in 5 patients).

CONCLUSIONS

Intra-articular injections of expanded MSCs alone or in combination with PRP are safe and have a beneficial effect on symptoms in patients with symptomatic knee osteoarthritis. Adding PRP to the MSCs injections did not provide additional benefit. These results are encouraging and support the recommendation of this minimally invasive procedure in patients with knee osteoarthritis, without requiring hospitalization. The CFU-F results may be used as reference for future research.

LEVEL OF EVIDENCE

Prospective cohort study, Level II.

Limited evidence for adipose-derived stem cell therapy on the treatment of osteoarthritis

PURPOSE

The purpose of this systematic review is to evaluate the effects of adipose derived mesenchymal stem cells (ADSCs) in the treatment of osteoarthritis (OA) in the clinical setting.

METHODS

A literature search was performed in the MEDLINE, EMBASE, and The Cochrane Library Database up to January 2017 for inclusion and exclusion criteria. Criteria for inclusion were clinical studies demonstrating the effects of ADSCs on OA, and written in English. The following variables were analyzed: donor site, volume of adipose tissue, preparation of ADSCs, clinical outcomes, and complication rate.

RESULTS

Sixteen studies (knee: 14 studies, multiple joints: 1 study, ankle: 1 study) were included in this systematic review. All of the studies prepared ADSCs in the form of the stromal vascular fraction (SVF). Inconsistencies between studies were found with regards to reported clinical variability, donor sites of SVF, and reported clinical outcomes. Nine studies used either platelet-rich plasma (PRP) (7/16) or fibrin (4/16) or both PRP and Fibrin (1/16), as an adjunct at time of SVF injection. All of the studies reported an improvement in clinical outcomes with the use of SVF. Five studies reported a 90% satisfaction rate, and no study reported any complications with liposuction. Five studies reported on complications, with a 5% incidence of swelling and pain.

CONCLUSIONS

This systematic review demonstrated that ADSCs are currently used in the form of SVF. While SVF may produce favorable clinical outcomes with minimal risk of side effects on osteoarthritis, the variability in the data and the use of biological adjuvants have confounded the effectiveness of ADSCs. This study will help surgeons understand the limitations in the literature on ADSCs.

LEVEL OF EVIDENCE

Level IV, systematic review of level IV studies.

Injectable Systems for Intra-Articular Delivery of Mesenchymal Stromal Cells for Cartilage Treatment: A Systematic Review of Preclinical and Clinical Evidence

Stem cell-based therapy is a promising approach to treat cartilage lesions and clinical benefits have been reported in a number of studies. However, the efficacy of cell injection procedures may be impaired by cell manipulation and damage as well as by cell dissemination to non-target tissues. To overcome such issues, mesenchymal stromal cell (MSC) delivery may be performed using injectable vehicles as containment systems that further provide a favorable cell microenvironment. The aim of this systematic review was to analyze the preclinical and clinical literature on platelet-rich plasma (PRP), hyaluronic acid (HA), and hydrogels for the delivery of MSCs. The systematic literature search was performed using the PubMed and Web of science databases with the following string: "(stem cells injection) AND (platelet rich plasma OR PRP OR platelet concentrate OR biomaterials OR hyaluronic acid OR hydrogels)": 40 studies (19 preclinical and 21 clinical) met the inclusion criteria. This review revealed an increasing interest on the use of injectable agents for MSC delivery. However, while negligible adverse events and promising clinical outcomes were generally reported, the prevalence of low quality studies hinders the possibility to demonstrate the real benefits of using such injectable systems. Specific studies must be designed to clearly demonstrate the added benefits of these systems to deliver MSCs for the treatment of cartilage lesions and osteoarthritis.

Injectable Systems for Intra-Articular Delivery of Mesenchymal Stromal Cells for Cartilage Treatment: A Systematic Review of Preclinical and Clinical Evidence

Stem cell-based therapy is a promising approach to treat cartilage lesions and clinical benefits have been reported in a number of studies. However, the efficacy of cell injection procedures may be impaired by cell manipulation and damage as well as by cell dissemination to non-target tissues. To overcome such issues, mesenchymal stromal cell (MSC) delivery may be performed using injectable vehicles as containment systems that further provide a favorable cell microenvironment. The aim of this systematic review was to analyze the preclinical and clinical literature on platelet-rich plasma (PRP), hyaluronic acid (HA), and hydrogels for the delivery of MSCs. The systematic literature search was performed using the PubMed and Web of science databases with the following string: "(stem cells injection) AND (platelet rich plasma OR PRP OR platelet concentrate OR biomaterials OR hyaluronic acid OR hydrogels)": 40 studies (19 preclinical and 21 clinical) met the inclusion criteria. This review revealed an increasing interest on the use of injectable agents for MSC delivery. However, while negligible adverse events and promising clinical outcomes were generally reported, the prevalence of low quality studies hinders the possibility to demonstrate the real benefits of using such injectable systems. Specific studies must be designed to clearly demonstrate the added benefits of these systems to deliver MSCs for the treatment of cartilage lesions and osteoarthritis.

Platelet-rich Plasma and Mesenchymal Stem Cells: Exciting, But … are we there Yet?

Joint conditions incapacitate free movement driving to a sedentary lifestyle, a major risk factor for chronic diseases. Regenerative procedures, involving the use of mesenchymal stem/stromal cells along with platelet-rich plasma (PRP), can help patients with these conditions. We describe the main characteristics of cellular products (bone marrow concentrate, stromal vascular fraction of adipose tissue, and mesenchymal stem/stromal cells derived from these tissues), and the potential benefits of combination with PRP in 3 scenarios: PRP lysates used during laboratory cell expansion; PRP to prime cellular products or the host tissue before cell implantation; PRP used as a vehicle for cell transplantation and to provide trophic signals. Clinical studies exploring the benefits of combination products are limited to case series and few controlled studies, involving either arthroscopy or percutaneous injections. Combination products are making their way to clinics but further experimental and clinical research is needed to establish protocols and indications.

Novel treatments for osteoarthritis: an update

Osteoarthritis is the most prevalent chronic joint condition worldwide. The principles of osteoarthritis treatment are to alleviate pain and stiffness as well as maintain function, with current consensus guidelines recommending the use of a combination of conservative measures including physical therapy, analgesia, and surgical interventions such as arthroplasty. In recent years, several pharmacological therapies have emerged as potential alternatives. Although a disease-modifying osteoarthritis drug has yet to be identified, promising results have been reported in recent trials especially with serotonin-norepinephrine reuptake inhibitors, IL-1 antagonists, and antibodies to nerve growth factor. The present review aims to summarize and discuss the latest results of novel treatments for osteoarthritis and potential targets for future research.

Effectiveness of mesenchymal stem cells for treating patients with knee osteoarthritis: a meta-analysis toward the establishment of effective regenerative rehabilitation

This systematic review with a meta-analysis aimed to summarize the current evidence of the effectiveness of mesenchymal stem cell (MSC) treatment for knee osteoarthritis (OA) and to examine whether rehabilitation is an effect modifier of the effect estimate of MSC treatment. A literature search yielded 659 studies, of which 35 studies met the inclusion criteria (n = 2385 patients; mean age: 36.0-74.5 years). The meta-analysis results suggested that MSC treatment through intra-articular injection or arthroscopic implantation significantly improved knee pain (standardized mean difference [SMD]: -1.45, 95% confidence interval [CI]: -1.94, -0.96), self-reported physical function (SMD: 1.50, 95% CI: 1.09, 1.92), and cartilage quality (SMD: -1.99; 95% CI: -3.51, -0.47). However, the MSC treatment efficacy on cartilage volume was limited (SMD: 0.49; 95% CI: -0.19, 1.16). Minor adverse events (knee pain or swelling) were reported with a wide-ranging prevalence of 2-60%; however, no severe adverse events occurred. The evidence for these outcomes was "very low" to "low" according to the Grades of Recommendation, Assessment, Development and Evaluation system because of the poor study design, high risk of bias, large heterogeneity, and wide 95% CI of the effects estimate. Performing rehabilitation was significantly associated with better SMD for self-reported physical function (regression coefficient: 0.881, 95% CI: 0.049, 1.712; P = 0.039). We suggest that more high quality randomized controlled trials with consideration of the potential rehabilitation-driven clinical benefit would be needed to facilitate the foundation of effective MSC treatment and regenerative rehabilitation for patients with knee OA.

Comparative Matched-Pair Analysis of Open-Wedge High Tibial Osteotomy With Versus Without an Injection of Adipose-Derived Mesenchymal Stem Cells for Varus Knee Osteoarthritis: Clinical and Second-Look Arthroscopic Results

BACKGROUND

High tibial osteotomy (HTO) is reported to be an effective treatment for varus knee osteoarthritis (OA) by redistributing the load line within the knee joint. The cell-based tissue engineering approach using mesenchymal stem cells (MSCs) has addressed the issue of articular cartilage repair in knee OA.

PURPOSE

This study aimed to compare the clinical, radiological, and second-look arthroscopic outcomes of open-wedge HTO with versus without an MSC injection and to identify the association between cartilage regeneration and HTO outcomes.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Among 271 patients treated with HTO for varus knee OA from September 2009 to April 2014, patients treated with HTO alone (conventional group; n = 50) were pair-matched with those who underwent HTO with an MSC injection (injection group; n = 50) based on sex, age, and lesion size. Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) score and Lysholm score. Radiological outcomes evaluated were the femorotibial angle and posterior tibial slope. At second-look arthroscopic surgery, cartilage regeneration was evaluated using the International Cartilage Repair Society (ICRS) grade.

RESULTS

At the time of second-look arthroscopic surgery (mean, 12.4 months [conventional group] and 12.7 months [injection group]), the mean IKDC and Lysholm scores in each group significantly improved: conventional group, from 38.4 ± 9.2 to 55.2 ± 15.0 and from 56.7 ± 12.2 to 79.6 ± 13.5, respectively; and injection group, from 36.5 ± 4.7 to 62.7 ± 14.1 and from 55.7 ± 11.9 to 80.6 ± 15.6, respectively ( P < .001 for all). Clinical outcomes at final follow-up (mean, 38.8 months [conventional group] and 37.2 months [injection group]) further improved from 62.7 ± 14.1 to 64.8 ± 13.4 (IKDC) and from 80.6 ± 15.6 to 84.7 ± 16.1 (Lysholm) ( P < .001 and P = .034, respectively) only in the injection group when compared with the values at second-look arthroscopic surgery. At final follow-up, there was a significant difference in the mean IKDC and Lysholm scores between groups ( P = .049 and P = .041, respectively). Overall ICRS grades, which significantly correlated with clinical outcomes, were better in the injection group than in the conventional group. Radiological outcomes at final follow-up showed improved knee joint alignment relative to patients' preoperative conditions but showed no significant correlation with clinical outcomes or ICRS grade in either group ( P > .05 for all).

CONCLUSION

The group that received an MSC injection scored better on the IKDC and Lysholm scales at final follow-up than the group that did not, although these differences were relatively small. When performing HTO for patients with varus knee OA, an MSC injection should be considered as an additional procedure for improved cartilage regeneration with better clinical outcomes.

Intra-articular injection of autologous adipose-derived stromal vascular fractions for knee osteoarthritis: a double-blind randomized self-controlled trial

OBJECTIVE

The purpose of this study was to compare the clinical and radiological efficacy of autologous adipose-derived stromal vascular fraction (SVF) versus hyaluronic acid in patients with bilateral knee osteoarthritis.

METHODS

Sixteen patients with bilateral symptomatic knee osteoarthritis (K-L grade II to III; initial pain evaluated at four or greater on a ten-point VAS score) were enrolled in this study, which were randomized into two groups. Each patient received 4-ml autologous adipose-derived SVF treatment (group test, n = 16) in one side of knee joints and a single dose of 4-ml hyaluronic acid treatment (group control, n = 16) in the other side. The clinical evaluations were performed pre-operatively and post-operatively at one month, three months, six months, and 12-months follow-up visit, using the ten-point visual analog scale (VAS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the knee range of motion (ROM). The whole-organ assessment of the knees was performed with whole-organ magnetic resonance imaging score (WORMS) based on MRI at baseline, six months and 12-months follow-up. The articular repair tissue was assessed quantitatively and qualitatively by magnetic resonance observation of cartilage repair tissue (MOCART) score based on follow-up MRI at six months and 12 months.

RESULTS

No significant baseline differences were found between two groups. Safety was confirmed with no severe adverse events observed during 12-months follow-up. The SVF-treated knees showed significantly improvement in the mean VAS, WOMAC scores, and ROM at 12-months follow-up visit compared with the baseline. In contrast, the mean VAS, WOMAC scores, and ROM of the control group became even worse but not significant from baseline to the last follow-up visit. WORMS and MOCART measurements revealed a significant improvement of articular cartilage repair in SVF-treated knees compared with hyaluronic acid-treated knees.

CONCLUSION

The results of this study suggest that autologous adipose-derived SVF treatment is safe and can effectively relief pain, improve function, and repair cartilage defects in patients with knee osteoarthritis.

[Bone void fillers in osteotomies : If, when, and which type?]

Medial opening wedge high tibial osteotomy (HTO) is an established procedure for treating medial osteoarthritis of the knee. In order to achieve the desired amount of correction, the osteotomy gap is opened, which creates a bone void in the medial aspect of the proximal tibia. The resulting bone void can either be left alone or be addressed by interposing a variety of different bone void fillers. Autologous and allogenic fillers can be distinguished from synthetic materials. Up to now, few studies have dealt with the usefulness and necessity for bone void fillers in HTO. The following article provides an overview on the currently used bone void fillers, their specific advantages and disadvantages and their influence on clinical and radiographic outcome after HTO.

Stem Cell Therapy for Articular Cartilage Repair: Review of the Entity of Cell Populations Used and the Result of the Clinical Application of Each Entity

BACKGROUND

Following successful preclinical studies, stem cell therapy is emerging as a candidate for the treatment of articular cartilage lesions. Because stem cell therapy for cartilage repair in humans is at an early phase, confusion and errors are found in the literature regarding use of the term stem cell therapy in this field.

PURPOSE

To provide an overview of the outcomes of cartilage repair, elucidating the various cell populations used, and thus reduce confusion with regard to using the term stem cell therapy.

STUDY DESIGN

Systematic review.

METHODS

The authors systematically reviewed any studies on clinical application of mesenchymal stem cells (MSCs) in human subjects. A comprehensive search was performed in MEDLINE, EMBASE, the Cochrane Library, CINAHL, Web of Science, and Scopus for human studies that evaluated articular cartilage repair with cell populations containing MSCs. These studies were classified as using bone marrow-derived MSCs, adipose tissue-derived MSCs, peripheral blood-derived MSCs, synovium-derived MSCs, and umbilical cord blood-derived MSCs according to the entity of cell population used.

RESULTS

Forty-six clinical studies were identified to focus on cartilage repair with MSCs: 20 studies with bone marrow-derived MSCs, 21 studies with adipose tissue-derived MSCs, 3 studies with peripheral blood-derived MSCs, 1 study with synovium-derived MSCs, and 1 study with umbilical cord blood-derived MSCs. All clinical studies reported that cartilage treated with MSCs showed favorable clinical outcomes in terms of clinical scores or cartilage repair evaluated by MRI. However, most studies were limited to case reports and case series. Among these 46 clinical studies, 18 studies erroneously referred to adipose tissue-derived stromal vascular fractions as "adipose-derived MSCs," 2 studies referred to peripheral blood-derived progenitor cells as "peripheral blood-derived MSCs," and 1 study referred to bone marrow aspirate concentrate as "bone marrow-derived MSCs."

CONCLUSION

Limited evidence is available regarding clinical benefit of stem cell therapy for articular cartilage repair. Because the literature contains substantial errors in describing the therapeutic cells used, researchers need to be alert and observant of proper terms, especially regarding whether the cells used were stem cells or cell populations containing a small portion of stem cells, to prevent confusion in understanding the results of a given stem cell-based therapy.

Current Concepts and Future Directions of Minimally Invasive Treatment for Knee Pain

PURPOSE OF REVIEW

The purpose of this paper is to review the percutaneous interventions available for the treatment of osteoarthrosis of the knee that address pain and prolong the time to arthroplasty.

RECENT FINDINGS

Corticosteroid injection and viscosupplementation have been the most studied, but there is still no consensus about their value. Thermal nerve ablation, including both radiofrequency ablation and cryoneurolysis, is a promising new modality of therapy that may increase in clinical use given current data showing favorable outcomes. Of the future therapies that are currently under investigation, synovial embolization via the geniculate arteries represents an exciting new approach that may soon be available clinically. There are various percutaneous interventions available for the treatment of osteoarthrosis of the knee that address pain and prolong the time to arthroplasty.

Regenerative Sports Medicine: Past, Present, and Future (Adapted From the PASSOR Legacy Award Presentation; AAPMR; October 2016)

Regenerative medicine has shown dramatic expanse and evolution in the past decade. Within that milieu, physiatrists are taking an active role in research, clinical care delivery, and education. The purpose of this review is to provide a balance among evidence, theory, experience, clinical trends, and the foreseeable future. We focus on the literature that reports the research with the best methodology in each practice area, recognizing that the level of evidence varies substantially among different treatment modalities and conditions. The following elements are included: an overview of the evolution of currently available regenerative techniques, evidence base for each available modality (prolotherapy, platelet rich plasma, bone marrow aspirate concentrate and stem cells, adipose-derived stem cells, and amniotic tissue products), general principles in the application of these treatments, and discussion and a vision of what lies ahead. We expect that practitioners will use this review to facilitate clinical decision making and to provide a core knowledge base to assist when counseling patients. LEVEL OF EVIDENCE: IV.

Eminent Sources of Adult Mesenchymal Stem Cells and Their Therapeutic Imminence

In the recent times, stem cell biology has garnered the attention of the scientific fraternity and the general public alike due to the immense therapeutic potential that it holds in the field of regenerative medicine. A breakthrough in this direction came with the isolation of stem cells from human embryo and their differentiation into cell types of all three germ layers. However, the isolation of mesenchymal stem cells from adult tissues proved to be advantageous over embryonic stem cells due to the ethical and immunological naivety. Mesenchymal Stem Cells (MSCs) isolated from the bone marrow were found to differentiate into multiple cell lineages with the help of appropriate differentiation factors. Furthermore, other sources of stem cells including adipose tissue, dental pulp, and breast milk have been identified. Newer sources of stem cells have been emerging recently and their clinical applications are also being studied. In this review, we examine the eminent sources of Mesenchymal Stem Cells (MSCs), their immunophenotypes, and therapeutic imminence.

Osteochondral repair using an acellular dermal matrix-pilot in vivo study in a rabbit osteochondral defect model

The aim of this pilot project was to introduce a novel use of acellular dermal matrix (ADM) in combination with infrapatellar fat pad mesenchymal stromal cells (IPFP-MSCs) to effect repair in a rabbit osteochondral defect model. ADM, in a range of surgical procedures, has been shown to promote remodelling of tissue at the site of implantation. Rabbit-derived ADM (rabADM) was prepared from the skin of donor rabbits. Autologous IPFP-MSCs were obtained at the time of knee surgery. Osteochondral defects (4 mm cartilage outer/2 mm central bone defect) were drilled into distal femoral condyles of 12 New Zealand White rabbits. Treatments groups: (i) defect only; (ii) rabADM alone; (iii) IPFP-MSCs alone; and (iv) rabADM with IPFP-MSCs. Condyles were harvested at 12 weeks, and analyzed using histology, immunohistochemistry (types I and II collagen) and histomorphometry to evaluate osteochondral repair. The rabADM only group achieved the highest ratio of type II to non-type II collagen (77.3%) using areal measures (similar to normal cartilage), which indicated a higher quality of cartilage repair. The addition of IPFP-MSCs, with or without rabADM, formed a fibrous collagen cap above the lesion site not seen with rabADM alone. Macroscopically, there was no joint erosion, inflammation, swelling or deformity, and all animals maintained full range of motion.

CONCLUSIONS

RabADM alone resulted in neocartilage formation similar to native cartilage. IPFP-MSCs limited osteochondral repair and contributed to fibrosis, even in combination with the rabADM. Further studies using ADM for osteochondral repair are warranted in a more appropriate pre-clinical model of osteochondral repair. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1919-1928, 2018.

Systemic and local adipose tissue in knee osteoarthritis

Knee osteoarthritis (OA) is the most common joint disease. Body adipose tissue has been shown to be related to the development and progression of knee OA. Among systemic adipose tissues, subcutaneous adipose tissue is significantly and negatively associated with muscle mass and forces, and could be related to the presence and progression of knee OA. Visceral adipose tissue is associated with increased cartilage loss and production of pro-inflammatory cytokines. Intra-muscular adipose tissue is associated with knee osteoarthritic changes, but it remains controversial if inter-muscular adipose tissue has a role to play in the pathogenesis for knee OA. Knee local adipose tissue such as infrapatellar fat pad (IPFP) can interact with neighbouring tissues, and may have a biphasic effect in knee OA. The underlying mechanisms for the roles of the systemic and local fat in knee OA could be related to biomechanical, metabolic, inflammatory factors and fat fibrosis, which may have a separated or combined effect on OA. Tissue engineering from systemic or local adipose tissue is a new research direction, and adipose tissue-derived stem cells from systemic or local adipose tissue may be beneficial for OA cartilage repair. Research on systemic and local adipose tissue would provide novel approaches for prevention and treatment of knee OA, but further studies are required to explore the roles of different adipose tissues in knee OA and the effects of stem cells derived from different adipose tissues on knee OA.

Biological Therapies in Regenerative Sports Medicine

Regenerative medicine seeks to harness the potential of cell biology for tissue replacement therapies, which will restore lost tissue functionality. Controlling and enhancing tissue healing is not just a matter of cells, but also of molecules and mechanical forces. We first describe the main biological technologies to boost musculoskeletal healing, including bone marrow and subcutaneous fat-derived regenerative products, as well as platelet-rich plasma and conditioned media. We provide some information describing possible mechanisms of action. We performed a literature search up to January 2016 searching for clinical outcomes following the use of cell therapies for sports conditions, tendons, and joints. The safety and efficacy of cell therapies for tendon conditions was examined in nine studies involving undifferentiated and differentiated (skin fibroblasts, tenocytes) cells. A total of 54 studies investigated the effects of mesenchymal stem-cell (MSC) products for joint conditions including anterior cruciate ligament, meniscus, and chondral lesions as well as osteoarthritis. In 22 studies, cellular products were injected intra-articularly, whereas in 32 studies MSC products were implanted during surgical/arthroscopic procedures. The heterogeneity of clinical conditions, cellular products, and approaches for delivery/implantation make comparability difficult. MSC products appear safe in the short- and mid-term, but studies with a long follow-up are scarce. Although the current number of randomized clinical studies is low, stem-cell products may have therapeutic potential. However, these regenerative technologies still need to be optimized.

Comparative Efficacy of Autologous Stromal Vascular Fraction and Autologous Adipose-Derived Mesenchymal Stem Cells Combined With Hyaluronic Acid for the Treatment of Sheep Osteoarthritis

The current study explored whether intra-articular (IA) injection of autologous adipose mesenchymal stem cells (ASCs) combined with hyaluronic acid (HA) achieved better therapeutic efficacy than autologous stromal vascular fraction (SVF) combined with HA to prevent osteoarthritis (OA) progression and determined how long autologous ASCs combined with HA must remain in the joint to observe efficacy. OA models were established by performing anterior cruciate ligament transection (ACLT) and medial meniscectomy (MM). Autologous SVF (1×10⁷ mononuclear cells), autologous low-dose ASCs (1×10⁷), and autologous high-dose ASCs (5×10⁷) combined with HA, and HA alone, or saline alone were injected into the OA model animals at 12 and 15 weeks after surgery, respectively. Compared with SVF+HA treatment, low-dose ASC+HA treatment yielded better magnetic resonance imaging (MRI) scores and macroscopic results, while the cartilage thickness of the tibial plateau did not differ between low, high ASC+HA and SVF+HA treatments detected by micro-computed tomography (µCT). Immunohistochemistry revealed that high-dose ASC+HA treatment rescued hypertrophic chondrocytes expressing collagen X in the deep area of articular cartilage. Western blotting analysis indicated the high- and low-dose ASC+HA groups expressed more collagen X than did the SVF+HA group. Enzyme-linked immunosorbent assay showed treatment with both ASC+HA and SVF+HA resulted in differing anti-inflammatory and trophic effects. Moreover, superparamagnetic iron oxide particle (SPIO)-labeled autologous ASC signals were detected by MRI at 2 and 18 weeks post-injection and were found in the lateral meniscus at 2 weeks and in the marrow cavity of the femoral condyle at 18 weeks post-injection. Thus, IA injection of autologous ASC+HA may demonstrate better efficacy than autologous SVF+HA in blocking OA progression and promoting cartilage regeneration, and autologous ASCs (5×10⁷ cells) combined with HA potentially survive for at least 18 weeks after IA injection.

Micro-fragmented adipose tissue for treatment of knee osteoarthritis with Baker's cyst: a case study

Adipose-derived therapies have increased in popularity for treatment of painful orthopaedic conditions, such as osteoarthritis. We report the passage of fat into a Baker’s cyst after injection of micro-fragmented adipose tissue in a patient with bilateral knee arthritis. Following fat grafting, the patient required drainage of fatty fluid from within the Baker’s cyst on multiple occasions. Approximately 3 months postprocedure, she began to notice an improvement in her knee pain with no further recurrence of pain or swelling from her Baker’s cyst.

Osteoarthritis and stem cell therapy in humans: a systematic review

OBJECTIVE

Osteoarthritis (OA) is a leading cause of disability in the world. Mesenchymal stem cells (MSCs) have been studied to treat OA. This review was performed to systematically assess the quality of literature and compare the procedural specifics surrounding MSC therapy for osteoarthritis.

DESIGN

PubMed, CINAHL, EMBASE and Cochrane Central Register of Controlled Trials were searched for studies using MSCs for OA treatment (final search December 2017). Outcomes of interest included study evidence level, patient demographics, MSC protocol, treatment results and adverse events. Level I and II evidence articles were further analyzed.

RESULTS

Sixty-one of 3,172 articles were identified. These studies treated 2,390 patients with osteoarthritis. Most used adipose-derived stem cells (ADSCs) (n = 29) or bone marrow-derived stem cells (BMSCs) (n = 30) though the preparation varied within group. 57% of the sixty-one studies were level IV evidence, leaving five level I and nine level II studies containing 288 patients to be further analyzed. Eight studies used BMSCs, five ADSCs and one peripheral blood stem cells (PBSCs). The risk of bias in these studies showed five level I studies at low risk with seven level II at moderate and two at high risk.

CONCLUSION

While studies support the notion that MSC therapy has a positive effect on OA patients, there is limited high quality evidence and long-term follow-up. The present study summarizes the specifics of high level evidence studies and identifies a lack of consistency, including a diversity of MSC preparations, and thus a lack of reproducibility amongst these articles' methods.

Intra-articular injection of mesenchymal stem cells in treating knee osteoarthritis: a systematic review of animal studies

PURPOSE

Mesenchymal stem cells (MSCs) injection has emerged as a novel treatment for knee osteoarthritis (KOA) but with inconsistent results in the experimental studies. Thus, the purpose of the present study is to evaluate the preclinical animal studies of MSCs injection for KOA and to determine the evidence for a role for MSCs in further clinical trials.

METHODS

A systematic search of KOA animal studies published through Aug 2017 was conducted using the PubMed, Embase and Web of science. Criteria for eligibility were animal studies assessing the therapeutic effects of MSCs intra-articular injection to animals with KOA. The methodological quality of included studies was assessed by the SYRCLE tool for assessing risk of bias in animal intervention studies. Descriptive synthesis was performed. Evidence quality was evaluated based on the Confidence in the Evidence from Reviews of Qualitative research (CERQual) tool.

RESULTS

Twenty-three KOA animal studies were eligible for inclusion. According to the SYRCLE's tool, all included studies had high risk of bias. Between-study heterogeneity was substantial. The included studies varied in terms of species, modeling methods, MSCs origin, treatment timing, injections frequency, transplantation type and dose of MSCs. The following outcomes, gross morphology, histological analysis, immunohistochemical analysis, radiological evaluation or behavior analysis, were reported in the primary studies. For all outcomes, the evidence quality was low or very low.

CONCLUSIONS

We do not have absolute confidence to recommend use MSCs injection for KOA clinical trials. Based on the internal and external validity of current animal studies, high quality experimental studies and efforts for effective translation from preclinical studies to clinical trials are still required.

Current Therapeutic Strategies for Stem Cell-Based Cartilage Regeneration

The process of cartilage destruction in the diarthrodial joint is progressive and irreversible. This destruction is extremely difficult to manage and frustrates researchers, clinicians, and patients. Patients often take medication to control their pain. Surgery is usually performed when pain becomes uncontrollable or joint function completely fails. There is an unmet clinical need for a regenerative strategy to treat cartilage defect without surgery due to the lack of a suitable regenerative strategy. Clinicians and scientists have tried to address this using stem cells, which have a regenerative potential in various tissues. Cartilage may be an ideal target for stem cell treatment because it has a notoriously poor regenerative potential. In this review, we describe past, present, and future strategies to regenerate cartilage in patients. Specifically, this review compares a surgical regenerative technique (microfracture) and cell therapy, cell therapy with and without a scaffold, and therapy with nonaggregated and aggregated cells. We also review the chondrogenic potential of cells according to their origin, including autologous chondrocytes, mesenchymal stem cells, and induced pluripotent stem cells.

Can photobiomodulation associated with implantation of mesenchymal adipose-derived stem cells attenuate the expression of MMPs and decrease degradation of type II collagen in an experimental model of osteoarthritis?

This study aimed to determine whether photobiomodulation therapy (PBMT) could improve the bioavailability and chondroprotective benefits of mesenchymal stem cells injected into the knees of rats used as an experimental model of osteoarthritis (OA) as well as reduce the expression of matrix metalloproteinases (MMPs) and degradation of type II collagen (COL2-1) in the cartilage. Adipose-derived stem/stromal cells (ADSCs) were collected from three male Fischer 344 rats and characterized by flow cytometry. Fifty female Fischer 344 rats were distributed into five groups of 10 animals each. These groups were as follows: control, OA, OA PBMT, OA ADSC, and OA ADSC PBMT. OA was induced in the animals using a 4% papain solution. Animals from the OA ADSC and OA ADSC PBMT groups received an intra-articular injection of 10 × 10⁶ ADSCs and were treated with PBMT by irradiation (wavelength: 808 nm, power: 50 mW, energy: 42 J, energy density: 71.2 J/cm², spot size: 0.028). Euthanasia was performed 7 days after the first treatment. The use of PBMT alone and the injection of ADSCs resulted in downregulation of pro-inflammatory cytokines and MPs in cartilage compared to the OA group. PBMT and ADSCs caused upregulation of tissue inhibitors of MPs 1 and 2 and mRNA and protein expression of COL2-1 in cartilage compared to the OA group. The intra-articular injection of ADSCs and PBMT prevented joint degeneration resulting from COL2-1 degradation and modulated inflammation by downregulating cytokines and MMPs in the OA group.

Safety, tolerability and efficacy of intra-articular Progenza in knee osteoarthritis: a randomized double-blind placebo-controlled single ascending dose study

Background

Cell therapies are being investigated as potential disease modifying treatment options for osteoarthritis (OA). Progenza (PRG) comprises in vitro expanded mesenchymal stem cells derived from human donor adipose tissue combined with cell culture supernatant. The primary objective of this first-in-human study was to evaluate the safety and tolerability of PRG.

Methods

We conducted a single centre, randomized, double-blind, placebo-controlled, single ascending dose study. Twenty patients aged 40–65 years with symptomatic Kellgren–Lawrence grade 1–3 knee OA were treated in two cohorts and randomized 4:1 to PRG or placebo. Cohort 1: 3.9 million cells (PRG 3.9M, n = 8) or placebo (n = 2) and cohort 2: 6.7 million cells (PRG 6.7M, n = 8) or placebo (n = 2). Each patient received a single intra-articular injection and was followed-up for 12 months.

Results

The study population comprised 20 patients (placebo, n = 4; PRG 3.9M, n = 8; PRG 6.7M, n = 8). All patients reported at least one treatment-emergent adverse event (TEAE). The majority of events [143/169 (84.6%)] were mild with 34 (20.1%) being considered by the investigator to be treatment related. There were no serious AEs or withdrawals due to AEs during the study. There was a statistically significant within group improvement in VAS pain scores from baseline at all timepoints for the PRG combined group, with highly significant improvements seen at months 3, 6, 9 and 12 (p ≤ 0.005) while VAS pain scores in the placebo group showed marginal improvement. A statistically significant improvement was also seen in WOMAC pain subscale scores from baseline at all timepoints for the PRG combined group while a marginal improvement in the placebo group was not statistically significant. Between screening and month 12, there was no decrease in average lateral tibial cartilage volume in the PRG 3.9M group while the placebo group showed a statistically significant cartilage loss. This difference between the placebo and PRG 3.9M group was statistically significant (LSM difference 106.47 mm³, 95% CI 13.56 mm³, 199.37 mm³, p = 0.028).

Conclusion

When administered as a single intra-articular injection to patients with symptomatic knee OA, PRG was safe and well tolerated. Furthermore, measurable improvements in symptoms and knee structure outcomes warrant further studies on PRG’s potential for disease modification in OA.

Trial registration ANZCTR, ACTRN12615000439549. Date registered: 7th May 2015, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368355

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1420-z) contains supplementary material, which is available to authorized users.

Articular Cartilage Aging-Potential Regenerative Capacities of Cell Manipulation and Stem Cell Therapy

Changes in articular cartilage during the aging process are a stage of natural changes in the human body. Old age is the major risk factor for osteoarthritis but the disease does not have to be an inevitable consequence of aging. Chondrocytes are particularly prone to developing age-related changes. Changes in articular cartilage that take place in the course of aging include the acquisition of the senescence-associated secretory phenotype by chondrocytes, a decrease in the sensitivity of chondrocytes to growth factors, a destructive effect of chronic production of reactive oxygen species and the accumulation of the glycation end products. All of these factors affect the mechanical properties of articular cartilage. A better understanding of the underlying mechanisms in the process of articular cartilage aging may help to create new therapies aimed at slowing or inhibiting age-related modifications of articular cartilage. This paper presents the causes and consequences of cellular aging of chondrocytes and the biological therapeutic outlook for the regeneration of age-related changes of articular cartilage.

The Use of Vibrational Energy to Isolate Adipose-Derived Stem Cells

Background:

Adipose-derived stem cell (ADSC)–based treatments have the potential to treat numerous soft-tissue pathologies. It would be beneficial to develop an efficient and reliable intraoperative, nonenzymatic method of isolating ADSCs for clinical use. This study aims to determine the (1) viability and proliferative capacity of ADSCs after exposure to vibrational energies and (2) efficacy of vibrational energy as a method of ADSC isolation from surgically harvested infrapatellar fat pad (IFP).

Methods:

Cultured ADSCs were exposed to 15 minutes of vibration (60 Hz) with displacements ranging from 0 to 2.5 mm to assess cell viability and proliferation. Then, arthroscopically harvested adipose tissue (IFP; n = 5 patients) was filtered and centrifuged to separate the stromal vascular fraction, which was exposed to 15 minutes of vibration (60 Hz; 1.3 mm or 2.5 mm displacement). A viability analysis was then performed along with proliferation and apoptosis assays.

Results:

Vibration treatment at all displacements had no effect on the viability or proliferation of the cultured ADSCs compared with controls. There was an increased apoptosis rate between the 2.5 mm displacement group (7.53%) and controls (5.17%; P < 0.05) at day 1, but no difference at days 2, 3, and 14. ADSCs were not isolated from the IFP tissue after vibration treatment.

Conclusions:

ADSCs maintained viability and proliferative capacity after 15 minutes of vibration at 60 Hz and 2.5 mm displacement. ADSCs were not isolated harvested IFP tissue after the application of vibrational energy.

The Utility of Biologics, Osteotomy, and Cartilage Restoration in the Knee

The management of complex cartilage and meniscal pathology in young, athletic patients is extremely challenging. Joint preservation surgery is most difficult in patients with concomitant knee pathologies, including cartilage defects, meniscal deficiency, malalignment, and/or ligamentous insufficiency. Clinical decision making for these patients is further complicated by articular cartilage lesions, which often are incidental findings; therefore, treatment decisions must be based on the confirmed contribution of articular cartilage lesions to symptomatology. Surgical management of any of the aforementioned knee pathologies that is performed in isolation typically results in acceptable patient outcomes; however, concomitant procedures for the management of concomitant knee pathologies often are essential to the success of any single procedure. The use of biologic therapy as an alternative to or to augment more conventional surgical management has increased in popularity in the past decade, and indications for biologic therapy continue to evolve. Orthopaedic surgeons should understand knee joint preservation techniques, including biologic and reconstructive approaches in young, high-demand patients.

Update on mesenchymal stem cell therapies for cartilage disorders

Cartilage disorders, including focal cartilage lesions, are among the most common clinical problems in orthopedic practice. Left untreated, large focal lesions may result in progression to osteoarthritis, with tremendous impact on the quality of life of affected individuals. Current management strategies have shown only a modest degree of success, while several upcoming interventions signify better outcomes in the future. Among these, stem cell therapies have been suggested as a promising new era for cartilage disorders. Certain characteristics of the stem cells, such as their potential to differentiate but also to support healing made them a fruitful candidate for lesions in cartilage, a tissue with poor healing capacity. The aim of this editorial is to provide an update on the recent advancements in the field of stem cell therapy for the management of focal cartilage defects. Our goal is to present recent basic science advances and to present the potential of the use of stem cells in novel clinical interventions towards enhancement of the treatment armamentarium for cartilage lesions. Furthermore, we highlight some thoughts for the future of cartilage regeneration and repair and to explore future perspectives for the next steps in the field.