Endometritis and In Vitro PGE2 Challenge Modify Properties of Cattle Endometrial Mesenchymal Stem Cells and Their Transcriptomic Profile

Characterization of circulating microRNA profiles of postpartum dairy cows with persistent subclinical endometritis

Subclinical endometritis (SCE) is an unresolved inflammation of the endometrium of postpartum dairy cows, seriously affecting fertility. Current diagnosis, which relies on uterine cytology or even more invasive biopsy sampling, would benefit from the identification of blood-based diagnostic biomarkers. Due to the known role of microRNAs (miRNAs) in other diseases, this case-control study evaluated the cell-free circulating miRNA profiles of SCE cows, and the network of transcripts predicted to interact with those miRNAs, previously identified as differentially expressed genes (DEG) in the endometrium of the same cows. Healthy (H, n = 6) and persistent SCE (n = 11) cows characterized by endometrial cytology and biopsy were blood sampled at 21 and 44 d postpartum (DPP). Following extraction of cell-free plasma miRNAs and RNA-seq analysis, differential abundance analysis of miRNAs was performed with the DESeq2 R package (adjusted p-value of 0.05), and in silico prediction of miRNA-interacting genes on a sequence complementary basis was conducted using the miRWalk database. The principal component analysis showed a clear clustering between groups of uterine health phenotypes (H vs. SCE), although the clustering between groups was less pronounced at 44 DPP than at 21 DPP. No effect of the stage (21 vs. 44 DPP) was observed. A total of 799 known circulating miRNAs were identified, from which 34 demonstrated differential abundance between H and SCE cows (12 less abundant and 22 more abundant in SCE than in H cows). These 34 miRNAs are predicted to interact with 10,104 transcripts, among which 43, 81, and 147 were previously identified as differentially expressed in, respectively, endometrial luminal epithelial, glandular epithelial, and stromal cells of the same cows. This accounts for approximately half of the DEG identified between those H and SCE cows, including genes involved in endometrial cell proliferation, angiogenesis and immune response, whose dysregulation in SCE cows may impair pregnancy establishment. From 219 miRNAs with mean normalized read counts above 100, the presence and abundance of miR-425-3p and miR-2285z had the highest discriminatory level to differentiate SCE from H cows. In conclusion, despite apparent confinement to the endometrium, SCE is associated with a distinct circulating miRNA profile, which may represent a link between the systemic changes associated with disease and the endometrial immune response. The validation of a miRNA panel consisting of circulating cell-free miR-425-3p and miR-2285z may prove a relevant advancement for the noninvasive diagnosis of persistent SCE.

Validation of multiparametric panels for bovine mesenchymal stromal cell phenotyping

Bovine mesenchymal stromal cells (MSCs) display important features that render them valuable for cell therapy and tissue engineering strategies, such as self-renewal, multi-lineage differentiation, as well as immunomodulatory properties. These cells are also promising candidates to produce cultured meat. For all these applications, it is imperative to unequivocally identify this cell population. The isolation and in vitro tri-lineage differentiation of bovine MSCs is already described, but data on their immunophenotypic characterization is not yet complete. The currently limited availability of monoclonal antibodies (mAbs) specific for bovine MSC markers strongly hampers this research. Following the minimal criteria defined for human MSCs, bovine MSCs should express CD73, CD90, and CD105 and lack expression of CD14 or CD11b, CD34, CD45, CD79α, or CD19, and MHC-II. Additional surface proteins which have been reported to be expressed include CD29, CD44, and CD106. In this study, we aimed to immunophenotype bovine adipose tissue (AT)-derived MSCs using multi-color flow cytometry. To this end, 13 commercial Abs were screened for recognizing bovine epitopes using the appropriate positive controls. Using flow cytometry and immunofluorescence microscopy, cross-reactivity was confirmed for CD34, CD73, CD79α, and CD90. Unfortunately, none of the evaluated CD105 and CD106 Abs cross-reacted with bovine cells. Subsequently, AT-derived bovine MSCs were characterized using multi-color flow cytometry based on their expression of nine markers. Bovine MSCs clearly expressed CD29 and CD44, and lacked expression of CD14, CD45, CD73, CD79α, and MHCII, while a variable expression was observed for CD34 and CD90. In addition, the mRNA transcription level of different markers was analyzed using reverse transcription quantitative polymerase chain reaction. Using these panels, bovine MSCs can be properly immunophenotyped which allows a better characterization of this heterogenous cell population.

Comparison of proliferation and osteogenic differentiation potential of bovine adipose tissue and bone marrow derived stem cells

Bone marrow derived stem cells (BMSC) are the most utilized cell type in the field of bone regeneration. Although BMSC are both safe and efficacious, the search for alternative sources for stem cells continues. We investigated bovine BMSC and adipose tissue derived mesenchymal stem cells (ATSC) using immunofluorescence and PCR. We further compared the osteogenic differentiation potentials of both sources of stem cells. We assessed alkaline phosphatase (ALP) enzyme levels and calcium deposition in differentiating cells at days 7, 14 and 21 to compare the osteogenic differentiation capability of both cell types. We found that ATSC expressed significantly higher ALP levels compared to BMSC throughout osteogenic differentiation. Calcium deposition was greater in ATSC than BMSC at days 7 and 14. By the end of day 21, BMSC produced greater calcium deposition. We found that ATSC undergo osteogenic differentiation more rapidly than BMSC, but BMSC provide greater mineralization over longer periods.

An Update on Applications of Cattle Mesenchymal Stromal Cells

Simple Summary

Among livestock species, cattle are crucially important for the meat and milk production industry. Cows can be affected by different pathologies, such as mastitis, endometritis and lameness, which can negatively affect either food production or reproductive efficiency. The use of mesenchymal stromal cells (MSCs) is a valuable tool both in the treatment of various medical conditions and in the application of reproductive biotechnologies. This review provides an update on state-of-the-art applications of bovine MSCs to clinical treatments and reproductive biotechnologies.

Abstract

Attention on mesenchymal stromal cells (MSCs) research has increased in the last decade mainly due to the promising results about their plasticity, self-renewal, differentiation potential, immune modulatory and anti-inflammatory properties that have made stem cell therapy more clinically attractive. Furthermore, MSCs can be easily isolated and expanded to be used for autologous or allogenic therapy following the administration of either freshly isolated or previously cryopreserved cells. The scientific literature on the use of stromal cells in the treatment of several animal health conditions is currently available. Although MSCs are not as widely used for clinical treatments in cows as for companion and sport animals, they have the potential to be employed to improve productivity in the cattle industry. This review provides an update on state-of-the-art applications of bovine MSCs to clinical treatments and reproductive biotechnologies.

Adipose Tissue- and Bone Marrow-Derived Mesenchymal Stem Cells from Sheep: Culture Characteristics

Simple Summary

Mesenchymal stem cells (MSCs) are available in minuscule numbers in the body or placental tissues. These cells have mostly been harvested from bone marrow and adipose tissue. To broaden the currently available knowledge, the current study provides (a) information on the feasibility of isolation of MSCs at different ambient temperatures, (b) details of MSCs’ culture characteristics with respect to the physiological status of the donor, and (c) information on the viability of cryopreserved cells. Bone marrow harbors a higher mononuclear cell fraction than that of the adipose tissue, although percent adherent cells are comparably more in adipose tissue. MSCs from a pregnant donor show enhanced proliferation and differentiation potential, although further studies are desired. The cryopreserved cells have comparable characteristics to that of the fresh cells. In conclusion, donor animals’ tissue type and physiological status may affect MSCs’ characteristics and should be taken into consideration while applying in clinical settings.

Abstract

The current study demonstrates the culture characteristics of adipose tissue and bone marrow-derived mesenchymal stem cells (MSC). The study evaluates the effect of ambient temperature, physiological status of the donor and the tissue source on sheep (Ovis aries) mesenchymal stem cells. The tissue samples were harvested from full term pregnant female sheep (n = 9) and male sheep (n = 10). Adipose tissue was harvested from n = 9 sheep and bone marrow from n = 10 sheep. The samples (adipose tissue, n = 2; bone marrow, n = 3) transported at cold ambient temperature (<10 °C) failed to yield MSCs while those (n = 14) at higher (>20 °C) ambient temperature successfully yielded MSCs. Bone marrow mononuclear cell (MNC) fraction was higher than the adipose tissue-derived stromal vascular fraction (SVF), but the percent adherent cells (PAC) was higher in the later cell fraction. Adipose tissue-derived MSCs from the full term female sheep had a significantly (p < 0.05) higher proliferation potential as compared to those of the male sheep-derived MSCs. Female sheep MSCs also had rapid differentiation potential. The cryopreserved MSCs had morphological features comparable to that of the fresh cells. In conclusion, the tissue type and physiological status of donor animal may affect MSCs’ characteristics and should be taken into consideration while applying in clinical settings.

Mesenchymal Stem/Progenitor Cells: The Prospect of Human Clinical Translation

Mesenchymal stem/progenitor cells (MSCs) are key players in regenerative medicine, relying principally on their differentiation/regeneration potential, immunomodulatory properties, paracrine effects, and potent homing ability with minimal if any ethical concerns. Even though multiple preclinical and clinical studies have demonstrated remarkable properties for MSCs, the clinical applicability of MSC-based therapies is still questionable. Several challenges exist that critically hinder a successful clinical translation of MSC-based therapies, including but not limited to heterogeneity of their populations, variability in their quality and quantity, donor-related factors, discrepancies in protocols for isolation, in vitro expansion and premodification, and variability in methods of cell delivery, dosing, and cell homing. Alterations of MSC viability, proliferation, properties, and/or function are also affected by various drugs and chemicals. Moreover, significant safety concerns exist due to possible teratogenic/neoplastic potential and transmission of infectious diseases. Through the current review, we aim to highlight the major challenges facing MSCs' human clinical translation and shed light on the undergoing strategies to overcome them.

Recovery and maintenance of NESTIN expression in umbilical cord-MSC using a novel culture medium

Mesenchymal stem cells (MSC) are a popular candidate in cellular therapy for many diseases. MSCs are well known by their feature of self-renewal and their differentiation potential. NESTIN is a cytoskeletal protein expressed in MSC that functions directly in cell proliferation and differentiation. Here, we demonstrated that adding UltraGRO, a medium supplement, could maintain and partially recover the expression of NESTIN in human umbilical cord derived MSCs (UC-MSCs). Furthermore, the UC-MSCs cultured with UltraGRO showed a better immunomodulation ability in a colitis mouse model compared with those cultured in other types of media. This indicates that the use of novel culture medium benefits the maintenance of NESTIN expression and NESTIN may be one of the vital factors that regulates the performance of MSCs.

Mesenchymal stem cell: Basic research and potential applications in cattle and buffalo

Characteristic features like self-renewal, multilineage differentiation potential, and immune-modulatory/anti-inflammatory properties, besides the ability to mobilize and home distant tissues make stem cells (SCs) a lifeline for an individual. Stem cells (SCs) if could be harvested and expanded without any abnormal change may be utilized as an all-in-one solution to numerous clinical ailments. However, slender understanding of their basic physiological properties, including expression potential, behavioral alternations during culture, and the effect of niche/microenvironment has currently restricted the clinical application of SCs. Among various types of SCs, mesenchymal stem cells (MSCs) are extensively studied due to their easy availability, straightforward harvesting, and culturing procedures, besides, their less likelihood to produce teratogens. Large ruminant MSCs have been harvested from various adult tissues and fetal membranes and are well characterized under in vitro conditions but unlike human or other domestic animals in vivo studies on cattle/buffalo MSCs have mostly been aimed at improving the animals' production potential. In this document, we focused on the status and potential application of MSCs in cattle and buffalo.

Endometrial Stem Cells in Farm Animals: Potential Role in Uterine Physiology and Pathology

The endometrium is an accessible source of mesenchymal stem cells. Most investigations of endometrial mesenchymal stem cells (eMSCs) have been conducted in humans. In animals, particularly in livestock, eMSC research is scarce. Such cells have been described in the bovine, ovine, caprine, porcine, and equine endometrium. Here we provide the state of the art of eMSCs in farm animals with a focus on the bovine species. In bovines, eMSCs have been identified during the phases of the estrous cycle, during which their functionality and the presence of eMSC-specific markers has been shown to change. Moreover, postpartum inflammation related to endometritis affects the presence and functionality of eMSCs, and prostaglandin E₂ (PGE₂) may be the mediator of such changes. We demonstrated that exposure to PGE₂ in vitro modifies the transcriptomic profile of eMSCs, showing its potential role in the fate of stem cell activation, migration, and homing during pathological uterine inflammation in endometritis and in healthy puerperal endometrium. Farm animal research on eMSCs can be of great value in translational research for certain uterine pathologies and for immunomodulation of local responses to pathogens, hormones, and other substances. Further research is necessary in areas such as in vivo location of the niches and their immunomodulatory and anti-infective properties.

Regulation of inflammatory mediator expression in bovine endometrial cells: effects of lipopolysaccharide, interleukin 1 beta, and tumor necrosis factor alpha

An abnormal uterine environment can influence maternal-fetal communication, conception rate and disrupt normal embryo development, thereby affecting fertility and the reproductive performance of dairy cows. Animal variability means that development of endometrial cell lines with appropriate characteristic are required. We evaluated the effect of an infectious agent (i.e., bacterial lipopolysaccharide; LPS) and proinflammatory mediators (i.e., Interleukin 1 beta; IL-1β, and tumor necrosis factor alpha; TNFα) on inflammatory mediator gene expression and production by bovine endometrial epithelial (bEEL) and stromal (bCSC) cell lines. Expression of CXCL8/IL8, IL1A, IL1B, and IL6 cytokine genes was significantly upregulated in both epithelial and stromal cells when treated with LPS and IL-1β. LPS treatment of epithelial cells (compared with treatment by IL-1β and TNFα) exhibited greater CXCL8/IL8, IL1A, IL1B, and IL6 cytokine gene expression. Whereas, in stromal cells, IL-1β treatment (compared with LPS and TNFα) exhibited greater CXCL8/IL8, IL1A, IL1B, and IL6 cytokine gene expression. Interestingly, bEEL and bCSC cells treated with IL-1β increased IL1B gene expression, suggesting that IL-1β may act unusually in an autocrine-positive feedback loop. Cytokine production was stimulated by these agents in both cell types. We suggest that the characteristics of these two cell lines make them excellent tools for the study of intrauterine environment.