Stromal Vascular Fraction in Osteoarthritis of the Knee

Efficacy of decellularized extracellular matrix (dECM) for articular cartilage repair in osteoarthritis (OA): a systematic review and meta-analysis

BACKGROUND

Osteoarthritis (OA) is a common degenerative joint disease causing chronic pain, disability, and mobility limitations, severely affecting quality of life. Traditional treatments like physical therapy and surgery often have limited efficacy due to side effects, incomplete recovery, and disease progression, highlighting the need for innovative therapies.

METHODS

We searched PubMed and Embase from January 1, 2010 to November 1, 2024, preliminary included studies involving animal experiments on the therapeutic effects of decellularized extracellular matrix (dECM) and its derived materials on cartilage defect. After removing duplicates, we conducted a bibliometric analysis. Following the exclusion and evaluation of literature, the random/fixed effects model was employed to perform meta-analysis and obtain Weighted Mean Difference (WMD) of Osteoarthritis Research Society International (OARSI) score and International Cartilage Repair Society (ICRS) score between the dECM treatment group and corresponding control group. We verify the robustness of the results through subgroup analysis and sensitivity analysis, with heterogeneity assessed by Q-test and quantified via I2 values.

RESULTS

We included a total of 10 studies, of which 7 were used for ICRS-based meta-analysis and 3 were used for OARSI-based meta-analysis. The combined mean ICRS of dECM treatment group/control group resulted in an WMD of 2.45 (95% CI: 1.07 to 3.84; I2 = 97.4%); P-value < 0.001). Meanwhile, the combined mean OARSI of dECM treatment group/control group resulted in an WMD of -1.65 (95% CI: -3.63 to 0.34; I2 = 97.3%). The subsequent funnel plot confirmed the low publication bias of the above results.

CONCLUSIONS

Based on the dual-index meta-analysis, the dECM and relative derivatives have been proved to possess significant cartilage repair function in OA, which can be further explored in tissue regeneration filed.

Enhancing Cartilage Repair in Osteoarthritis Using Platelet Lysates and Arthroscopic Microfracture

Background

Osteoarthritis (OA) is the most prevalent joint degenerative disease. MF is considered as a first-line treatment for OA. In the long term, the cartilage tissue regenerated after MF is fibrocartilage. In this study, we examine whether combined treatment of MF and Platelet lysate (PL) can inhibit promotion of cartilage repair and antifibrosis.

Methods

OA rat model established by the modified Hulth method. Rat PL injected into treated knee joints after MF surgery. The expression levels of metabolic and fibrosis molecules (Col2, Mmp13, Col1, Col3, α-SMA, and Ctgf) of chondrocytes were examined by immunohistochemistry. Cell immunofluorescence was used to assess bone marrow MSCs (BMSCs) proliferation. Transwell assays evaluated BMSCs migration, and qPCR and Western blot analyzed the mechanisms of PL. Moreover, a retrospective analysis was conducted to determine the clinical efficacy and safety of the combined treatment of MF and PL on OA patients.

Results

In vivo data showed that the combined treatment of MF and PL significantly alleviated joint pain, protected chondrocytes and inhibited synovial fibrosis on OA rats, as was confirmed by upregulation of Collagen II and downregulation of Mmp13, Col1, Col3, α-SMA, and Ctgf. Such anti-OA and antifibrosis effects of the combined treatment of MF and PL were superior to MF alone. In vitro data showed that PL induced cellular chondrogenic differentiation and migration of BMSCs, suggesting that PL facilitated stem cell homing to the cartilage injury sites and promoted cartilage repair and regeneration. Furthermore, the clinical data showed significant improvements of pain reduction and cartilage repair in OA patients.

Conclusion

This study demonstrated the anti-OA and antifibrosis effects of the combination of MF and PL, providing a promising synergistic therapeutic option for the treatment of OA.

The Regenerative Marriage Between High-Density Platelet-Rich Plasma and Adipose Tissue

The use of autologous biological preparations (ABPs) and their combinations fills the void in healthcare treatment options that exists between surgical procedures, like plastic reconstructive, cosmetic, and orthopedic surgeries; non-surgical musculoskeletal biological procedures; and current pharmaceutical treatments. ABPs, including high-density platelet-rich plasma (HD-PRP), bone marrow aspirate concentrates (BMACs), and adipose tissue preparations, with their unique stromal vascular fractions (SVFs), can play important roles in tissue regeneration and repair processes. They can be easily and safely prepared at the point of care. Healthcare professionals can employ ABPs to mimic the classical wound healing cascade, initiate the angiogenesis cascade, and induce tissue regenerative pathways, aiming to restore the integrity and function of damaged tissues. In this review, we will address combining autologous HD-PRP with adipose tissue, in particular the tissue stromal vascular fraction (t-SVF), as we believe that this biocellular combination demonstrates a synergistic effect, where the HD-PRP constituents enhance the regenerative potential of t-SVF and its adipose-derived mesenchymal stem cells (AD-MSCs) and pericytes, leading to improved functional tissue repair, tissue regeneration, and wound healing in variety of clinical applications. We will address some relevant platelet bio-physiological aspects, since these properties contribute to the synergistic effects of combining HD-PRP with t-SVF, promoting overall better outcomes in chronic inflammatory conditions, soft tissue repair, and tissue rejuvenation.

Clinical efficacy of cell-free fat extract and its effects on bone marrow edema in patients with early to mid-stage knee osteoarthritis: a clinical trial in comparison with hyaluronic acid

BACKGROUND

Previous studies have shown that hyaluronic acid can delay the progression of knee osteoarthritis. Existing research has extracted a bright red fluid called cell-free fat extract from human adipose tissue, which may play an important role in delaying the progression of osteoarthritis. By comparing with intra-articular injection of hyaluronic acid, this study aimed to evaluate the effects of intra-articular injection of CEFFE on both clinical efficacy and the reduction of bone marrow edema in patients with early to mid-stage knee osteoarthritis.

METHODS

A total of 48 patients with KOA (Kellgren-Lawrence grade II-III) symptoms were randomly divided into CEFFE group (24 cases) and HA group (24 cases). The patients in the CEFFE group received five injections of CEFFE (2 ml, 1 time/week), and the patients in the HA group received five injections of HA (2 ml, 1 ml/10 mg, 1 time/week). All the patients underwent clinical assessments using rating scales, including VAS, WOMAC and Lysholm Knee Score. These assessments were conducted at pre-treatment and at 3-week, 6-week, 3-month, and 6-month follow-up timepoints post-treatment. The clinical efficacy was evaluated at the 6-month follow-up after the treatment. The changes in subchondral bone marrow edema before and 6 months after treatment were assessed by grading BME on MRI of the affected knees.

RESULTS

A total of 52 knees from 46 patients were included in the final analysis. Comparison of VAS score, WOMAC score, and Lysholm score between the two groups revealed that the differences between pre-treatment and 3 weeks post-treatment were not statistically significant (P > 0.05). For the VAS score and WOMAC score at 6 weeks, 3 months, and 6 months post-treatment, the CEFFE group was lower than the HA group (P < 0.05). For the Lysholm score, the CEFFE group was higher than the HA group (P < 0.05). Compared with pre-treatment, VAS scores and WOMAC scores were lower and Lysholm scores were higher at all post-treatment time points (P < 0.05). At 6 months post-treatment, the clinical efficacy of the CEFFE group was significantly better than that of the HA group (P < 0.05). At 6 months post-treatment, MRI grading showed that subchondral BME was reduced to different degrees in both groups, with the reduction being more pronounced in the CEFFE group (P < 0.05).

CONCLUSION

This study demonstrated that intra-articular injection of CEFFE into the knee joint could enhance the durability of tissue-specific cells (especially chondrocytes) and improve cellular metabolic processes, preventing the continued progression of osteoarthritis. Both CEFFE and HA were found to improve clinical symptoms and reduced subchondral bone marrow edema in the treatment of early to mid-stage knee osteoarthritis. However, CEFFE was more effective than HA in achieving these outcomes.

A meta-analysis and systematic review of the clinical efficacy and safety of platelet-rich plasma combined with hyaluronic acid (PRP + HA) versus PRP monotherapy for knee osteoarthritis (KOA)

INTRODUCTION

KOA, a chronic degenerative joint disease, is commonly treated with intra-articular HA and PRP, used alone or in combination. However, the efficacy and safety of combination therapy (PRP + HA) remain unclear.

AIM

The aim of this systematic review and meta-analysis is to assess the clinical effectiveness and safety profile of PRP + HA versus PRP monotherapy for KOA.

MATERIAL AND METHODS

A systematic search was conducted using four electronic databases (PubMed, EMBASE, Scopus, and Cochrane Library) to select publications published in peer-reviewed journals. The mean difference (MD) and risk ratio (RR) was calculated, along with their 95% confidence intervals. We assessed heterogeneity using Cochrane Q and I2statistics and the appropriate p-value. The analysis used RevMan 5.4. GRADE system was used for evidence assessment for each outcome parameter.

RESULTS

This meta-analysis of 11 RCTs (n = 1023 KOA patients) revealed that PRP + HA has substantial effectiveness than PRP alone in reducing OMAC total scores [MD -1.77 (95% CI -2.20 to - 1.34); I2 = 10%, and p < 0.001], VAS scores [MD -4.27 (95% CI -4.96 to - 3.58); I2 = 13%, and p < 0.001], and Lequesne index score [MD -5.48 (95% CI -6.56 to - 4.40); I2 = 16%, and p < 0.001], while increasing IKDC scores [MD -2.10 (95% CI -3.70 to - 0.50); I2 = 9%, and p = 0.01], with low risk of adverse events [RR 0.41 (95% CI 0.35 to 0.48); I2 = 12%, and p < 0.001].

CONCLUSION

This meta-analysis reveals that, for patients with KOA, PRP + HA therapy is safe and yields better outcomes in pain relief and functional improvement compared to PRP monotherapy.

Adipose-derived mesenchymal stem cells combined with platelet-rich plasma are superior options for the treatment of osteoarthritis

BACKGROUND

There is currently no definitive treatment for osteoarthritis. We examined the therapeutic effects and underlying mechanisms of platelet-rich plasma (PRP) and adipose-derived mesenchymal stem cells (ADSCs), individually or in combination, in a rat model of anterior cruciate ligament-induced degenerative osteoarthritis (OA) of the knee. This study seeks to advance clinical approaches to OA treatment.

METHODS

Eight- to nine-week-old male Sprague-Dawley (SD) rats were randomly assigned to two groups: (1) a normal control group (Group A) and (2) a model group. The control group received no treatment. The model group underwent treatment and was further subdivided into six groups: Group B (an injury control group), Group C (high-dose ADSCs), Group D (PRP combined with high-dose ADSCs), Group E (low-dose ADSCs), Group F (PRP combined with low-dose ADSCs), and Group G (PRP alone). PRP and/or ADSCs were administered via intra-articular injection on Days 7, 37, and 67 post-surgery. Daily observations recorded activity levels and behavior, while weight changes were monitored weekly. Digital radiography (DR) was conducted on Days 30, 60, and 90 post-surgery to assess joint surface and contour alterations. Histopathological examination and inflammatory factor analysis were performed on cartilage and synovial tissue.

RESULTS

No abnormal reactions were observed in any rats, and body weights increased as expected (P > 0.05). Significant differences in knee swelling rates and Wakitani scores were observed between Groups A and B (P < 0.01). Knee swelling rates also differed significantly between Group B and Groups C-G (P < 0.01). Wakitani scores decreased on Days 60 and 90 in Groups C-G. TNF-α and IL-1β expression levels were significantly higher in Group B compared to Group A (P < 0.05). Expression levels of these genes were significantly lower in Groups C-G than in Group B (P < 0.05).

CONCLUSIONS

Repeated intra-articular injections of PRP and ADSCs alleviated inflammation and pain, promoted tissue repair, and modulated immune responses in rats with surgically induced OA. The combination of PRP and ADSCs demonstrated enhanced therapeutic efficacy, suggesting its potential as a treatment option for OA.

Adipose-derived stem cells and knee osteoarthritis: New perspectives, old concerns

In this editorial, we comment on the paper by Muthu et al published in the recent issue of the journal. This editorial review focusses on the use of adipose-derived stem cells (ADSCs) in knee osteoarthritis treatment. We discuss the differences between the stromal vascular fraction and microfragmented adipose tissue and highlight the results of clinical studies comparing both treatments and the use of hyaluronic acid, platelet-rich plasma, and bone marrow aspirate concentrate. The use of expanded ADSCs is also discussed; moreover, concerns regarding treatment with ADSCs, particularly the heterogeneity of published studies and the need to standardize protocols to explore clinical potential is explored.

Understanding and controlling the variables for stromal vascular fraction therapy

In regenerative medicine, the isolation of mesenchymal stromal cells (MSCs) from the adipose tissue's stromal vascular fraction (SVF) is a critical area of study. Our review meticulously examines the isolation process of MSCs, starting with the extraction of adipose tissue. The choice of liposuction technique, anatomical site, and immediate processing are essential to maintain cell functionality. We delve into the intricacies of enzymatic digestion, emphasizing the fine-tuning of enzyme concentrations to maximize cell yield while preventing harm. The review then outlines the filtration and centrifugation techniques necessary for isolating a purified SVF, alongside cell viability assessments like flow cytometry, which are vital for confirming the efficacy of the isolated MSCs. We discuss the advantages and drawbacks of using autologous vs allogeneic SVF sources, touching upon immunocompatibility and logistical considerations, as well as the variability inherent in donor-derived cells. Anesthesia choices, the selection between hypodermic needles vs liposuction cannulas, and the role of adipose tissue lysers in achieving cellular dissociation are evaluated for their impact on SVF isolation. Centrifugation protocols are also analyzed for their part in ensuring the integrity of the SVF. The necessity for standardized MSC isolation protocols is highlighted, promoting reproducibility and successful clinical application. We encourage ongoing research to deepen the understanding of MSC biology and therapeutic action, aiming to further the field of regenerative medicine. The review concludes with a call for rigorous research, interdisciplinary collaboration, and strict adherence to ethical and regulatory standards to safeguard patient safety and optimize treatment outcomes with MSCs.