Assessment of safety and efficacy of intra-articular injection of stromal vascular fraction for the treatment of knee osteoarthritis-a systematic review

Non-enzymatic methods for isolation of stromal vascular fraction and adipose-derived stem cells: A systematic review

BACKGROUND

Adipose-derived stem cells (ADSCs) and the stromal vascular fraction (SVF) have garnered substantial interest in regenerative medicine due to their potential to treat a wide range of conditions. Traditional enzymatic methods for isolating these cells face challenges such as high costs, lengthy processing time, and regu-latory complexities.

AIM

This systematic review aimed to assess the efficacy and practicality of non-enzymatic, mechanical methods for isolating SVF and ADSCs, comparing these to conventional enzymatic approaches.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a comprehensive literature search was conducted across multiple databases. Studies were selected based on inclusion criteria focused on non-enzymatic isolation methods for SVF and ADSCs from adipose tissue. The risk of bias was assessed, and a qualitative synthesis of findings was performed due to the methodological heterogeneity of the included studies.

RESULTS

Nineteen studies met the inclusion criteria, highlighting various mechanical techniques such as centrifugation, vortexing, and ultrasonic cavitation. The review identified significant variability in cell yield and viability, and the integrity of isolated cells across different non-enzymatic methods compared to enzymatic procedures. Despite some advantages of mechanical methods, including reduced processing time and avoidance of enzymatic reagents, the evidence suggests a need for optimization to match the cell quality and therapeutic efficacy achievable with enzymatic isolation.

CONCLUSION

Non-enzymatic, mechanical methods offer a promising alternative to enzymatic isolation of SVF and ADSCs, potentially simplifying the isolation process and reducing regulatory hurdles. However, further research is necessary to standardize these techniques and ensure consistent, high-quality cell yields for clinical applications. The development of efficient, safe, and reproducible non-enzymatic isolation methods could significantly advance the field of regenerative medicine.

Global Research on Osteoarthritis During 1994-2023: A Scientometric Assessment of Publications and Citations

Introduction

This study presents a global research scenario in the broad domain of osteoarthritis (OA) research, using quantitative and qualitative publication and citation indicators.

Methods

The study is based on 45,368 global publications, sourced from the Scopus bibliographical database, covering three decades (1994-2023). We studied the performance of the top 12 developed and top 12 developing countries. The key countries, organizations and authors at national and international levels were identified. The broad subject areas and key journals contributing to global OA research were delineated, besides identifying the broad characteristics of highly cited papers in the field.

Results

The United States and China were the most productive countries, while the Netherlands and Canada made the largest citation impact. Harvard Medical School and the University of Sydney made the most contribution, while Boston University and Pfizer Inc., USA registered the highest citation impact. Hunter DJ and Guermazi A were the most productive authors, while Lohmander LS, and Hochberg MC registered the highest citation impact. Osteoarthritis and Cartilage (n = 4879) and Annals of the Rheumatic Diseases (n = 786) published the maximum papers, while Arthritis and Rheumatism and Nature Reviews Rheumatology registered the largest citation impact. The highly cited papers with 100 or more citations constituted 6.25% of the total publications.

Conclusions

There has been a systematic growth of publications on OA. The research on OA was mainly done in developed countries, with the maximum publications coming from the United States of America, China and Canada. The most impactful publications on OA were from the Netherlands, Canada and the United States of America.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-024-01111-9.

Efficacy of stromal vascular fraction for knee osteoarthritis: A prospective, single-centre, non-randomized study with 2 years follow-up

BACKGROUND

Current osteoarthritis (OA) treatments focus on symptom relief without addressing the underlying disease process. In regenerative medicine, current treatments have limitations. In regenerative medicine, more research is needed for intra-articular stromal vascular fraction (SVF) injections in OA, including dosage optimization, long-term efficacy, safety, comparisons with other treatments, and mechanism exploration.

AIM

To compare the efficacy of intra-articular SVF with corticosteroid (ICS) injections in patients with primary knee OA.

METHODS

The study included 50 patients with Kellgren-Lawrence grades II and III OA. Patients were randomly assigned (1:1) to receive either a single intra-articular SVF injection (group A) or a single intra-articular ICS (triamcinolone) (group B) injection. Patients were followed up at 1, 3, 6, 12, and 24 months. Visual analog score (VAS) and International Knee Documentation Committee (IKDC) scores were administered before the procedure and at all follow-ups. The safety of SVF in terms of adverse and severe adverse events was recorded. Statistical analysis was performed with SPSS Version 26.0, IBM Corp, Chicago, IL, United States.

RESULTS

Both groups had similar demographics and baseline clinical characteristics. Follow-up showed minor patient loss, resulting in 23 and 24 in groups A and B respectively. Group A experienced a notable reduction in pain, with VAS scores decreasing from 7.7 to 2.4 over 24 months, compared to a minor reduction from 7.8 to 6.2 in Group B. This difference in pain reduction in group A was statistically significant from the third month onwards. Additionally, Group A showed significant improvements in knee functionality, with IKDC scores rising from 33.4 to 83.10, whereas Group B saw a modest increase from 36.7 to 45.16. The improvement in Group A was statistically significant from 6 months and maintained through 24 months.

CONCLUSION

Our study demonstrated that intra-articular administration of SVF can lead to reduced pain and improved knee function in patients with primary knee OA. More adequately powered, multi-center, double-blinded, randomised clinical trials with longer follow-ups are needed to further establish safety and justify its clinical use.

Recent Trends in Adipose Tissue-Derived Injectable Therapies for Osteoarthritis: A Scoping Review of Animal Models

Background and Objectives: This scoping review investigates recent trends in adipose tissue-derived injectable therapies for osteoarthritis (OA) in animal models, focusing on minimally manipulated or lightly processed adipose tissue. By evaluating and examining the specific context in which these therapies were investigated across diverse animal OA models, this review aims to provide valuable insights that will inform and guide future research and clinical applications in the ongoing pursuit of effective treatments for osteoarthritis. Materials and Methods: This research conducted a comprehensive literature review of PubMed and Embase to determine studies about minimally manipulated adipose tissue-derived injectable therapies for osteoarthritis investigated using animal models. The primary search found 530 results. After excluding articles that focused on spontaneous osteoarthritis; on transfected, preconditioned, cultured, or co-cultured adipose-derived stem cells; and articles with unavailable full text, we included 11 articles in our review. Results: The examined therapies encompassed mechanical micro-fragmented adipose tissue (MFAT) and stromal vascular fraction (SVF) obtained via collagenase digestion and centrifugation. These interventions were evaluated across various animal models, including mice, rats, rabbits, and sheep with induced OA. Notably, more studies concentrated on surgically induced OA rather than chemically induced OA. The assessment of these therapies focused on elucidating their protective immunomodulatory, anti-inflammatory, and chondroregenerative potential through comprehensive evaluations, including macroscopic assessments, histological analyses, immunohistochemical examinations, and biochemical assays. Conclusions: This review provides a comprehensive analysis of adipose tissue-derived injectable therapies for osteoarthritis across diverse animal models. While revealing potential benefits and insights, the heterogeneity of data and the limited number of studies highlight the need for further research to formulate conclusive recommendations for clinical applications.

The Evolution and Future Trends of Stromal Vascular Fraction: A Bibliometric Analysis

The heterogeneous population of cells obtained from processed adipose tissue, known as stromal vascular fraction (SVF), exhibits immunomodulatory and angiogenic properties. The therapeutic efficacy of SVF has been substantiated in numerous diseases, instilling hope for its clinical application as a cellular therapy. This study aims to provide a comprehensive analysis of the scholarly literature on SVF, including its worldwide progression, highlighting significant literatures, temporal development, research clusters, current active topics, and emerging trends. The combination of CiteSpace, HistCite Pro, and VOS Viewer tools was used to analyze the SVF literature. The overall panorama of the field is elucidated in terms of publication count, timeline, institutional distribution, journal coverage, and authors' contributions. In addition, this analysis explores the literature and keywords through the lens of co-occurrence, citation, and co-citation frequencies. Clustering algorithms are used to track the trajectory of the literature further, providing insight into its development. The findings offer a comprehensive overview of the progress made in the SVF field, highlighting distinct phases of development: the "Seedling period" from 1980 to 2010, the "Panicle period" from 2011 to 2016, and the "Flowering period" from 2017 to 2023. Within these periods, the evolution of 10 clusters is unraveled, encompassing topics such as vascular disease, CD34 expression, adipose tissue macrophage in 2013, cell-assisted lipotransfer, and knee osteoarthritis. In summary, this bibliometric study, conducting a quantitative analysis of publications in SVF research, encompasses a global overview of research, an analysis of pivotal literature in the field, research hotspots, and emerging frontiers.

Intra-Articular Injection of Adipose-Derived Stromal Vascular Fraction in Osteoarthritic Temporomandibular Joints: Study Design of a Randomized Controlled Clinical Trial

INTRODUCTION

Temporomandibular joint (TMJ) osteoarthritis is a degenerative disease of the TMJ. It is characterized by progressive degradation of the extracellular matrix components of articular cartilage, with secondary inflammatory components leading to pain in the temporomandibular region and reduced mouth opening. Current treatments do not halt disease progression, hence the need for new therapies to reduce inflammation and, consequently, improve symptoms. The aim of our randomized controlled clinical trial protocol is to investigate the efficacy of adjuvant intra-articular injections of autologous tissue-like stromal vascular fraction (tSVF), compared to arthrocentesis alone, in reducing pain and improving mouth opening in TMJ osteoarthritis patients.

MATERIALS AND METHODS

The primary endpoint analysis will consist of the visual analogue scale (VAS) for pain. The secondary endpoint analyses will include maximal interincisal mouth opening measurements; assessment of oral health and mandibular function based on the oral health impact profile (OHIP) questionnaire and mandibular functional impairment questionnaire (MFIQ); complications during the follow up; synovial cytokine analysis at baseline and after 26 weeks; and nucleated cells and tSVF (immuno)histochemistry analyses of the intervention group.

DISCUSSION

Our randomized clinical trial protocol will be applied to evaluate the efficacy of a new promising tSVF injection therapy for TMJ osteoarthritis. The safety of intra-articular injections of tSVF has been proven for knee osteoarthritis. However, since a tSVF injection is considered a heterologous application of cell therapy, the regulatory requirements are strict, which makes medical ethical approval challenging.

Autologous microfragmented adipose tissue treatment of knee osteoarthritis demonstrates effectiveness in 68% of patients at 4-year follow-up

BACKGROUND

Adipose tissue-derived stem cells are an interesting therapeutic option for early knee osteoarthritis (OA) treatment due to their high plasticity, easiness of harvesting and rapidity of administration. The aim of this study was to evaluate the medium-term effectiveness and safety of Microfragmented Autologous Fat Tissue (MFAT) injection treatment at 4-year follow-up and to investigate potential correlations among patients' pre-treatment clinical condition and clinical outcomes to identify possible predicting factors for procedure success or failure.

PATIENTS AND METHODS

This is a prospective trial enrolling 46 patients with diagnosis of symptomatic knee OA and failure of previous conservative measures who underwent diagnostic arthroscopy and single autologous MFAT injection between June 2017 and July 2018. Patients were assessed with repeated clinical scoring systems at baseline, 6 months, 1 and 4 years after surgery. The evaluation included demographic characteristics, arthroscopic findings, and stem cell number from injected tissue.

RESULTS

No major complications were reported during follow-up period and there was a significant increase of Lysholm knee score from baseline value of 61.7 ± 13.8 to 79.5 ± 16.9 at 4 years (p < 0.001). The WOMAC score increased from a baseline value of 66.5 ± 14.7 to 82.8 ± 15.7 at 4 years (p < 0.001) and there was a significant decrease of VAS pain score from baseline value of 6.3 ± 1.5 to 3.5 ± 2.6 at 4-year follow-up (p < 0.001). ROM improved significantly from 118.4 ± 2.6 to 122.5 ± 2.5 at 12 months (p < 0.001), but did not improve at 4 years (p > 0.05). 15 patients (32.6%) were considered treatment failures, because they required secondary surgery, further injection therapy or experienced symptoms persistence. Patient with synovitis had 75% failure rate, although synovitis did not result as a statistically significant factor influencing clinical outcome up to 4-year follow-up (p = 0.058). Age, cartilage defects severity, BMI, concomitant procedures, and stem cell number from injected MFAT did not show any significant correlation with the results.

CONCLUSIONS

MFAT intra-articular injection is a safe procedure with positive improvements up to 4-year follow-up in patients with early knee OA. These findings suggest MFAT could be a minimally invasive treatment of early knee OA with durable benefits at mid-term evaluation.

TRIAL REGISTRATION

IRB number ID-3522.

Meta-analysis of the efficacy and safety of arthroscopic surgery associated with platelet-rich plasma infusion when treating knee osteoarthritis

OBJECTIVE

To assess the efficacy and safety of arthroscopic surgery associated with platelet-rich plasma (PRP) infusion in treating knee osteoarthritis (KOA).

METHODS

PubMed, EMBASE, ScienceDirect, Cochrane Library, China Knowledge Network Database, China VIP Database, Wanfang Database, and China Biomedical Literature Database online database were searched for the case-control trial of arthroscopic surgery associated with PRP infusion in patients with KOA. During the search period of January 2010 through May 2022, two researchers independently extracted the data. With RevMan5.3, we performed a meta-analysis on the collected data.

RESULTS

A total of six clinical controlled studies were included, including 333 individuals. Compared with the control group treated only by arthroscopic surgery, the results showed that the visual analogue scores of patients in the arthroscopic surgery and PRP infusion group were significantly lower at 3, 6 and 12 months after operation, and the Western Ontario and McMaster Universities Osteoarthritis Index were significantly lower at 3, 6 and 12 months after operation (p < .05). The meta-analysis of Hospital for Special Surgery (HSS) knee score and Lisum knee score (LKSS) showed that postoperative HSS score, LKSS score at 3, 6, and 12 months after operation, and SF-36 quality of life score at 6 and 12 months after operation were higher (p < .05).

CONCLUSION

Arthroscopic debridement associated with PRP is more successful in relieving knee pain and enhancing knee joint function than arthroscopic debridement in treating KOA. The treatment scheme deserves to be popularized in clinical practice, but further research and longer interventions will be needed to validate it, using high-quality methods.

Stromal Vascular Fraction in Osteoarthritis of the Knee

In the United States, osteoarthritis (OA) affects 30 million people among the population and poses a major disability and financial burden that impact functional quality of life among the affected individuals [...].

Nanofat lysate ameliorates pain and cartilage degradation of osteoarthritis through activation of TGF-β-Smad2/3 signaling of chondrocytes

Introduction: Nanofat is an effective cell therapy for osteoarthritis (OA). However, it has clinical limitations due to its short half-life. We developed Nanofat lysate (NFL) to overcome the defect of Nanofat and explore its anti-OA efficacy and mechanism. Methods: Monoiodoacetate (MIA) was employed to establish rat OA model. For pain assessment, paw withdrawal latency (PWL) and thermal withdrawal latency (TWL) were evaluated. Degeneration of cartilage was observed by histopathological and immunohistochemical examination. Primary chondrocytes were treated with TNF-α to establish the cellular model of OA. MTT, wound healing, and transwell assays were performed to assess effects of NFL on chondrocytes. RNA-seq, qPCR and Western blot assays were conducted to clarify the mechanism of NFL. Results and Discussion: The animal data showed that PWL and TWL values, Mankin's and OARSI scorings, and the Col2 expression in cartilage were significantly improved in the NFL-treated OA rats. The cellular data showed that NFL significantly improved the proliferation, wound healing, and migration of chondrocytes. The molecular data showed that NFL significantly restored the TNF-α-altered anabolic markers (Sox9, Col2 and ACAN) and catabolic markers (IL6 and Mmp13). The RNA-seq identified that TGF-β-Smad2/3 signaling pathway mediated the efficacy of NFL, which was verified by qPCR and Western blot that NFL significantly restored the abnormal expressions of TGFβR2, phosphorylated-Smad2, phosphorylated-Smad2/3, Col2, Mmp13 and Mmp3. After long-term storage, NFL exerted similar effects as its fresh type, indicating its advantage of storability. In sum, NFL was developed as a new therapeutic approach and its anti-OA efficacy and mechanism that mediated by TGF-β-Smad2/3 signaling was determined for the first time. Besides, the storability of NFL provided a substantial advantage than other living cell-based therapies.

Cartilage lesion size and number of stromal vascular fraction (SVF) cells strongly influenced the SVF implantation outcomes in patients with knee osteoarthritis

PURPOSE

This study evaluated outcomes in patients with knee osteoarthritis following stromal vascular fraction implantation and assessed the associated prognostic factors.

METHODS

We retrospectively evaluated 43 patients who underwent follow-up magnetic resonance imaging 12 months after stromal vascular fraction implantation for knee osteoarthritis. Pain was assessed using the visual analogue scale and measured at baseline and 1-, 3-, 6-, and 12-month follow-up appointments. In addition, cartilage repair was evaluated based on the Magnetic Resonance Observation of Cartilage Repair Tissue scoring system using the magnetic resonance imaging from the 12-month follow-up. Finally, we evaluated the effects of various factors on outcomes following stromal vascular fraction implantation.

RESULTS

Compared to the baseline value, the mean visual analogue scale score significantly and progressively decreased until 12 months post-treatment (P < 0.05 for all, except n.s. between the 1 and 3-month follow-ups). The mean Magnetic Resonance Observation of Cartilage Repair Tissue score was 70.5 ± 11.1. Furthermore, the mean visual analogue scale and Magnetic Resonance Observation of Cartilage Repair Tissue scores significantly correlated 12 months postoperatively (P = 0.002). Additionally, the cartilage lesion size and the number of stromal vascular fraction cells significantly correlated with the 12-month visual analogue scale scores and the Magnetic Resonance Observation of Cartilage Repair Tissue score. Multivariate analyses determined that the cartilage lesion size and the number of stromal vascular fraction cells had a high prognostic significance for unsatisfactory outcomes.

CONCLUSION

Stromal vascular fraction implantation improved pain and cartilage regeneration for patients with knee osteoarthritis. The cartilage lesion size and the number of stromal vascular fraction cells significantly influenced the postoperative outcomes. Thus, these findings may serve as a basis for preoperative surgical decisions.

LEVEL OF EVIDENCE

IV.

Volume index as a new measure of cartilage loss: a retrospective MRI-based study of chondral injury patterns in adult patients with knee pain

BACKGROUND

Knee pain is one of the commonest symptoms in patients who attend the Orthopaedic outpatient clinics. Chondral defects result in a painful knee. Incidence of chondral defect is reported to be between 5 and 10% over the age of 40. It is well documented that chondral defects can lead to osteoarthritis. Early detection of these lesions and cartilage repair surgery can delay the onset of osteoarthritis. The purpose of this study is to highlight the incidence, associations and correlations between opposing cartilage defects in patients who present to the knee clinic with pain.

METHODS

A retrospective analysis was carried out on patients who had Magnetic Resonance Imaging scans for painful knees between June 2017 and May 2019. About 227 consecutive knees were studied for the incidence of chondral defects, number of lesions, grade and size of lesion, geographical location and associated pathology in the knee.

RESULTS

All the 227 patients had chondral lesions. Most patients had 2-3 lesions (66.1%) with patellar lesions (76.6%) being the commonest followed by medial femoral condyle (59.9%). Significant correlation was found in grade and size between opposing surface lesions in patella-trochlea, Medial Femoral Condyle-Medial Tibial Plateau and Lateral Femoral Condyle-Lateral Tibial Plateau. Females were more predisposed to patella lesions. Significance between age and lesions were established.

CONCLUSION

Incidence of cartilage defects in the knee is very high. Kissing lesions must be considered when treating cartilage lesions. Volume index could be a promising method to quantify lesions.

Antioxidant PDA-PEG nanoparticles alleviate early osteoarthritis by inhibiting osteoclastogenesis and angiogenesis in subchondral bone

Accumulating evidence suggests that osteoclastogenesis and angiogenesis in subchondral bone are critical destructive factors in the initiation and progression of osteoarthritis (OA). Herein, methoxypolyethylene glycol amine (mPEG-NH2) modified polydopamine nanoparticles (PDA-PEG NPs) were synthesized for treating early OA. The cytotoxicity and reactive oxygen species (ROS) scavenging ability of PDA-PEG NPs were evaluated. The effects of PDA-PEG NPs on osteoclast differentiation and vessel formation were then evaluated. Further, PDA-PEG NPs were administrated to anterior cruciate ligament transection (ACLT)-induced OA mice. Results demonstrated that PDA-PEG NPs had low toxicity both in vitro and in vivo. PDA-PEG NPs could inhibit osteoclastogenesis via regulating nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Moreover, PDA-PEG NPs suppressed osteoclast-related angiogenesis via down-regulating platelet-derived growth factor-BB (PDGF-BB). In vivo, PDA-PEG NPs inhibited subchondral bone resorption and angiogenesis, further rescuing cartilage degradation in OA mice. In conclusion, we demonstrated that PDA-PEG NPs deployment could be a potential therapy for OA.

Graphical Abstract

Intraoperative Administration of Adipose Stromal Vascular Fraction Does Not Improve Functional Outcomes in Young Patients with Anterior Cruciate Ligament Reconstruction

Adipose stromal vascular fraction (SVF) has a versatile cellular system for biologically augmented therapies. However, there have been no clinical studies investigating the benefits of the augmentation of anterior cruciate ligament reconstruction (ACLR) with SVF. We conducted a retrospective study in assessing the effects of intraoperative SVF administration on the functional outcomes in young patients with ACLR. The enrolled patients were divided into the control group (ACLR only) and the SVF group (ACLR with SVF). The functional outcomes in both groups were assessed by the Lysholm knee scoring system, the Tegner activity scale, and the International Knee Documentation Committee (IKDC) subjective evaluation form, and compared at several time points during a 12-month follow-up. We found that the sex distribution and pre-surgery scores were similar in the two groups, whereas the mean age of the SVF group was higher than that of the control group (p = 0.046). The between-group analysis and generalized estimating equation model analysis revealed that, while patients in the SVF group significantly improved all their functional outcomes at 12 months after surgery, this improvement was not significantly different from the results of patients in the control group (Lysholm, p = 0.553; Tegner, p = 0.197; IKDC, p = 0.486). No side effects were observed in either group. We concluded that the intraoperative administration of SVF does not improve or accelerate functional recovery after ACLR in young patients.

Intra-articular injection of stromal vascular fraction for knee degenerative joint disease: a concise review of preclinical and clinical evidence

Autologous fat-derived stromal vascular fraction (SVF) is a mixed cell population that has been used for many years in regenerative plastic surgery. In terms of animal and clinical research, this concise review was performed to evaluate the efficacy of SVF in knee degenerative joint disease (KDJD), which could cause pain, disability and severely affect patients' lives. Thirteen studies retrieved and screened from the databases were included, including six animal studies and seven clinical trials. The meta-analysis of clinical research shows that intra-articular injection of SVF, in combination with adjuvant surgery, could alleviate pain and improve early functional recovery for patients with KDJD at Kellgren-Lawrence (KL) grades II-III.

Stromal vascular fraction therapy for knee osteoarthritis: a systematic review

Background:

Regenerative cell therapies, such as adipose-derived stromal vascular fraction (SVF), have been postulated as potential treatments for knee osteoarthritis (KOA).

Objectives:

To assess the efficacy and safety of SVF treatment against placebo and other standard therapies for treating KOA in adult patients.

Design:

A systematic review.

Data sources and methods:

We searched the following databases: MEDLINE via PubMed, Epistemonikos, PEDro, DynaMed, TripDatabase, Elsevier via Clinicalkey and Cochrane Controlled Trials Register. We included prospective interventional studies where treatment with SVF in adults with KOA was compared against placebo or other standard therapies, and results were objectively measured with at least one widely recognised osteoarthritis scale.

Results:

Among 266 studies published until May 2021, nine met our inclusion criteria. A total of 239 patients (274 knees) were included in our study. The follow-up ranged from 6 to 24 months. Six studies had a control group (only one being placebo). All studies showed that SVF improved pain and functionality measured, in most cases, with the visual analogue scale and the Western Ontario and McMaster Universities Osteoarthritis Index. In addition, five studies reported an improvement in anatomical structures, as detected in MR images. However, the number of cells contained in SVF varied substantially between different studies, which could induce a comparison bias.

Conclusion:

Although based on a small number of dissimilar studies, SVF was considered a safe treatment for KOA and could be promising in terms of pain, functionality and anatomical structure improvement. However, SVF products need to be standardised, the number of cells homogenised and the use of concomitant treatments reduced to establish proper comparisons.

Registration:

PROSPERO registration number: CRD42021284187.

Non-homologous use of adipose-derived cell and tissue therapies: Osteoarthritis as a case study

Adipose tissue is widely recognized as an abundant and accessible human tissue that serves as a source of cells and extracellular matrix scaffolds for regenerative surgical applications. Increasingly, orthopedic surgeons are turning to adipose tissue as a resource in their treatment of osteoarthritis and related conditions. In the U.S., the regulatory landscape governing the orthopedic surgical utilization of autologous and allogeneic adipose tissue remains complex. This manuscript reviews the Food and Drug Administration's nomenclature and guidance regarding adipose tissue products. Additionally, it surveys recent pre-clinical and clinical trial literature relating to the application of adipose-derived cells and tissues in the treatment of osteoarthritis.

Short-term results of intra-articular injections of stromal vascular fraction for early knee osteoarthritis

Background

In knee osteoarthritis, progressive degeneration of the articular cartilage surface produces disability and chronic pain. Intra-articular injections of stromal vascular fraction (SVF) could be an innovative approach to manage patients with early knee osteoarthritis.

Methods

Between June 2019 and November 2020, 123 patients were recruited to receive intra-articular injection of SVF. Radiographic evidence of degenerative joint disease was classified according to Kellgren and Lawrence grades. Knee injury and osteoarthritis outcome score (KOOS) and visual analog scale (VAS) were collected preoperatively, at 1 month, and after 6 months from injection.

Results

There was a statistically significant improvement of KOOS and VAS of all patients to 6 months (p < 0.05). The mean KOOS before injection was 51.4 ± 16.5, after 1 month it was 75.5 ± 15.8, and at 6 months it was 87.6 ± 7.7. Stratifying the mean KOOS according to Kellgren–Lawrence Grades, the difference remained statistically significant (p < 0.05). The patients’ mean VAS before injection was 6.5, after 1 month it was 3.5, and after 6 months it was 2.4. No complications were observed.

Conclusions

Intra-articular knee injection of SVF is safe and effective to ameliorate the clinical and functional scores in patients with early knee osteoarthritis for 6 months.

Attenuation of osteoarthritis progression through intra-articular injection of a combination of synovial membrane-derived MSCs (SMMSCs), platelet-rich plasma (PRP) and conditioned medium (secretome)

PURPOSE

Osteoarthritis (OA) as a progressive destructive disease of articular cartilage is the most common joint disease characterized by reduction of joint cartilage thickness, demolition of cartilage surface and new bone formation. To overcome these problems, the purpose of the current research was to evaluate and compare the in vivo effects of synovial membrane-derived mesenchymal stem cell (SMMSCs), platelet-rich plasma (PRP) and conditioned medium (secretome) on collagenase II-induced rat knee osteoarthritis (KOA) remedy.

METHODS

For the first step, SMMSCs were isolated and characterized. Also, secretome was collected from SMMSCs culture. Furthermore, PRP was collect from the rat heart venous blood. Second, two injection of collagenase II with an interval of 3 days was performed in the knee intra-articular space to induce osteoarthritis. Two weeks later, animals were randomly divided into 6 groups. Control group without treatment, positive group: taken an intra-articular sodium hyaluronate injection (0.1 ml), treatment groups taken an intra-articular injection of; treatment 1: SMMSCs (5 × 10⁶), treatment 2: SMMSCs (5 × 10⁶)/secretome (50 µl), treatment 3: SMMSCs (5 × 10⁶)/PRP (50 µl), and treatment 4: SMMSCs (5 × 10⁶)/ secretome (50 µl)/ PRP (50 µl). Three months later, rats were killed and the following assessments were executed: radiography, histopathology, and immunohistochemistry.

RESULTS

Our findings represented that a combination of the SMMSCs/secretome/PRP had a considerable effect on glycosaminoglycans (GAGs) and collagen II contents, articular cartilage preservation, compared with other groups. In addition, combination of the SMMSCs with PRP and secretome showed the lowest expression of mmp3, while SOX9 had the highest expression in comparison with other groups. Also, SMMSCs-injected groups demonstrated better results compared with positive and control groups.

CONCLUSIONS

Injecting a combination of the SMMSCs/secretome/PRP resulted in better efficacy in terms of joint space width, articular cartilage surface continuity and integrity, sub-chondral bone and ECM constituents such as collagen II. Indeed, transplantation of this combination could be considered as a preliminary therapy for clinical trial study in the future.

Articular cartilage repair & joint preservation: A review of the current status of biological approach

The articular cartilage of the joint is the thin viscoelastic layer of the connective tissue. It has a unique anatomy and physiology, which makes the repair of the articular cartilage damage more difficult and challenging due to its limited healing capacity. Increasing knowledge regarding the importance of articular cartilage for joint preservation has led to increased attention on early identification of cartilage damage as well as degeneration in order to delay osteoarthritis. There are various treatment modalities ranging from preventive management, physical therapy, pharmacological, non-pharmacological and surgical treatments exist in current literature. However most of the studies have limited long term follow up and mainly consists of small case series and case reports. This is an up to date concise review discussing the available management options for articular cartilage damage starting to lifestyle modification to pharmacotherapy, physiotherapy, and osteobiologics till various joint preservation techniques that have been in use currently.

Comparison of Clinical and Imaging Outcomes of Different Doses of Adipose-Derived Stromal Vascular Fraction Cell Treatment for Knee Osteoarthritis

Favorable clinical outcomes of intra-articular injection of adipose-derived stromal vascular fraction (SVF) cells for knee osteoarthritis (OA) have been reported, but the effects of different doses of SVF cells have not been examined. This study aimed to compare the short-term clinical and imaging outcomes of different doses of SVF cells for knee OA treatment. This study included 60 patients with knee OA who underwent intra-articular injection of SVF cells. The follow-up period was at least 12 months. Thirty patients received an intra-articular injection of 2.5×10⁷ SVF cells (low-dose group), and the remaining 30 patients received an intra-articular injection of 5.0×10⁷ SVF cells (high-dose group). Clinical evaluations were performed for the Knee injury and Osteoarthritis Outcome Score (KOOS). Imaging evaluations, including the magnetic resonance imaging Osteoarthritis Knee Score (MOAKS) features (bone marrow lesions, cartilage defects, osteophytes, Hoffa’s synovitis, and effusion synovitis), were also performed. All clinical and imaging evaluations were performed preoperatively and 12 months postoperatively and compared between the groups. In demographic data, no significant differences were found between the two groups. The total score of KOOS at 12 months postoperatively was significantly more favorable than the preoperative score in the high-dose groups. Pain and symptoms subscale scores of KOOS at 12 months postoperatively were significantly better in the high-dose group than in the low-dose group. The bone marrow lesions, Hoffa’s synovitis, and effusion synovitis improved approximately 30–40% at 12 months postoperatively compared to baseline in both groups. However, there were no significant differences in imaging evaluations between the two groups. In conclusion, the pain and symptoms subscale scores of KOOS from baseline to 12 months postoperatively improved better in the high-dose group than in the low-dose group. Our findings suggest that intra-articular injection of SVF cells for knee OA is an innovative approach.