The immunomodulatory effects of mesenchymal stem cells on long term pulmonary complications in an animal model exposed to a sulfur mustard analog

Neuro-inflammation plays a key role in the pathophysiology of brain infarction. Cell therapy offers a novel therapeutic option due to its effect on immunomodulatory effects. Amniotic stem cells, in particular, show promise owing to their low immunogenicity, tumorigenicity, and easy availability from amniotic membranes discarded following birth. We have successfully isolated and expanded human amniotic mesenchymal stem cells (hAMSCs). Herein, we evaluated the therapeutic effect of hAMSCs on neurological deficits after brain infarction as well as their immunomodulatory effects in a mouse model in order to understand their mechanisms of action. One day after permanent occlusion of the middle cerebral artery (MCAO), hAMSCs were intravenously administered. RT-qPCR for TNFα, iNOS, MMP2, and MMP9, immunofluorescence staining for iNOS and CD11b/c, and a TUNEL assay were performed 8 days following MCAO. An Evans Blue assay and behavioral tests were performed 2 days and several months following MCAO, respectively. The results suggest that the neurological deficits caused by cerebral infarction are improved in dose-dependent manner by the administration of hAMSCs. The mechanism appears to be through a reduction in disruption of the blood brain barrier and apoptosis in the peri-infarct region through the suppression of pro-inflammatory cytokines and the M2-to-M1 phenotype shift.

Download Full-text

Injectable collagen scaffold promotes swine myocardial infarction recovery by long-term local retention of transplanted human umbilical cord mesenchymal stem cells

Science China Life Sciences ◽

10.1007/s11427-019-1575-x ◽

2020 ◽

Author(s):

Qiang Wang ◽

Xiaojun He ◽

Bin Wang ◽

Jun Pan ◽

Chunying Shi ◽

...

Keyword(s):

Myocardial Infarction ◽

Stem Cells ◽

Mesenchymal Stem Cells ◽

Umbilical Cord ◽

Collagen Scaffold ◽

Human Umbilical Cord ◽

Injectable Collagen

Download Full-text

Chronic senescent human mesenchymal stem cells as possible contributor to the wound healing disorder after exposure to the alkylating agent sulfur mustard

Archives of Toxicology ◽

10.1007/s00204-020-02946-5 ◽

2021 ◽

Vol 95 (2) ◽

pp. 727-747

Author(s):

Simone Rothmiller ◽

Niklas Jäger ◽

Nicole Meier ◽

Thimo Meyer ◽

Adrian Neu ◽

...

Keyword(s):

Stem Cells ◽

Wound Healing ◽

Mesenchymal Stem Cells ◽

Alkylating Agent ◽

Chronic Wounds ◽

Sulfur Mustard ◽

Morphological Changes ◽

Human Mesenchymal Stem Cells ◽

Age Related

AbstractWound healing is a complex process, and disturbance of even a single mechanism can result in chronic ulcers developing after exposure to the alkylating agent sulfur mustard (SM). A possible contributor may be SM-induced chronic senescent mesenchymal stem cells (MSCs), unable to fulfil their regenerative role, by persisting over long time periods and creating a proinflammatory microenvironment. Here we show that senescence induction in human bone marrow derived MSCs was time- and concentration-dependent, and chronic senescence could be verified 3 weeks after exposure to between 10 and 40 µM SM. Morphological changes, reduced clonogenic and migration potential, longer scratch closure times, differences in senescence, motility and DNA damage response associated genes as well as increased levels of proinflammatory cytokines were revealed. Selective removal of these cells by senolytic drugs, in which ABT-263 showed initial potential in vitro, opens the possibility for an innovative treatment strategy for chronic wounds, but also tumors and age-related diseases.

Download Full-text

Senescence-Associated Secretory Phenotype Suppression Mediated by Small-Sized Mesenchymal Stem Cells Delays Cellular Senescence through TLR2 and TLR5 Signaling

Cells ◽

10.3390/cells10010063 ◽

2021 ◽

Vol 10 (1) ◽

pp. 63

Author(s):

Ji Hye Kwon ◽

Miyeon Kim ◽

Soyoun Um ◽

Hyang Ju Lee ◽

Yun Kyung Bae ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Cellular Senescence ◽

Small Cells ◽

Critical Determinant ◽

Senescent Phenotype ◽

Toll Like Receptor 2 ◽

Secretory Phenotype ◽

Major Factors

In order to provide a sufficient number of cells for clinical use, mesenchymal stem cells (MSCs) must be cultured for long-term expansion, which inevitably triggers cellular senescence. Although the small size of MSCs is known as a critical determinant of their fate, the main regulators of stem cell senescence and the underlying signaling have not been addressed. Umbilical cord blood-derived MSCs (UCB-MSCs) were obtained using size-isolation methods and then cultured with control or small cells to investigate the major factors that modulate MSC senescence. Cytokine array data suggested that the secretion of interukin-8 (IL-8) or growth-regulated oncogene-alpha (GROa) by senescent cells was markedly inhibited during incubation of small cells along with suppression of cognate receptor (C-X-C motif chemokine receptor2, CXCR2) via blockade of the autocrine/paracrine positive loop. Moreover, signaling via toll-like receptor 2 (TLR2) and TLR5, both pattern recognition receptors, drove cellular senescence of MSCs, but was inhibited in small cells. The activation of TLRs (2 and 5) through ligand treatment induced a senescent phenotype in small cells. Collectively, our data suggest that small cell from UCB-MSCs exhibit delayed cellular senescence by inhibiting the process of TLR signaling-mediated senescence-associated secretory phenotype (SASP) activation.

Download Full-text