Comparison of Antibacterial and Immunological Properties of Mesenchymal Stem/Stromal Cells from Equine Bone Marrow, Endometrium, and Adipose Tissue

Abstract

Equine mesenchymal stem/stromal cells (MSCs) are multipotent cells that are widely used for treatment of musculoskeletal injuries, and there is significant interest in expanding their application to nonorthopedic conditions. MSCs possess antibacterial and immunomodulatory properties that may be relevant for combating infection; however, comparative studies using MSCs from different origins have not been carried out in the horse, and this was the focus of this study. Our results showed that MSC-conditioned media attenuated the growth of Escherichia coli, and that this effect was, on average, more pronounced for endometrium (EM)-derived and adipose tissue (AT)-derived MSCs than for bone marrow (BM)-derived MSCs. In addition, the antimicrobial lipocalin-2 was expressed at mean higher levels in EM-MSCs than in AT-MSCs and BM-MSCs, and the bacterial component lipopolysaccharide (LPS) stimulated its production by all three MSC types. We also showed that MSCs express interleukin-6 (IL-6), IL-8, monocyte chemoattractant protein-1, chemokine ligand-5, and Toll-like receptor 4, and that, in general, these cytokines were induced in all cell types by LPS. Low expression levels of the macrophage marker colony-stimulating factor 1 receptor were detected in BM-MSCs and EM-MSCs but not in AT-MSCs. Altogether, these findings suggest that equine MSCs from EM, AT, and BM have both direct and indirect antimicrobial properties that may vary between MSCs from different origins and could be exploited toward improvement of regenerative therapies for horses.

Developments in marine invertebrate primary culture reveal novel cell morphologies in the model bivalve Crassostrea gigas

“…Flow cytometry has been used to characterise C. gigas hemocytes, demonstrating this approach can be applied to molluscan cells (Jiang et al, 2016). In experimentally challenging mammalian cells clusters of differentiation and qPCR can be used to characterise a population of cells (Cortes et al, 2018). These approaches have not been developed in molluscan culture, making it difficult to determine what cell types have been cultured beyond morphological characterisation.…”

Canine Bone Marrow Mesenchymal Stem Cell Conditioned Media Affect Bacterial Growth, Biofilm-Associated Staphylococcus aureus and AHL-Dependent Quorum Sensing

“…Little is currently known about the precise mechanism underlying the antibacterial effects of MSCs. Recent data suggest that MSCs exert strong antimicrobial effects through indirect and direct mechanisms: indirectly, through their role in the host immune response against pathogens, especially in the dynamic coordination of the immune system [ 33 , 34 , 35 , 36 ] or by increasing the activity of phagocytes [ 6 , 32 , 37 , 38 ]; and directly, through the secretion of antimicrobial peptides and proteins (AMPs) [ 1 , 5 , 6 , 7 , 8 ]. Moreover, MSCs have been found to release circular membrane fragments called microvesicles (MVs), containing numerous proteins, mRNAs, microRNAs, organelles and lipids involved in cell-cell communication and the transfer of cellular material.…”

Antimicrobial Effects of Conditioned Medium From Amniotic Progenitor Cells in vitro and in vivo: Toward Tissue Regenerative Therapies for Bovine Mastitis

“…The authors speculate that this effect can be explained by the call of neutrophils within the vascular compartment mediated by IL-10 (68). Equine MSCs from different tissue are able to express some immunomodulatory genes such as monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), interleukin-8 (IL-8), and chemokine ligand-5 (CCL5), suggesting that respective cytokines may help limit infection indirectly by recruiting and activating immune cells (19).…”

“…have antimicrobial properties (17)(18)(19). Studies using models of infection-induced organ damage have shown that MSCs can exhibit antibacterial properties by the release of soluble molecules, such as the peptides catelicidine LL-37 (20) and lipocalin-2 (21), which lead to the clearance of bacteria.…”