The Effect of Collagen and Fibrin Hydrogels Encapsulated with Adipose Tissue Mesenchymal Stem Cell-Derived Exosomes for Treatment of Spinal Cord Injury in a Rat Model.

Background: Mesenchymal stem cell (MSC) derived exosomes (MSC-DE) have been demonstrated to be potential candidates for the treatment of rat spinal cord injury (SCI). Objective: The effect of AD-MSC and AD-MSC-DE encapsulated into collagen and fibrin hydrogels on the treatment of SCI in a rat animal model was investigated for introducing a new effective SCI treatment method. Materials and Methods: The AD-MSC-DE was isolated using ultra-centrifugation at 100,000×g for 120 min and characterized by different methods. Fibrin and collagen hydrogels were synthesized and then mixed with AD-MSC-DE suspension. the characterized AD-MSC-DE were encapsulated into collagen and fibrin hydrogels. eighteen adult male Wister rats were randomly classified into 3 equal groups (n=6): the control group (SCI rat without treatment), SCI rat treated with either AD-MSC-DE encapsulated in collagen hydrogel or encapsulated in fibrin hydrogel groups. the treatment approaches were evaluated using clinical, histological, and molecular assays. Results: The AD-MSC-DE encapsulated into fibrin and collagen groups showed better clinical function than the control group. The AD-MSC-DE encapsulated into fibrin and collagen also improved SCI-induced polio and leuko-myelomalacia and leads to higher expression of NF protein than the control group. In the AD-MSC-DE encapsulated into collagen and fibrin leads to up-regulation the mean levels of NEFL (23.82 and 24.33, respectively), eNOS (24.31 and 24.53, respectively), and CK19 mRNAs (24.23 and 23.98, respectively) compared to the control group. Conclusion: The AD-MSC-DE encapsulated within ECM-based hydrogel scaffolds such as collagen and fibrin can regenerate the injured nerve in SCI rats and reduce spinal cord lesion-induced central neuropathic pain.

Therapeutic potential of targeting regulatory mechanisms of hepatic stellate cell activation in liver fibrosis.

Hepatic fibrosis is a manifestation of different etiologies of liver disease with the involvement of multiple mediators in complex network interactions. Activated hepatic stellate cells (aHSCs) are the central driver of hepatic fibrosis, given their potential to induce connective tissue formation and extracellular matrix (ECM) protein accumulation. Therefore, identifying the cellular and molecular pathways involved in the activation of HSCs is crucial in gaining mechanistic and therapeutic perspectives to more effectively target the disease. In addition to a comprehensive summary of our current understanding of the role of HSCs in liver fibrosis, we also discuss here the proposed therapeutic strategies based on targeting HSCs.

The Effect of Laser Photobiomodulation on Periodontal Ligament Stem Cells.

Photobiomodulation (PBM) is considered as a noninvasive procedure with the potential of inducing favorable changes in cellular behavior. In this study, we aimed to evaluate the effects of near-infrared low-intensity laser PBM on proliferation, viability and osteogenic differentiation of stem cells isolated from human periodontal ligament. A 940-nm diode laser with an energy density of 4 J cm-2 in a 100-mW continuous wave was used for irradiation in 3 sessions every 48h. Cell viability was measured 24, 48 and 72 h after irradiation. The effects of laser on mineralized tissue deposition were evaluated by using Alizarin red staining after dividing cells into three groups of nonosteogenic medium (C-), an osteogenic medium without laser (C+), and an osteogenic medium with laser irradiation (L+). Gene expression levels were also evaluated by real-time PCR. Our results showed no significant difference between MTT levels of the study and control groups. After 14 and 21 days, both L+ and C+ groups showed an increase in mineralized tissue formation compared to the C- group. There was an increase in VEGF and BMP expressions compared to C-. In conclusion, the irradiation setting used in this study may be able to improve mineralized tissue deposition.

The attentive focus on T cell-mediated autoimmune pathogenesis of psoriasis, lichen planus and vitiligo.

T cell-mediated autoimmune skin diseases develop as a result of the aberrant immune response to the skin cells with T cells playing a central role. These chronic inflammatory skin diseases encompass various types including psoriasis, lichen planus and vitiligo. These diseases show similarities in their immune-pathophysiology. In the last decade, immunomodulating agents have been very successful in the management of these diseases thanks to a better understanding of the pathophysiology. In this review, we will discuss the immunopathogenic mechanisms and highlight the role of T lymphocytes in psoriasis, lichen planus and vitiligo. This study could provide new insights into a better understanding of targeted therapeutic pathways and biological therapies.

Dendritic Cell-Based Therapy Using LY6E Peptide with a Putative Role Against Colorectal Cancer.

INTRODUCTION: Albeit early stage gastrointestinal (GI) carcinomas have a good prognosis if treated with surgery, diagnosis is often confirmed at a late stage and efficacious drugs are lacking. Recent progress in immune-based therapies has focused on dendritic cells (DCs), aiming to elicit tumor-specific responses by inducing immunological memory. Our previous microarray study indicated that a biomarker, termed lymphocyte antigen-6E (LY6E), is commonly overexpressed in two potentially lethal GI cancers: those of colon and stomach. In this study, we examined the antigenic potency of LY6E in stimulating DCs. METHODS: Following isolation, differentiation, and maturation of mononuclear cells, DCs were pulsed with LY6E peptide, a protein related to major histocompatibility complex (MHC) class I/II. Subsequently, DCs were co-cultured with mouse splenocytes to assess antigen-specific T-cell proliferation. Elucidated cytotoxic T-lymphocyte responses were assessed using subcutaneous colorectal murine tumor models. RESULTS: Our in vitro results suggest that DCs loaded with LY6E peptide antigen are capable of stimulating and inducing proliferation of murine T-cells. Furthermore, our in vivo results demonstrate that LY6E peptide has a substantial impact on provoking immune responses against induced colon cancer in mice. DISCUSSION: In conclusion, based on the overexpression of LY6E in colorectal, gastric, and pancreatic cancers, the role of this peptide should be further investigated with a goal of developing new therapies for these challenging diseases.