Regenerative Medicine for Knee Osteoarthritis - The Efficacy and Safety of Intra-Articular Platelet-Rich Plasma and Mesenchymal Stem Cells Injections: A Literature Review

Platelet lysate for the treatment of osteoarthritis: a systematic review of preclinical and clinical studies

Intra-articular injection-based therapy is often used aside conservative treatment and lifestyle modifications to manage knee osteoarthritis (KO) patients. Conventional injections contain steroids and hyaluronic acid, while more recently multipotential adult stem cell, platelet-rich plasma (PRP), and platelet lysate (PL) injections have been used to promote cartilage regeneration or repair. The aim of the current study is to analyse current evidence on PL injections for the treatment of KO and to determine if these are effective and how these perform compared to other injection regimens. The databases of Scopus, Embase, PubMed, Web of Science, and Cochrane Library were searched on 30 June 2023. Risk of bias was assessed using the SYRCLE tool for animal studies and Cochrane RoB 2 as well as ROBINS-I tool for human studies. Studies were included if these were in English, any year, and regarded animals with osteoarthritis (OA) or human adult patients with OA. In vitro trials and non-adult human studies were excluded. Results on OA symptom stage and severity, and pain were recorded. The research retrieved three human studies (n = 48, n = 25, n = 58) and four animal studies: one rabbit, two studies, and one rat study. PL was found to decrease KO symptoms at follow-up ≤ 1 year with respect to baseline levels and when compared to hyaluronic acid or platelet-rich plasma. Symptoms returned 6 months-1 year after the final administration, with studies showing peak efficacy at approximately 6 months. Animal studies showed clinical improvements, reduction of lameness, and partial effect on the cartilage regeneration of the seven studies, two had a high risk of bias, four were associated to some concerns, and one had low risk. A major source of bias in these studies was the use of questionnaires and scoring that could be subject to interpretation. Overall, PL was well-tolerated and showed efficacy comparable to PRP; when pain control was assessed, it showed similar efficacy compared to hyaluronic acid. These findings may support its use in clinical trials to confirm these initial findings; future research should also focus on the comparison with other non-surgical treatments, on a more detail of the potential regenerative properties, and to optimise the treatment schedule.

Cartilage responses to inflammatory stimuli and adipose stem/stromal cell-derived conditioned medium: Results from an ex vivo model

Introduction

Osteoarthritis (OA), a chronic inflammatory joint disorder, still lacks effective therapeutic interventions. Consequently, the development of convenient experimental models is crucial. Recently, research has focused on the plasticity of Mesenchymal Stem/stromal Cells, particularly adipose-derived ones (ASCs), in halting OA progression. This study investigates the therapeutic potential of a cell-free approach, ASC-derived conditioned medium (CM), in reversing cytokine-induced OA markers in an ex vivo model of human cartilage explants.

Methods

4 mm cartilage punches, derived from the femoral heads of patients undergoing total hip replacement, were treated with 10 ng/ml TNFα, 1 ng/ml IL-1β, or a combination of both, over a 3-day period. Analysis of OA-related markers, such as MMP activity, the release of NO and GAGs, and the expression of PTGS2, allowed for the selection of the most effective inflammatory stimulus. Subsequently, explants challenged with TNFα+IL-1β were exposed to CM, consisting of a pool of concentrated supernatants from 72-h cultured ASCs, in order to evaluate its effect on cartilage catabolism and inflammation.

Results

The 3-day treatment with both 10ng/ml TNFα and 1ng/ml IL-1β significantly increased MMP activity and NO release, without affecting GAG release. The addition of CM significantly downregulated the abnormal MMP activity induced by the inflammatory stimuli, while also mildly reducing MMP3, MMP13, and PTGS2 gene expression. Finally, SOX9 and COL2A1 were downregulated by the cytokines, and further decreased by CM.

Conclusion

The proposed cartilage explant model offers encouraging evidence of the therapeutic potential of ASC-derived CM against OA, and it could serve as a convenient ex vivo platform for drug screening.

Contralateral knee osteoarthritis is a risk factor for ipsilateral knee osteoarthritis progressing: a case control study

BACKGROUND

Knee osteoarthritis (KOA) is a highly disabling disease, and studying its progression is crucial. However, it is still unclear whether the progression of ipsilateral knee osteoarthritis is influenced by contralateral knee osteoarthritis.

METHODS

Data were collected from the OAI database and divided into two study cohorts (right/left KOA cohort). Each cohort had a target knee (right/left knee) and was further divided into two groups (exposure/control group). The demographic data of both cohorts were balanced at baseline by propensity score matching (PSM), and the data included rating scale and radiographic and clinical data. After checking for balance in the matched variables, we then compared the differences between the two groups in each cohort. Our primary focus was on the minimum joint space width (mJSW) of the target knee, which was measured four years after baseline. The secondary outcome was the arthroplasty rate of the target knee within nine years.

RESULTS

In this study, a total of 678 participants were enrolled and matched. After 1:1 PSM of the baseline demographic data, 98 participants in the right KOA cohort (RKOAC) were successfully matched, and 117 participants in the left KOA cohort (LKOAC) were successfully matched. Furthermore, the standardized mean difference (SMD) of the matched variables in both cohorts was less than 0.25. After analyzing the outcome metrics, we found that the target knee had a significantly lower mJSW in the fourth year after baseline and a significantly greater arthroplasty rate within nine years in the exposed group than in the control group. RKOAC: mJSW (exposure: 2.6(1.1 ~ 3.6) vs. control: 3.3(2.0 ~ 4.2), P < 0.05), arthroplasty rate (exposure: 14(14.3%) vs. control: 4(4.1%), P < 0.05); LKOAC: mJSW (exposure: 3.1(2 ~ 3.9) vs. control: 3.4(2.6 ~ 4.2), P < 0.05), arthroplasty rate (exposure: 16(13.7%) vs. control: 7(6%), P < 0.05).

CONCLUSIONS

Patients with knee osteoarthritis experienced greater progression of osteoarthritis when the contralateral knee was also affected.

Global trends and hotspots in the application of platelet-rich plasma in knee osteoarthritis: A bibliometric analysis from 2008 to 2022

Platelet-rich plasma (PRP) injection therapy holds great promise in improving knee cartilage repair. This bibliometric analysis aimed to explore the research landscape in the application of PRP for knee osteoarthritis (KOA) over the last 15 years. All articles investigating PRP in the application of KOA were retrieved from the web of science core collection. Publications were analyzed using R software, VOS Viewer, CiteSpace, Microsoft Excel, and an online bibliometric platform (https://bibliometric.com/). A total of 815 articles were identified, 6 articles from 2010 had the highest average number of citations in the local database. Filardo G., Kon E., Cole B.J., Marcacci M., and Di Martino A. are the top 5 authors based on the H-index. The "American Journal Of Sports Medicine" is the most authoritative journal in the field of PRP application in KOA. The United States is the global leader in this field, with European countries playing a pivotal role in collaborative exchanges. Taipei Medical University is the most prolific institution and Shahid Beheshti University Medical Sciences in Iran the fastest-rising institution. The keywords "Hyaluronic Acid," "cartilage," "growth factors," "mesenchymal stem cells," "intra-articular injection," "pain," "inflammation," "double-blind," "management," "placebo," "stromal cells," "rheumatoid arthritis," and "pathology" appeared most frequently. "Exercise," "volume," and "physical-activity" are the latest hot topics. Future trends in this field include the standardization of injection components, injection sites, and injection methods, the modulation of useful or harmful growth factor receptor expression, sports management, and the validation of contraindications to PRP.

Human umbilical cord mesenchymal stem cells promoting knee joint chondrogenesis for the treatment of knee osteoarthritis: a systematic review

PURPOSE

The onset of OA is affected by a variety of factors, which eventually lead to the loss of cartilage in the joints, the formation of osteophytes, the loss of normal knee mobility, and pain and discomfort, which seriously affects the quality of life. HUC-MSCs can promote cartilage production and have been widely used in research in the past decade. This article systematically summarizes that it is well used in basic research and clinical studies to promote inflammatory chondrogenesis in the treatment of OA. Provide a theoretical basis for clinical treatment.

PATIENTS AND METHODS

This study collected CNKI, Wanfang, PubMed, and articles related to the treatment of OA with HUC-MSCs since their publication, excluding non-basic and clinical studies such as reviews and meta-analysis. A total of 31 basic experimental studies and 12 clinical studies were included. Systematically analyze the effects of HUC-MSCs on inhibiting inflammatory factors, promoting chondrocyte production, and current clinical treatment.

RESULTS

HUC-MSCs can reduce inflammatory factors such as MMP-13, ADAMTS-5, IL-1β, IL-1, IL-6, TNF-α, induced conversion from M1 to M2 in OA to protect cartilage damage and reduce OA inflammation. Synthesize ColII, SOX9, and aggrecan at the same time to promote cartilage synthesis.

CONCLUSION

HUC-MSCs not only have typical stem cell biological characteristics, but also have rich sources and convenient material extraction. Compared with stem cells from other sources, HUC-MSCs have stronger proliferation, differentiation, and immune regulation abilities. Furthermore, there are no ethical issues associated with their use.

SAFETY

Primarily attributed to pain, the majority of individuals experience recovery within 24 h following injection. HUC-MSCs possess the ability to alleviate pain, enhance knee joint function, and potentially postpone the need for surgical intervention in both non-surgical and other cases, making them highly deserving of clinical promotion and application.

Porcine Platelet Lysate Intra-articular Knee Joint Injections for the Treatment of Rabbit Cartilage Lesions and Osteoarthritis

Purpose

At present, autologous platelet-derived therapies such as platelet-rich plasma is widely used in the clinic, but allogeneic and xenogeneic therapies are currently in the research stage, mainly due to their biocompatibility in vivo. Platelet lysates depleted of antigens such as blood cells are a potential solution for allogeneic or xenogeneic applications. Platelet lysates can successfully promote the growth and differentiation of xenogeneic cells in vitro, but in vivo data are not yet available. This study aims to evaluate whether porcine platelet lysate can effectively avoid inflammatory reaction in rabbit knee joint, and then treat cartilage defect and arthritis.

Methods

We developed porcine platelet lysates containing undetectable antigens such as blood cells and complement. For xenogeneic application, platelet lysate was injected into rabbit knee joints to observe joint responses. To examine cartilage repair, osteochondral defects were created in rabbit knee joints. Rabbits were sacrificed three months after treatment with platelet lysate to observe cartilage regeneration and arthritis.

Results

The tissue sections in the rabbit knee joints showed no inflammatory reaction. Furthermore, the injection of platelet lysate was found to effectively inhibit the formation of cartilage arthritis in rabbit knee joints.

Conclusion

Our experimental results show that xenogeneic platelet lysate is a safe and effective method in the treatment of arthritis, which can be used as a research basis for future medical applications. The use of xenogeneic platelet lysate for regenerative therapy in vivo is feasible.

Platelet Rich Plasma Injections for Knee Osteoarthritis Treatment: A Prospective Clinical Study

Background: The aim of this prospective study was to evaluate the efficacy and safety of Platelet Rich Plasma (PRP) injections in patients affected by knee osteoarthritis (KOA). An autologous blood product containing a high percentage of various growth factors (GFs), cytokines and modulating factors as PRP has shown promising results in achieving this goal. Methods: One hundred and fifty-three patients (72 males, mean age 59.06 ± 8.78, range 40−81 years old) from January 2018 to January 2020 received three consecutive PRP injections and completed the follow ups. Western Ontario and McMaster University Osteoarthritis index (WOMAC), Knee society score (KSS) and Visual Analogic Scale (VAS) were evaluated before PRP injection (T0), one month (T1), three months (T2) and six months (T3) after the treatment. All patients underwent baseline and at 6 months MRI and X-ray evaluation. Results: A statistically significant VAS, KSS and WOMAC reduction emerged in the comparison between evaluations (p < 0.05), MRI demonstrated non-statistically significant improvement in cartilage thickness for both tibial plate and femoral plate (p = 0.46 and p = 0.33 respectively), and no radiographic changes could be seen in any patients. Conclusions: PRP injection represents a valid conservative treatment to reduce pain, improve quality of life and functional scores even at midterm of 6 months follow-up.

Treatment of knee osteoarthritis with intra-articular injection of allogeneic adipose-derived stem cells (ADSCs) ELIXCYTE®: a phase I/II, randomized, active-control, single-blind, multiple-center clinical trial

Objective

To evaluate the safety and efficacy of intra-articular (IA) injection of allogeneic adipose-derived stem cells (ADSCs) ELIXCYTE® for knee osteoarthritis.

Methods

This was a patient-blind, randomized, active-control trial consisted of 4 arms including hyaluronic acid (HA) control and 3 ELIXCYTE® doses. A total of 64 subjects were screened, and 57 subjects were randomized. The primary endpoints included the changes from baseline to post-treatment visit of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score at Week 24 and the incidence of adverse events (AEs) and serious adverse events (SAEs).

Results

No ELIXCYTE®-related serious adverse events were reported during 96 weeks of follow-up and no suspected unexpected serious adverse reaction (SUSAR) or death was reported. The changes of the primary endpoint, WOMAC pain score at Week 24, showed significant differences in all ELIXCYTE® groups, as well as in HA groups between post-treatment visit and baseline. The ELIXCYTE® groups revealed significant decreases at Week 4 compared to HA group in WOMAC total scores, stiffness scores, functional limitation scores suggested the potential of ELIXCYTE® in earlier onset compared to those from HA. The significant differences of visual analog scale (VAS) pain score and Knee Society Clinical Rating System (KSCRS) functional activities score at Week 48 after ELIXCYTE® administration suggested the potential of ELIXCYTE® in the longer duration of the effectiveness compared to HA group.

Conclusions

ELIXCYTE® for knee osteoarthritis treatment was effective, safe, and well-tolerated. The efficacy results were showed that ELIXCYTE® conferred the earlier onset of reductions in pain scores and improvements in functional scores than HA group.

Trial registration: ClinicalTrials.gov Identifier: NCT02784964. Registered 16 May, 2016—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02784964

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02631-z.

Intra-Articular Hybrid Hyaluronic Acid Injection Treatment in Overweight Patients with Knee Osteoarthritis: A Single-Center, Open-Label, Prospective Study

Background: A BMI > 25 is the most decisive, albeit modifiable, risk factor for knee osteoarthritis (KOA). This study aimed at assessing the efficacy of intra-articular injections of hybrid hyaluronic acid (HA) complexes (Sinovial® H-L) for the treatment of KOA in overweight patients in terms of disease severity, cardiocirculatory capacity, and quality of life. Materials: In this single-site, open-label, prospective trial, 37 patients with symptomatic knee OA were assessed at baseline and 3 months after ultrasound-guided intra-articular injection of hybrid HA complexes (Sinovial® H-L). Results: Primary variables displaying a statistically significant improvement after treatment were pain (VAS), disease severity (WOMAC), and cardiopulmonary capacity (6 min walk test). Among secondary variables, quality of life (SF-12) improved significantly, as did analgesic intake for pain control. No statistically significant difference was observed in body fat and muscle mass percentage measured by bioelectrical impedance analysis. Conclusions: Intra-articular hybrid HA injections are significantly effective in improving OA-related disease severity, cardiopulmonary function, and analgesic intake. This supports the role of hybrid HA viscosupplementation as a nonpharmacological treatment to relieve pain, reduce disability, improve quality of life, and limit the risk of polypharmacy in overweight patients with knee OA.

Experimental Therapeutics for the Treatment of Osteoarthritis

Osteoarthritis (OA) therapy remains a large challenge since no causative treatment options are so far available. Despite some main pathways contributing to OA are identified its pathogenesis is still rudimentary understood. A plethora of therapeutically promising agents are currently tested in experimental OA research to find an opportunity to reverse OA-associated joint damage and prevent its progression. Hence, this review aims to summarize novelly emerging experimental approaches for OA. Due to the diversity of strategies shown only main aspects could be summarized here including herbal medicines, nanoparticular compounds, growth factors, hormones, antibody-, cell- and extracellular vesicle (EV)-based approaches, optimized tools for joint viscosupplementation, genetic regulators such as si- or miRNAs and promising combinations. An abundant multitude of compounds obtained from plants, environmental, autologous or synthetic sources have been identified with anabolic, anti-inflammatory, -catabolic and anti-apoptotic properties. Some ubiquitous signaling pathways such as wingless and Integration site-1 (Wnt), Sirtuin, Toll-like receptor (TLR), mammalian target of rapamycin (mTOR), Nuclear Factor (NF)-κB and complement are involved in OA and addressed by them. Hyaluronan (HA) provided benefit in OA since many decades, and novel HA formulations have been developed now with higher HA content and long-term stability achieved by cross-linking suitable to be combined with other agents such as components from herbals or chemokines to attract regenerative cells. pH- or inflammation-sensitive nanoparticular compounds could serve as versatile slow-release systems of active compounds, for example, miRNAs. Some light has been brought into the intimate regulatory network of small RNAs in the pathogenesis of OA which might be a novel avenue for OA therapy in future. Attraction of autologous regenerative cells by chemokines and exosome-based treatment strategies could also innovate OA therapy.