Bozorgmehr et al. Endometrial and Menstrual Blood MSC and MenSC to ensure these protocols produce cell products free from tumorigenicity and toxicity. Although a wealth of data on the biological properties of eMSC and MenSC has recently been published, it will be important to address their mechanism of action in preclinical models of human disease.

Background: There is significant interest in using nanofibers in tissue engineering from stem cells. The transdifferentiation of mesenchymal stem cells into the hepatic lineage in a nanofibrous structure has not been reported. In this study, a three dimensional nanofibrous scaffold is introduced for differentiation of human bone marrow derived mesenchymal stem cells (hBMSCs) into hepatocytes. Methods: A scaffold composed of Poly (e-caprolactone), collagen and polyethersulfone was fabricated by the electrospinning technique. After characterization of isolated hBMSCs, the performance of the cells on the scaffold was evaluated by Scanning Electron Microscopy (SEM) and MTT assay. Cytological, molecular and biochemical markers were measured to confirm differentiation potential of hBMSCs into hepatocytes. Results: The isolated cells possessed the basic properties of mesenchymal stem cells (MSCs). Based on scanning electron microscope (SEM) analysis and MTT assay, it was shown that the cells adhere, penetrate and proliferate on the nanofibers. Cultured cells on the nanofibers differentiated into hepatocyte-like cells and expressed hepatocyte specific markers such as albumin, a-fetoprotein, cytokeratin-18, cytokeratin-19 and cytochrome P450 3A4 at mRNA levels. Appearance of a considerable number of albumin-positive cells cultivated on the scaffold (47 Ϯ 4%) as compared to the two-dimensional culture system (28 Ϯ 6%) indicates the supporting role of the scaffold. The efficiency of the cells to produce albumin, urea, transferrin, serum glutamic pyruvic transaminase and serum oxaloacetate aminotransferase in hepatocytes on the scaffold further attest to the functionality of the cells. Conclusion:The data presented in this study show that the engineered nanofibrous scaffold is a conductive matrix which supports and enhances MSC development into functional hepatocyte-like cells.

In recent decades, stem cell therapy has been introduced as a novel therapeutic approach for patients suffering from bone disorders. Recently, menstrual blood has been identified as an easily accessible and recycled stem cell source. However, the osteogenic differentiation capacity of menstrual blood-derived stem cells (MenSCs) compared with other adult stem cells remained unsolved. The aim of this study was to investigate the osteogenic differentiation capacity of MenSCs compared to bone marrow-derived mesenchymal stem cells (BMSCs) in the presence of human platelet releasate (HPR). Our results showed that MenSCs were strongly positive for mesenchymal and negative for hematopoietic stem cell markers in a similar manner to BMSCs. In contrary to BMSCs, MenSCs exhibited marked expression of OCT-4 and a significantly higher proliferative capacity. Mineralization, as judged by alizarin red staining, was more pronounced in differentiated BMSCs than in differentiated MenSCs in an osteogenic medium fortified with fetal bovine serum (FBS). However, FBS substitution with HPR in a differentiation medium resulted in typical impact on intensity of MenSC mineralization. The results of semiquantitative reverse transcription-polymerase chain reaction showed comparable levels of parathyroid hormone receptor and osteocalcin transcripts in both types of differentiated stem cells in an HPR medium supplemented with osteogenic inducers. However, the upregulation level of alkaline phosphatase was relatively lower in differentiated MenSCs than that in differentiated BMSCs. We concluded that despite lower osteogenic differentiation capacity of MenSCs compared to BMSCs, substitution of FBS with HPR could equalize the osteogenic differentiation of MenSCs. Therefore, by taking advantage of osteogenic driving potential of HPR, MenSCs could be introduced as an apt and safe alternative to BMSCs for bone tissue-engineering purposes.

Background Cell-free Mesenchymal stromal cells (MSCs) have been considered due to their capacity to modulate the immune system and suppress cytokine storms caused by SARS-CoV-2. This prospective randomized double-blind placebo-controlled clinical trial aimed to assess the safety and efficacy of secretome derived from allogeneic menstrual blood stromal cells (MenSCs) as a treatment in patients with severe COVID-19. Methods Patients with severe COVID-19 were randomized (1:1) to either MenSC-derived secretome treatment or the control group. Subjects received five intravenous infusions of 5 mL secretome or the same volume of placebo for five days and were monitored for safety and efficacy for 28 days after treatment. Adverse events, laboratory parameters, duration of hospitalization, clinical symptom improvement, dynamic of O2 saturation, lymphocyte number, and serial chest imaging were analyzed. Results All safety endpoints were observed without adverse events after 72 h of secretome injection. Within 28 days after enrollment, 7 patients (50%) were intubated in the treated group versus 12 patients (80%) in the control group. Overall, 64% of patients had improved oxygen levels within 5 days of starting treatment (P < 0.0001) and there was a survival rate of 57% in the treatment group compared to 28% in the control group was (P < 0.0001). Laboratory values revealed that significant acute phase reactants declined, with mean C-reactive protein, ferritin, and D-dimer reduction of 77% (P < 0.001), 43% (P < 0.001), and 42% (P < 0.05), respectively. Significant improvement in lymphopenia was associated with an increase in mean CD4+ and CD8+ lymphocyte counts of 20% (P = 0.06) and 15% (P < 0.05), respectively. Following treatment, percentage of pulmonary involvement showed a significant improvement in the secretome group (P < 0.0001). This improvement differed significantly between survivors and those who were dying (P < 0.005). Conclusions For the first time, this study demonstrated that in hospitalized patients with severe COVID-19, therapy with MenSCs-derived secretome leads to reversal of hypoxia, immune reconstitution, and downregulation of cytokine storm, with no adverse effects attributable to the treatment. Given these outcomes, it may be possible to use this type of treatment for serious inflammatory lung disease with a mechanism similar to COVID-19 in the future. However, it is necessary to evaluate the safety and efficacy of MenSCs-derived secretome therapy in clinical trials on a larger population of patients. Trial registration: ClinicalTrials.gov Identifier: NCT05019287. Registered 24AGUEST 2021, retrospectively registered, https://clinicaltrials.gov/ct2/show/record/NCT05019287. IRCT, IRCT20180619040147N6. Registered 04/01/2021.

Menstrual blood has been introduced as an easily accessible and refreshing stem cell source with no ethical consideration. Although recent works have shown that menstrual blood stem cells (MenSCs) possess multi lineage differentiation capacity, their efficiency of hepatic differentiation in comparison to other stem cell resources has not been addressed so far. The aim of this study was to investigate hepatic differentiation capacity of MenSCs compared to bone marrow-derived stem cells (BMSCs) under protocols developed by different concentrations of hepatocyte growth factor (HGF) and oncostatin M (OSM) in combination with other components in serum supplemented or serum-free culture media. Such comparison was made after assessment of immunophenotye, trans-differentiation potential, immunogenicity and tumorigeicity of these cell types. The differential expression of mature hepatocyte markers such as albumin (ALB), cytokeratin 18 (CK-18), tyrosine aminotransferase and cholesterol 7 alpha-hydroxylase activities (CYP7A1) at both mRNA and protein levels in differentiating MenSCs was significantly higher in upper concentration of HGF and OSM (P1) compared to lower concentration of these factors (P2). Moreover, omission of serum during differentiation process (P3) caused typical improvement in functions assigned to hepatocytes in differentiated MenSCs. While up-regulation level of ALB and CYP7A1 was higher in differentiated MenSCs compared to driven BMSCs, expression level of CK-18, detected level of produced ALB and glycogen accumulation were lower or not significantly different. Therefore, based on the overall comparable hepatic differentiation ability of MenSCs with BMSCs, and also accessibility, refreshing nature and lack of ethical issues of MenSCs, these cells could be suggested as an apt and safe alternative to BMSCs for future stem cell therapy of chronic liver diseases.

In this study characterization of endothelial cells differentiated from human bone marrow mesenchymal stem cells (hBMCs) was investigated in relation to their capillary network formation potential. Differentiation was performed in presence of vascular endothelial growth factor (VEGF) and insulin like growth factor-1 (IGF-1). A panel of cellular and molecular markers was used for characterization of the endothelial cells. The cells were strongly positive for von Willebrand factor (vWF) and vascular endothelial growth factor receptor 2 (VEGFR2) when measured at protein and mRNA levels. Development of endothelial cells was found to be associated with formation of typical organelles such as Weibel Palade (WP) bodies, Cavealae and pinocytic vesicles. Early vessel growth was also evidenced by showing specific junctions between the cells. The migratory and angiogenic properties of the cells were confirmed by showing capillary network formation in vitro. These results indicate that the capacity of endothelial cells differentiated from hBMSCs in formation of vascular system is consistent with molecular and structural development.

The evidence presented in this study introduces MenSCs as a suitable stem cell population candidate for cartilage tissue engineering.

Presented data suggest an efficient differentiation protocol for in vitro production of MenSC-derived adipocytes. These cells are suggested to be an apt alternative to BMSCs for future stem cell therapy of soft tissue injuries.