In vitro comparison of immunological properties of cultured human mesenchymal cells from various sources

Activation of TLR4 of Mesenchymal Stem Cells Enhances the Regenerative Properties of Their Secretomes

Mesenchymal stem cells (MSC), like macrophages, can be polarized in vitro. In particular, activation of type 4 Toll-like receptor in MSC leads to the appearance of the so-called "proinflammatory" MSC phenotype (MSC1). We showed that secretome (conditioned media) of MSC1 can affect the wound healing processes: promote healing and modulate exudative inflammation and subsequent fibroplastic processes in the damaged area. These effects of secretomes of polarized MSC were superior to those of intact MSC.

Locally Delivered Umbilical Cord Mesenchymal Stromal Cells Reduce Chronic Inflammation in Long-Term Nonhealing Wounds: A Randomized Study

Inflammation is part of a complex biological response to injury that mediates a rapid mobilization of cells and triggers the restoration of tissue homeostasis. The systemic diseases of the connective tissues, repetitive strain injuries, neuropathy, and vascular impairment lead to the development of a chronic inflammatory state. In such cases, a forced intervention is required to trigger tissue regeneration. Mesenchymal stromal cells (MSCs) have been considered a perspective tool for regenerative medicine because of their ability to change the expression and secretory profile under the influence of signals from the microenvironment to perform a regulatory function at the site of tissue damage. In this study, MSCs were isolated from the human umbilical cord (UCMSCs). The ability of UCMSCs to regulate chronic inflammation was investigated in a randomized placebo-controlled pilot study to assess the efficacy and safety of UCMSC therapy in patients with nonhealing wounds. A total of 108 patients with chronic wounds of different etiologies were randomly divided into two groups according to the criteria of inclusion and exclusion. The group (n = 59) that was treated with a single local subcutaneous infusion of UCMSCs around the wound periphery showed a pronounced growth of granulation tissue, improved blood microcirculation, and reduction in wound size compared to the placebo group (n = 49). No prominent adverse events were detected in patients from the UCMSC group during the 1-year follow-up period. This research has demonstrated that locally delivered allogeneic UCMSCs can contribute to chronic wound repair and provide an additional support toward new therapeutic strategies. Registration certificate №FS2006/341 was issued by the Federal Service for Surveillance in Healthcare.

Human umbilical cord mesenchymal stem cells improve irradiation-induced skin ulcers healing of rat models

Irradiation-induced skin ulcers can be resultant from nuclear accident or reaction to radiation therapy of tumor and is intractable for healing. Human umbilical cord mesenchymal stem cells (hUC-MSCs) have been considered to be the potential therapeutic tools for tissue regeneration. However, the underlying mechanisms are still not well understood. This study aims to investigate the effects of hUC-MSCs on irradiation-induced skin ulcers healing and the related mechanisms. The ulcers were induced by irradiating the skin of adult SD rats. The ulcers of SD rats were treated with vehicle or hUC-MSCs donated from mother giving birth. The ulcer healing was measured by imaging the healing rate and the H&E staining. CD31 and VEGF expression was measured with immunohistochemistry assay. iTRAQ proteomics analysis was used to analyze the signaling pathway. The results showed that hUC-MSCs improved healing of irradiation-induced skin ulcers in vivo using a rat model of skin ulcer. Transplantation of hUC-MSCs promoted keratin generation and keratinocytes proliferation of ulcer areas. Furthermore, the results demonstrated that hUC-MSCs increased expression of CD31 and VEGF in ulcers and promoted neovascularization. iTRAQ proteomics analysis results indicated that PI3K/Akt signaling pathway involved in hUC-MSCs-mediated repairing of irradiation-induced skin ulcer. In conclusion, human umbilical cord mesenchymal stem cells promoted neovascularization and re-epithelization, and improved healing of irradiation-induced skin ulcers. This healing improvement may be conducted through activating the PI3K/Akt signaling pathway, however, which needs to be proven by the further investigations.

Intracerebral and Intravenous Transplantation Represents a Favorable Approach for Application of Human Umbilical Cord Mesenchymal Stromal Cells in Intracerebral Hemorrhage Rats

Background

Intracerebral hemorrhage (ICH) is one severe subtype of stroke, with a very complex pathology. Stem cell-based therapy holds promising potential in the treatment of neurological disorders. Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) have a therapeutic effect in recovery from brain damage following ICH. The aim of this study was to identify an effective and convenient way of using UC-MSCs in the ICH rat model.

Material/Methods

CM-DiI-labeled human UC-MSCs were transplanted intracerebrally or intravenously into collagenase VII-induced ICH rat models. Neurological function was evaluated before ICH and at 0, 7, 14, 21, and 28 days after treatment. ICH rats were sacrificed to evaluate the injury volume. Neurogenesis and angiogenesis and vascular areas were investigated using microtubule-associated protein 2 (MAP2), glial fibrillary acidic protein (GFAP), and 4′,6-diamidino-2-phenylindole (DAPI) immunohistochemistry at two weeks after transplantation.

Results

The intracerebral and intravenous administration of UC-MSCs both resulted in significant improvement in neurological function and decrease in injury volume of ICH rats. Transplanted UC-MSCs were chemotactic in vivo and showed a predominant distribution around the ICH region. In addition, UC-MSCs could integrate into the cerebral vasculature in both groups.

Conclusions

Both intracerebral and intravenous administration of UC-MSCs could have a favorable effect on recovery of neurological function in ICH rats, although the fundamental mechanisms may be different between the two groups. Our data suggest that intravenous implantation of UC-MSCs could serve as a favorable approach for cell-based therapy in central nervous system (CNS) diseases according to clinical needs.

Modulation of Immune Responses by Mesenchymal Stromal Cells

This concise review provides an assessment of one of the most conceptually and practically important properties of mesenchymal stromal cells, their ability to modulate immune responses, including underlying cellular and molecular mechanisms and prospects of clinical application in the treatment of autoimmune and other immunological disorders.

Human umbilical cord mesenchymal stem cells transplantation promotes cutaneous wound healing of severe burned rats

BACKGROUND

Severe burns are a common and highly lethal trauma. The key step for severe burn therapy is to promote the wound healing as early as possible, and reports indicate that mesenchymal stem cell (MSC) therapy contributes to facilitate wound healing. In this study, we investigated effect of human umbilical cord MSCs (hUC-MSCs) could on wound healing in a rat model of severe burn and its potential mechanism.

METHODS

Adult male Wistar rats were randomly divided into sham, burn, and burn transplanted hUC-MSCs. GFP labeled hUC-MSCs or PBS was intravenous injected into respective groups. The rate of wound closure was evaluated by Image Pro Plus. GFP-labeled hUC-MSCs were tracked by in vivo bioluminescence imaging (BLI), and human-specific DNA expression in wounds was detected by PCR. Inflammatory cells, neutrophils, macrophages, capillaries and collagen types I/III in wounds were evaluated by histochemical staining. Wound blood flow was evaluated by laser Doppler blood flow meter. The levels of proinflammatory and anti-inflammatory factors, VEGF, collagen types I/III in wounds were analyzed using an ELISA.

RESULTS

We found that wound healing was significantly accelerated in the hUC-MSC therapy group. The hUC-MSCs migrated into wound and remarkably decreased the quantity of infiltrated inflammatory cells and levels of IL-1, IL-6, TNF-α and increased levels of IL-10 and TSG-6 in wounds. Additionally, the neovascularization and levels of VEGF in wounds in the hUC-MSC therapy group were markedly higher than those in other control groups. The ratio of collagen types I and III in the hUC-MSC therapy group were markedly higher than that in the burn group at indicated time after transplantation.

CONCLUSION

The study suggests that hUC-MSCs transplantation can effectively improve wound healing in severe burned rat model. Moreover, these data might provide the theoretical foundation for the further clinical application of hUC-MSC in burn areas.

Human umbilical cord mesenchymal stem cells reduce systemic inflammation and attenuate LPS-induced acute lung injury in rats

Background

Mesenchymal stem cells (MSCs) possess potent immunomodulatory properties and simultaneously lack the ability to illicit immune responses. Hence, MSCs have emerged as a promising candidate for cellular therapeutics for inflammatory diseases. Within the context of this study, we investigated whether human umbilical cord-derived mesenchymal stem cells (UC-MSCs) could ameliorate lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in a rat model.

Methods

ALI was induced via injection of LPS. Rats were divided into three groups: (1) saline group(control), (2) LPS group, and (3) MSC + LPS group. The rats were sacrificed at 6, 24, and 48 hours after injection. Serum, bronchoalveolar lavage fluid (BALF), and lungs were collected for cytokine concentration measurements, assessment of lung injury, and histology.

Results

UC-MSCs increased survival rate and suppressed LPS-induced increase of serum concentrations of pro-inflammatory mediators TNF-α, IL-1β, and IL-6 without decreasing the level of anti-inflammatory cytokine IL-10. The MSC + LPS group exhibited significant improvements in lung inflammation, injury, edema, lung wet/dry ratio, protein concentration, and neutrophil counts in the BALF, as well as improved myeloperoxidase (MPO) activity in the lung tissue. Furthermore, UC-MSCs decreased malondialdehyde (MDA) production and increased Heme Oxygenase-1 (HO-1) protein production and activity in the lung tissue.

Conclusion

UC-MSCs noticeably increased the survival rate of rats suffering from LPS-induced lung injury and significantly reduced systemic and pulmonary inflammation. Promoting anti-inflammatory homeostasis and reducing oxidative stress might be the therapeutic basis of UC-MSCs.

Intradermal injections of equine allogeneic umbilical cord-derived mesenchymal stem cells are well tolerated and do not elicit immediate or delayed hypersensitivity reactions

BACKGROUND AIMS. The use of allogeneic mesenchymal stem cells (MSC) to treat acute equine lesions would greatly expand equine cellular therapy options; however, the safety and antigenicity of these cells have not been well-studied. We hypothesized that equine allogeneic umbilical cord tissue (UCT)-derived MSC would not elicit acute graft rejection or a delayed-type hypersensitivity response when injected intradermally. METHODS. Six Quarterhorse yearlings received 12 intradermal injections (autologous MSC, allogeneic MSC, positive control and negative control, in triplicate) followed by the same series of 12 injections, 3-4 weeks later, at another site. Wheals were measured and palpated at 0.25, 4, 24, 48, 72 h and 7 days post-injection. Biopsies were obtained at 48 and 72 h and 7 days post-injection. Mixed leukocyte reactions were performed 1 week prior to the first injections and 3 weeks after the second injections. RESULTS. There were no adverse local or systemic responses to two intradermal injections of allogeneic MSC. MSC injection resulted in minor wheal formation, characterized by mild dermatitis, dermal edema and endothelial hyperplasia, that fully resolved by 48-72 h. No differences were noted between allogeneic and autologous MSC. The second injection of MSC did not elicit more significant physical or histomorphologic alterations compared with the first MSC injection. Neither allogeneic nor autologous UCT-derived MSC stimulated or suppressed baseline T-cell proliferation in vitro prior to or after two MSC administrations. CONCLUSIONS. Equine allogeneic UCT MSC may be safely administered intradermally on multiple occasions without eliciting a measurable cellular immune response.

Mesenchymal cells of the decidual tooth pulp: cytophenotype and initial evaluation of possibility of their use in bone tissue engineering

Cultures of mesenchymal cells from human decidual tooth pulp were derived. The phenotype and capacity to osteogenic and adipogenic differentiation of these cells are close to those of bone marrow mesenchymal stem cells. Decidual tooth pulp mesenchymal cells populate biodegraded polylactide scaffolds and hence, can be used for the creation of tissue engineering transplants for bone defect repair. Storage of decidual tooth pulp mesenchymal cells in the stem cell cryobanks together with umbilical blood will appreciably extent the periods of age for collection of juvenile autologous stem cells for use throughout the life span.