Isolation and characterization of canine umbilical cord blood-derived mesenchymal stem cells

Characterization of Canine Gingival-Derived Mesenchymal Stem Cells and Their Exosomes

Mesenchymal stem cells (MSCs) can be isolated from numerous tissues and have the potential for self-renewal and multidirectional differentiation. Evidence is accumulating which suggests that MSCs are also present in the gingival tissue. This study aimed to evaluate the feasibility of collecting, purifying, and amplifying gingival-derived MSCs (GMSCs) from canine gingiva and to obtain GMSC-derived exosomes (GMSC-exo). GMSCs were isolated and cultured; furthermore, cellular immunofluorescence demonstrated that GMSCs possess characteristic MSC markers, and in vitro differentiation was induced, indicating that GMSCs can differentiate into multiple lineages. GMSC-exo was successfully extracted from GMSCs supernatant and found that they exhibit the typical characteristics of exosomes as analyzed by transmission electron microscopy, nanoflow analysis, and western blotting. GMSC-exo promoted the proliferation and migration of Madin-Darby canine kidney cells. It was concluded that canine gingiva is a good source of MSCs. Additionally, GMSC-exo is a potentially promising cell-free therapeutic tool for the treatment of canine gingival diseases.

Immunomodulatory effects of canine mesenchymal stem cells in an experimental atopic dermatitis model

Mesenchymal stem cells (MSCs) have the potential to differentiate into multi-lineage cells, suggesting their future applicability in regenerative medicine and biotechnology. The immunomodulatory properties of MSCs make them a promising replacement therapy in various fields of animal research including in canine atopic dermatitis (AD), a skin disease with 10-15% prevalence. We investigated the immunomodulatory effects of MSCs in an experimental canine AD model induced by Dermatophagoides farinae extract ointment. Canine adipose tissue-derived MSCs (cAT-MSCs) were differentiated into mesodermal cell lineages at the third passage. Alterations in immunomodulatory factors in control, AD, and MSC-treated AD groups were evaluated using flow cytometric analysis, enzyme-linked immunosorbent assay, and quantitative reverse transcription PCR. In the MSC-treated AD group, the number of eosinophils decreased, and the number of regulatory T cells (Tregs) increased compared to those in the AD group. In addition, the immunoglobulin E (IgE) and prostaglandin E₂ levels were reduced in the MSC-treated AD group compared to those in the AD group. Furthermore, the filaggrin, vascular endothelial growth factor, and interleukin-5 gene expression levels were relatively higher in the MSC-treated AD group than in the AD group, however, not significantly. cAT-MSCs exerted immunomodulatory effects in an AD canine model via a rebalancing of type-1 and -2 T helper cells that correlated with increased levels of Tregs, IgE, and various cytokines.

Characterization of canine adipose- and endometrium-derived Mesenchymal Stem/Stromal Cells and response to lipopolysaccharide

Mesenchymal stem/stromal cells (MSCs) are used for regenerative therapy in companion animals. Their potential was initially attributed to multipotency, but subsequent studies in rodents, humans and veterinary species evidenced that MSCs produce factors that are key mediators of immune, anti-infective and angiogenic responses, which are essential in tissue repair. MSCs preparations have been classically obtained from bone marrow and adipose tissue (AT) in live animals, what requires the use of surgical procedures. In contrast, the uterus, which is naturally exposed to external insult and infection, can be accessed nonsurgically to obtain samples, or tissues can be taken after neutering. In this study, we explored the endometrium (EM) as an alternative source of MSCs, which we compared with AT obtained from canine paired samples. Canine AT- and EM-MSCs, formed CFUs when seeded at low density, underwent tri-lineage differentiation into adipocytes, osteocytes and chondrocytes, and expressed the CD markers CD73, CD90 and CD105, at equivalent levels. The immune genes IL8, CCL2 and CCL5 were equally expressed at basal levels by both cell types. However, in the presence of the inflammatory stimulus lipopolysaccharide (LPS), expression of IL8 was higher in EM- than in AT-MSCs (p < 0.04) while the other genes were equally elevated in both cell types (p < 0.03). This contrasted with the results for CD markers, where the expression was unaltered by exposing the MSCs to LPS. Overall, the results indicate that canine EM-MSCs could serve as an alternative cell source to AT-MSCs in therapeutic applications.

Manufacturing Mesenchymal Stromal Cells for the Treatment of Osteoarthritis in Canine Patients: Challenges and Recommendations

The recent interest in advanced biologic therapies in veterinary medicine has opened up opportunities for new treatment modalities with considerable clinical potential. Studies with mesenchymal stromal cells (MSCs) from animal species have focused on in vitro characterization (mostly following protocols developed for human application), experimental testing in controlled studies and clinical use in veterinary patients. The ability of MSCs to interact with the inflammatory environment through immunomodulatory and paracrine mechanisms makes them a good candidate for treatment of inflammatory musculoskeletal conditions in canine species. Analysis of existing data shows promising results in the treatment of canine hip dysplasia, osteoarthritis and rupture of the cranial cruciate ligament in both sport and companion animals. Despite the absence of clear regulatory frameworks for veterinary advanced therapy medicinal products, there has been an increase in the number of commercial cell-based products that are available for clinical applications, and currently the commercial use of veterinary MSC products has outpaced basic research on characterization of the cell product. In the absence of quality standards for MSCs for use in canine patients, their safety, clinical efficacy and production standards are uncertain, leading to a risk of poor product consistency. To deliver high-quality MSC products for veterinary use in the future, there are critical issues that need to be addressed. By translating standards and strategies applied in human MSC manufacturing to products for veterinary use, in a collaborative effort between stem cell scientists and veterinary researchers and surgeons, we hope to facilitate the development of quality standards. We point out critical issues that need to be addressed, including a much higher level of attention to cell characterization, manufacturing standards and release criteria. We provide a set of recommendations that will contribute to the standardization of cell manufacturing methods and better quality assurance.

Current Status on Canine Foetal Fluid and Adnexa Derived Mesenchymal Stem Cells

Effective standards of care treatment guidelines have been developed for many canine diseases. However, a subpopulation of patients is partially or completely refractory to these protocols, so their owners seek novel therapies such as treatments with MSCs. Although in dogs, as with human medicine, the most studied MSCs sources have been bone marrow and adipose tissue, in recent years, many researchers have drawn attention towards alternative sources, such as foetal adnexa and fluid, since they possess many advantages over bone marrow and adipose tissue. Foetal adnexa and fluid could be considered as discarded material; therefore, sampling is non-invasive, inexpensive and free from ethical considerations. Furthermore, MSCs derived from foetal adnexa and fluid preserve some of the characteristics of the primitive embryonic layers from which they originate and seem to present immune-modulatory properties that make them a good candidate for allo- and xenotransplantation. The aim of the present review is to offer an update on the state of the art on canine MSCs derived from foetal adnexa and fluid focusing on the findings in their clinical setting.

Stem cell therapy targets the neointimal smooth muscle cells in experimentally induced atherosclerosis: involvement of intracellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM)

Smooth muscle cells (SMCs) are currently considered a central pivotal player in pathogenesis and development of atherosclerotic lesions. As consequence of vascular injury, SMCs migrate from the tunica media into the tunica intima layers where they contribute to neointimal formation by converting into foam cells and producing pro-inflammatory and oxidative stress markers. We targeted the replacement of neointimal SMCs by using the mesenchymal stem cells (MSCs) therapy in experimentally induced atherosclerosis in an attempt to improve the atherosclerotic lesion and its concomitant complications. Rats were divided into 4 groups (n=20). Control group: rats kept on a standard chow diet; atherosclerotic group: rats received the atherogenic diet; stem cells-treated group: rats were injected with CD34+ stem cells (6×106 cells in 0.5 mL PBS in rat tail vein) and maintained on the atherogenic diet; and resveratrol-treated group: rats were supplemented orally with resveratrol at a dose level 3 mg/kg per day and the atherogenic diet. After 12 weeks, rats were euthanized, blood samples were collected for separation of serum, and abdominal aortas were excised for further biochemical, molecular, and histopathological investigations. We used resveratrol, the well-established anti-atherosclerotic drug, as a benchmark to assess the efficacy of stem cell therapy. MSCs treatment revealed significant amelioration in both histopathological and biochemical patterns as evidenced by decreased foam cells formation, ICAM-1, VCAM, M-CSF, iNOS, COX-2, and TNF-α. We concluded that MSCs therapy significantly replaced the neointimal SMCs and decreased adhesion molecules as well as the oxidative and inflammatory markers in atherosclerosis.

Biological characteristics and metabolic profile of canine mesenchymal stem cells isolated from adipose tissue and umbilical cord matrix

Despite the increasing demand of cellular therapies for dogs, little is known on the differences between adult and fetal adnexa canine mesenchymal stem cells (MSCs), and data on their metabolic features are lacking. The present study aimed at comparing the characteristics of canine adipose tissue (AT) and umbilical cord matrix (UC) MSCs. Moreover, for the first time in the dog, the cellular bioenergetics were investigated by evaluating the two main metabolic pathways (oxidative phosphorylation and glycolysis) of ATP production. Frozen-thawed samples were used for this study. No differences in mean cell proliferation were found (P>0.05). However, while AT-MSCs showed a progressive increase in doubling time over passages, UC-MSCs showed an initial post freezing-thawing latency. No differences in migration, spheroid formation ability, and differentiation potential were found (P>0.05). RT-PCR analysis confirmed the expression of CD90 and CD44, the lack of CD14 and weak expression of CD34, mostly by AT-MSCs. DLA-DRA1 and DLA-DQA1 were weakly expressed only at passage 0 by UC-MSCs, while they were expressed at different passages for AT-MSCs. There was no difference (P>0.05) in total ATP production between cell cultures, but the ratio between the “mitochondrial ATP Production Rate” and the “glycolytic ATP Production Rate” was higher (P<0.05) in AT- than in UC-MSCs. However, in both MSCs types the mitochondrial respiration was the main pathway of ATP production. Mitochondrial respiration and ATP turnover in UC-MSCs were higher (P<0.05) than in AT-MSCs, but both had a 100% coupling efficiency. These features and the possibility of increasing the oxygen consumption by a spare respiratory capacity of four (AT-MSCSs) and two (UC-MSCs) order of magnitude greater than basal respiration, can be taken as indicative of the cell propensity to differentiate. The findings may efficiently contribute to select the most appropriate MSCs, culture and experimental conditions for transplantation experiments in mesenchymal stem cell therapy for companion animals.

Isolation and establishment of skin-derived and mesenchymal cells from south American bat Artibeus planirostris (Chiroptera - Phyllostomidae)

Animal models represent a crucial tool for biological research, so the establishment of new cultures is fundamental for the discovery of new therapies and the understanding of mechanisms of cell development in the most diverse animals. Here, we report the successful establishment of two new primary cell cultures derived from a South American bat (Artibeus planirostris). The establishment of a new bat culture can help in the investigation of new zoonoses since bats have been proposed as carriers of these diseases. We evaluated the chromosomal stability of cells from different passages. Primary cultures were collected from ear tissues and bone marrow of A. planirostris. Cultures were expanded, and osteogenic and adipogenic inductions were conducted for 21 days. For osteogenic differentiation, the medium was supplemented with 0.1 μM dexamethasone, 3 mM β-glycerophosphate, and 10 μM L-ascorbic acid 2-phosphate. For adipogenic differentiation, the medium was supplemented with 5 μM rosiglitazone, 0.4 μM insulin, 0.1 mM indomethacin, and 0.1 μM dexamethasone. After the induction period, the cells were stained with Alizarin Red to assess osteogenic differentiation and Oil Red O to assess adipogenic differentiation. We observed the appearance of lipid droplets in adipocytes and the extracellular deposition of calcium matrix by osteocytes, indicating that bone marrow-derived cells and skin-derived cells of A. planirostris could successfully differentiate into these lineages. Also, the number of chromosomes remained stable for both primary cultures during passages 2, 4, 6, and 8.

The Anti-fibrotic and Anti-inflammatory Potential of Bone Marrow-Derived Mesenchymal Stem Cells and Nintedanib in Bleomycin-Induced Lung Fibrosis in Rats

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by progressive lung damage. Tyrosine kinase inhibitors are approved to treat people with IPF while bone marrow-derived mesenchymal stem cell therapy was previously suggested to inhibit pulmonary fibrosis through the alveolar epithelial cell repair. The present study aimed to evaluate the anti-inflammatory and anti-fibrotic effect of the bone marrow-derived mesenchymal stem cell (BM-MSC) therapy in comparison with nintedanib, a tyrosine kinase inhibitor, on improving survival in bleomycin-induced lung fibrosis in rats. Moreover, the combined therapy of BM-MSCs and nintedanib will be evaluated. In the present study, IPF was induced through intra-tracheal instillation of bleomycin (5 mg/kg) in rats then treatments were administered 14 days thereafter. Nintedanib (100 mg/kg, I.P.) was administered daily for 28 days, while BM-MSCs were injected once intravenously in tail vein in the dose 1 × 10⁶ cells/ml/rat. In the present study, both treatment regimens effectively inhibited lung fibrosis through several pathways, suppressing tumor growth factor-β (TGF-β)/SMAD3 expression which is considered the master signaling pathway. Nintedanib and BLM-MSCs exerted their anti-inflammatory effect through minimizing the expression of TNF-α and IL-6. In addition, the histopathological examination of the lung tissue showed a significant decrease in the alveolar wall thickening, in the inflammatory infiltrate, and in the collagen fiber deposition in response to either nintedanib or BM-MSC and their combination. In conclusion, the therapeutic pulmonary anti-fibrotic activity of nintedanib or BM-MSC is mediated through their anti-inflammatory properties and inhibition of SMAD-3/TGF-β expression.

Mesenchymal stem cells versus curcumin in enhancing the alterations in the cerebellar cortex of streptozocin-induced diabetic albino rats. The role of GFAP, PLC and α-synuclein

BACKGROUND

Diabetes mellitus is the disease, termed either by insulin paucity or resistance and hyperglycemia. The selection of the cerebellum was built on its specific functions. The aim of this study was to investigate a comparison between the possible therapeutic effects of MSCs and curcumin against fluctuations in the cerebellar cortex of STZ-induced diabetic albino rats.

MATERIALS AND METHODS

Forty rats were divided into five groups: control, sham control, streptozotocin-induced diabetes, diabetes and MSCs administered and diabetes and curcumin administered. Light microscopic (H&E), immune-histochemical; Glial fibrillary acidic protein (GFAP), real-time PCR; phospholipase-C (PLC) and α-synuclein, histomorphometric analysis, oxidative / anti-oxidatants; malondialdehyde (MDA)/ superoxide dismutase (SOD) glutathione (GSH) and were made.

RESULTS

The histopathological examination of the STZ-induced diabetic rats revealed alterations in the molecular, purkinje and granular layers. Abnormal organizations, vacuolation, patchy loss of purkinje cells were detected. Some purkinje cells migrated into the granular layer.Hemorrhage in pia mater outspreading to cerebellar layers is discerned. Purkinje cells showed karyorrhexis. The mean value of area percentage for GFAP immune- reactivity revealed 360 % significant increase compared to that of the control group. Also, MDA level was significantly increased while the SOD and GSH levels were significantly lower when compared to the control group. Meanwhile, mean values of PLC demonstrated significant decrease, while α-synuclein levels displayed a significant increment in the diabetic group. Administration of curcumin and MSCs extremely ameliorated the previous alterations.

CONCLUSION

the deleterious alterations on the cerebellar cortex induced by diabetes were obviously improved when treated with either MSCs or curcumin.

Potential application of aminiotic stem cells in veterinary medicine

In regenerative medicine stem cell biology has become one of the most interesting and more often studied subject. The amniotic membrane is the innermost layer of the fetal membranes and is considered a potential tool to treat many pathologies. It is used because it can be collected from discarded fetal material and is a rich source of stem cells with high proliferation and plasticity ratio capable of proliferating and differentiate in vitro. We propose to elucidate the characteristics and potencial clinical application of cells derived of amniotic membrane in veterinary medicine.

A Protocol for the Isolation, Culture, and Cryopreservation of Umbilical Cord-Derived Canine Mesenchymal Stromal Cells: Role of Cell Attachment in Long-Term Maintenance

Mesenchymal stromal cells (MSCs) hold great promise in the field of regenerative medicine due to their ability to create a variable localized anti-inflammatory effect in injuries such as Crohn's disease and osteoarthritis or by incorporation in tissue engineered constructs. Currently, the MSC literature uses rodents for preclinical disease models. There is growing interest in using naturally occurring disease in large animals for modeling human disease. By review of the canine MSCs literature, it appears that canine MSCs can be difficult to maintain in culture for extended passages and this greatly varies between tissue sources, compared with human and rodent MSCs, and limited lifespan is an obstacle for preclinical investigation and therapeutic use. Research using canine MSCs has been focused on cells derived from bone marrow or adipose tissue, and the differences in manufacturing MSCs between laboratories are problematic due to lack of standardization. To address these issues, here, a stepwise process was used to optimize canine MSCs isolation, expansion, and cryopreservation utilizing canine umbilical cord-derived MSCs. The culture protocol utilizes coating of tissue culture surfaces that increases cellular adherence, increases colony-forming units-fibroblast efficiency, and decreases population doubling times. Canine MSCs isolated with our protocol could be maintained longer than published canine MSCs methods before senescing. Our improved cryopreservation protocols produce on average >90% viable MSCs at thaw. These methods enable master-bank and working-bank scenarios for allogeneic MSC testing in naturally occurring disease in dogs.

Rat Olfactory Mucosa Mesenchymal Stem/Stromal Cells (OM-MSCs): A Characterization Study

Stem/stromal cell-based therapies are a branch of regenerative medicine and stand as an attractive option to promote the repair of damaged or dysfunctional tissues and organs. Olfactory mucosa mesenchymal stem/stromal cells have been regarded as a promising tool in regenerative therapies because of their several favorable properties such as multipotency, high proliferation rate, helpful location, and few associated ethical issues. These cells are easily accessible in the nasal cavity of most mammals, including the rat, can be easily applied in autologous treatments, and do not cope with most of the obstacles associated with the use of other stem cells. Despite this, its application in preclinical trials and in both human and animal patients is still limited because of the small number of studies performed so far and to the nonexistence of a standard and unambiguous protocol for collection, isolation, and therapeutic application. In the present work a validation of a protocol for isolation, culture, expansion, freezing, and thawing of olfactory mucosa mesenchymal stem/stromal cells was performed, applied to the rat model, as well as a biological characterization of these cells. To investigate the therapeutic potential of OM-MSCs and their eventual safe application in preclinical trials, the main characteristics of OMSC stemness were addressed.

The impact of mesenchymal stem cells on doxorubicin-induced testicular toxicity and progeny outcome of male prepubertal rats

BACKGROUND

Many therapies to treat cancer are gonadotoxic and can lead to infertility. New strategies to diminish the side effects and protective plans during and after chemotherapy are needed. Therefore, bone marrow mesenchymal stem cells (BM-MSCs) as a novel solution were investigated against doxorubicin (Dox)-induced toxicity in rat testes.

METHODS

Forty male albino prepubertal rats were divided into four groups, 10 rats per each group. The first was injected intraperitoneally with saline as control. The second group was injected intravenously with a single dose of BM-MSCs (2 × 10⁶ cells). The third was injected intraperitoneally with a single dose of Dox (5 mg/kg b.wt). The fourth was injected with both Dox and BM-MSCs as previously mentioned. Rats were cohabited each separately with an untreated adult female after 8 weeks of treatment to examine Dox effects on male's fertility.

RESULTS

BM-MSCs counteract the deleterious effects of Dox on body, testicular weight as well as sperm quality by increasing sperm concentration and reducing the rate of abnormal sperm. BM-MSCs reduced significantly the testicular oxidative stress by reducing the elevated level of malondialdehyde and increasing the antioxidant capacity. Histologically, the testicular atrophy, severe damage of spermatogenesis and the significant reduction of the diameter and germinative cell layer thickness of the seminiferous tubules caused by Dox were significantly recovered after administration of the BM-MSCs.

CONCLUSION

BM-MSCs have a significant role in restoring the structural efficiency of male reproductive system in rats after Dox treatment.

Placental Stem Cells from Domestic Animals: Translational Potential and Clinical Relevance

The field of regenerative medicine is moving toward clinical practice in veterinary science. In this context, placenta-derived stem cells isolated from domestic animals have covered a dual role, acting both as therapies for patients and as a valuable cell source for translational models. The biological properties of placenta-derived cells, comparable among mammals, make them attractive candidates for therapeutic approaches. In particular, stemness features, low immunogenicity, immunomodulatory activity, multilineage plasticity, and their successful capacity for long-term engraftment in different host tissues after autotransplantation, allo-transplantation, or xenotransplantation have been demonstrated. Their beneficial regenerative effects in domestic animals have been proven using preclinical studies as well as clinical trials starting to define the mechanisms involved. This is, in particular, for amniotic-derived cells that have been thoroughly studied to date. The regenerative role arises from a mutual tissue-specific cell differentiation and from the paracrine secretion of bioactive molecules that ultimately drive crucial repair processes in host tissues (e.g., anti-inflammatory, antifibrotic, angiogenic, and neurogenic factors). The knowledge acquired so far on the mechanisms of placenta-derived stem cells in animal models represent the proof of concept of their successful use in some therapeutic treatments such as for musculoskeletal disorders. In the next future, legislation in veterinary regenerative medicine will be a key element in order to certify those placenta-derived cell-based protocols that have already demonstrated their safety and efficacy using rigorous approaches and to improve the degree of standardization of cell-based treatments among veterinary clinicians.

Mesenchymal stem cell basic research and applications in dog medicine

The stem cells, owing to their special characteristics like self-renewal, multiplication, homing, immunomodulation, anti-inflammatory, and dedifferentiation are considered to carry an "all-in-one-solution" for diverse clinical problems. However, the limited understanding of cellular physiology currently limits their definitive therapeutic use. Among various stem cell types, currently mesenchymal stem cells are extensively studied for dog clinical applications owing to their readily available sources, easy harvesting, and ability to differentiate both into mesodermal, as well as extramesodermal tissues. The isolated, culture expanded, and characterized cells have been applied both at preclinical as well as clinical settings in dogs with variable but mostly positive results. The results, though positive, are currently inconclusive and demands further intensive research on the properties and their dependence on the applications. Further, numerous clinical conditions of dog resemble to that of human counterparts and thus, if proved rewarding in the former may act as basis of therapy for the latter. The current review throws some light on dog mesenchymal stem cell properties and their potential therapeutic applications.

Could hypoxia influence basic biological properties and ultrastructural features of adult canine mesenchymal stem /stromal cells?

The aim of the present study was to compare canine adipose tissue mesenchymal stem cells cultured under normoxic (20% O₂) and not severe hypoxic (7% O₂) conditions in terms of marker expression, proliferation rate, differentiation potential and cell morphology. Intra-abdominal fat tissue samples were recovered from 4 dogs and cells isolated from each sample were cultured under hypoxic and normoxic conditions. Proliferation rate and adhesion ability were determined, differentiation towards chondrogenic, osteogenic and adipogenic lineages was induced; the expression of CD44, CD34, DLA-DQA1, DLA-DRA1 was determined by PCR, while flow cytometry analysis for CD90, CD105, CD45 and CD14 was carried out. The morphological study was performed by transmission electron microscopy. Canine AT-MSCs, cultured under different oxygen tensions, maintained their basic biological features. However, under hypoxia, cells were not able to form spheroid aggregates revealing a reduction of their adhesivness. In both conditions, MSCs mainly displayed the same ultrastructural morphology and retained the ability to produce membrane vesicles. Noteworthy, MSCs cultivated under hypoxya revealed a huge shedding of large complex vesicles, containing smaller round-shaped vesicles. In our study, hypoxia partially influences the basic biological properties and the ultrastructural features of canine mesenchymal stem /stromal cells. Further studies are needed to clarify how hypoxia affects EVs production in term of amount and content in order to understand its contribution in tissue regenerative mechanisms and the possible employment in clinical applications. The findings of the present work could be noteworthy for canine as well as for other mammalian species.

Current Status of Canine Umbilical Cord Blood-Derived Mesenchymal Stem Cells in Veterinary Medicine

Stem cell therapy has prompted the expansion of veterinary medicine both experimentally and clinically, with the potential to contribute to contemporary treatment strategies for various diseases and conditions for which limited or no therapeutic options are presently available. Although the application of various types of stem cells, such as bone marrow-derived mesenchymal stem cells (BM-MSCs), adipose tissue-derived mesenchymal stem cells (AT-MSCs), and umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), has promising potential to improve the health of different species, it is crucial that the benefits and drawbacks are completely evaluated before use. Umbilical cord blood (UCB) is a rich source of stem cells; nonetheless, isolation of mesenchymal stem cells (MSCs) from UCB presents technical challenges. Although MSCs have been isolated from UCB of diverse species such as human, equine, sheep, goat, and canine, there are inherent limitations of using UCB from these species for the expansion of MSCs. In this review, we investigated canine UCB (cUCB) and compared it with UCB from other species by reviewing recent articles published from February 2003 to June 2017 to gain an understanding of the limitations of cUCB in the acquisition of MSCs and to determine other suitable sources for the isolation of MSCs from canine. Our review indicates that cUCB is not an ideal source of MSCs because of insufficient volume and ethical issues. However, canine reproductive organs discarded during neutering may help broaden our understanding of effective isolation of MSCs. We recommend exploring canine reproductive and adipose tissue rather than UCB to fulfill the current need in veterinary medicine for the well-designed and ethically approved source of MSCs.

Mesenchymal Stem Cells Contribute to Improvement of Renal Function in a Canine Kidney Injury Model

BACKGROUND/AIM

The kidney excretes waste materials and regulates important metabolic functions, and renal disorders constitute a significant medical problem and can result in fatalities. In the present study, mesenchymal stem cells derived from canine umbilical cord blood (cUCB-MSCs) were isolated and evaluated for their ability to improve renal function in a canine model of acute kidney injury (AKI).

MATERIALS AND METHODS

The canine AKI model was developed by i.v. injection of cisplatin and gentamycin into 14 male beagle dogs. cUCB-MSCs were administered into the renal corticomedullary junction following AKI induction. Survival time, clinical signs, blood analysis and histological parameters were analyzed.

RESULTS

The group treated with AKI plus cUCB-MSCs had decreased blood urea nitrogen and creatinine levels, and showed an extended life-span and improved histological manifestations. MSCs were detected around the tubules of these kidneys at the histological level.

CONCLUSION

Taken together, our findings suggest that cUCB-MSCs could be an alternative therapeutic agent for canine AKI.

Phase I-II Clinical Trial Assessing Safety and Efficacy of Umbilical Cord Blood Mononuclear Cell Transplant Therapy of Chronic Complete Spinal Cord Injury

Umbilical cord blood-derived mononuclear cell (UCB-MNC) transplants improve recovery in animal spinal cord injury (SCI) models. We transplanted UCB-MNCs into 28 patients with chronic complete SCI in Hong Kong (HK) and Kunming (KM). Stemcyte Inc. donated UCB-MNCs isolated from human leukocyte antigen (HLA ≥4:6)-matched UCB units. In HK, four patients received four 4-μl injections (1.6 million cells) into dorsal entry zones above and below the injury site, and another four received 8-μl injections (3.2 million cells). The eight patients were an average of 13 years after C5-T10 SCI. Magnetic resonance diffusion tensor imaging of five patients showed white matter gaps at the injury site before treatment. Two patients had fiber bundles growing across the injury site by 12 months, and the rest had narrower white matter gaps. Motor, walking index of SCI (WISCI), and spinal cord independence measure (SCIM) scores did not change. In KM, five groups of four patients received four 4-μl (1.6 million cells), 8-μl (3.2 million cells), 16-μl injections (6.4 million cells), 6.4 million cells plus 30 mg/kg methylprednisolone (MP), or 6.4 million cells plus MP and a 6-week course of oral lithium carbonate (750 mg/day). KM patients averaged 7 years after C3-T11 SCI and received 3-6 months of intensive locomotor training. Before surgery, only two patients walked 10 m with assistance and did not need assistance for bladder or bowel management before surgery. The rest could not walk or do their bladder and bowel management without assistance. At about a year (41-87 weeks), WISCI and SCIM scores improved: 15/20 patients walked 10 m ( p = 0.001) and 12/20 did not need assistance for bladder management ( p = 0.001) or bowel management ( p = 0.002). Five patients converted from complete to incomplete (two sensory, three motor; p = 0.038) SCI. We conclude that UCB-MNC transplants and locomotor training improved WISCI and SCIM scores. We propose further clinical trials.

Isolation, culture, characterization, and osteogenic differentiation of canine endometrial mesenchymal stem cell

Aim

In this study, the canine endometrium tissue is characterized for its stem cell properties such as adherence to tissue culture plate (plasticity), short population doubling time, serial clonal passaging, long-term culturing properties, stem cell marker expression, and multilineage differentiation potential.

Materials and Methods

The present work describes a novel isolation protocol for obtaining mesenchymal stem cells from the uterine endometrium and is compared with cells derived from umbilical cord matrix as a positive control. These cells are clonogenic, can undergo several population doublings in vitro, and can be differentiated to the osteocytes in mature mesenchymal tissues when grown in osteogenic differentiation media as detected by Alizarin Red-S staining.

Results

It is reported for the first time that the cells derived from the canine endometrium (e-multipotent stem cells [MSCs]) were able to differentiate into a heterologous cell type: Osteocytes, thus demonstrating the presence of MSCs. Thus, the endometrium may be told as a potential source of MSCs which can be used for various therapeutic purposes.

Conclusion

The endometrium can be used as a potential source of MSCs, which can be used for various therapeutic purposes.

Mammalian MSC from selected species: Features and applications

Mesenchymal stromal/stem cells (MSC) are promising candidates for cellular therapy of different diseases in humans and in animals. Following the guidelines of the International Society for Cell Therapy, human MSC may be identified by expression of a specific panel of cell surface markers (CD105+, CD73+, CD90+, CD34-, CD14-, or CD11b-, CD79- or CD19-, HLA-DR-). In addition, multiple differentiation potential into at least the osteogenic, adipogenic, and chondrogenic lineage is a main criterion for MSC definition. Human MSC and MSC of a variety of mammals isolated from different tissues meet these criteria. In addition to the abovementioned, they express many more cell surface markers. Yet, these are not uniquely expressed by MSC. The gross phenotypic appearance like marker expression and differentiation potential is similar albeit not identical for MSC from different tissues and species. Similarly, MSC may feature different biological characteristics depending on the tissue source and the isolation and culture procedures. Their versatile biological qualities comprising immunomodulatory, anti-inflammatory, and proregenerative capacities rely largely on the migratory and secretory capabilities of MSC. They are attracted to sites of tissue lesion and secrete factors to promote self-repair of the injured tissue. This is a big perspective for clinical MSC applications in both veterinary and human medicine. Phase I/II clinical trials have been initiated to assess safety and feasibility of MSC therapies in acute and chronic disease settings. Yet, since the mode of MSC action in a specific disease environment is still unknown at large, it is mandatory to unravel the response of MSC from a given source onto a specific disease environment in suitable animal models prior to clinical applications. © 2017 International Society for Advancement of Cytometry.

ISOLAMENTO E CULTIVO DE CÉLULAS TRONCO MESENQUIMAIS EXTRAÍDAS DO TECIDO ADIPOSO E DA MEDULA ÓSSEA DE CÃES

Resumo Objetivou-se estabelecer um protocolo para extração, cultivo e expansão de células tronco mesenquimais (CTM), utilizando-se 3,0 mL da medula óssea e 3,0 cm3 de tecido adiposo do subcutâneo de três cães machos com seis meses de idade. As amostras foram processadas e as células extraídas e cultivadas em DMEM. Para comprovação do isolamento de CTM, procedeu-se a caracterização fenotípica e a diferenciação osteogênica, adipogênica e condrogênica. As células isoladas apresentaram morfologia alongada e fusiforme e capacidade de se diferenciar em osteoblastos, adipócitos e condrócitos. A caracterização fenotípica revelou alta expressão de marcadores de CTM CD90 (80,04%) e CD29 (96%) nas células de origem medular e CD90 (60,94%) e CD29 (77,08%) nas de origem adiposa. A expressão de marcadores hematopoiéticos foi baixa tanto nas células de origem medular CD45 (1,45%) e CD34 (1,53%), quanto nas de origem adiposa CD45 (1,45%) e CD34 (1,53%). As modificações e adaptações realizadas nos protocolos clássicos simplificaram o processo e foram eficientes, permitindo o isolamento e cultivo de CTM da medula óssea e do tecido adiposo de cães.

Effect of canine mesenchymal stromal cells loaded with paclitaxel on growth of canine glioma and human glioblastoma cell lines

This study investigated whether canine mesenchymal stromal cells (cMSCs) are able to take up and release paclitaxel (PTX) in active form, and therefore whether they have potential as a tool for therapeutic delivery of this drug. cMSCs from bone marrow and adipose tissue were isolated, expanded and characterised phenotypically. cMSCs were loaded with PTX (cMSCs-PTX) and their capacity for release of PTX was determined by their effect on proliferation of cancer cells. cMSCs-PTX derived from bone marrow and adipose tissue were able to take up and then release active PTX. cMSCs-PTC inhibited proliferation of the canine glioma cell line J3T, and the human glioblastoma cell lines T98G and U87MG. The potential of canine cMSCs-PTX for treatment of canine gliomas should be investigated further.

Durable Control of Autoimmune Diabetes in Mice Achieved by Intraperitoneal Transplantation of "Neo-Islets," Three-Dimensional Aggregates of Allogeneic Islet and "Mesenchymal Stem Cells"

Novel interventions that reestablish endogenous insulin secretion and thereby halt progressive end-organ damage and prolong survival of patients with autoimmune Type 1 diabetes mellitus (T1DM) are urgently needed. While this is currently accomplished with allogeneic pancreas or islet transplants, their utility is significantly limited by both the scarcity of organ donors and life-long need for often-toxic antirejection drugs. Coadministering islets with bone marrow-derived mesenchymal stem cells (MSCs) that exert robust immune-modulating, anti-inflammatory, anti-apoptotic, and angiogenic actions, improves intrahepatic islet survival and function. Encapsulation of insulin-producing cells to prevent immune destruction has shown both promise and failures. Recently, stem cell-derived insulin secreting β-like cells induced euglycemia in diabetic animals, although their clinical use would still require encapsulation or anti-rejection drugs. Instead of focusing on further improvements in islet transplantation, we demonstrate here that the intraperitoneal administration of islet-sized "Neo-Islets" (NIs), generated by in vitro coaggregation of allogeneic, culture-expanded islet cells with high numbers of immuno-protective and cyto-protective MSCs, resulted in their omental engraftment in immune-competent, spontaneously diabetic nonobese diabetic (NOD) mice. This achieved long-term glycemic control without immunosuppression and without hypoglycemia. In preparation for an Food and Drug Administration-approved clinical trial in dogs with T1DM, we show that treatment of streptozotocin-diabetic NOD/severe combined immunodeficiency mice with identically formed canine NIs produced durable euglycemia, exclusively mediated by dog-specific insulin. We conclude that this novel technology has significant translational relevance for canine and potentially clinical T1DM as it effectively addresses both the organ donor scarcity (>80 therapeutic NI doses/donor pancreas can be generated) and completely eliminates the need for immunosuppression. Stem Cells Translational Medicine 2017;6:1631-1643.

Functionalized carbon nanotubes as suitable scaffold materials for proliferation and differentiation of canine mesenchymal stem cells

In the field of regenerative medicine, numerous potential applications of mesenchymal stem cells (MSCs) can be envisaged, due to their ability to differentiate into a range of tissues on the basis of the substrate on which they grow. With the advances in nanotechnology, carbon nanotubes (CNTs) have been widely explored for use as cell culture substrate in tissue engineering applications. In this study, canine bone marrow-derived MSCs were considered as the cellular model for an in vitro study to elucidate the collective cellular processes, using three different varieties of thin films of functionalized carbon nanotubes (COOH-single-walled CNTs [SWCNTs], COOH-multiwalled CNTs [MWCNTs] and polyethylene glycol [PEG]-SWCNTs), which were spray dried onto preheated cover slips. Cells spread out better on the CNT films, resulting in higher cell surface area and occurrence of filopodia, with parallel orientation of stress fiber bundles. Canine MSCs proliferated at a slower rate on all types of CNT substrates compared to the control, but no decline in cell number was noticed during the study period. Expression of apoptosis-associated genes decreased on the CNT substrates as time progressed. On flow cytometry after AnnexinV-fluorescein isothiocyanate/propidium iodide (PI) staining, total number of apoptotic and necrotic cells remained lower in COOH-functionalized films compared to PEG-functionalized ones. Collectively, these results indicate that COOH-MWCNT substrate provided an environment of low cytotoxicity. Canine MSCs were further induced to differentiate along osteogenic, chondrogenic, and neuronal lineages by culturing under specific differentiation conditions. The cytochemical and immunocytochemical staining results, as well as the expression of the bone marker genes, led us to hypothesize that the COOH-MWCNT substrate acted as a better cue, accelerating the osteogenic differentiation process. However, while chondrogenesis was promoted by COOH-SWCNT, neuronal differentiation was promoted by both COOH-SWNCT and COOH-MWCNT. Taken together, these findings suggest that COOH-functionalized CNTs represent a promising scaffold component for future utilization in the selective differentiation of canine MSCs in regenerative medicine.

Can mesenchymal stem cells pretreated with platelet-rich plasma modulate tissue remodeling in a rat with burned skin?

Our aim was to study the effect of platelet-rich plasma (PRP) on the proliferation of bone-marrow-derived mesenchymal stem cells (BM-MSCs) and to investigate their roles in the healing of experimental burn injury and the possible mechanism of action. Our work was divided into in-vitro and in-vivo studies. The in-vitro study included untreated MSCs and MSCs treated with PRP. Levels of TGF-β and cell proliferation were assessed. In the in-vivo study, 72 rats were distributed equally among 6 groups: control, burn, burn with MSCs, burn with PRP, burn with both MSCs and PRP, and burn with MSCs pretreated with PRP. On the 7th and 20th day after injury, the serum levels of transforming growth factor beta (TGF-β) and tumor necrosis factor alpha (TNF-α), as well as interleukin-10 (IL-10) levels in skin tissue were measured by ELISA; histopathology and gene expression of MMP-1, TIMP-2, Ang-1, Ang-2, and vimentin by real-time PCR were performed in all groups. In vitro: proliferation of MSCs and TGF-β increased in the PRP-treated group compared with the control group. In vivo: Ang-1, Ang-2, and vimentin were upregulated, whereas MMP-1 and TIMP-2 were downregulated. TGF-β and IL-10 were increased, whereas TNF-α was decreased in all treated groups with more significance in MSCs and PRP on day 20. Histopathology of burn skin was improved in all treated groups, particularly in MSCs pretreated with PRP 20 days post-burn.

Bone marrow-derived mesenchymal stem cells ameliorate sodium nitrite-induced hypoxic brain injury in a rat model

Sodium nitrite (NaNO₂) is an inorganic salt used broadly in chemical industry. NaNO₂ is highly reactive with hemoglobin causing hypoxia. Mesenchymal stem cells (MSCs) are capable of differentiating into a variety of tissue specific cells and MSC therapy is a potential method for improving brain functions. This work aims to investigate the possible therapeutic role of bone marrow-derived MSCs against NaNO₂ induced hypoxic brain injury. Rats were divided into control group (treated for 3 or 6 weeks), hypoxic (HP) group (subcutaneous injection of 35 mg/kg NaNO₂ for 3 weeks to induce hypoxic brain injury), HP recovery groups N-2wR and N-3wR (treated with the same dose of NaNO₂ for 2 and 3 weeks respectively, followed by 4-week or 3-week self-recovery respectively), and MSCs treated groups N-2wSC and N-3wSC (treated with the same dose of NaNO₂ for 2 and 3 weeks respectively, followed by one injection of 2 × 10⁶ MSCs via the tail vein in combination with 4 week self-recovery or intravenous injection of NaNO₂ for 1 week in combination with 3 week self-recovery). The levels of neurotransmitters (norepinephrine, dopamine, serotonin), energy substances (adenosine monophosphate, adenosine diphosphate, adenosine triphosphate), and oxidative stress markers (malondialdehyde, nitric oxide, 8-hydroxy-2'-deoxyguanosine, glutathione reduced form, and oxidized glutathione) in the frontal cortex and midbrain were measured using high performance liquid chromatography. At the same time, hematoxylin-eosin staining was performed to observe the pathological change of the injured brain tissue. Compared with HP group, pathological change of brain tissue was milder, the levels of malondialdehyde, nitric oxide, oxidized glutathione, 8-hydroxy-2'-deoxyguanosine, norepinephrine, serotonin, glutathione reduced form, and adenosine triphosphate in the frontal cortex and midbrain were significantly decreased, and glutathione reduced form/oxidized glutathione and adenosine monophosphate/adenosine triphosphate ratio were significantly increased in the MSCs treated groups. These findings suggest that bone marrow-derived MSCs exhibit neuroprotective effects against NaNO₂-induced hypoxic brain injury through exerting anti-oxidative effects and providing energy to the brain.

Isolation, molecular characterization, and in vitro differentiation of bovine Wharton jelly-derived multipotent mesenchymal cells

Extrafetal tissues are a noncontroversial and inexhaustible source of mesenchymal stem cells that can be harvested noninvasively at low cost. In the veterinary field, as in man, stem cells derived from extrafetal tissues express plasticity, reduced immunogenicity, and have high anti-inflammatory potential making them promising candidates for treatment of many diseases. Umbilical cord mesenchymal cells have been isolated and characterized in different species and have recently been investigated as potential candidates in regenerative medicine. In this study, cells derived from bovine Wharton jelly (WJ) were isolated for the first time by enzymatic methods, frozen/thawed, cultivated for at least 10 passages, and characterized. Wharton jelly-derived cells readily attached to plastic culture dishes displaying typical fibroblast-like morphology and, although their proliferative capacity decreased to the seventh passage, these cells showed a mean doubling time of 34.55 ± 6.33 hours and a mean frequency of one colony-forming unit fibroblast like for every 221.68 plated cells. The results of molecular biology studies and flow cytometry analyses revealed that WJ-derived cells showed the typical antigen profile of mesenchymal stem cells and were positive for CD29, CD44, CD105, CD166, Oct-4, and c-Myc. They were negative for CD34 and CD14. Remarkably, WJ-derived cells showed differentiation ability. After culture in induced media, WJ-derived cells were able to differentiate into osteogenic, adipogenic, chondrogenic, and neurogenic lines as shown by positive staining and expression of specific markers. On polymerase chain reaction analysis, these cells were negative for MHC-II and positive for MHC-I, thus reinforcing the role of extrafetal tissue as an allogenic source for bovine cell-based therapies. These results provide evidence that bovine WJ-derived cells may have the potential to differentiate to repair damaged tissues and reinforce the importance of extrafetal tissues as stem cell sources in veterinary regenerative medicine. A more detailed evaluation of their immunologic properties is necessary to better understand their potential role in cellular therapy.

Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Contribute to Chondrogenesis in Coculture with Chondrocytes

Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) have been shown as the most potential stem cell source for articular cartilage repair. In this study, we aimed to develop a method for long-term coculture of human articular chondrocytes (hACs) and hUCB-MSCs at low density in vitro to determine if the low density of hACs could enhance the hUCB-MSC chondrogenic differentiation as well as to determine the optimal ratio of the two cell types. Also, we compared the difference between direct coculture and indirect coculture at low density. Monolayer cultures of hUCB-MSCs and hACs were investigated at different ratios, at direct cell-cell contact groups for 21 days. Compared to direct coculture, hUCB-MSCs and hACs indirect contact culture significantly increased type II collagen (COL2) and decreased type I collagen (COL1) protein expression levels. SRY-box 9 (SOX9) mRNA levels and protein expression were highest in indirect coculture. Overall, these results indicate that low density direct coculture induces fibrocartilage. However, indirect coculture in conditioned chondrocyte cell culture medium can increase expression of chondrogenic markers and induce hUCB-MSCs differentiation into mature chondrocytes. This work demonstrates that it is possible to promote chondrogenesis of hUCB-MSCs in combination with hACs, further supporting the concept of novel coculture strategies for tissue engineering.

I, Pandey S, Panda BSK, Thakur N, Sarkar M, Chandra V, Saikumar G, Sharma GT. A Comparative Study of Growth Kinetics, In Vitro Differentiation Potential and Molecular Characterization of Fetal Adnexa Derived Caprine Mesenchymal Stem Cells

The present study was conducted with an objective of isolation, in vitro expansion, growth kinetics, molecular characterization and in vitro differentiation of fetal adnexa derived caprine mesenchymal stem cells. Mid-gestation gravid caprine uteri (2–3 months) were collected from abattoir to derive mesenchymal stem cells (MSCs) from fetal adnexa {amniotic fluid (cAF), amniotic sac (cAS), Wharton’s jelly (cWJ) and cord blood (cCB)} and expanded in vitro. These cultured MSCs were used at the 3^rd passage (P3) to study growth kinetics, localization as well as molecular expression of specific surface antigens, pluripotency markers and mesenchymal tri-lineage differentiation. In comparison to cAF and cAS MSCs, cWJ and cCB MSCs showed significantly (P<0.05) higher clonogenic potency, faster growth rate and low population doubling (PDT) time. All the four types of MSCs were positive for alkaline phosphatase (AP) and differentiated into chondrogenic, osteogenic, and adipogenic lineages. These stem cells expressed MSC surface antigens (CD73, CD90 and CD105) and pluripotency markers (Oct4, Sox2, Nanog, KLF, cMyc, FoxD3) but did not express CD34, a hematopoietic stem cell marker (HSC) as confirmed by RT-PCR, immunocytochemistry and flow cytometric analysis. The relative mRNA expression of MSC surface antigens (CD73, CD90 and CD105) was significantly (P<0.05) higher in cWJ MSCs compared to the other cell lines. The mRNA expression of Oct4 was significantly (P<0.05) higher in cWJ, whereas mRNA expression of KLF and cMyc was significantly (P<0.05) higher in cWJ and cAF than that of cAS and cCB. The comparative assessment revealed that cWJ MSCs outperformed MSCs from other sources of fetal adnexa in terms of growth kinetics, relative mRNA expression of surface antigens, pluripotency markers and tri-lineage differentiation potential, hence, these MSCs could be used as a preferred source for regenerative medicine.

Estudo comparativo da diferenciação osteogênica das células tronco mesenquimais da medula óssea e do tecido adiposo de cães adultos

Resumo: O objetivo deste estudo foi comparar o potencial osteogênico das células tronco mesenquimais extraídas da medula óssea (CTM-MO) com as do tecido adiposo (CTM-AD) de cães adultos. As células foram caracterizadas fenotipicamente quanto à expressão de CD29, CD90, CD34 e CD45 e submetidas à diferenciação adipogênica e condrogênica por 21 dias e osteogênica por 7, 14 e 21 dias. Foram constituídos quatro grupos: 1) CTM-MO em meio osteogênico, 2) CTM-MO em meio basal, 3) CTM-AD em meio osteogênico e 4) CTM-AD em meio basal. Aos 7, 14 e 21 dias de diferenciação osteogênica as culturas foram submetidas às avaliações da conversão de MTT em formazan, da atividade da fosfatase alcalina (FA), da síntese de colágeno e de matriz mineralizada, avaliação do número de células por campo e foram quantificados os transcritos gênicos para osterix, sialoproteina óssea (BSP), osteonectina (ON) e osteocalcina (OC). Tanto as células extraídas da medula óssea quanto do tecido adiposo mostraram elevada expressão de marcadores para células tronco e baixa expressão de marcadores de células hematopoiéticas (menor que 2%). Além disso, foram capazes de se diferenciar em osteoblastos, condrócitos e adipócitos. As CTM-AD submetidas à diferenciação osteogênica mostraram maior conversão do MTT em formazan que as CTM-MO, sob mesmas condições aos 7 e 21 dias. O número de células por campo, a atividade da FA, a síntese de colágeno e de matriz mineralizada foram superior nas CTM-AD em diferenciação, em relação às CTM-MO sob as mesmas condições, em todos os tempos estudados. As expressões de osterix, BSP e OC foram predominantemente superiores nas CTM-MO diferenciadas, mas a expressão de ON foi superior nas CTM-AD diferenciadas aos 7, 14 e 21 dias. Conclui-se que as CTM-AD apresentam maior potencial osteogênico que as CTM-MO quando extraídas de cães adultos.

Does the Bovine Pre-Ovulatory Follicle Harbor Progenitor Stem Cells?

Recent studies have revealed the presence of a mesenchymal stem cell (MSC) population in human and in gilt granulosa cells (GCs), thus increasing the interest in identifying the same population in the bovine species. We first isolated GCs by scraping from bovine preovulatory follicles and then tested several different media to define the ideal conditions to select granulosa-derived stem cells. Although expressing MSC-associated markers, none of the media tested proven to be efficient in selecting MSC-like cells that were able to differentiate into mesodermic or ectodermic lineages. We performed another experimental approach exposing cells to a chemical stress, such as lowering of pH, as a system to select a more plastic population. Following the treatment, granulosa-specific granulose markers [follicle-stimulating hormone receptor (FSHR), follistatin (FST), and leukemia inhibitory factor receptor (LIFR)] were lost in bovine GCs, whereas an increase in multi- (CD29, CD44, CD73) and pluripotent (Oct-4 and c-Myc) genes was noticed. The stress allowed up-regulation of tumor necrosis factor-α and interleukin-1β expression and the dedifferentiation of GCs, which was demonstrated by differentiation studies. Indeed, pH-treated cells were able to differentiate into the mesodermic and ectodermic lineages, thus suggesting that the chemical stress allows for the selection of cells that are more prone to adjust and respond to the environmental changes.

Therapeutic efficacy of differentiated versus undifferentiated mesenchymal stem cells in experimental type I diabetes in rat

Selective MSCs differentiation protocol into pancreatic beta cells was conducted in the present study using exendin-4 and TGF-beta. Differentiated and undifferentiated MSCs were assessed in experimental type I diabetes in rats. Ninety female white albino rats were included in the study and divided equally (n=15/group) into 6 groups: healthy control, healthy control rats received acellular tissue culture medium, diabetic rats, diabetic rats received acellular tissue culture medium, diabetic rats received undifferentiated MSCs and diabetic rats received differentiated MSCs. Therapeutic efficacy of undifferentiated versus differentiated MSCs was evaluated via assessment of quantitative gene expressions of insulin1, insulin 2, Smad-2, Smad-3, PDX-1, PAX-4, neuroD. Blood glucose and insulin hormone levels were also assessed. Results showed that quantitative gene expressions of all studied genes showed significant decrease in diabetic rat groups. Use of undifferentiated and differentiated MSCs led to a significant elevation of expression levels of all genes with more superior effect with differentiated MSCs except smad-2 gene. As regards insulin hormone levels, use of either undifferentiated or differentiated MSCs led to a significant elevation of its levels with more therapeutic effect with differentiated MSCs. Blood glucose levels were significantly decreased with both undifferentiated and differentiated MSCs in comparison to diabetic groups but its levels were normalized 2 months after injection of differentiated MSCs. In conclusion, use of undifferentiated or differentiated MSCs exhibited significant therapeutic potentials in experimental type I diabetes in rats with more significant therapeutic effect with the use of differentiated MSCs.

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Differentiated MSCs exhibited significant therapeutic potentials in type I diabetes.

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TGF-beta1 and exendin-4 enhance MSCs differentiation into pancreatic beta cells.

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Pancreatic lineage is evaluated by gene expressions of insulin-1, insulin-2.

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Pancreatic differentiation is evaluated by expressions of PDX-1, PAX-4 and NeuroD.

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Differentiated MSCs have more therapeutic potentials than undifferentiated MSCs.

Chondrogenic potential and anti-senescence effect of hypoxia on canine adipose mesenchymal stem cells

Mesenchymal stem cells (MSCs) have the ability to differentiate into multi-lineage cells, which confers great promise for use in regenerative medicine. In this study, canine adipose MSCs (cAD-MSCs) were isolated from canine adipose tissue. These cells clearly represented stemness (Oct4, Sox2, and Nanog) and differentiation potential into the mesoderm (adipocytes, chondrocytes, and osteoblasts) at early passages. The aim of this study was to evaluate the effects of hypoxia on the differentiation potential into mesoderm, and the expression of anti-apoptotic genes associated with cell survival for the optimal culturing of MSCs. We observed that the proliferation of the cAD-MSCs meaningfully increased when cultured under hypoxic condition than in normoxic condition, during 7 consecutive passages. Also, we found that hypoxia strongly expressed anti-senescence related genes such as HDAC1 (histone deacetylase 1), DNMT1 (DNA (cytosine-5)-methyltransferase 1), Bcl-2 (inhibitor of apoptosis), TERT (telomerase reverse transcriptase), LDHA (lactate dehydrogenase A), SLC2A1 (glucose transporter), and DKC1 (telomere holoenzyme complex) and differentiation potential of cAD-MSCs into chondrocytes, than seen under the normoxic culture conditions. We also examined the multipotency of hypoxic conditioned MSCs using quantitative real-time RT-PCR. We found that the expression levels of stemness genes such as Oct-4, Nanog, and Sox-2 were increased in hypoxic condition when compared to the normoxic condition. Collectively, these results suggest that hypoxic conditions have the ability to induce proliferation of MSCs and augment their chondrogenic potential. This study suggests that cell proliferation of cAD-MSC under hypoxia could be beneficial, when considering these cells for cell therapies of canine bone diseases.

Canine Platelet Lysate Is Inferior to Fetal Bovine Serum for the Isolation and Propagation of Canine Adipose Tissue- and Bone Marrow-Derived Mesenchymal Stromal Cells

Background

Mesenchymal stromal cells (MSC) are increasingly investigated for their clinical utility in dogs. Fetal bovine serum (FBS) is a common culture supplement used for canine MSC expansion. However, FBS content is variable, its clinical use carries risk of an immune response, and its cost is increasing due to global demand. Platelet lysate (PL) has proven to be a suitable alternative to FBS for expansion of human MSC.

Hypothesis and Objectives

We hypothesized that canine adipose tissue (AT) and bone marrow (BM) MSC could be isolated and expanded equally in PL and FBS at conventionally-used concentrations with differentiation of these MSC unaffected by choice of supplement. Our objectives were to evaluate the use of canine PL in comparison with FBS at four stages: 1) isolation, 2) proliferation, 3) spontaneous differentiation, and 4) directed differentiation.

Results

1) Medium with 10% PL was unable to isolate MSC. 2) MSC, initially isolated in FBS-supplemented media, followed a dose-dependent response with no significant difference between PL and FBS cultures at up to 20% (AT) or 30% (BM) enrichment. Beyond these respective peaks, proliferation fell in PL cultures only, while a continued dose-dependent proliferation response was noted in FBS cultures. 3) Further investigation indicated PL expansion culture was inducing spontaneous adipogenesis in concentrations as low as 10% and as early as 4 days in culture. 4) MSC isolated in FBS, but expanded in either FBS or PL, maintained ability to undergo directed adipogenesis and osteogenesis, but not chondrogenesis.

Conclusions/Significance

Canine PL did not support establishment of MSC colonies from AT and BM, nor expansion of MSC, which appear to undergo spontaneous adipogenesis in response to PL exposure. In vivo studies are warranted to determine if concurrent use of MSC with any platelet-derived products such as platelet-rich plasma are associated with synergistic, neutral or antagonistic effects.

Osteogenic potential of mesenchymal cells derived from canine umbilical cord matrix co-cultured with platelet-rich plasma and demineralized bone matrix

Canine mesenchymal cells (MSCs) derived from Wharton's jelly were co-cultured, then supplemented or not supplemented with platelet rich plasma (PRP) and demineralized bone matrix (DBM) to verify osteogenic differentiation. Osteoblastic differentiation followed by mineralized bone matrix production was found to be significantly higher (p < 0.05) when MSCs were associated with PRP/DBM in culture after 14-21-days of induction. Osteopontin and osteocalcin gene expression were significantly superior (p < 0.05) under the same culture conditions after 21 days of observation. In conclusion, addition of PRP to DBM co-cultured with MSCs successfully induced osteogenesis in vitro.

Large-scale expansion of Wharton's jelly-derived mesenchymal stem cells on gelatin microbeads, with retention of self-renewal and multipotency characteristics and the capacity for enhancing skin wound healing

INTRODUCTION

Successful stem cell therapy relies on large-scale generation of stem cells and their maintenance in a proliferative multipotent state. This study aimed to establish a three-dimension culture system for large-scale generation of hWJ-MSC and investigated the self-renewal activity, genomic stability and multi-lineage differentiation potential of such hWJ-MSC in enhancing skin wound healing.

METHODS

hWJ-MSC were seeded on gelatin microbeads and cultured in spinning bottles (3D). Cell proliferation, karyotype analysis, surface marker expression, multipotent differentiation (adipogenic, chondrogenic, and osteogenic potentials), and expression of core transcription factors (OCT4, SOX2, NANOG, and C-MYC), as well as their efficacy in accelerating skin wound healing, were investigated and compared with those of hWJ-MSC derived from plate cultres (2D), using in vivo and in vitro experiments.

RESULTS

hWJ-MSC attached to and proliferated on gelatin microbeads in 3D cultures reaching a maximum of 1.1-1.30×10(7) cells on 0.5 g of microbeads by days 8-14; in contrast, hWJ-MSC derived from 2D cultures reached a maximum of 6.5 -11.5×10(5) cells per well in a 24-well plate by days 6-10. hWJ-MSC derived by 3D culture incorporated significantly more EdU (P<0.05) and had a significantly higher proliferation index (P<0.05) than those derived from 2D culture. Immunofluorescence staining, real-time PCR, flow cytometry analysis, and multipotency assays showed that hWJ-MSC derived from 3D culture retained MSC surface markers and multipotency potential similar to 2D culture-derived cells. 3D culture-derived hWJ-MSC also retained the expression of core transcription factors at levels comparable to their 2D culture counterparts. Direct injection of hWJ-MSC derived from 3D or 2D cultures into animals exhibited similar efficacy in enhancing skin wound healing.

CONCLUSIONS

Thus, hWJ-MSC can be expanded markedly in gelatin microbeads, while retaining MSC surface marker expression, multipotent differential potential, and expression of core transcription factors. These cells also efficiently enhanced skin wound healing in vivo, in a manner comparable to that of hWJ-MSC obtained from 2D culture.

Stem cells from foetal adnexa and fluid in domestic animals: an update on their features and clinical application

Over the past decade, stem cell research has emerged as an area of major interest for its potential in regenerative medicine applications. This is in constant need of new cell sources to conceive regenerative medicine approaches for diseases that are still without therapy. Scientists drew the attention towards alternative sources such as foetal adnexa and fluid, as these sources possess many advantages: first of all, cells can be extracted from discarded foetal material and it is non-invasive and inexpensive for the patient; secondly, abundant stem cells can be obtained; and finally, these stem cell sources are free from ethical considerations. Cells derived from foetal adnexa and fluid preserve some of the characteristics of the primitive embryonic layers from which they originate. Many studies have demonstrated the differentiation potential in vitro and in vivo towards mesenchymal and non-mesenchymal cell types; in addition, the immune-modulatory properties make these cells a good candidate for allo- and xenotransplantation. Naturally occurring diseases in domestic animals can be more ideal as disease model of human genetic and acquired diseases and could help to define the potential therapeutic use efficiency and safety of stem cells therapies. This review offers an update on the state of the art of characterization of domestic animals' MSCs derived from foetal adnexa and fluid and on the latest findings in pre-clinical or clinical setting of the stem cell populations isolated from these sources.

Adipose-derived stem cells from both visceral and subcutaneous fat deposits significantly improve contractile function of infarcted rat hearts

Adipose-derived stem cells (ASCs) from subcutaneous and visceral adipose tissues have been studied individually. No studies have compared their abilities in treatment of heart failure. This study was designed to evaluate whether ASCs from the two sources could provide a long-term improvement of cardiac function in infarcted hearts. Rat subcutaneous and visceral adipose tissues were excised for isolation of ASCs. Morphology, yield, proliferation, surface markers, differentiation, and cytokine secretion of the subcutaneous ASCs (S-ASCs) and visceral ASCs (V-ASCs) were analyzed. Then a rat model of myocardial infarction (MI) was established by a coronary occlusion. Seven days after occlusion, S-ASCs (n = 22), V-ASCs (n = 22), and Dulbecco's modified Eagle medium (DMEM, n = 20) were injected into the infarct rim, respectively. Cardiac function was then monitored with MRI for up to 6 months. The hearts were then removed for histological assessments. The yield of V-ASCs per gram of the visceral adipose depot was significantly greater than that of S-ASCs in 1 g of the subcutaneous adipose depot. On the other hand, the S-ASCs showed a greater proliferation rate and colony-forming unit relative to the V-ASCs. In addition, the infarcted hearts treated with either S-ASCs or V-ASCs showed a significantly greater left ventricular ejection fraction (LVEF) than those treated with DMEM at 4 weeks and 6 months following the cell/DMEM transplantation. Moreover, the infarct sizes of both S-ASC- and V-ASC-treated hearts were significantly smaller than that in the DMEM-treated hearts. MRI showed the implanted ASCs at the end of 6 months of recovery. Despite the differences in cell yield, proliferation, and colony formation capacity, both S-ASCs and V-ASCs provide a long-lasting improvement of cardiac contractile function in infarcted hearts. We conclude that the subcutaneous and visceral adipose tissues are equally effective cell sources for cell therapy of heart failure.

Evaluation of mesenchymal stem cells in treatment of infertility in male rats

INTRODUCTION

The present study aimed to elucidate the therapeutic effects of mesenchymal stem cells (MSCs) derived from the bone marrow of rats (BM) against toxic effects of lead (Pb) on the male gonads of experimental rats.

METHODS

The experimental animals were exposed to lead in the form of lead nitrate (LN) one quarter of the LD50. The efficacy of MSCs to reduce gonado-totoxicity induced by lead nitrate at 21, 30 and 60 days, was evaluated experimentally in male rats.

RESULTS

The results showed that testosterone levels and semen quality ameliorated following treatment with MSCs. Also, superoxide dismutase, glutathione peroxidase and catalase levels were increased 21, 30 and 60 days post treatment of MSCs. Moreover, a decrease in genomic DNA alteration and percentage of fragmented DNA was recorded after MSCs treatment. Lead nitrate caused degeneration, necrosis, interstitial edema, and reduction in spermatogenic activity in some seminiferous tubules. The LN-induced changes in histopathologic findings of testis were partially reversed by treatment with MSCs. Histological examination of testis showed deformities in morphology of testis in test animals with gross damage within the seminiferous tubules in Lead nitrate group. The LN-induced changes in histopathologic findings of testis were partially reversed by treatment of MSCs.

CONCLUSIONS

It was concluded that lead is a gonadotoxic with a tendency of suppressing semen characteristics and testosterone levels of animals, the presence of MSCs was found to alleviate the toxic effects of lead. We conclude that MSCs derived from the bone marrow of rats can be an effective therapy of LN induced gonado toxicity, thus can contribute to the treatment of infertility.

Calcium-sensing receptor-mediated osteogenic and early-stage neurogenic differentiation in umbilical cord matrix mesenchymal stem cells from a large animal model

BACKGROUND

Umbilical cord matrix mesenchymal stem cells (UCM-MSCs) present a wide range of potential therapeutical applications. The extracellular calcium-sensing receptor (CaSR) regulates physiological and pathological processes. We investigated, in a large animal model, the involvement of CaSR in triggering osteogenic and neurogenic differentiation of two size-sieved UCM-MSC lines, by using AMG641, a novel potent research calcimimetic acting as CaSR agonist.

METHODOLOGY/PRINCIPAL FINDINGS

Large (>8 µm in diameter) and small (<8 µm) equine UCM-MSC lines were cultured in medium with high calcium (Ca2+) concentration ([Ca2+]o; 2.87 mM) and dose-response effects of AMG641 (0.01 to 3µM) on cell proliferation were evaluated. Both cell lines were then cultured in osteogenic or neurogenic differentiation medium containing: 1) low [Ca2+]o (0.37 mM); 2) high [Ca2+]o (2.87 mM); 3) AMG641 (0.05, 0.1 or 1 µM) with high [Ca2+]o and 4) the CaSR antagonist NPS2390 (10 mM for 30 min) followed by incubation with AMG641 in high [Ca2+]o. Expression of osteogenic or neurogenic differentiation biomarkers was compared among groups. In both cell lines, AMG641 dose-dependently increased cell proliferation (up to P<0.001). Osteogenic molecular markers expression was differentially regulated by AMG641, with stimulatory (OPN up-regulation) in large or inhibitory (RUNX2 and OPN down-regulation) effects in small cells, respectively. AMG641 significantly increased alkaline phosphatase activity and calcium phosphate deposition in both cell lines. Following treatment with AMG641 during osteogenic differentiation, in both cell lines CaSR expression was inversely related to that of osteogenic markers and inhibition of CaSR by NPS2390 blocked AMG641-dependent responses. Early-stage neurogenic differentiation was promoted/triggered by AMG641 in both cell lines, as Nestin and CaSR mRNA transcription up-regulation were observed.

CONCLUSIONS/SIGNIFICANCE

Calcium- and AMG641-induced CaSR stimulation promoted in vitro proliferation and osteogenic and early-stage neurogenic differentiation of UCM-MSCs. CaSR activation may play a fundamental role in selecting specific differentiation checkpoints of these two differentiation routes, as related to cell commitment status.

Cat amniotic membrane multipotent cells are nontumorigenic and are safe for use in cell transplantation

Amnion-derived mesenchymal stem cells (AMSCs) are multipotent cells with an enhanced ability to differentiate into multiple lineages. AMSCs can be acquired through noninvasive methods, and therefore are exempt from the typical ethical issues surrounding stem cell use. The objective of this study was to isolate and characterize AMSCs from a cat amniotic membrane for future application in regenerative medicine. The cat AMSCs were harvested after mechanical and enzymatic digestion of amnion. In culture medium, the cat AMSCs adhered to a plastic culture dish and displayed a fibroblast-like morphology. Immunophenotyping assays were positive for the mesenchymal stem cell-specific markers CD73 and CD90 but not the hematopoietic markers CD34, CD45, and CD79. Under appropriate conditions, the cat AMSCs differentiated into osteogenic, chondrogenic, and adipogenic cell lineages. One advantage of cat AMSCs was nonteratogenicity, assessed 4 weeks post injection of undifferentiated AMSCs into immunodeficient mice. These findings suggest that cat amniotic membranes may be an important and useful source of mesenchymal stem cells for clinical applications, especially for cell or tissue replacement in chronic and degenerative diseases.

Effects of serial passage on the characteristics and chondrogenic differentiation of canine umbilical cord matrix derived mesenchymal stem cells

Mesenchymal stem cells (MSCs) are often known to have a therapeutic potential in the cell-mediated repair for fatal or incurable diseases. In this study, canine umbilical cord MSCs (cUC-MSCs) were isolated from umbilical cord matrix (n = 3) and subjected to proliferative culture for 5 consecutive passages. The cells at each passage were characterized for multipotent MSC properties such as proliferation kinetics, expression patterns of MSC surface markers and self-renewal associated markers, and chondrogenic differentiation. In results, the proliferation of the cells as determined by the cumulative population doubling level was observed at its peak on passage 3 and stopped after passage 5, whereas cell doubling time dramatically increased after passage 4. Expression of MSC surface markers (CD44, CD54, CD61, CD80, CD90 and Flk-1), molecule (HMGA2) and pluripotent markers (sox2, nanog) associated with self-renewal was negatively correlated with the number of passages. However, MSC surface marker (CD105) and pluripotent marker (Oct3/4) decreased with increasing the number of subpassage. cUC-MSCs at passage 1 to 5 underwent chondrogenesis under specific culture conditions, but percentage of chondrogenic differentiation decreased with increasing the number of subpassage. Collectively, the present study suggested that sequential subpassage could affect multipotent properties of cUC-MSCs and needs to be addressed before clinical applications.

Immunophenotype and gene expression profile of mesenchymal stem cells derived from canine adipose tissue and bone marrow

Veterinary adult stem cell therapy is an emerging area of basic and clinical research. Like their human counterparts, veterinary mesenchymal stem cells (MSCs) offer many potential therapeutic benefits. The characterization of canine-derived MSCs, however, is poorly defined compared to human MSCs. Furthermore, little consensus exists regarding the expression of canine MSC cell surface markers. To address this issue, this study investigated characteristics of cultured canine MSCs derived from both adipose tissue and bone marrow. The canine MSCs were obtained from donors of various breeds and ages. A panel of cell surface markers for canine MSCs was selected based on current human and canine literature and the availability of canine-reactive antibodies. Using flow cytometry, canine MSCs were defined to be CD90(+)CD44(+)MHC I(+)CD14(-)CD29(-)CD34(-)MHC II(-). Canine MSCs were further characterized using real-time RT-PCR as CD105(+)CD73(+)CD14(+)CD29(+)MHC II(+)CD45(-) at the mRNA level. Among these markers, canine MSCs differed from canine peripheral blood mononuclear cells (PBMCs) by the absence of CD45 expression at the mRNA level. A novel high-throughput canine-specific PCR array was developed and used to identify changes in the gene expression profiles of canine MSCs. Genes including PTPRC, TNF, β2M, TGFβ1, and PDGFRβ, were identified as unique to canine MSCs as compared to canine PBMCs. Our findings will facilitate characterization of canine MSCs for use in research and clinical trials. Moreover, the high-throughput PCR array is a novel tool for characterizing canine MSCs isolated from different tissues and potentially from different laboratories.