UC MSCs Research Articles

Umbilical cord mesenchymal stem cells promote the repair of trochlear groove reconstruction in dogs.

Trochlear groove reconstruction (TGR) is a common treatment for patellar luxation (PL) in dogs. Nevertheless, the prognosis of TGR is poor due to the cartilage damage and secondary inflammation. To study the repair effect of canine umbilical cord mesenchymal stem cells (UC–MSCs) after TGR, 10 experimental dogs were given TGR surgery and then randomized into two groups: Treatment group (1 ml suspension allogeneic UC–MSCs (106 cells/kg) was injected into the cavum articulare on days 0, 7, and 14 after TGR); and the Model group (injected with 1 ml of physiological saline as negative control). The therapeutic effect of UC–MSCs was studied by blood routine examination, inflammatory factor index detection, double-blind knee score, histopathology, and computed tomography (CT) scans. The results showed that the total number of white blood cells and neutrophils in the model group were significantly higher than those in the treatment group on both 7 days and 21 days, postoperatively (P < 0.05); there were no significant changes in the levels of IL-6, MMP-13, and TGF-β1 between the model group and the treatment group throughout the days of testing. The double-blind knee scores of the treatment group were significantly lower than the model group on 1st, 4th, and 5th days postoperatively (P < 0.05). The treatment group showed low-pain sensation, stable gait, and fast recovery of muscle strength in the knee score, and the wound healing of the treatment group returned to normal on the 5th day after surgery; CT scans and gross observation showed that the cartilage growth in the treatment group was faster than that in the model group. Histological observation of cases showed that fibro chondrocytes were predominantly found in the treatment group, and the distribution of chondrocytes was uneven, while the model group showed a large number of fibrous tissue hyperplasia, fissures, and unequal matrix staining. Intra-articular injection of UC–MSCs after TGR has the effect of relieving pain and promoting the repair of bone defects, making the operative limb recover function earlier, making up for the deficiency of TGR, and improving the effect of PL treatment. Future studies should furthermore explore the dose and frequency of therapy based on the multiple advantages of UC–MSCs and the mechanism of cartilage repair in dogs.

Minimal Cube Explant Provides Optimal Isolation Condition of Mesenchymal Stem Cells from Umbilical Cord.

Enzymatic digestion and explant method have been widely used for isolating umbilical cord-derived mesenchymal stem cells (UC MSCs), although there is still a strong need for robust protocols for optimal isolation for large-scale stem cell banks. This study aims to establish an explant method for clinical scale production of MSCs from human UC tissue and to characterize UC MSCs isolated and cultured with the explant method. UC MSCs were isolated by enzymatic digestion, minimal cube explant (MCE) 1-2, MCE 2-4, and MCE 10 and cultured, respectively. Also, human antibody array and basic fibroblast growth factor (bFGF) secretion in conditioned medium (CM) was analyzed. The cells were evaluated initial cell number, colony forming unit-fibroblast (CFU-F), proliferation capacity, CD marker expression, and multi-lineage differentiation. SA-β-gal assay as well as expression of p16, p21 and p53 was performed by RT-PCR. MCE 2-4 is the most optimized method for isolation of small umbilical cord-derived fast proliferating cells (smumf cells) with the greatest number. MCE 2-4 had the highest secretion of various bioactive factors including bFGF. The MCE 2-4 provided significantly higher CD146 expression than enzymatic digestion, and that expression was maintained until P20. The gene expression of p16, p21, and p53 of smumf cells did not change until P10 and SA-β-gal activity did not increase until P14. This study demonstrated that MCE 2-4 provided an optimal environment to isolate MSCs with quantity and quality from human whole UC tissue through secretion of various bioactive factors inherent to UC.

Regeneration of a full-thickness defect in rotator cuff tendon with umbilical cord-derived mesenchymal stem cells in a rat model.

Although rotator cuff disease is a common cause of shoulder pain, there is still no treatment method that could halt or reveres its development and progression. The purpose of this study was to investigate the efficacy of umbilical cord-derived mesenchymal stem cells (UC MSCs) on the regeneration of a full-thickness rotator cuff defect (FTD) in a rat model. We injected either UC MSCs or saline to the FTD and investigated macroscopic, histological and biomechanical results and cell trafficking. Treatment with UC MSCs improved macroscopic appearance in terms of tendon thickness at two weeks, and inflammation, defect size, swelling/redness and connection surrounding tissue and slidability at four weeks compared to the saline group. Histologically, UC MSCs induced the tendon matrix formation recovering collagen organization, nuclear aspect ratio and orientation angle of fibroblast as well as suppressing cartilage-related glycosaminoglycan compared to saline group at four weeks. The UC MSCs group also improved ultimate failure load by 25.0% and 19.0% and ultimate stress by 27.3% and 26.8% at two and four weeks compared to saline group. UC MSCs labeled with PKH26 exhibited 5.3% survival at four weeks compared to three hours after injection. This study demonstrated that UC MSCs regenerated the FTD with tendon tissue similar properties to the normal tendon in terms of macroscopic, histological and biomechanical characteristics in a rat model.

Regeneration of the rotator cuff tendon-to-bone interface using umbilical cord-derived mesenchymal stem cells and gradient extracellular matrix scaffolds from adipose tissue in a rat model

Regeneration of the gradient structure of the tendon-to-bone interface (TBI) is a crucial goal after rotator cuff repair. The purpose of this study was to investigate the efficacy of a biomimetic hydroxyapatite-gradient scaffold (HA-G scaffold) isolated from adipose tissue (AD) with umbilical cord derived mesenchymal stem cells (UC MSCs) on the regeneration of the structure of the TBI by analyzing the histological and biomechanical changes in a rat repair model. As a result, the HA-G scaffold had progressively increased numbers of hydroxyapatite (HA) particles from the tendon to the bone phase. After seeding UC MSCs to the scaffold, specific matrices, such as collagen, glycoaminoglycan, and calcium, were synthesized with respect to the HA density. In a rat repair model, compared to the repair group, the UC MSCs seeded HA-G scaffold group had improved collagen organization and cartilage formation by 52% at 8 weeks and 262.96% at 4 weeks respectively. Moreover, ultimate failure load also increased by 30.71% at 4 weeks in the UC MSCs seeded HA-G scaffold group compared to the repair group. Especially, the improved values were comparable to values in normal tissue. This study demonstrated that HA-G scaffold isolated from AD induced UC MSCs to form tendon, cartilage and bone matrices similar to the TBI structure according to the HA density. Furthermore, UC MSC-seeded HA-G scaffold regenerated the TBI of the rotator cuff in a rat repair model in terms of histological and biomechanical properties similar to the normal TBI.Statement of SignificanceWe found specific extracellular matrix (ECM) formation in the biomimetic-hydroxyapatite-gradient-scaffold (HA-G-scaffold) in vitro as well as improved histological and biomechanical results of repaired rotator cuff after the scaffold implantation in a rat model. This study has four strengths; An ECM scaffold derived from human adipose tissue; only one-layer used for a gradient scaffold not a multilayer used to mimic the unique structure of the gradient tendon-to-bone-interface (TBI) of the rotator cuff; UC-MSCs as a new cell source for TBI regeneration; and the UC-MSCs synthesized specific matrices with respect to the HA density without any other stimuli. This study suggested that the UC-MSC seeded HA-G-scaffold could be used as a promising strategy for the regeneration of rotator cuff tears.

Therapeutic potential of stromal cells of non-renal or renal origin in experimental chronic kidney disease

BackgroundMesenchymal stromal cell (MSC)-based therapy is a promising strategy for preventing the progression of chronic kidney disease (CKD), with the potential to induce tissue regeneration. In search of the best cellular source we compared, in the rat model of adriamycin (ADR) nephropathy, the regenerative potential of human stromal cells of non-renal origin, such as bone marrow (bm) MSCs and umbilical cord (uc) MSCs, with that of newly discovered stromal cells of renal origin, the kidney perivascular cells (kPSCs) known to exhibit tissue-specific properties.MethodsThe therapeutic effect of repeated infusions of human bmMSCs, ucMSCs, kPSCs (1.5 × 106 cells/rats) or conditioned medium from ucMSCs was studied in athymic rats with ADR-induced nephropathy (7.9 mg/kg). The ability of the three stromal cell populations to engraft the damaged kidney was evaluated by detecting the presence of human nuclear antigenpos cells. Glomerular podocyte loss and endothelial damage, sclerotic lesions and inflammation were assessed at 14 and 28 days. In-vitro experiments with a transwell system were performed to investigate the effects of different stromal cell populations on parietal epithelial cells (PECs) activated or not with albumin or angiotensin II for 24 h.ResultsInfusions of non-renal and renal stromal cells resulted in a comparable engraftment into the kidney, in the peritubular areas and around the glomerular structures. All three cell populations limited podocyte loss and glomerular endothelial cell injury, and attenuated the formation of podocyte and PEC bridges. This translated into a reduction of glomerulosclerosis and fibrosis. Human ucMSCs had an anti-inflammatory effect superior to that of the other stromal cells, reducing macrophage infiltration and inducing polarisation towards the M2 macrophage phenotype. Conditioned medium from ucMSCs shared the same renoprotective effects of the cells. Consistent with in-vivo data, bmMSCs and kPSCs, but even more so ucMSCs, limited proliferation, migratory potential and extracellular matrix production of activated PECs, when cultured in a transwell system.ConclusionsOur data indicate that either non-renal or renal stromal cells induce renal tissue repair, highlighting ucMSCs and their conditioned medium as the most reliable clinical therapeutic tool for CKD patients.

Maternal obesity impairs skeletal development in adult offspring

Intrauterine or early postnatal high-fat diet (HFD) has substantial influences on adult offspring health; however, studies of HFD-induced maternal obesity on regulation of adult offspring bone formation are sparse. Here, we investigated the effects of HFD-induced maternal obesity on both fetal and adult offspring skeletal development. We found that HFD-induced maternal obesity significantly decreased fetal skeletal development, but enhanced fetal osteoblastic cell senescence signaling and significantly increased the expression of inflammatory factors of the senescence-associated secretory phenotype (SASP) in osteo-progenitors. It was found that p300/CBP activation led to H3K27 acetylation to increase the expression of senescence-related genes and PPARγ in embryonic mouse osteogenic calvarial cells from HFD obese dams. These results were recapitulated in human umbilical cord mesenchymal stem cells (UC MSCs) isolated from offspring of pregnant obese and lean mothers following delivery. Regardless of postnatal HFD challenge, adult offspring from HFD obese dams showed significantly suppressed bone formation. Such early involution of bone formation of adult offspring from HFD obese dams may at least in part due to histone acetylation, i.e., epigenetic regulation of genes involved in cell senescence signaling in pre-osteoblasts from prenatal development. These findings indicate fetal pre-osteoblastic cell senescence signaling is epigenetically regulated by maternal obesity to repress bone formation in adult offspring in rodents and suggest that at least some of these effects may also manifest in humans.

Long-term safety of umbilical cord mesenchymal stem cells transplantation for systemic lupus erythematosus: a 6-year follow-up study.

The aim of this study is to assess the long-term safety of allogeneic umbilical cord mesenchymal stem cells (UC MSCs) transplantation for patients with refractory systemic lupus erythematosus (SLE). Nine SLE patients, who were refractory to steroid and immunosuppressive drugs treatment and underwent MSCs transplantation in 2009, were enrolled. One million allogeneic UC MSCs per kilogram of body weight were infused intravenously at days 0 and 7. The possible adverse events, including immediately after MSCs infusions, as well as the long-term safety profiles were observed. Blood and urine routine test, liver function, electrocardiogram, chest radiography and serum levels of tumor markers, including alpha fetal protein (AFP), cancer embryo antigen (CEA), carbohydrate antigen 155 (CA155) and CA199, were assayed before and 1, 2, 4 and 6 years after MSCs transplantation. All the patients completed two times of MSCs infusions. One patient had mild dizzy and warm sensation 5min after MSCs infusion, and the symptoms disappeared quickly. No other adverse event, including fluster, headache, nausea or vomit, was observed. There was no change in peripheral white blood cell count, red blood cell count and platelet number in these patients after followed up for 6years. Liver functional analysis showed that serum alanine aminotransferase, glutamic-oxalacetic transaminase, total bilirubin and direct bilirubin remained in normal range after MSCs infusions. No newly onset abnormality was detected on electrocardiogram and chest radiography. Moreover, we found no rise of serum tumor markers, including AFP, CEA, CA125 and CA199, before and 6years after MSCs infusions. Our long-term observational study demonstrated a good safety profile of allogeneic UC MSCs in SLE patients.

Alternative Xeno-Free Biomaterials Derived from Human Umbilical Cord for the Self-Renewal Ex-vivo Expansion of Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are attractive candidates for novel cell-therapy applications. However, the in vitro expansion of MSCs typically depends on the presence of fetal bovine serum (FBS) and coating materials derived from animal sources, which may cause contamination in clinical applications. In this study, we investigated whether human umbilical cord extract (UCE) could serve as a serum replacement and whether collagen purified from umbilical cord (UC-collagen) could act as an extracellular matrix (ECM) for the in vitro culture of MSCs derived from human UC (UC-MSCs). A total of 5.61 ± 0.54 mg UCE and 18.41 ± 2.42 mg collagen were extracted, and 1.3 ± 0.2 × 10⁵ cells were isolated from 1 g of UC, as determined by the expression of typical MSC surface markers. Importantly, the proliferation and stemness of the UC-MSCs cultured with the UCE media were similar to those cultured under FBS conditions on UC-collagen-treated plates for eight passages. Based on these results, we suggest that UCs, which are discarded as medical waste, represent a viable alternative source of xeno-free biomaterials to replace animal-derived serum and ECM materials for the cultivation of various cell types, including UC-MSCs, adipose tissue-derived MSCs, bone marrow-derived MSCs, and fibroblasts. This innovative xeno-free MSCs culture system can overcome many of the problems associated with immunogenicity, and it will further contribute to the enhancement of treatment efficiency.