Development and investigational new drug application of mesenchymal stem/stromal cells products in China.

Mesenchymal stem/stromal cells (MSCs) have broad application prospects for regenerative medicine due to their self-renewal, high plasticity, ability for differentiation, and immune response and modulation. Interest in turning MSCs into clinical applications has never been higher than at present. Many biotech companies have invested great effort from development of clinical grade MSC product to investigational new drug (IND) enabling studies.

The Promise of Mesenchymal Stem Cells Therapy for Acute Respiratory Distress Syndrome Caused by COVID-19.

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) since Dec 2019, known as COVID-19 or 19-nCoV, has led to a major concern of the potential for not only an epidemic but a pandemic in China and now it seems to be a public health problem all over the world. The general mortality rate of the COVID-19 was about 3%. However, the mortality risk seems to be a significant increase in elderly and cases with chronic disease, who are more likely to develop into acute respiratory distress syndrome (ARDS).

Systematic comparison of hUC-MSCs at various passages reveals the variations of signatures and therapeutic effect on acute graft-versus-host disease.

Background: Mesenchymal stem cells are heterogenous populations with hematopoietic supporting and immunomodulating capacities. Enormous studies have focused on their preclinical or clinical therapeutic effects, yet the systematic study of continuous in vitro passages on signatures and functions of UC-MSCs at both the cellular and molecular levels is still lacking.

Methods: In this study, to systematically evaluate the biological properties of MSCs at various passages, we analyzed biomarker expression, cell proliferation and apoptosis, chromosome karyotype, and tri-lineage differentiation potential.

Comparison of Teratoma Formation between Embryonic Stem Cells and Parthenogenetic Embryonic Stem Cells by Molecular Imaging.

With their properties of self-renewal and differentiation, embryonic stem (ES) cells hold great promises for regenerative therapy. However, teratoma formation and ethical concerns of ES cells may restrict their potential clinical applications. Currently, parthenogenetic embryonic stem (pES) cells have attracted the interest of researchers for its self-renewing and pluripotent differentiation while eliciting less ethic concerns.

VE-Cadherin regulates the self-renewal of mouse embryonic stem cells via LIF/Stat3 signaling pathway.

With the abilities of self-renewal and differentiation, embryonic stem (ES) cells provide an unlimited source for stem cell-based therapeutics. However, the maintenance of ES cells with mouse embryonic fibroblasts (MEFs) can limit the clinical translation of ES cells. In the present study, we synthesized a fusion protein of the immunoglobulin G (IgG) fragment crystallizable region and vascular endothelial cadherin (VE-cadherin) extracellular domain (VE-cad-Fc) as a substrate for mouse ES cell culture, and we hypothesized that VE-cadherin could enhance the pluripotency and self-renewal of ES cells.

Aberrant expression and significance of OCT-4A transcription factor in leukemia cells.

Objective: To determine the contribution of the OCT-4 to the pathogenesis of leukemia.

Methods: Bone marrow (BM) samples obtained from 72 patients with leukemia, and 18 normal healthy subjects were assayed for their OCT-4 expression using both flow cytometry and RT-PCR.

Results: OCT-4 expression in BM nucleated cells of acute leukemia patients (n=33) was significantly higher than that of complete remission and chronic phase leukemia patients (n=39, p<0.

Expression and role of Toll-like receptors on human umbilical cord mesenchymal stromal cells.

Background Aims: Toll-like receptors (TLRs) play an important role in innate and adaptive immunity by recognizing pathogen-associated molecular patterns (PAMPs).

Methods: In the present study, we investigated the expression and role of TLRs on human umbilical cord mesenchymal stromal cells (UC-MSCs). The proliferation, differentiation and immunoregulatory activity of UC-MSCs primed with or without TLR ligands were determined.

Bone marrow-derived cells can acquire renal stem cells properties and ameliorate ischemia-reperfusion induced acute renal injury.

Background: Bone marrow (BM) stem cells have been reported to contribute to tissue repair after kidney injury model. However, there is no direct evidence so far that BM cells can trans-differentiate into renal stem cells.

Methods: To investigate whether BM stem cells contribute to repopulate the renal stem cell pool, we transplanted BM cells from transgenic mice, expressing enhanced green fluorescent protein (EGFP) into wild-type irradiated recipients.

Establishment of a new method to induce the differentiation of embryonic pancreatic cells into mature endocrine cells.

Objective: To establish a new culture method to induce the differentiation of embryonic pancreatic cells into mature endocrine cells.

Methods: Mouse embryos at day 12.5 were used and embryonic pancreata were isolated.

Impaired immunomodulatory ability of bone marrow mesenchymal stem cells on CD4(+) T cells in aplastic anemia.

Aplastic anemia (AA) is a marrow failure syndrome mediated by aberrant T-cell subsets. Mesenchymal stem cells (MSCs) play an important role in maintaining immune homeostasis through modulating a variety of immune cells. However, little is known about the immunomodulation potential of bone marrow MSCs (BM-MSCs) in AA.

CD72 gene expression in immune thrombocytopenia.

To explore the role of CD72 in the pathogenesis of immune thrombocytopenia (ITP), we detected CD72, Sema4D, IL-2, IL-4, and IFN-γ mRNA expressions and the levels of plasma Sema4D, IL-2, IL-4, IL-6, and IFN-γ in ITP patients (n = 39) and controls (n = 23). The levels of plasma IL-2, IL-4, and IL-6 were assayed by radioimmunoassay, and the levels of plasma IFN-γ and Sema4D were analyzed by enzyme-linked immunosorbent assay. Sema4D, CD72, IL-2, IFN-γ, and IL-4mRNA expressions were analyzed by real-time quantitative reverse-transcription polymerase chain reaction.

[Umbilical cord mesenchymal stem cell transplantation for treatment of experimental autoimmune myasthenia gravis in rats].

Umbilical cord mesenchymal stem cell (UCMSC) transplantation has been widely used in the treatment of a variety of diseases due to their advantages such as abundant resources, low immunogenicity and large ex vivo expansion capacity. This study was aimed to investigate the effects of UCMSC on experimental autoimmune myasthenia gravis (EAMG) rats. The distribution of human-derived cells was observed by immunofluorescence method, the effect of MSC on B-cell in situ-secreted antibodies was assayed by ELISPOT, the secreted IFN-γ level was detected by using Transwell test.

[Isolation of mesenchymal stem cells from bone marrow filters by primary explant culture].

This study was aimed to investigate whether mesenchymal stem cells (MSC) can be isolated from bone marrow filters which have always been discarded. The bone marrow (BM) particles from BM filters of 2 healthy donors were cultivated by primary explant culture. After expansion, the number of MSC was counted and their immunophenotype and differentiation potential were detected.

Interleukin-27 enhances the production of tumour necrosis factor-α and interferon-γ by bone marrow T lymphocytes in aplastic anaemia.

Aplastic anaemia (AA) is considered as an immune-mediated bone marrow failure syndrome. The mechanism is involved with a variety of immune molecules including interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α) and interleukins (ILs). IL-27 is a novel member of the IL-12 family, which mediates T cell response and enhances the production of IFN-γ.

More mesenchymal stem cells enriched from bone marrow aspirates by culturing bone marrow particles and mononuclear cells separately.

Bone marrow (BM) is the major source of mesenchymal stem cells (MSC). In most experiments, MSC were classically cultured from mononuclear cells (MNC) isolated by density gradient centrifugation method. However, several studies have demonstrated that this method was less efficient for MSC recovery.

[Enhancement of all-trans retinoic acid induced HL-60 leukemia cell differentiation by human umbilical cord mesenchymal stem cells].

This study was aimed to investigate the enhancement of all-trans retinoic acid-induced HL-60 leukemia cell differentiation by human umbilical cord mesenchymal stem cells (hucMSC). The HL-60 cells were divided into 4 groups: control group (HL-60 cells treated without ATRA), hucMSC group (HL-60 cells co-cultured with hucMSCs), ATRA group (HL-60 cells treated with ATRA) and ATRA + hucMSC group (HL-60 cells treated with ATRA and co-cultured with hucMSCs). The proliferations of control group and hucMSC group were compared by Cell Counting Kit-8 (CCK8).

[Differentiation of human umbilical cord derived mesenchymal stem cells into low immunogenic and functional hepatocyte-like cells in vitro].

Objective: To investigate the biological function of hepatocyte-like cells derived from mesenchymal stem cells that isolated from human umbilical cord UC-MSCs in vitro, and to detect the changes in the immunogenicity of the differentiated hepatocyte-like cells (DHC).

Methods: Transdifferentiation of UC-MSCs into hepatic lineage in vitro was induced in modified two-step induction medium. The expressions of hepatic specific markers were detected by RT-PCR analysis and immunofluorescence staining at different time points after induction.

[IL-27 regulates the expression of Mac-1, fMLP-R and IL-1beta in human neutrophils through p38 MAPK and PI3K signal pathways].

The present study was aimed to investigate the pathways, by which IL-27 regulates the expression of adherent molecule Mac-1, chemotactic factor receptor fMLP-R and pro-inflammatory cytokine IL-1beta in human neutrophils. Highly purified human neutrophils were isolated from peripheral blood using Ficoll-Hypaque gradients centrifugation and erythrocyte lysis. The mRNA expression of IL-27 receptor components (WSX-1/TCCR and gp130) in human neutrophils was detected by reverse transcription polymerase chain reaction (RT-PCR).

No contribution of umbilical cord mesenchymal stromal cells to capillarization and venularization of hepatic sinusoids accompanied by hepatic differentiation in carbon tetrachloride-induced mouse liver fibrosis.

Background Aims: The acceleration of capillarization and venularization of hepatic sinusoids after cell therapy would not be beneficial to restoration after liver disease. The goal was to observe the effects of umbilical cord (UC)-derived mesenchymal stromal cells (MSC) on liver microcirculation and their therapeutic potential in liver fibrosis.

Methods: Human UC MSC labeled with or without CM-DIL were transplanted into NOD/SCID mice with carbon tetrachloride (CCl4)-induced chronic liver fibrosis models.

[Effect of fetal lung mesenchymal stem cells on differentiation of umbilical cord blood mononuclear cells into megakaryocytes].

In order to analysis the effect of fetal lung mesenchymal stem cell (FL-MSC) on differentiation of umbilical cord blood mononuclear cells (MNC) into megakaryocytes, the fresh umbilical cord blood MNC were isolated and divided into 2 groups in the culture added with TPO, IL-11 and heparin. In the first group MNC were cultured alone and in the second group MNC were cocultured with FL-MSC. The cells were collected at day 7, 10, 14 for cell counting and detection of CD41a and CD61 by flow cytometry.

Raised expression of APRIL in Chinese patients with immune thrombocytopenia and its clinical implications.

Background: Immune thrombocytopenia (ITP) is an immune-mediated disorder in which destruction of platelets is accelerated by anti-platelet autoimmune antibodies. B-cell-activating factor (BAFF) and a proliferation-inducing ligand (APRIL), essential factors for B cell survival are elevated in systemic autoimmune diseases and correlated with clinical findings. High expression of BAFF has been shown in patients with ITP, but the status of APRIL in ITP is still unknown.

Stem/progenitor cells in liver injury repair and regeneration.

Morbidity and mortality from cirrhosis is increasing rapidly in the world. Currently, orthotopic liver transplantation is the only definitive therapeutic option. However, its clinical use is limited, because of poor long-term graft survival, donor organ shortage and high costs associated with the procedure.

Suppression of ABCG2 inhibits cancer cell proliferation.

The ATP-binding cassette efflux transporter, ABCG2, is widely expressed in a variety of normal tissues, stem cells, as well as cancer cells. Existing data suggest that ABCG2 plays an important role in the maintenance of the stem cell phenotype and multidrug resistance of cancer cells. However, the potential role of ABCG2 in other cellular processes remains speculative and poorly understood.

Differentiation of human umbilical cord mesenchymal stromal cells into low immunogenic hepatocyte-like cells.

Background Aims: Mesenchymal stromal cells (MSC) isolated from several human tissues have been known to differentiate into the hepatic lineage in vitro, but the immunogenicity of the differentiated hepatocyte-like cells (DHC) has not been reported. Umbilical cord (UC) MSC are thought to be an attractive cell source for cell therapy because of their young age and low infection rate compared with adult tissue MSC.

Methods: Hepatic differentiation of UC-MSC was induced with a 2-step protocol.