Regenerative Medicine For Treatment Research Articles

Revolutionizing medicine: Molecularly imprinted polymers as precision tools in cancer diagnosis and antibiotic detection.

Molecularly imprinted polymers (MIPs) are pivotal in medicine, mimicking biological receptors with enhanced specificity and affinity. Comprising templates, functional monomers, and cross-linkers, MIPs form stable three-dimensional polymer networks. Synthetic templates like glycan and aptamers improve efficiency, guiding the molecular imprinting process. Cross-linking determines MIPs' morphology and mechanical stability, with printable hydrogels offering biocompatibility and customizable properties, mimicking native extracellular matrix (ECM) microenvironments. Their versatility finds applications in tissue engineering, soft robotics, regenerative medicine, and wastewater treatment. In cancer research, MIPs excel in both detection and therapy. MIP-based detection systems exhibit superior sensitivity and selectivity for cancer biomarkers. They target nucleic acids, proteins, and exosomes, providing stability, sensitivity, and adaptability. In therapy, MIPs offer solutions to challenges like multidrug resistance, excelling in drug delivery, photodynamic therapy, photothermal therapy, and biological activity regulation. In microbiology, MIPs serve as adsorbents in solid-phase extraction (SPE), efficiently separating and enriching antibiotics during sample preparation. They contribute to bacterial identification, selectively capturing specific strains or species. MIPs aid in detecting antibiotic residues using fluorescent nanostructures and developing sensors for sulfadiazine detection in food samples. In summary, MIPs play a pivotal role in advancing medical technologies with enhanced sensitivity, selectivity, and versatility. Applications range from biomarker detection to innovative cancer therapies, making MIPs indispensable for the accurate determination and monitoring of diverse biological and environmental samples.

Direct reprogramming of fibroblasts into functional hepatocytes via CRISPRa activation of endogenous Gata4 and Foxa3.

The ability to generate functional hepatocytes without relying on donor liver organs holds significant therapeutic promise in the fields of regenerative medicine and potential liver disease treatments. Clustered regularly interspaced short palindromic repeats (CRISPR) activator (CRISPRa) is a powerful tool that can conveniently and efficiently activate the expression of multiple endogenous genes simultaneously, providing a new strategy for cell fate determination. The main purpose of this study is to explore the feasibility of applying CRISPRa for hepatocyte reprogramming and its application in the treatment of mouse liver fibrosis. The differentiation of mouse embryonic fibroblasts (MEFs) into functional induced hepatocyte-like cells (iHeps) was achieved by utilizing the CRISPRa synergistic activation mediator (SAM) system, which drove the combined expression of three endogenous transcription factors- Gata4, Foxa3 , and Hnf1a -or alternatively, the expression of two transcription factors, Gata4 and Foxa3 . In vivo , we injected adeno-associated virus serotype 6 (AAV6) carrying the CRISPRa SAM system into liver fibrotic Col1a1-CreER ; Cas9fl/fl mice, effectively activating the expression of endogenous Gata4 and Foxa3 in fibroblasts. The endogenous transcriptional activation of genes was confirmed using real-time quantitative polymerase chain reaction (RT-qPCR) and RNA-seq, and the morphology and characteristics of the induced hepatocytes were observed through microscopy. The level of hepatocyte reprogramming in vivo is detected by immunofluorescence staining, while the improvement of liver fibrosis is evaluated through Sirius red staining, alpha-smooth muscle actin (α-SMA) immunofluorescence staining, and blood alanine aminotransferase (ALT) examination. Activation of only two factors, Gata4 and Foxa3 , via CRISPRa was sufficient to successfully induce the transformation of MEFs into iHeps. These iHeps could be expanded in vitro and displayed functional characteristics similar to those of mature hepatocytes, such as drug metabolism and glycogen storage. Additionally, AAV6-based delivery of the CRISPRa SAM system effectively induced the hepatic reprogramming from fibroblasts in mice with live fibrosis. After 8 weeks of induction, the reprogrammed hepatocytes comprised 0.87% of the total hepatocyte population in the mice, significantly reducing liver fibrosis. CRISPRa-induced hepatocyte reprogramming may be a promising strategy for generating functional hepatocytes and treating liver fibrosis caused by hepatic diseases.

Recent trends of stem cell therapies in The management of orthopedic surgical challenges.

Emerged health-related problems especially with increasing population and with the wider occurrence of these issues have always put the utmost concern and led medicine to outgrow its usual mode of treatment, to achieve better outcomes. Orthopedic interventions are one of the most concerning hitches, requiring advancement in several issues, that show complications with conventional approaches. Advanced studies have been undertaken to address the issue, among which stem cell therapy emerged as a better area of growth. The capacity of the stem cells to renovate themselves and adapt into different cell types made it possible to implement its use as a regenerative slant. Harvesting the stem cells, particularly mesenchymal stem cells is easier and can be further grown in vitro. In this review, we have discussed orthopedic-related issues including bone defects and fractures, non-unions, ligament and tendon injuries, degenerative changes, and associated conditions, which require further approaches to execute better outcomes, and the advanced strategies that can be tagged along with various ways of application of mesenchymal stem cells. It aims to objectify the idea of stem cells, with a major focus on the application of Mesenchymal stem cells (MSCs) from different sources in various orthopedic interventions. It also discusses the limitations, and future scopes for further approaches in the field of regenerative medicine. The involvement of mesenchymal stem cells may transition the procedures in orthopedic interventions from predominantly surgical substitution and reconstruction to bio-regeneration and prevention. Nevertheless, additional improvements and evaluations are required to explore the effectiveness and safety of mesenchymal stem cell treatment in orthopedic regenerative medicine.

Three-Dimensional Bioprinting: The Ultimate Pinnacle of Tissue Engineering.

Three-dimensional (3D) bioprinting has emerged as a revolutionary additive manufacturing technology that can potentially enable life-changing medical treatments in regenerative medicine. It applies the principles of tissue engineering for the printing of tissues and organs in a layer-by-layer manner. This review focuses on the various 3D bioprinting technologies currently available, the different biomaterials, cells, and growth factors that can be utilized to develop tissue-specific bioinks, the different venues for applying these technologies, and the challenges this technology faces.

Regenerative Medicine Solutions for Rotator Cuff Injuries in Athletes: Indications and Outcomes.

Rotator cuff (RC) injuries include a wide range of pathologic states. Athletes are perhaps the most susceptible to RC injuries ranging from tendinopathy to partial or full-thickness tears, due to functional overload and repetitive movements, causing abstention from sports for long periods. Regenerative medicine keeps giving us multiple choices to fight the disability caused by these pathologies. A literature search was performed, and findings related to the structure-function of rotator cuff units, pathophysiology of injuries, regenerative medicine treatments, and future strategies were outlined. Platelet-rich plasma (PRP) has a greater number of articles and clinical trials, accompanied by stem cells progenitor, prolotherapy, and new approaches such as microfragmented adipose tissue and exosomes. RC injuries in athletes can cause pain, functional impotence, and the risk of recurrence, and can lead them to stop playing sports. Regenerative medicine offers a range of treatments, but some of them need further studies to underline their actual validity.

Usefulness of platelet-rich fibrin as a scaffold for meniscal repair: A non-randomized controlled cohort/follow-up study

BackgroundAlthough regenerative medicine treatment is still in its infancy in Japan, legislation within the past decade has provided opportunities to explore new treatment methods using regenerative medicine. We conducted a 2-year prospective follow-up study to statistically analyze treatment outcomes using platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) as effective scaffolds in meniscal repair.Questions/Purposes.1. Does the use of PRF and PRP for meniscal repair surgery regenerate the meniscus?2. Does augmentation of meniscal repair with PRF effectively improve knee function outcomes? MethodsThirty-five patients underwent arthroscopic meniscal repair with PRP and PRF using new devices with all-inside techniques. Among these, 31 patients were evaluated for clinical outcomes postoperatively, and magnetic resonance imaging (MRI) findings were evaluated. The variables were coded appropriately by creating a new column based on the Kellgren–Lawrence classification over time. Log transformation of different time points (pre, post 6, 12, or 24 months) in relation to Lysholm, International Knee Documentation Committee (IKDC), Japanese Orthopedic Association (JOA), and Tegner scores were performed. Follow-up arthroscopy using a needle scope was performed in some cases 2 years later. The PRP and PRF used were characterized using the Minimum Information for Studies Evaluating Biologics in Orthopaedics classification. ResultsOverall, 31 patients were evaluated (mean age = 39.1 ± 15.7 years; preoperative rehabilitation period = 9.5 ± 7.7 weeks). The PRP had mean platelet and white blood cell concentrations of approximately 5.5- and 3.6-fold, respectively. A significant association existed between sex and deformity deterioration but not in age between the two groups classified by deformity deterioration. Surgical intervention significantly and positively impacted knee function, although no significant changes were found in the activity of the participants over time. MRI findings showed no regeneration of the repaired meniscus; nevertheless, none of them worsened. Furthermore, a case where the traumatic cartilage defect was covered with fibrocartilage-like tissue as a secondary finding was observed. ConclusionsMeniscal repair surgery using PRP/PRF is an effective treatment option for improving knee function in patients with knee deformity. Level of evidenceLevel III, Non-randomized controlled cohort/follow-up study.

Selecting Monoclonal Cell Lineages from Somatic Reprogramming Using Robotic-Based Spatial-Restricting Structured Flow.

Somatic cell reprogramming generates induced pluripotent stem cells (iPSCs), which serve as a crucial source of seed cells for personalized disease modeling and treatment in regenerative medicine. However, the process of reprogramming often causes substantial lineage manipulations, thereby increasing cellular heterogeneity. As a consequence, the process of harvesting monoclonal iPSCs is labor-intensive and leads to decreased reproducibility. Here, we report the first in-house developed robotic platform that uses a pin-tip-based micro-structure to manipulate radial shear flow for automated monoclonal iPSC colony selection (~1 s) in a non-invasive and label-free manner, which includes tasks for somatic cell reprogramming culturing, medium changes; time-lapse-based high-content imaging; and iPSCs monoclonal colony detection, selection, and expansion. Throughput-wise, this automated robotic system can perform approximately 24 somatic cell reprogramming tasks within 50 days in parallel via a scheduling program. Moreover, thanks to a dual flow-based iPSC selection process, the purity of iPSCs was enhanced, while simultaneously eliminating the need for single-cell subcloning. These iPSCs generated via the dual processing robotic approach demonstrated a purity 3.7 times greater than that of the conventional manual methods. In addition, the automatically produced human iPSCs exhibited typical pluripotent transcriptional profiles, differentiation potential, and karyotypes. In conclusion, this robotic method could offer a promising solution for the automated isolation or purification of lineage-specific cells derived from iPSCs, thereby accelerating the development of personalized medicines.

Carbon nanotube nanocomposite scaffolds: advances in fabrication and applications for tissue regeneration and cancer therapy.

Carbon nanotube (CNT) nanocomposite scaffolds have emerged as highly promising frameworks for tissue engineering research. By leveraging their intrinsic electrical conductivity and valuable mechanical properties, CNTs are commonly dispersed into polymers to create robust, electrically conductive scaffolds that facilitate tissue regeneration and remodeling. This article explores the latest progress and challenges related to CNT dispersion, functionalization, and scaffold printing techniques, including electrospinning and 3D printing. Notably, these CNT scaffolds have demonstrated remarkable positive effects across various cell culture systems, stimulating neuronal growth, promoting cardiomyocyte maturation, and facilitating osteocyte differentiation. These encouraging results have sparked significant interest within the regenerative medicine field, including neural, cardiac, muscle, and bone regenerations. However, addressing the concern of CNT cytotoxicity in these scaffolds remains critical. Consequently, substantial efforts are focused on exploring strategies to minimize cytotoxicity associated with CNT-based scaffolds. Moreover, researchers have also explored the intriguing possibility of utilizing the natural cytotoxic properties of CNTs to selectively target cancer cells, opening up promising avenues for cancer therapy. More research should be conducted on cutting-edge applications of CNT-based scaffolds through phototherapy and electrothermal ablation. Unlike drug delivery systems, these novel methodologies can combine 3D additive manufacturing with the innate physical properties of CNT in response to electromagnetic stimuli to efficiently target localized tumors. Taken together, the unique properties of CNT-based nanocomposite scaffolds position them as promising candidates for revolutionary breakthroughs in both regenerative medicine and cancer treatment. Continued research and innovation in this area hold significant promise for improving healthcare outcomes.

A systematic review of the efficacy, safety and satisfaction of regenerative medicine treatments, including platelet-rich plasma, stromal vascular fraction and stem cell-conditioned medium for hypertrophic scars and keloids.

The primary objective of this study is to examine the efficiency of various regenerative medicine approaches, such as platelet-rich plasma, cell therapy, stromal vascular fraction, exosomes and stem cell-conditioned medium, in the process of healing hypertrophic and keloid scars. Major databases including PubMed, Scopus and Web of Science were systematically searched, and based on the content of the articles and the inclusion and exclusion criteria, eight articles were selected. Out of these eight articles, there were two non-randomized clinical trial studies (25%), one randomized, single-blinded comparative study (12.5%), one retrospective clinical observational study (12.5%) and four randomized clinical trial studies (50%). We employed EndNote X8 and Google Sheets to conduct article reviews and extract relevant data. Following the review phase, the studies underwent analysis and categorization. In all eight reviewed studies, the effectiveness of regenerative medicine in treating hypertrophic scars and keloids has been proven. Out of these studies, five (62.5%) focused on the effectiveness of platelet-rich plasma, two study (25%) examined the effectiveness of stromal vascular fraction and one study (12.5%) explored the efficacy of stem cell-conditioned medium. In two studies (25%), the treatment methods were added to standard treatment, while in six studies (75%), regenerative medicine was used as the sole treatment method and compared with standard treatment. The use of these treatment methods did not result in any serious side effects for the patients. Regenerative medicine is an effective method with minimal side effects for the treatment of hypertrophic scars and keloids. It can be used as a monotherapy or in combination with other treatment methods. However, further studies are needed to thoroughly evaluate the effectiveness of all sub-branches of this method.

Current Review of Regenerative Medicine Therapies for Spine-Related Pain.

Persistent spinal pain syndromes are pervasive and lead to functional impairment, increased healthcare utilization, potential disability, and high societal costs. Spinal (cervical, thoracic, lumbar, and sacroiliac joint) pain includes mechanical, degenerative, inflammatory, oncologic, and infectious etiologies. Regenerative medicine is a novel biotechnology targeting mechanical, degenerative, and inflammatory conditions believed to cause pain. Preparations including platelet-rich plasma, mesenchymal stem cells (adipose tissue and bone marrow aspirate concentrates), and growth factors are derived from an autologous donor. The goal of intervention through guided injection of the regenerative media is to reduce inflammation and reverse the degenerative cascade in hopes of restoring normal cellular composition (physiologic homeostasis) and anatomical function to improve pain and function. The authors review limited research supporting the use of platelet-rich plasma injections for facet joint arthropathy and sacroiliac joint pain compared to traditional steroid treatments, as well as the use of platelet rich plasma or mesenchymal stem cells for lumbar discogenic and radicular pain. Current evidence to support regenerative medicine for spine-related pain is limited. Although several studies demonstrated a reduction in pain, many of these studies had a small number of participants and were case series or prospective trials. Regenerative medicine treatments lack evidence for the treatment of spine-related pain. Large randomized controlled trials are needed with consistent study protocols to make further recommendations.

New Insights into Hematopoietic Redefinition and New Paradigms in Hematopoietic Hierarchy Roadmap

The definition of hematopoietic progenitor cells (HPCs) has not been standardized. Surface markers are insufficient to capture the entire differentiation stages of progenitor cells and reflect the dynamic differentiation mechanisms underlying hematopoiesis. Deciphering the hematopoiesis mechanism that underlies progenitor cells definition and fate decision are critical to understanding fundamental questions of hematopoietic lineage commitment. Here, we redefined the entire spectrum of adult hematopoietic progenitors, and recovered the critical transcript factors (TFs) in lineages fate decision, and reaffirmed the lineage commitment model of HPCs by a comprehensive transcriptome. The progenitor lineages were accurately redefined with unique makers and transcription factors by unsupervised dimensionality reduction and clustering, which subverted the conventional definition of HPCs（Table 1）. The expression characteristics of TFs, such as GATA1, KLF1, PRDM1, and MAFB, presented enormous capacity to define the entire spectrum of HPCs. The transcriptional atlas showed that original hematopoietic progenitors were simultaneously primed into lymphoid, neutrophils, and megakaryocytic-erythroid progenitor cell types in the initial differentiation stage and thereafter matured into different hematopoietic lineages (Figure 1). The common intermediate progenitor stage was not observed among myeloid lineages, indicating the absence of a common myeloid progenitor during the lineage commitment. Our transcriptional atlas revealed the major fate decision factors in each branch among hematopoietic hierarchy formation (Table 1). Several fate decision factors were identified, including GATA2, TESPA1, and MYB of myeloid progenitors and HOXA9, HOPX, and TSC22D1 of lymphoid progenitors. Through the sequential activation/deactivation of TFs, synergism with key receptor genes, and signal activation, the original progenitor cells were primed and differentiated into various progenitors. The expression and activation characteristics of fate decision TFs faithfully reflect the mechanisms underlying hematopoietic lineage commitment. A hematopoietic hierarchy roadmap was reaffirmed. Our reaffirmed hematopoietic hierarchy validated that the megakaryocytic-erythroid lineage process is continuous, while the lymphoid lineage process is more likely a discrete stepwise progression with distinct lineage-committed populations during hematopoiesis, opening a new perspective on hematopoiesis (Figure 1). Our study revealed that the original progenitors of basophils, eosinophils, and neutrophils differed. Plasma progenitor cells were first identified and defined, and the rearrangements of IGHV, IGKV, and IGLV genes were already existed and occurred during the progenitor state of plasma cells. In summary, our transcriptional atlas of HPCs provides an accurate definition, hierarchy, and biological insights into hematopoiesis and lineage commitment. Our study opens up numerous possibilities for precise and controlled progenitor cell differentiation, facilitating research development in regenerative medicine and disease treatment.

Local application of engineered insulin-like growth factor I mRNA demonstrates regenerative therapeutic potential in vivo

Insulin-like growth factor I (IGF-I) is a growth-promoting anabolic hormone that fosters cell growth and tissue homeostasis. IGF-I deficiency is associated with several diseases, including growth disorders and neurological and musculoskeletal diseases due to impaired regeneration. Despite the vast regenerative potential of IGF-I, its unfavorable pharmacokinetic profile has prevented it from being used therapeutically. In this study, we resolved these challenges by the local administration of IGF-I mRNA, which ensures desirable homeostatic kinetics and non-systemic, local dose-dependent expression of IGF-I protein. Furthermore, IGF-I mRNA constructs were sequence engineered with heterologous signal peptides, which improved invitro protein secretion (2- to 6-fold) and accelerated invivo functional regeneration (16-fold) over endogenous IGF-I mRNA. The regenerative potential of engineered IGF-I mRNA was validated in a mouse myotoxic muscle injury and rabbit spinal disc herniation models. Engineered IGF-I mRNA had a half-life of 17-25h in muscle tissue and showed dose-dependent expression of IGF-I over 2-3days. Animal models confirm that locally administered IGF-I mRNA remained at the site of injection, contributing to the safety profile of mRNA-based treatment in regenerative medicine. In summary, we demonstrate that engineered IGF-I mRNA holds therapeutic potential with high clinical translatability in different diseases.

Activation of cell adhesion and migration is an early event of platelet-rich plasma (PRP)-dependent stimulation of human adipose-derived stem/stromal cells.

Stem cell therapy is a promising treatment in regenerative medicine. Human adipose-derived stem/stromal cells (hASCs), a type of mesenchymal stem cell, are easy to harvest. In plastic and aesthetic surgery, hASC may be applied in the treatment of fat grafting, wound healing, and scar remodeling. Platelet-rich plasma (PRP) contains various growth factors, including platelet-derived growth factor (PDGF), which accelerates wound healing. We previously reported that PRP promotes the proliferation of hASC via multiple signaling pathways, and we evaluated the effect of PRP on the stimulation of hASC adhesion and migration, leading to the proliferation of these cells. When hASCs were treated with PRP, AKT, ERK1/2, paxillin and RhoA were rapidly activated. PRP treatment led to the formation of F-actin stress fibers. Strong signals for integrin β1, paxillin and RhoA at the cell periphery of RPR-treated cells indicated focal adhesion. PRP promoted cell adhesion and movement of hASC, compared with the control group. Imatinib, an inhibitor of the PDGF receptor tyrosine kinase, inhibited the promotion of PRP-dependent cell migration. PDGF treatment of hASCs also stimulated cell adhesion and migration but to a lesser extent than PRP treatment. PRP promoted the adhesion and the migration of hASC, mediated by the activation of AKT in the integrin signaling pathway. PRP treatment was more effective than PDGF treatment in enhancing cell migration. Thus, the ability of PRPs to promote migration of hASC to enhance cell growth is evident.

Study of anti-inflammatory and immunomodulatory potential of endometrial mesenchymal stem cells-derived exosomes with micro-ultrasound (μUS) guidance in regeneration β-islets on T1D animal model

Type 1 diabetes results from the inflammatory destruction of beta cells, leading to severe insulin deficiency. MSCs have an effective role in modulating immune and inflammatory reactions and are known as a standard platform for the treatment in regenerative medicine. Despite evidence of MScs’ effectiveness in diseases, they still are associated with safety challenges. Exosomes are natural nanoparticles secreted into the extracellular space by most cells. After the isolation and characterization of human Endometrial MSC-derived exosomes (hEnEx), diabetes model was induced by destroying islets using intraperitoneal injection of streptozotocin (STZ) in male rats. The characterized EnEx and EnMSCs were injected into pancreatic areas in diabetic animals under guidance of the micro-ultrasound non-invasive method. In the current study, the animals' blood glucose levels and body weight were monitored, accompanied by increased body weight and decreased blood sugar in the treated groups. Our findings indicate specific therapeutic effects of EnEx in β-islets neogenesis, normal islets formation, and insulin secretion. Evidence that shows functional role of EnEx in regulation of inflammatory and immune responses in EnEx-treated rats. Evaluation of insulin and pdx1 proteins expression showed presence of insulin and also EnEx antidiabetics effects in β-cells through the pdx1 pathway. This study determined that exosome therapy is more effective compared to cell therapy in improving diabetes, especially regeneration of β-islets mass. Also, exosome injection with the micro-ultrasound method has more efficacy in restoring β‐cell function. Therefore, EnEx based-treatment can be a novel therapeutic agent with minimal or no unwanted side effects for diabetic patients.

Adipose-Derived Stem Cell Injection on a Grade III Medial Collateral Ligament Tear in a Soccer Player: A Case Report

Stem cells are undifferentiated cells that can divide and differentiate into various types of cells. This special ability makes stem cells a hopeful treatment for regenerating damaged tissue and restoring diminished or completely lost function. In this case study, we discuss a 19-year-old soccer player who presented with a Grade III MCL tear on the right knee. Treatment for a Grade III MCL tear is controversial being that both surgical and non-surgical approaches have been effective. However, due to the patient’s sports background, the patient came to our clinic seeking a faster recovery using a non-surgical treatment. After extensive medical examinations, the patient began a treatment based on adipose tissue-derived stem cells injection. Adipose tissue-derived stem cells were harvested and injected into the distal insertion of the superficial MCL and on the deep MCL origin. After 122 days the patient was able to practice full contact sports which is a significant decrease compared to a recent study that averaged surgical recovery time to 181 days. The recovery was supported by an MRI which demonstrated full regeneration of the previously damaged MCL. This case study demonstrates the potential stem cells have in both complementing and replacing surgical treatments for tissue repair. In addition, this case study demonstrates the efficacy of accelerating recovery of MCL tears using stem cells which inspires hope of using stem cells in similar pathologies. Therefore, more clinical trials should be conducted to further expand research on stem cell treatment in regenerative medicine.

Self-Assembled Peptide Hydrogels in Regenerative Medicine.

Regenerative medicine is a complex discipline that is becoming a hot research topic. Skin, bone, and nerve regeneration dominate current treatments in regenerative medicine. A new type of drug is urgently needed for their treatment due to their high vulnerability to damage and weak self-repairing ability. A self-assembled peptide hydrogel is a good scaffolding material in regenerative medicine because it is similar to the cytoplasmic matrix environment; it promotes cell adhesion, migration, proliferation, and division; and its degradation products are natural and harmless proteins. However, fewer studies have examined the specific mechanisms of self-assembled peptide hydrogels in promoting tissue regeneration. This review summarizes the applications and mechanisms of self-assembled short peptide and peptide hydrogels in skin, bone, and neural healing to improve their applications in tissue healing and regeneration.

Stem Cell Therapy for Aging Related Diseases and Joint Diseases in Companion Animals.

Stem cell therapy is an attractive treatment for diseases in companion animals that cannot be treated by conventional veterinary medicine practices. The unique properties of stem cells, particularly the ability to differentiate into specific cell types, makes them a focal point in regenerative medicine treatments. Stem cell transplantation, especially using mesenchymal stem cells, has been proposed as a means to treat a wide range of injuries and ailments, resulting in tissue regeneration or repair. This review aims to summarize the veterinary use of stem cells for treating age-related and joint diseases, which are common conditions in pets. While additional research is necessary and certain limitations exist, the potential of stem cell therapy for companion animals is immense.

The Assessment of Dietary interventions on Stem Cell Fate, Homeostatic Mechanisms, and Disease

Economic growth and globalisation have increased food availability and disposable income, causing people to rely on nutrient-poor fast foods due to their low price and wide availability instead of nutritious produce. Global statistics show the population consumes exponentially more fats and carbohydrates than proteins, vegetables, and fruits. This dietary pattern negatively impacts public health, increasing prevalence of obesity and diet related diseases like diabetes, heart disease, and hypertension. When used appropriately, dietary interventions have a profound effect on stem cell regeneration and homeostasis, hormone signaling, and prevalence of disease and obesity, posing strong potential in regenerative medicine and non-communicable disease treatment. This review studies caloric restriction, prolonged fasting, the ketogenic diet, and the high fat diet and outlines their effect on stem cell fate and numbers, hormone and metabolism levels, and prevalence of disease and discusses the advantages, disadvantages, and future directions of each dietary intervention.

Potency Assays for Mesenchymal Stromal Cell Secretome-Based Products for Tissue Regeneration.

Adult stem cells maintaining tissue homeostasis and regeneration are tightly regulated by their specific microenvironments or stem cell niches. The dysfunction of niche components may alter the activity of stem cells and ultimately lead to intractable chronic or acute disorders. To overcome this dysfunction, niche-targeting regenerative medicine treatments such as gene, cell, and tissue therapy are actively investigated. Here, multipotent mesenchymal stromal cells (MSCs), and particularly their secretomes, are of high interest due to their potency to recover and reactivate damaged or lost stem cell niches. However, a workflow for the development of MSC secretome-based products is not fully covered by regulatory authorities, and and this issue significantly complicates their clinical translation and has possibly been expressed in a huge number of failed clinical trials. One of the most critical issues in this regard relates to the development of potency assays. In this review, guidelines for biologicals and cell therapies are considered to be applied for the development of potency assays for the MSC secretome-based products that aim for tissue regeneration. Specific attention is paid to their possible effects on stem cell niches and to a spermatogonial stem cell niche in particular.

Pd@Pt nanoparticle-linked immunosorbent assay for quantification of Collagen type II

The evaluation of specific protein content in engineered tissues provides a gateway for developing regenerative medicine treatments. Since collagen type II, the major component of articular cartilage, is critical for the blossoming field of articular cartilage tissue engineering, the interest in this protein is growing rapidly. Accordingly, the need for quantification of collagen type II is increasing as well. In this study, we provide recent results for a new quantifying nanoparticle sandwich immunoassay technique for collagen type II. Since mesoporous palladium@platinum (Pd@Pt) nanoparticles have peroxidase-like catalytic activities, these nanoparticles were utilized in an enzyme-linked immunosorbent assay (ELISA)-like format to circumvent the need for traditional enzymes. These nanoparticles were easily conjugated with anti-collagen type II antibodies by the natural affinity interaction and used to develop a direct sandwich ELISA-like format for nanoparticle-linked immunosorbent assays. Using this method, we obtained a limit of detection of 1 ng mL−1, a limit of quantification of 9 ng mL-1. and a broad linear range between 1 ng mL−1 and 50 μg mL−1 for collagen type II with an average relative standard deviation of 5.5%, useable over a pH range of 7 – 9 at least. The assay was successfully applied to quantify collagen type II in cartilage tissues and compared with the results of commercial ELISAs and gene expression by reverse transcription-quantitative polymerase chain reaction. This method provides a thermally stable and cost-efficient alternative to traditional ELISAs. It also extends the application of nanoparticle-linked immunosorbent assays, thereby providing the potential to quantify other proteins and apply the technology in the medical, environmental, and biotechnology industry fields.