Immunomodulatory effects of mesenchymal stem cell-conditioned media on lipopolysaccharide of Vibrio cholerae as a vaccine candidate

The effect of mesenchymal stem cell conditioned medium incorporated within chitosan nanostructure in clearance of common gastroenteritis bacteria in-vitro and in-vivo

Gastroenteritis infection is a major public health concern worldwide, especially in developing countries due to the high annual mortality rate. The antimicrobial and antibiofilm activity of human mesenchymal stem cell-derived conditioned medium (hMSCsCM) encapsulated in chitosan nanoparticles (ChNPs) was studied in vitro and in vivo against common gastroenteritis bacteria. The synthesized ChNPs were characterized using Zeta potential, scanning electron microscopy (SEM), and dynamic light scattering (DLS) techniques. HMSC-derived conditioned medium incorporated into chitosan NPs (hMSCsCM-ChNPs) composite was fabricated by chitosan nanoparticles loaded with BM-MSCs (positive for CD73 and CD44 markers). The antimicrobial and antibiofilm activity of composite was investigated against four common gastroenteritis bacteria (Campylobacter jejuni ATCC29428, Salmonella enteritidis ATCC13076, Shigella dysenteriae PTCC1188, and E. coli ATCC25922) in-vitro and in-vivo. Majority of ChNPs (96%) had an average particle size of 329 nm with zeta potential 7.08 mV. The SEM images confirmed the synthesis of spherical shape for ChNPs and a near-spherical shape for hMSCsCM-ChNPs. Entrapment efficiency of hMSCsCM-ChNPs was 75%. Kinetic profiling revealed that the release rate of mesenchymal stem cells was reduced following the pH reduction. The antibacterial activity of hMSCsCM-ChNPs was significantly greater than that of hMSCsCM and ChNPs at dilutions of 1:2 to 1:8 (P < 0.05) against four common gastroenteritis bacteria. The number of bacteria present decreased more significantly in the group of mice treated with the hMSCsCM-ChNPs composite than in the groups treated with hMSCsCM and ChNPs. The antibacterial activity of hMSCsCM against common gastroenteritis bacteria in an in vivo assay decreased from > 106 CFU/ml to approximately (102 to 10) after 72 h. Both in vitro and in vivo assays demonstrated the antimicrobial and antibiofilm activities of ChNPs at a concentration of 0.1% and hMSCsCM at a concentration of 1000 μg/ml to be inferior to that of hMSCsCM-ChNPs (1000 μg/ml + 0.1%) composite. These results indicated the existence of a synergistic effect between ChNPs and hMSCsCM. The designed composite exhibited notable antibiofilm and antibacterial activities, demonstrating optimal release in simulated intestinal lumen conditions. The utilization of this composite is proposed as a novel treatment approach to combat gastroenteritis bacteria in the context of more challenging infections.

Secretome of adipose derived-mesenchymal stem cells reduces the Vibrio cholerae attachment to Caco-2 cells and subsequent inflammatory responses

Background and Objectives

Mesenchymal Stem Cells (MSCs) can repair gastrointestinal tract damage. The Secretome of MSCs has a high capacity to inhibit bacterial colonization and the subsequent inflammatory responses of Vibrio cholerae.

Materials and Methods

The Caco-2 cells were treated with adipose-derived MSCs (AD-MSCs) secretome and then infected with V. cholerae. Subsequently, the bacterial attachment and invasion, cholera toxin gene expression, PGE2 and IL-6 secretion, TNF-α, IL-1β, and IL-8 expression, and apoptosis of Caco-2 cells were evaluated.

Results

The secretome of AD-MSCs significantly reduced the V. cholerae attachment and internalization on Caco-2 epithelial cells (P<0.0001). The cholera toxin (Ctx-B) gene expression (FR=4.56 ± 0.66) and PGE2 production (P=0.0007) were also significantly reduced. The production of NO and TNF-α, IL-1β, and IL-8 pro-inflammatory cytokines were significantly (P<0.05) reduced in exposure to the secretome of AD-MSCs. Secretome also improved a significant 81.33% increase in IL-6 production (128.1 ± 37.6 pg/mL) and showed a 12.36% significant decrease in epithelial cell apoptosis (P< 0.0001) after exposure to V. cholerae.

Conclusion

The secretome of AD-MSCs can play a critical role in inhibiting bacterial colonization, and subsequent inflammatory responses, and maintaining the integrity of the epithelial barrier. The secretome may be effective in the prevention of hypovolemic shock.

Pretreated Mesenchymal Stem Cells and Their Secretome: Enhanced Immunotherapeutic Strategies

Mesenchymal stem cells (MSCs) with self-renewing, multilineage differentiation and immunomodulatory properties, have been extensively studied in the field of regenerative medicine and proved to have significant therapeutic potential in many different pathological conditions. The role of MSCs mainly depends on their paracrine components, namely secretome. However, the components of MSC-derived secretome are not constant and are affected by the stimulation MSCs are exposed to. Therefore, the content and composition of secretome can be regulated by the pretreatment of MSCs. We summarize the effects of different pretreatments on MSCs and their secretome, focusing on their immunomodulatory properties, in order to provide new insights for the therapeutic application of MSCs and their secretome in inflammatory immune diseases.

Mesenchymal stromal cells (MSCs) and their exosome in acute liver failure (ALF): a comprehensive review

Recently, mesenchymal stromal cells (MSCs) and their derivative exosome have become a promising approach in the context of liver diseases therapy, in particular, acute liver failure (ALF). In addition to their differentiation into hepatocytes in vivo, which is partially involved in liver regeneration, MSCs support liver regeneration as a result of their appreciated competencies, such as antiapoptotic, immunomodulatory, antifibrotic, and also antioxidant attributes. Further, MSCs-secreted molecules inspire hepatocyte proliferation in vivo, facilitating damaged tissue recovery in ALF. Given these properties, various MSCs-based approaches have evolved and resulted in encouraging outcomes in ALF animal models and also displayed safety and also modest efficacy in human studies, providing a new avenue for ALF therapy. Irrespective of MSCs-derived exosome, MSCs-based strategies in ALF include administration of native MSCs, genetically modified MSCs, pretreated MSCs, MSCs delivery using biomaterials, and also MSCs in combination with and other therapeutic molecules or modalities. Herein, we will deliver an overview regarding the therapeutic effects of the MSCs and their exosomes in ALF. As well, we will discuss recent progress in preclinical and clinical studies and current challenges in MSCs-based therapies in ALF, with a special focus on in vivo reports.