A Simple High Yield Technique for Isolation of Wharton's Jelly-derived Mesenchymal Stem Cell.

Background: The isolation of Mesenchymal Stem Cells (MSCs) from various tissues is possible, with the umbilical cord emerging as a competitive alternative to bone marrow. In order to fulfill the demands of cell therapy, it is essential to generate stem cells on a clinical scale while minimizing time, cost, and contamination. Here is a simple and effective protocol for isolating MSC from Wharton's Jelly (WJ-MSC) using the explant method with various supplements. Methods: Utilizing the explant method, small fragments of Wharton's jelly from the human umbilical cord were cultured in a flask. The multipotency of the isolated cells, were confirmed by their differentiation ability to osteocyte and adipocyte. Additionally, the immunophenotyping of WJ-MSCs showed positive expression of CD73, CD90, and CD105, while remaining negative for hematopoietic markers CD34 and CD45, meeting the criteria for WJ-MSC identification. Following that, to evaluate cells' proliferative capacity, various supplements, including basic Fibroblast Growth Factor (bFGF), Non-Essential amino acids (NEA), and L-Glutamine (L-Gln) were added to either alpha-Minimal Essential Medium (α-MEM) or Dulbecco's Modified Eagle's Medium-F12 (DMEM-F12), as the basic culture media. Results: WJ-MSCs isolated by the explant method were removed from the tissue after seven days and transferred to the culture medium. These cells differentiated into adipocyte and osteocyte lineages, expressing CD73, CD90, and CD105 positively and CD34 and CD45 negatively. The results revealed that addition of bFGF to α-MEM or DMEMF12 media significantly increased the proliferation of MSCs when compared to the control group. However, there were no significant differences observed when NEA or LGln were added. Conclusion: Although bFGF considerably enhances cell proliferation, our study demonstrates that MSCs can grow and expand when properly prepared Wharton's jelly tissues of the human umbilical cord.

Exosomes Derived from Heat-shocked Tumor Cells Promote In vitro Maturation of Bone Marrow-derived Dendritic Cells.

Dendritic cells (DCs), professional antigen-presenting cells that process and deliver antigens using MHC II/I molecules, can be enhanced in numerous ways.  Exosomes derived from heat-shocked tumor cells (HS-TEXs) contain high amounts of heat-shock proteins (HSPs). HSPs, as chaperons, can induce DC maturation. This study aimed to investigate whether HS-TEXs can promote DC maturation. To generate DC, bone marrow-derived cells were treated with Interleukin-4 and GM-CSF. Exosomes were isolated from heat-treated CT-26 cells. The expression level of HSP in exosomes was checked by western blot and the increase in the expression of this protein was observed. Then, HS-TEXs were co-cultured with iDCs to determine DC maturity, and then DCs were co-cultured with lymphocytes to determine DC activity. Our results showed that  DCs treated with HS-TEXs express high levels of molecules involved in DC maturation and function including MHCII, CD40, CD83, and CD86. HS-TEXs caused phenotypic and functional maturation of DCs. In addition, flow cytometric results reflected a higher proliferative response of lymphocytes in the iDC / Tex + HSP group. HS-TEXs could be used as a strategy to improve DC maturation and activation.

Human Wharton's jelly mesenchymal stem cells derived-exosomes enriched by miR-124 promote an anti-fibrotic response in an experimental model of liver fibrosis.

BACKGROUND: Liver fibrosis is a significant challenge to global health that results in organ failure through inflammation and the release of fibrotic biomarkers. Due to the lack of effective treatments for liver fibrosis, anti-fibrotic and anti-inflammatory therapies are being developed. Since there has been an association between aberrant expression of miR-124 and liver disease progression, we investigated whether delivery of miR-124 through human Wharton's jelly mesenchymal stem cells derived-exosomes (hWJMSC-Exo) can improve liver fibrosis. METHODS: We established a 6-week carbon tetrachloride (CCl4)-induced mouse model of liver fibrosis, then we administered hWJMSC-Exo and miR-124-3p-enriched exosomes (ExomiR-124) for three weeks. The extent of fibrosis and inflammation was assessed by histology, biochemistry, Real-time PCR, immunohistochemistry, and Enzyme-linked immunoassays (ELISA). The inflammatory status of the spleen was also investigated using flow cytometry. RESULTS: Based on the gene and protein expression measurement of IL-6, IL-17, TGF-ß, STAT3, α-SMA, and COL1, In vivo administration of Exo and ExomiR-124 effectively reduce collagen accumulation and inhibition of inflammation. Regarding histopathology findings, the therapeutic effect of ExomiR-124 against liver fibrosis was significantly greater than hWJMSC-Exo. In addition, we found that Exo and ExomiR-124 was capable of phenotype switching of splenic monocytes from inflammatory Ly6Chi to restorative Ly6Clo. CONCLUSIONS: MSC-derived exosomes demonstrated anti-inflammatory effect via different aspects. Aside from the therapeutic approach, enrichment of exosomes as a nanocarrier by miR-124 revealed the down-regulation of STAT3, which plays a crucial role in liver fibrosis. The anti-inflammatory and anti-fibrotic properties of ExomiR-124 could be a promising option in liver fibrosis combination therapies.

Oleuropein reduces LPS-induced inflammation via stimulating M2 macrophage polarization.

Oleuropein (OLEU) is the most prevalent phenolic component in olive varieties, and it has been considered for its powerful antioxidant properties in therapeutic applications. OLEU has anti-inflammatory properties and performs this property by suppressing inflammatory cells' function and reducing oxidative stress caused by various factors. This study investigated the ability of OLEU to polarize LPS-stimulated murine macrophage (MQ) cell RAW 264.7 into M1/M2 macrophages. As a first step, the cytotoxicity effects of OLEU were evaluated on LPS-stimulated RAW 264.7 cells using the thiazolyl blue (MTT) colorimetric test. Then, cytokines production, gene expression (Real-Time PCR), and functions (Nitrite oxide assay and phagocytosis assay) of OLEU-treated LPS-stimulated RAW 264.7 cells were evaluated. Our findings demonstrated that OLEU could reduce nitrite oxide (NO) production in LPS-stimulated RAW 264.7 cells by downregulating the inducible nitric oxide synthase gene expression. Furthermore, OLEU therapy decreases the expression of M1-associated pro-inflammatory cytokines production (IL-12, IFN-γ, and TNF-α) and genes expression (iNOS, TNF-α) while increasing the M2-associated anti-inflammatory gene expression and cytokines production (IL-10, and TGF-ß). Based on the result, OLEU may be considered a potential therapeutic approach for inflammatory diseases due to its possible effects on oxidative stress-related factors, cytokine expression and production, and phagocytosis.

Engineering tumor-derived small extra cellular vesicles to encapsulate miR-34a, effectively inhibits 4T1 cell proliferation, migration, and gene expression.

Tumor cells produce small extra cellular vesicles-(tsEV) massively, which act as cancer messengers that may also have anti-cancer effects. Based on this knowledge, we hypothesized that we can benefit from 4T1-derived sEVs to amplify the anti-cancer effects of miR-34a-replacement therapy in 4T1 cells. Supernatant of 4T1 cultured cells gathered after 24 h of exposure to serum-free media. tsEVs purified by commercial kit and characterized by transmission and scanning electron microscopy, dynamic light scattering, and bicinchoninic acid assay. Modified CaCl2 method applied for miR-34a loading in tsEV (tsEV-miR) and loading confirmation evaluated by the relative expression of miR-34a. MTT, annexin V/PI, cell cycle, scratch test, and real-time PCR were performed for proliferation, apoptosis, invasion, and relative expression of miR-34a target genes after treatment with tsEV/tsEV-miR, respectively. The results indicated that tsEV-miR provides a time-dose-dependent anti-proliferative effect versus tsEV/control group. tsEV-miR could induce apoptosis and arrest the cell cycle at G0/G1 phase, and moreover, it effectively halted the invasion capability of 4T1 cells. Treatment with tsEV-miR down-regulated miR-34a target genes, including B-cell lymphoma-2, vascular endothelial growth factor and its receptor, matrix metalloproteinase-2 and -9, and interleukin-6. Engineered tsEVs can affect different aspects of 4T1 cancer cells including proliferation, apoptosis, cell cycle, migration, and cancer-related gene expression profile. In this regard, tsEV could be considered a proper vehicle for miR-34a replacement therapy and could exacerbate its anti-cancer effects in triple-negative breast cancer. Indeed, TNBC can be targeted by multiple angles by its weapon.

Immunomodulatory and protective effects of adipose tissue-derived mesenchymal stem cells in an allograft islet composite transplantation for experimental autoimmune type 1 diabetes.

BACKGROUND: Allogeneic islet transplantation could be an ideal alternative therapy for Type 1 Diabetes Mellitus (T1DM). Adipose Tissue-derived Mesenchymal Stem Cells (AT-MSCs) characterized by immunomodulatory and protective effects may have the potential to improve the outcome of this highly immunogenic transplant. METHODS: Syngenic AT-MSCs along with allograft islets embedded in hydrogelic composite and transplanted intraperitoneally in Streptozotocin (STZ) induced diabetic C57BL/6 mice. RESULTS: In vitro experiments of co-imbedded islets and AT-MSCs in a hydrogel revealed AT-MSCs are able to significantly increase insulin secretion. During a 32 days of post-transplant period, blood glucose monitoring showed a decrease from over 400mg/dl to less than 150mg/dl and at the end of 32 days, mice have been dissected and assessed. Graft histopathology demonstrated that hydrogel makes an artificial immune isolation site and AT-MSCs contribute greatly to the reduction of the immune cells infiltration. Analyses of mononuclear cells isolated from Mesenteric Lymph Nodes (MLNs) and spleen showed that AT-MSCs co-transplanted with allograft decreased pro-inflammatory cytokines and increased regulatory cytokines (for both MLNs and spleen) and regulatory T cells (Treg) population (only for MLNs). In addition, real time-PCR assays revealed that transcript levels of IDO, iNOS, and PDX1, significantly increased in allograft islets in the presence of AT-MSCs. CONCLUSIONS: according to results, this investigation indicates that AT-MSCs can be regarded as promising complementary candidates for engineered-cell therapy using hydrogel composites in islet transplantation.