Cartilage Regeneration Using Human Umbilical Cord Blood Derived Mesenchymal Stem Cells: A Systematic Review and Meta-Analysis

Bionic ECM scaffolds for directional articular hyaline cartilage regeneration and long-term homeostasis maintenance

Cartilage defects play a key role in osteoarthritis, causing functional impairment as the disease progresses. Microfracture surgery is commonly used to treat articular cartilage defects, providing early pain relief and functional improvement. However, the blood clot formed during the procedure differs from the natural cartilage microenvironment, hindering hyaline cartilage formation and promoting fibrocartilage, which limits long-term outcomes. This study proposes combining a bionic flexible extracellular matrix (ECM) scaffold with microfracture surgery as a treatment for cartilage defects. By filling the microfracture site with the scaffold and thermosensitive agarose gel, we can anchor BMSCs leaking from the bone marrow while creating a 3D microenvironment that regulates stem cell differentiation. Our results show that the scaffold's mechanical strength is comparable to that of hyaline cartilage, offering excellent biomimetic properties and biocompatibility. In vitro, BMSCs migrating into the scaffold exhibited a survival rate of nearly 90 % by day 2, significantly higher than the 25 % survival rate in the control agarose gel group, with cells observed anchoring around the scaffold. In vivo, stem cells anchored to the scaffold successfully differentiated into articular hyaline cartilage, driven by the combined effects of the scaffold's physical structure and its contained cytokines. The generated hyaline cartilage maintains homeostasis over time, reducing the risk of fibrocartilage formation. This strategy addresses a key limitation of microfracture surgery, where regenerated cartilage is often fibrocartilage, offering a promising new approach for cartilage repair.

Treatment of osteoarthritic knee with high tibial osteotomy and allogeneic human umbilical cord blood-derived mesenchymal stem cells combined with hyaluronate hydrogel composite

BACKGROUND

Delaying total knee arthroplasty is crucial for middle-aged patients with severe osteoarthritis. The long-term outcomes of high tibial osteotomy (HTO) remain uncertain. Recently, mesenchymal stem cells (MSCs) have shown promising potential in enhancing cartilage regeneration. Therefore, this study aimed to assess cartilage regeneration following the implantation of allogeneic human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) with HTO.

METHODS

In this case series, ten patients underwent hUCB-MSC implantation with HTO. The median age was 58.50 (range: 57.00-60.00) years, and the mean body mass index was 27.81 (range: 24.42-32.24) kg/m2. Clinical outcomes, including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS), Physical Component Score (PCS) and Mental Component Score (MCS) from the 36-Item Short-Form Health Survey (SF-36), were evaluated 6 months, 1 year, and 2 years postoperatively. Cartilage status of the medial femoral condyle (MFC) was assessed during hardware removal surgery, at least 2 years after the initial procedure, and compared with preoperative MFC cartilage status regarding lesion size and International Cartilage Repair Society (ICRS) grade. Radiological assessments included the Kellgren-Lawrence (KL) grading system for medial compartment osteoarthritis and hip-knee-ankle (HKA) angle.

RESULTS

Significant improvements were observed in WOMAC scores (preoperative: 57.00 (range: 44.75-63.00), postoperative: 27.50 (range: 22.25-28.75)), VAS scores (preoperative: 66.25 (range: 48.00-74.25), postoperative: 26.25 (range: 14.50-31.13)), SF-36 PCS (preoperative: 27.97 (range: 26.64-31.25), postoperative: 55.31 (range: 51.64-62.50)), and SF-36 MCS (preoperative: 41.04 (range: 29.95-50.96), postoperative: 63.18 (range: 53.83-65.16)) 2 years postoperatively (p = 0.002, 0.002, 0.002, and 0.020, respectively). The MFC chondral lesion demonstrated significant improvement in both lesion size (preoperative: 7.00 cm² (range: 4.38-10.50 cm²), postoperative: 0.16 cm² (range: 0.00-1.75 cm²), p = 0.002) and ICRS grade (preoperative: 4 (range: 4-4), postoperative: 1 (range: 1-2.25), p = 0.002). Additionally, the KL grade significantly decreased from 3 (range: 3-3) preoperatively to 2 (range: 2-2) postoperatively, while the HKA angle was corrected from 7.50° (range: 7.00-10.25°) preoperatively to -1.00° (range: -3.5-0.00°) postoperatively.

CONCLUSIONS

hUCB-MSC implantation with HTO is an effective treatment for medial compartment osteoarthritis and varus deformities, resulting in significant improvements in cartilage regeneration and overall clinical outcomes.

TRIAL REGISTRATION

NCT04234412.

Successful Rehabilitation Following Stem Cell Therapy for Large Knee Osteochondritis Dissecans in an Adolescent Wrestler

CONTEXT

Detailed rehabilitation protocols after stem cell treatment are lacking. This case highlights the rehabilitation of a patient treated with human umbilical cord blood-derived mesenchymal stem cell implantation for a large osteochondritis dissecans lesion of the knee.

CASE PRESENTATION

A 17-year-old male adolescent wrestler experienced persistent left knee pain for 1 year, unresponsive to 6 months of conservative treatment. MRI revealed a large osteochondritis dissecans lesion (38 × 18 mm) in the lateral femoral condyle, which was treated with human umbilical cord blood-derived mesenchymal stem cell implantation.

MANAGEMENT AND OUTCOMES

Rehabilitation was conducted in 4 phases. The protection phase (1-8 wk) emphasized weight-bearing restrictions, continuous passive motion, and early gait training. The gait recovery phase (9-12 wk) incorporated stationary cycling and open kinetic chain exercises. During the maturation phase (13-24 wk), maximal strength and proprioception exercises were introduced with antigravity treadmill running. The final recovery phase (24-52 wk) focused on plyometric drills and sport-specific activities. Team training resumed at 32 weeks, and return to full competitive training occurred at 52 weeks. The limb symmetry index for isokinetic knee-extensor strength and single-leg hop test reached 95.2% and 97.9%, respectively, by 12 months, indicating near-complete functional recovery. The modified MRI of cartilage repair tissue score improved from 40 to 60 points between 1 and 3 years postsurgery. Second-look arthroscopy revealed an International Cartilage Repair Society grade 1 at 35 months. International Knee Documentation Committee scores increased from 17.2 preoperatively to 98.9 at 2 years, while visual analog scale scores decreased from 10 to 2 over 3 years.

CONCLUSIONS

Accelerated weight bearing, early gait training, and phased strength exercises facilitated substantial improvements in function and cartilage healing in an adolescent wrestler with a large osteochondritis dissecans lesion. Further studies with larger cohorts are recommended to confirm these findings.

Selection of Optimal Protocol for Decellularization of Extracellular Matrix of Mesenchymal Stromal Cells of Human Umbilical Cord Tissue

To obtain extracellular matrix (ECM) of umbilical cord multipotent mesenchymal stromal cells (UC-MSCs), six decellularization protocols were used, based on physical (freeze/thaw) and chemical (Triton-X100, CHAPS, SDS, and NP-40) methods. The quality of decellularization was assessed using phase-contrast and fluorescence microscopy, quantitative image analysis was performed as well. It was shown that protocols based on CHAPS/NH4OH and Triton X-100/NH4OH are optimal for decellularizing UC-MSC layers and provide high-quality ECM. The SDS-based protocol may be useful when certain requirements to matrix structure are specified. The presented data will be in demand for the development of biomedical products.

Promotion of osteochondral repair through immune microenvironment regulation and activation of endogenous chondrogenesis via the release of apoptotic vesicles from donor MSCs

Utilizing transplanted human umbilical cord mesenchymal stem cells (HUMSCs) for cartilage defects yielded advanced tissue regeneration, but the underlying mechanism remain elucidated. Early after HUMSCs delivery to the defects, we observed substantial apoptosis. The released apoptotic vesicles (apoVs) of HUMSCs promoted cartilage regeneration by alleviating the chondro-immune microenvironment. ApoVs triggered M2 polarization in macrophages while simultaneously facilitating the chondrogenic differentiation of endogenous MSCs. Mechanistically, in macrophages, miR-100-5p delivered by apoVs activated the MAPK/ERK signaling pathway to promote M2 polarization. In MSCs, let-7i-5p delivered by apoVs promoted chondrogenic differentiation by targeting the eEF2K/p38 MAPK axis. Consequently, a cell-free cartilage regeneration strategy using apoVs combined with a decellularized cartilage extracellular matrix (DCM) scaffold effectively promoted the regeneration of osteochondral defects. Overall, new mechanisms of cartilage regeneration by transplanted MSCs were unconcealed in this study. Moreover, we provided a novel experimental basis for cell-free tissue engineering-based cartilage regeneration utilizing apoVs.

Chondrogenic Potential of Umbilical Cord-Derived Mesenchymal Stromal Cells: Insights and Innovations

BACKGROUND

The advent of tissue engineering and regenerative medicine has introduced innovative approaches to treating degenerative and traumatic injuries, particularly in cartilage, a tissue with limited self-repair capabilities. Among the various stem cell sources, umbilical cord-derived mesenchymal stromal cells (UC-MSCs) have garnered significant interest due to their non-invasive collection, minimal ethical concerns, and robust regenerative potential, particularly in cartilage regeneration.

METHODS

A comprehensive literature review was conducted using multiple databases, including PubMed, Scopus, Web of Science, and Google Scholar. Search terms focused on "umbilical cordderived mesenchymal stromal cells," "chondrogenesis," "cartilage regeneration," and related topics. Studies published in the past two decades were included, with selection criteria emphasizing methodological rigor and relevance to UC-MSC chondrogenesis. The review synthesizes findings from various sources to provide a thorough analysis of the potential of UC-MSCs in cartilage tissue engineering.

RESULTS

UC-MSCs exhibit significant chondrogenic potential, supported by their ability to differentiate into chondrocytes under specific conditions. Recent advancements include the development of biomaterial scaffolds and the application of genetic engineering techniques, such as CRISPR/Cas9, to enhance chondrogenic differentiation. Despite these advancements, challenges remain in standardizing cell isolation techniques, scaling up production for clinical use, and ensuring the long-term functionality of regenerated cartilage.

CONCLUSION

UC-MSCs offer a promising solution for cartilage regeneration in the field of regenerative medicine. Ongoing research is focused on overcoming current challenges through the use of advanced technologies, including bioreactors and gene editing. Collaborative efforts among researchers, clinicians, and bioengineers are essential to translating the potential of UC-MSCs into effective clinical therapies, which could significantly advance tissue regeneration and therapeutic innovation.

Comparison of Pain and Complications between Outpatients and Inpatients Treated with Bone Marrow Aspirate Concentrate for Knee Osteoarthritis

Bone marrow aspirate concentrate (BMAC) has been increasingly used as an injectable treatment for knee osteoarthritis (OA). However, there remains a lack of studies on the pain and complications associated with BMAC treatment. This study compared the pain and complications of BMAC treatment between outpatients and inpatients with Kellgren-Lawrence grade II-III knee osteoarthritis (OA) during a follow-up period of ≥3 months. This study included 40 outpatients (40 knees) and 80 inpatients (80 knees) as controls who received BMAC articular injections for knee OA between December 2023 and March 2024. Outpatients were administered BMAC under local anesthesia alone, whereas inpatients were administered BMAC under local anesthesia and intravenous anesthesia. The outcomes were the visual analog scale (VAS) pain score during the BMAC procedure and the complications associated with harvest and injection sites. The mean VAS pain score in the outpatient group was significantly higher than that in the inpatient group during trocar insertion (5.2 vs. 1.3, p < 0.05) and bone marrow aspiration (6.2 vs. 1.4, p < 0.05), but it was similar between the two groups during BMAC injection (2.2 vs. 2.3, p = 0.858). Transient post-treatment complications were observed in 17.5% (7/40) of outpatients and 16.3% (13/80) of inpatients. No significant differences were observed in complications between the two groups, all of which were resolved within 2 months without any specific problem. Moreover, no major complications occurred in any group. In conclusion, outpatients who received only local anesthesia reported significant pain during BMAC treatment. The addition of intravenous anesthesia is necessary to alleviate pain during the BMAC procedure.

Periodontists and stem cell-based therapy for alveolar bone regeneration: A national survey

BACKGROUND

Stem cell-based therapy for bone regeneration has received attention in medical settings but has not yet been used in clinical practice for treating alveolar bone defects. The objectives of this study were to explore whether periodontists had heard about this approach, and if so how, how interested they were to learn about it, which attitudes and behavioral intentions they had related to using stem cell-based grafting, and what they would like to know before using this approach.

METHODS

Anonymous survey data were collected from 481 members of the American Academy of Periodontology (response rate: 19.41%).

RESULTS

Responses showed 35.3% had heard about stem cell-based therapy, mostly from publications (9.6%) and meetings (8.3%); 76.1% wanted to learn about it through in-person continuing education (CE) courses, 68.6% in online CE courses, and 57.1% from manuals; 73% considered this approach promising; and 54.9% preferred it to traditional approaches. It was important to them that it would result in more bone volume (93%), better bone quality (90.4%), and accelerated healing (83.2%). Also, 60.1% considered it likely/very likely that they would adopt this approach, 54% that patients would prefer it, and 62.1% that it would benefit their practice. When asked what they would like to know about this approach, information about short- and long-term outcomes, cost, and logistical considerations were most frequently named.

CONCLUSIONS

These findings provide the basis to develop educational interventions for periodontists about this novel approach and inform future research activities aimed to translate this approach to clinical practice.

Effects of genus Epimedium in the treatment of osteoarthritis and relevant signaling pathways

Osteoarthritis (OA) is a common chronic degenerative joint disease in clinical practice with a high prevalence, especially in the elderly. Traditional Chinese Medicine (TCM) believes that OA belongs to the category of "Bi syndrome" and the "bone Bi syndrome". The etiology and pathogenesis lie in the deficiency of the liver and kidney, the deficiency of Qi and blood, and external exposure to wind, cold, and dampness. Epimedium is a yang-reinforcing herb in TCM, which can tonify the liver and kidney, strengthen muscles and bones, dispel wind, cold and dampness, and can treat both the symptoms and the root cause of "bone Bi syndrome". In addition, Epimedium contains a large number of ingredients. Through modern science and technology, more than 270 compounds have been found in Epimedium, among which flavonoids are the main active ingredients. Therefore, our study will review the effects and mechanisms of genus Epimedium in treating OA from two aspects: (1) Introduction of Epimedium and its main active ingredients; (2) Effects of Epimedium and its active ingredients in treating OA and relevant signaling pathways, in order to provide more ideas for OA treatment.

Implication of Cellular Senescence in Osteoarthritis: A Study on Equine Synovial Fluid Mesenchymal Stromal Cells

Osteoarthritis (OA) is described as a chronic degenerative disease characterized by the loss of articular cartilage. Senescence is a natural cellular response to stressors. Beneficial in certain conditions, the accumulation of senescent cells has been implicated in the pathophysiology of many diseases associated with aging. Recently, it has been demonstrated that mesenchymal stem/stromal cells isolated from OA patients contain many senescent cells that inhibit cartilage regeneration. However, the link between cellular senescence in MSCs and OA progression is still debated. In this study, we aim to characterize and compare synovial fluid MSCs (sf-MSCs), isolated from OA joints, with healthy sf-MSCs, investigating the senescence hallmarks and how this state could affect cartilage repair. Sf-MSCs were isolated from tibiotarsal joints of healthy and diseased horses with an established diagnosis of OA with an age ranging from 8 to 14 years. Cells were cultured in vitro and characterized for cell proliferation assay, cell cycle analysis, ROS detection assay, ultrastructure analysis, and the expression of senescent markers. To evaluate the influence of senescence on chondrogenic differentiation, OA sf-MSCs were stimulated in vitro for up to 21 days with chondrogenic factors, and the expression of chondrogenic markers was compared with healthy sf-MSCs. Our findings demonstrated the presence of senescent sf-MSCs in OA joints with impaired chondrogenic differentiation abilities, which could have a potential influence on OA progression.