Intraarticular Injections of Mesenchymal Stem Cells in Knee Osteoarthritis: A Review of Their Current Molecular Mechanisms of Action and Their Efficacy

Decadal analysis of efficacy and safety profiles of mesenchymal stem cells from varied sources in knee osteoarthritis patients: A systematic review and network meta-analysis

OBJECTIVE

Knee Osteoarthritis (KOA) is a debilitating degenerative joint ailment afflicting millions of patients. Numerous studies have assessed the efficacy of mesenchymal stem cells (MSCs) derived from various sources for KOA treatment, yet direct comparisons are scarce and inconsistent. Furthermore, network meta-analysis (NMA) conclusions require updating, while the safety of MSCs therapy remains contentious. This study evaluates therapeutic approaches involving MSCs from different sources in patients with KOA through randomized controlled trials (RCTs) and cohort studies. The objective is to compare the effectiveness and safety of MSCs strategies from various sources for KOA treatment.

METHODS

A systematic literature review was conducted to identify RCTs and cohort studies comparing different sources of MSCs in KOA patients. A randomized effects network meta-analysis was used to concurrently evaluate both direct and indirect comparisons across all protocols.

RESULTS

The NMA included 16 RCTS and reported 1005 participants. Adipose-derived mesenchymal stem cells (AD-MSCs) were the most effective treatment, showing significant improvements in the Visual Analogue Scale (VAS), the Short Form 36 (SF-36 scale), the International Knee Literature Committee Knee Evaluation Scale (IKDC subjective scores), and the Knee Injury and OA Outcome Score (KOOS). The probabilities are P = 85.3, P = 70.5, P = 88 and P = 87, respectively. Compared with placebo, AD-MSCs resulted in a VAS Score (SMD 0.97; 95%CI 0.37, 1.57), IKDC subjective scores (SMD -0.71; 95%CI -1.20, -0.21) was significantly reduced. Umbilical cord-derived mesenchymal stem cells (UC-MSCs) showed significant improvements in the University of Western Ontario and McMaster University OA (WOMAC) (P = 91.4). Compared with placebo, UC-MSCs had a higher WOMAC Score (SMD 1.65; 95%CI 0.27, 3.03) and ranked first. Compared with MSCs, placebo emerged as the safer option (P = 74.9), with a notable reduction in AEs associated with HA treatment (RR 0.77; 95%CI 0.61, 0.97). AD-MSCs were found to have the least favorable impact on AEs with a probability of P = 13.3.

CONCLUSIONS

This network meta-analysis established that MSCs offer pain relief and enhance various knee scores in KOA patients compared to conventional treatment. It also identifies other therapeutic avenues warranting further exploration through high-quality studies. Nonetheless, it underscores the necessity to emphasize the potential complications and safety concerns associated with MSCs.

Zhuifeng Tougu capsules in the treatment of knee osteoarthritis (cold dampness obstruction syndrome): a randomized, double blind, multicenter clinical study

BACKGROUND

In Traditional Chinese Medicine (TCM) theory, cold dampness obstruction is one of the common syndromes of osteoarthritis. Therefore, in clinical practice, the main treatment methods are to dispel wind, remove dampness, and dissipate cold, used to treat knee osteoarthritis (KOA). This report describes a mulitercenter clinical study to assess Zhuifeng Tougu Capsule's efficacy and safety in the treatment of patients who are cold dampness obstruction syndrome in KOA, and to provide evidence-based medical for the rational use of Zhuifeng Tougu Capsules in clinical practice.

METHODS

This randomized, parallel group controlled, double-blind, double dummy trial will include a total of 215 KOA patients who meet the study criteria. 215 patients underwent 1:1 randomisation, with 107 cases assigned the experimental group (Zhuifeng Tougu Capsules + Glucosamine Sulfate Capsules Simulator) and 108 assigned the control group (Glucosamine Sulfate Capsules + Zhuifeng Tougu Capsules Simulator). After enrolment, patients received 12 weeks of treatment. The main efficacy measure is the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) pain score. Visual analogue scale (VAS) pain score, Self-condition assessment VAS score, WOMAC KOA score, TCM syndrome score and TCM syndrome efficacy, ESR level, CRP level, suprapatellar bursa effusion depth, use of rescue drugs, and safety indicators are secondary efficacy indicators.

RESULTS

Compared with before treatment, WOMAC pain score, VAS pain score, Self-condition assessment VAS score, WOMAC KOA score, and TCM syndrome score decreased significantly in both groups (P < 0.01). Also, the experimental group showed significant differences in the above indicators compared to control (P < 0.01). However, after treatment, no significant differences were showed in the ESR level, CRP level, and suprapatellar bursa effusion depth between the two groups (P > 0.05). No any serious adverse effects showed in the experimental group and control group.

CONCLUSIONS

Zhuifeng Tougu Capsules can effectively improve knee joint function and significantly alleviate the pain of KOA.

TRIAL REGISTRATION

Clinical trial registration was completed with the China Clinical Trial Registration Center for this research protocol (No. ChiCTR2000028750) on January 2, 2020.

A systematic review, umbrella review, and quality assessment on clinical translation of stem cell therapy for knee osteoarthritis: Are we there yet?

BACKGROUND

The success of stem cell therapy for knee osteoarthritis (KOA) in preclinical animal models has accelerated the pace of clinical translation. However, it remains uncertain whether the current scientific evidence supports the clinical application of stem cells in treating KOA. A comprehensive evaluation of the safety and efficacy of stem cell therapies and scientific evidence quality is necessary.

METHODS

Using "stem cells" and "knee osteoarthritis" as the search terms, several databases, including PubMed, Web of Science, Cochrane, Embase, and Clinicaltrials.gov, were searched on August 25, 2022, and updated on February 27, 2023. Clinical studies that reported adverse reactions (ARs) of stem cell therapy in KOA patients were included without limiting the type of studies. Quantitative systematic reviews of stem cell therapy for KOA that conducted meta-analysis were included. Two researchers conducted literature screening and data extraction independently, and the evidence quality was evaluated according to the Institute of Health Economics and AMSTAR 2 criteria.

RESULTS

Fifty clinical studies and 13 systematic reviews/meta-analyses (SRs/MAs) were included. Nineteen ARs were reported in 50 studies, including five knee-related ARs, seven common ARs, and seven other ARs. Some studies reported over 10% prevalence of knee pain (24.5%; 95% CI [14.7%, 35.7%]), knee effusion (12.5%; 95% CI [4.8%, 22.5%]), and knee swelling (11.9%; 95% CI [3.5%, 23.5%]). Additionally, two studies have reported cases of prostate cancer and breast tumors, respectively. However, these two studies suggest that stem cell therapy does not bring significant ARs to patients. SRs/MAs results revealed that stem cell therapy relieved pain in patients over time but did not improve knee function. However, current clinical studies have limited evidence regarding study objectives, test designs, and patient populations. Similarly, SRs/MAs have inadequate evidence regarding study design, risk of bias assessment, outcome description, comprehensive discussion, and potential conflicts of interest.

CONCLUSIONS

The inefficacy of stem cells, the risk of potential complications, and the limited quality of evidence from current studies precluded any recommendation for using stem cell products in patients with KOA. Clinical translation of stem cell therapies remains baseless and should be cautiously approached until more robust evidence is available. PROSPERO registration number: CRD42022355875.

Cell-based therapies have disease-modifying effects on osteoarthritis in animal models. A systematic review by the ESSKA Orthobiologic Initiative. Part 2: bone marrow-derived cell-based injectable therapies

PURPOSE

Aim of this systematic review was to determine if bone marrow-derived cell-based injectable therapies induce disease-modifying effects in joints affected by osteoarthritis (OA) in animal models.

METHODS

A systematic review was performed on three electronic databases (PubMed, Web of Science, Embase) according to PRISMA guidelines. A synthesis of the results was performed investigating disease-modifying effects in preclinical animal studies comparing injectable bone marrow-derived products with OA controls or other products, different formulations or injection intervals, and the combination with other products. The risk of bias was assessed according to the SYRCLE's tool.

RESULTS

Fifty-three studies were included (1819 animals) with an increasing publication trend over time. Expanded cells were used in 48 studies, point-of-care products in 3 studies, and both approaches were investigated in 2 studies. Among the 47 studies presenting results on the disease-modifying effects, 40 studies (85%) reported better results with bone marrow-derived products compared to OA controls, with positive findings evident in 14 out of 20 studies (70%) in macroscopic assessment, in 30 out of 41 studies (73%) in histological assessment, and in 10 out of 13 studies (77%) in immunohistochemical evaluations. Clinical evaluations showed positive results in 7 studies out of 9 (78%), positive imaging results in 11 studies out of 17 (65%), and positive biomarker results in 5 studies out of 10 (50%). While 36 out of 46 studies (78%) reported positive results at the cartilage level, only 3 out of 10 studies (30%) could detect positive changes at the synovial level. The risk of bias was low in 42% of items, unclear in 50%, and high in 8%.

CONCLUSION

This systematic review of preclinical studies demonstrated that intra-articular injections of bone marrow-derived products can induce disease-modifying effects in the treatment of OA, slowing down the progression of cartilage damage with benefits at macroscopic, histological, and immunohistochemical levels. Positive results have been also observed in terms of clinical and imaging findings, as well as in the modulation of inflammatory and cartilage biomarkers, while poor effects have been described on the synovial membrane. These findings are important to understand the potential of bone marrow-derived products and to guide further research to optimise their use in the clinical practice.

LEVEL OF EVIDENCE

II.