Ethical and Practical Considerations for Integrating Cellular ("Stem Cell") Therapy into Clinical Practice

New considerations in selecting donors for dental pulp stem cells: a pilot study

BACKGROUND/PURPOSE

Tissue engineering based on stem cell therapy necessitates a substantial quantity of high-quality stem cells. However, current sources face limitations, including narrow donor pools, compromised biological properties due to cryopreservation, and cellular senescence resulting from in vitro passaging and expansion. This study examines the impact of mild periodontitis on the biological performance of dental pulp stem cells (DPSCs) to explore the potential of broadening the donor pool for these cells.

MATERIALS AND METHODS

The experiment included two variables: age and the presence of periodontitis. DPSCs were isolated from six healthy subjects and six patients with mild periodontitis. Healthy subjects were categorized into Groups A (28-32 years) and B (52-54 years), and patients with mild periodontitis were categorized into Groups C (31-33 years) and D (50-53 years). The analyses included cell morphology, proliferation rate, multilineage differentiation capacity, apoptosis, and surface marker expression.

RESULT

No significant differences in cell morphology, pluripotency, or senescence were observed between healthy controls and periodontitis patients across age groups. Additionally, data on proliferation, pluripotency, and senescence were not significantly different. In healthy subjects, increased age was correlated with more elongated, flattened, and broader cells, alongside greater heterogeneity and intercellular granules. The proliferation and differentiation capacities decreased, whereas the degree of apoptosis increased. Similar trends were noted in patients with periodontitis.

CONCLUSION

The biological properties of DPSCs remain unchanged in teeth with mild periodontitis, providing valuable insights for addressing the shortage of DPSCs in tissue engineering. Teeth with mild periodontitis have the potential to be pulp stem cell donors.

Advancements in Regenerative Therapies for Orthopedics: A Comprehensive Review of Platelet-Rich Plasma, Mesenchymal Stem Cells, Peptide Therapies, and Biomimetic Applications

Background/Objectives: Regenerative therapies have gained interest in orthopedic applications for their potential to enhance tissue regeneration, functional recovery, and pain modification. This review evaluates the clinical efficacy of platelet-rich plasma (PRP), mesenchymal stem cells (MSCs), peptide-based treatments, and biomimetic materials in orthopedic care, with a focus on pain reduction and functional outcomes. Methods: A structured literature search in PubMed (January 2009-January 2025) identified 160 studies. After applying inclusion criteria prioritizing randomized controlled trials (RCTs) and clinical trials, 59 studies were included: 20 on PRP, 20 on MSCs, 10 on peptide therapies, and 7 on biomimetics. Data extraction focused on pain reduction and functional recovery, with risk of bias assessed using the Cochrane Risk of Bias (RoB) tool and ROBINS-I tool. A random-effects meta-regression analysis was conducted to evaluate the impact of therapy type, sample size, and risk of bias on reported pain reduction outcomes. Results: Meta-regression analysis identified MSC therapy as the most effective intervention for pain reduction (β = 8.45, p < 0.05), with PRP and peptide-based therapies showing moderate improvements, and biomimetic therapies demonstrating the lowest effect. PRP provided short-term pain relief, particularly in acute injuries and tendon repair, though inconsistencies in preparation methods limited success in chronic conditions. MSC therapies demonstrated cartilage regeneration and early osteoarthritis improvement, but high costs and ethical concerns remain barriers to widespread adoption. Peptide-based therapies and biomimetic materials, including engineered scaffolds and autologous protein solutions, showed promise for infection control and wound healing, though further research is needed to optimize dosing, delivery methods, and long-term safety. Conclusions: Regenerative therapies offer significant potential in orthopedic care, with MSC therapies demonstrating the most reliable regenerative effects, PRP providing short-term symptomatic relief, and peptide-based and biomimetic treatments emerging as promising adjuncts. However, standardized protocols and large-scale clinical trials are needed to establish long-term efficacy and improve clinical translation for broader adoption.

Comparison of Early-Stage Knee Osteoarthritis Induced by Medial Meniscus Tear Versus Tibial Osteotomy in the Rat Model

OBJECTIVE

Medial meniscus tear (MMT) is a common method to induce osteoarthritis in rats, but mimics secondary osteoarthritis. A novel method of carrying out a medial wedge closing tibial osteotomy (TO) has been recently developed to induce primary osteoarthritis. This study aims to validate it, compared to MMT.

METHODS

Twenty rats were divided equally into 2 groups. Outcome measures such as histology graded according to Osteoarthritis Research Society International (OARSI) guidelines and computed tomography (CT) scans were analyzed at 6 weeks post-operatively. Observational gait analysis and serum biomarkers such as C-terminal cross-linked telopeptides of type II collagen (CTX-II) and interleukin-1 beta (IL-1β) were collected at 2-weekly intervals up to 6 weeks post-operatively.

RESULTS

Serum CTX-II and IL-1β levels did not reveal a statistically significant difference across all time points between the 2 groups. CT grading was significantly more severe (2.80 ± 1.10 vs 1.40 ± 0.548, P = 0.0389) in the MMT group compared to the TO group. In addition, histological gradings such as calcified cartilage score (2.10 ± 1.91 vs 0.00 ± 0.00, P < 0.01) and cartilage degeneration score (4.80 ± 5.18 vs 0.00 ± 0.00, P < 0.01) revealed significantly more severe osteoarthritis in the MMT compared to TO group. Synovial membrane score did not reveal a statistically significant difference (1.10 ± 0.994 vs 1.00 ± 0.00, P = 1.00).

CONCLUSION

TO is a novel method in inducing primary osteoarthritis in the rat model compared to MMT between the 6 and 12 weeks' time frame.

Time to Total Knee Arthroplasty (TKA) Post Intra-Articular Injection

Background: Disease-modifying treatments are not currently developed to target the underlying causes of knee osteoarthritis (KOA). Corticosteroids (CS), hyaluronic acid (HA), and platelet-rich plasma (PRP) intra-articular (IA) injections are commonly used for patients that do not respond to non-pharmacological treatments, oral nonsteroidal anti-inflammatory, or pain medications to address solely KOA symptoms. Utilizing TKA as an endpoint in the KOA disease progression provides a basis to determine efficacy of this treatment pathway. The primary objective is to evaluate a large national database to determine the time between first injection and total knee arthroplasty in patients solely administered intra-articular IA, CS, and HA. Methods: A retrospective query was performed on a national, all-payer claims database (PearlDiver, Colorado Springs, CO, USA), a composite of over 160 million Health Insurance Portability and Accountability Act compliant orthopedic records across all states and territories of the United States spanning 2016 to 2022. The database was queried to produce three distinct cohorts for analysis (PRP, HA, and CS). A 4:1 case match was conducted to compare cohorts receiving a subsequent TKA. Kaplan-Meier survival analysis analyzed the TKA-free survival of patients within each group at 6 months and 1 to 4 years. The log-rank test was performed for comparisons between survival cohorts. Results: The PRP cohort had a total population of 3240 patients, of which 71 (2.2%) received a subsequent TKA. The corticosteroid cohort had a total population of 1,382,572, of which 81,271 (5.9%) received a subsequent TKA. The HA cohort had a total population of 164,000, of which 13,044 (8.0%) received a subsequent TKA. Due to the low population within the PRP group, this group was excluded from comparison. The mean time to TKA from first injection in the HA group was 377.8 days, while in the corticosteroid group it was 370.0 days. The proportions of TKA-free survival for CS and HA when compared at 4 years post-injection was similar between groups (p = 0.05). Discussion and Conclusion: Patients that received only IA-corticosteroids or IA-hyaluronic acid had a similar length of time between the first injection and the total knee arthroplasty associated with the injected joint. This evidence provides information for clinicians and patients alike when contemplating these non-surgical injection modalities for KOA. The similarity observed between these treatments supports the need for future research to determine whether there is any potential for reduction in healthcare costs for KOA treatment prior to TKA.

Advancements in Periodontal Regeneration: A Comprehensive Review of Stem Cell Therapy

Periodontal disease, characterized by inflammation and infection of the supporting structures of teeth, presents a significant challenge in dentistry and public health. Current treatment modalities, while effective to some extent, have limitations in achieving comprehensive periodontal tissue regeneration. This comprehensive review explores the potential of stem cell therapy in advancing the field of periodontal regeneration. Stem cells, including mesenchymal stem cells (MSCs) and induced pluripotent stem cells (iPSCs), hold promise due to their immunomodulatory effects, differentiation potential into periodontal tissues, and paracrine actions. Preclinical studies using various animal models have revealed encouraging outcomes, though standardization and long-term assessment remain challenges. Clinical trials and case studies demonstrate the safety and efficacy of stem cell therapy in real-world applications, especially in personalized regenerative medicine. Patient selection criteria, ethical considerations, and standardized treatment protocols are vital for successful clinical implementation. Stem cell therapy is poised to revolutionize periodontal regeneration, offering more effective, patient-tailored treatments while addressing the systemic health implications of periodontal disease. This transformative approach holds the potential to significantly impact clinical practice and improve the overall well-being of individuals affected by this prevalent oral health concern. Responsible regulatory compliance and a focus on ethical considerations will be essential as stem cell therapy evolves in periodontal regeneration.

Stem-cell clinics in the UK: a web-based study

Aim: Explore the nature and extent of web-based promotion of stem cell treatments marketed by clinics in the UK. Materials & methods: Web-based analysis of clinics in the UK using predefined variables, with analysis of eligible clinics according to preset criteria of ethical relevance. Results: A majority (79%) of UK clinics were judged to be problematic. Information was found to be lacking, misleading or otherwise problematic in several respects, including a lack of information on risks of adverse effects, unjustifiably optimistic depictions of therapeutic effectiveness, and questionable presentational approaches such as the use of celebrity patient testimonials. Conclusion: In a majority of cases, commercial clinics in the UK portray stem-cell therapies on their websites in ethically questionable ways.

Patient Age and Cell Concentration Influence Prevalence and Concentration of Progenitors in Bone Marrow Aspirates: An Analysis of 436 Patients

BACKGROUND

Connective tissue progenitors (CTPs) resident in native tissues serve as biological building blocks in tissue repair and remodeling processes. Methods for analysis and reporting on CTP quantity and quality are essential for defining optimal cell sources and donor characteristics and the impact of cell processing methods for cell therapy applications. The present study examines the influence of donor characteristics and cell concentration (nucleated cells/mL) on CTP prevalence (CTPs/million nucleated cells) and CTP concentration (CTPs/mL) in bone marrow aspirates (BMAs).

METHODS

Iliac crest bone marrow was aspirated from 436 patients during elective total knee or hip arthroplasty. Bone marrow-derived nucleated cells were plated at a density of 1.19 × 105 cells/cm2. Colony-forming unit analysis was performed on day 6.

RESULTS

Large variation was seen between donors. Age (p < 0.05) and cell concentration (p < 0.001) significantly influenced CTP prevalence and CTP concentration. For every 1-year increase in age, the odds of having at least an average CTP prevalence and CTP concentration decreased by 1.5% and 1.6%, respectively. For every 1 million cells/mL increase in cell concentration, the odds of having at least an average CTP prevalence and CTP concentration increased by 2.2% and 7.9%, respectively. Sex, race, body mass index (BMI), and the presence of osteoporosis did not influence CTP prevalence or CTP concentration.

CONCLUSIONS

BMA-derived CTPs were obtained from all patient groups. CTP prevalence and CTP concentration decreased with age. Cell concentration decreased with age and positively correlated with total CTP prevalence and CTP concentration. The mean CTP concentration in patients >60 years of age was a third of the CTP concentration in patients <30 years of age.

CLINICAL RELEVANCE

Proper BMA techniques are necessary to obtain a high-quality yield and composition of cells and CTPs. The reduced CTP concentration and CTP prevalence in the elderly may be mitigated by the use of cell processing methods that increase CTP concentration and CTP prevalence (e.g., by removing red blood cells, serum, and non-CTPs or by increasing aspirate volumes). Cell concentration in the BMA can be measured at the point of care and is an appropriate initial assessment of the quality of BMA.

Safety of intraarticular corticosteroid injection preceding hip and knee arthroplasty: a systematic review and meta-analysis amid resolving COVID-19 arthroplasty restrictions

Intraarticular corticosteroid injection (ICSI) is a widely practiced management for hip and knee osteoarthritis. Imposed delays to arthroplasty during coronavirus disease 2019 pandemic have led us to postulate that many patients have opted for recent ICSI. We compared the odds of prosthetic joint infection (PJI) in patients who were or were not administered ICSI within 12 months prior to hip or knee arthroplasty. A systematic search of PubMed, Embase, The Cochrane Library and Web of Science was performed in February 2021, with studies assessing the effect of ICS on PJI rates identified. All studies, which included patients that received ICSI in the 12 months prior to primary hip and knee arthroplasty, were included. In total 12 studies were included: four studies with 209 353 hips and eight studies with 438 440 knees. ICSI administered in the 12 months prior to hip arthroplasty increased the odds of PJI [odds ratio (OR) = 1.17, P = 0.04]. This was not the case for knees. Subgroup analysis showed significantly higher odds of PJI in both hip [OR = 1.45, P = 0.002] and knee arthroplasty [OR = 2.04; P = 0.04] when ICSI was within the preceding 3 months of surgery. A significantly higher odds of PJI were seen in patients receiving ICSI within the 12 months prior to hip arthroplasty. Subgroup analysis showed increased odds of PJI in both hip and knee arthroplasty, in patients receiving ICSI within 3 months prior to their arthroplasty. We recommend delaying knee arthroplasty for at least 3 months after ICSI and possibly longer for hip arthroplasty.

Editorial Commentary: Stem Cells. They Are in the Fat Tissue, Bone Marrow, and Even in the Synovial Fluid of the Knee Joint

Adult stem cells have been isolated in bone marrow and adipose tissue. These mesenchymal stromal cells (MSCs) have the ability to differentiate into osteogenic, chondrogenic, and adipogenic cell lines. The study by Branch et al. has identified MSCs in the synovial fluid of the knee in patients after anterior cruciate ligament injury and in patients with osteoarthritis of the knee. When mixing synovial fluid with whole blood and using a commercially available platelet-rich plasma-processing system, the total number of MSCs doubled in both groups when compared with the cell count in synovial fluid only. However, it is not clear whether the MSCs in the processed synovium-whole blood mix include synovial MSCs versus MSCs from only the blood. In addition, cell counts were substantially lower when compared with the typical concentrations of MSCs in bone marrow aspirate. The clinical application is yet to be defined.