In Vitro Expansion and Characterization of Mesenchymal Stromal Cells from Peritoneal Dialysis Effluent in a Human Protein Medium

Morinda officinalis saponins promote osteogenic differentiation of human umbilical cord-derived mesenchymal stem cells via the BMP-SMAD signaling pathway

BACKGROUND

Morinda officinalis saponins (MOS), a traditional Chinese medicine extracted from M. officinalis roots, have been used as a health supplement. Existing evidence suggests that extracts from this plant can be used for osteoporosis treatment. However, the molecular mechanisms underlying the anti-osteoporotic effects of M. officinalis remain poorly understood.

METHODS AND RESULTS

In this study, we investigated the osteogenesis-promoting effects of MOS on human umbilical cord-derived mesenchymal stem cells (HUC-MSCs). Alkaline phosphatase staining, alizarin red staining, and quantitative reverse transcription-PCR demonstrated that MOS promoted the osteogenic differentiation of HUC-MSCs in a concentration-dependent manner. RNA sequencing results showed that the expression of key osteogenic differentiation-related genes, including BMP4, as well as the activity of transforming growth factor-β and calcium signaling pathways increased following MOS treatment. Furthermore, treatment with the bone morphogenetic protein (BMP) antagonist Noggin reversed the MOS-induced pro-osteogenic differentiation effects and the upregulation of osteoblast-specific markers.

CONCLUSIONS

Overall, the results indicate that MOS can partially promote osteogenic differentiation of HUC-MSCs by regulating the BMP-SMAD signaling pathway. These findings indicate the potential utility of MOS as a therapeutic agent for osteoporosis, particularly in the context of stem cell therapy.

Comprehensive cell surface protein profiling of human mesenchymal stromal cells from peritoneal dialysis effluent and comparison with those from human bone marrow and adipose tissue

Peritoneal mesenchymal stromal cells (pMSCs) are isolated from peritoneal dialysis (PD) effluent, and treatment with the pMSCs reduces peritoneal membrane injury in rat model of PD. This study was designed to verify the identity of the pMSCs. pMSCs were grown in plastic dishes for 4-7 passages, and their cell surface phenotype was examined by staining with a panel of 242 antibodies. The positive stain of each target protein was determined by an increase in fluorescence intensity as compared with isotype controls in flow cytometrical analysis. Here, we showed that pMSCs predominantly expressed CD9, CD26, CD29, CD42a, CD44, CD46, CD47, CD49b, CD49c, CD49e, CD54, CD55, CD57, CD59, CD63, CD71, CD73, CD81, CD90, CD98, CD147, CD151, CD200, CD201, β2-micoglobulin, epithelial growth factor receptor, human leukocyte antigen (HLA) class 1, and, to a lesser extent, CD31, CD45RO, CD49a, CD49f, CD50, CD58, CD61, CD105, CD164, and CD166. These cells lacked expression of most hematopoietic markers such as CD11b, CD14, CD19, CD34, CD40, CD80, CD79, CD86, and HLA-DR. There was 38.55% difference in the expression of 83 surface proteins between bone marrow (BM)-derived MSCs and pMSCs, and 14.1% in the expression of 242 proteins between adipose tissue (AT)-derived MSCs and pMSCs. The BM-MSCs but not both AT-MSCs and pMSCs express cytokine receptors (IFNγR, TNFI/IIR, IL-1R, IL-4R, IL-6R, and IL-7R). In conclusion, pMSCs exhibited a typical cell surface phenotype of MSCs, which was not the same as on BM-MSCs or AT-MSCs, suggesting that the pMSCs may represent a different MSC lineage from peritoneal cavity.

Advances in stem cell therapy for peritoneal fibrosis: from mechanisms to therapeutics

Peritoneal fibrosis (PF) is a pathophysiological condition caused by a variety of pathogenic factors. The most important features of PF are mesothelial-mesenchymal transition and accumulation of activated (myo-)fibroblasts, which hinder effective treatment; thus, it is critical to identify other practical approaches. Recently, stem cell (SC) therapy has been indicated to be a potential strategy for this disease. Increasing evidence suggests that many kinds of SCs alleviate PF mainly by differentiating into mesothelial cells; secreting cytokines and extracellular vesicles; or modulating immune cells, particularly macrophages. However, there are relatively few articles summarizing research in this direction. In this review, we summarize the risk factors for PF and discuss the therapeutic roles of SCs from different sources. In addition, we outline effective approaches and potential mechanisms of SC therapy for PF. We hope that our review of articles in this area will provide further inspiration for research on the use of SCs in PF treatment.

hUC-MSCs: evaluation of acute and long-term routine toxicity testing in mice and rats

Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) are present in human umbilical connective tissue and can differentiate into various cell types. Our previous studies have proved that hUC-MSCs do not lead to allergies and tumorigenesis. In the present study, the acute and long-term toxicity of hUC-MSCs in mice and rats was evaluated. The acute toxicity of hUC-MSCs was assessed in 8-week-old mice receiving two caudal intravenous (i.v.) injections of hUC-MSCs at the maximum tolerated dose of 1.5 × 10⁷ cells/kg with an interval of 8 h and the observation period sustained for 14 days. For the long-term toxicity evaluation, rats were randomly divided into control, low-dose (3.0 × 10⁵ cells/kg), mid-dose (1.5 × 10⁶ cells/kg), and high-dose (7.5 × 10⁶ cells/kg) groups, which were treated with hUC-MSCs via a caudal i.v. injection every 3 days for 90 days. Weight and food intake evaluation was performed for all rats for 2 weeks after the hUC-MSC administration. The animals were then sacrificed for hematological, blood biochemical, and pathological analyses, as well as organ index determination. We observed no obvious acute toxicity of hUC-MSCs in mice at the maximum tolerated dose. Long-term toxicity tests in rats showed no significant differences between HUC-MSC-treated and control groups in the following parameters: body weight, hematological and blood biochemical parameters, and histopathologic changes in the heart, liver, kidneys, and lungs. This study provides evidence of the safety of i.v. hUC-MSCs infusion for future clinical therapies.

Hyaluronic Acid In Vitro Response: Viability and Proliferation Profile of Human Chondrocytes in 3D-Based Culture

OBJECTIVES

This study aimed to evaluate the efficacy of hyaluronic acid in the viability and proliferation profile of human femoral-tibial joint cartilage affected by osteoarthritis using in vitro models of chondrocytes in a 2-dimensional (2D)- and 3-dimensional (3D)-based culture model by spheroids.

DESIGN

In vitro study of knee cartilage affected by osteoarthritis that required surgical treatment. Samples were cultured and exposed to hyaluronic acid (100 and 500 μM; intervention group) or vehicle solution. In monolayer or 2D culture, proliferation and cell viability were measured, and nuclear morphometry was analyzed by 4',6'-diamino-2-fenil-indol (DAPI) staining. The 3D-based culture established from the culture of articular cartilage of patients submitted to total knee arthroplasty evaluated the diameter, viability, and fusion ability of the chondrospheres created.

RESULTS

Samples from 3 patients resulted in viable cultures, with chondrocyte cells exhibiting a potential for cell proliferation and viability to establish a culture. Hyaluronic acid (100 and 500 μM) improved chondrocyte viability and proliferation up to 72 hours in contact when compared with the control group, and no nuclear irregularities in morphology cell characteristics were observed by DAPI. In the 3D evaluation, hyaluronic acid (500 μM) improved the cellular feedback mechanisms, increasing the survival and maintenance of the chondrospheres after 7 days of analysis, showing the intrinsic capacity of chondrospheres grouped in the attempt to rearrange and reestablish new articular tissue.

CONCLUSIONS

The 2D- and 3D-based culture models with hyaluronic acid improved chondrocyte viability and proliferation and demonstrated the ability of freshly formed chondrospheres to undergo fusion when placed together in the presence of hyaluronic acid.

Comparison of mesenchymal stromal cells from peritoneal dialysis effluent with those from umbilical cords: characteristics and therapeutic effects on chronic peritoneal dialysis in uremic rats

Background

A long-term of peritoneal dialysis (PD) using a hypertonic PD solution (PDS) leads to patient’s peritoneal membrane (PM) injury, resulting in ultrafiltration failure (UFF) and PD drop-out. Our previous study shows that PD effluent-derived mesenchymal stromal cells (pMSCs) prevent the PM injury in normal rats after repeated exposure of the peritoneal cavity to a PDS. This study was designed to compare the cytoprotection between pMSCs and umbilical cord-derived MSCs (UC-MSCs) in the treatment of both PM and kidney injury in uremic rats with chronic PD.

Methods

5/6 nephrectomized (5/6Nx) Sprague Dawley rats were intraperitoneally (IP) injected Dianeal (4.25% dextrose, 10 mL/rat/day) and were treated with pMSCs or umbilical cord (UC)-MSCs (approximately 2 × 10⁶/rat/week, IP). Ultrafiltration was determined by IP injection of 30 mL of Dianeal (4.25% dextrose) with 1.5-h dewell time, and kidney failure by serum creatinine (SCr) and blood urea nitrogen (BUN). The structure of the PM and kidneys was assessed using histology. Gene expression was examined using quantitative reverse transcription PCR, and protein levels using flow cytometric and Western blot analyses.

Results

We showed a slight difference in the morphology between pMSCs and UC-MSCs in plastic dishes, and significantly higher expression levels of stemness-related genes (NANOG, OCT4, SOX2, CCNA2, RAD21, and EXO1) and MSCs surface markers (CD29, CD44, CD90 and CD105) in UC-MSCs than those in pMSCs, but no difference in the differentiation to chondrocytes, osteocytes or adipocytes. pMSC treatment was more effective than UC-MSCs in the protection of the MP and remnant kidneys in 5/6Nx rats from PDS-induced injury, which was associated with higher resistance of pMSCs than UC-MSCs to uremic toxins in culture, and more reduction of peritoneal mesothelial cell death by the secretome from pMSCs than from UC-MSCs in response to PDS exposure. The secretome from both pMSCs and UC-MSCs similarly inactivated NOS2 in activated THP1 cells.

Conclusions

As compared to UC-MSCs, pMSCs may more potently prevent PDS-induced PM and remnant kidney injury in this uremic rat model of chronic PD, suggesting that autotransplantation of ex vivo-expanded pMSCs may become a promising therapy for UFF and deterioration of remnant kidney function in PD patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02473-9.

Lung cancer-associated mesenchymal stem cells promote tumor metastasis and tumorigenesis by induction of epithelial-mesenchymal transition and stem-like reprogram

Mesenchymal stem cells (MSCs) have attracted more attention in antitumor therapy by using MSCs as vehicles or targeting modulators of MSCs. But their role and mechanisms in tumor progression are less known. In the present study, we successfully isolated pairs of MSCs from lung cancer (LC-MSCs) and adjacent tumor-free tissues. Based on the coculture system in vitro and animal studies in vivo, we originally found that LC-MSCs significantly promoted tumor metastasis and tumorigenesis both in vitro and in vivo. Partial epithelial–mesenchymal transition (EMT) was induced in lung cancer cells by LC-MSCs by the evidence of remarkable increase in snail and slug expression but not in other EMT-associated genes. The expression of stem related genes also escalated significantly. And spheroids perfectly formed when tumor cells were co-incubated with LC-MSCs. These results revealed a close link of partial EMT and acquisition of stem-like traits in lung cancer cells which was induced by LC-MSCs and greatly promoted metastasis and tumorigenesis in lung cancer. Our findings provided a new insight into LC-MSCs in tumor progression and helped to identify LC-MSCs as a potential vehicle or target for lung cancer therapy.

Protection of the Peritoneal Membrane by Peritoneal Dialysis Effluent-Derived Mesenchymal Stromal Cells in a Rat Model of Chronic Peritoneal Dialysis

Peritoneal dialysis (PD) is a renal replacement option for patients with end-stage renal disease. However, a long-term exposure to hypertonic PD solutions leads to peritoneal membrane (PM) injury, resulting in ultrafiltration (UF) failure. This study was designed to primarily evaluate efficacy of PD effluent-derived mesenchymal stromal cells (pMSCs) in the prevention of PM injury in rats. The pMSCs were isolated from PD effluent. Male Wistar rats received daily intraperitoneal (IP) injection of 10 mL of Dianeal (4.25% dextrose) and were treated with pMSCs (1.2‐1.5 × 10⁶/rat/wk, IP). UF was determined by IP injection of 30 mL of Dianeal (4.25% dextrose) with dwell time of 1.5 h, and PM injury was examined by histology. Apoptosis was quantitated by using flow cytometric analysis, and gene expression by using the PCR array and Western blot. Here, we showed that as compared to naive control, daily IP injection of the Dianeal PD solution for 6 weeks without pMSC treatment significantly reduced UF, which was associated with an increase in both PM thickness and blood vessel, while pMSC treatment prevented the UF loss and reduced PM injury and blood vessels. In vitro incubation with pMSC-conditioned medium prevented cell death in cultured human peritoneal mesothelial cells (HPMCs) and downregulated proinflammatory (i.e., CXCL6, NOS2, IL1RN, CCL5, and NR3C1) while upregulated anti-inflammatory (i.e., CCR1, CCR4, IL9, and IL-10) gene expression in activated THP1 cells. In conclusion, pMSCs prevent bioincompatible PD solution-induced PM injury and UF decline, suggesting that infusing back ex vivo-expanded pMSCs intraperitoneally may have therapeutic potential for reduction of UF failure in PD patients.