Equine mesenchymal stromal/stem cells (MSCs) are most commonly harvested from bone marrow (BM) or adipose tissue, requiring the use of surgical procedures. By contrast, the uterus can be accessed nonsurgically, and may provide a more readily available cell source. While human endometrium is known to harbor mesenchymal precursor cells, MSCs have not been identified in equine endometrium. This study reports the isolation, culture, and characterization of MSCs from equine endometrium. The presence of MSC and pericyte markers in endometrial sections was determined using immunohistochemistry. Stromal cells were harvested and cultured after separation of epithelial cells from endometrial fragments using Mucin-1-bound beads. For comparison, MSCs were also harvested from BM. The expression of surface markers in endometrial and BM-derived MSCs was characterized using flow cytometry and quantitative polymerase chain reaction. MSCs were differentiated in vitro into adipogenic, chondrogenic, osteogenic, and smooth muscle lineages. Typical markers of MSCs (CD29, CD44, CD90, and CD105) and pericytes (NG2 and CD146) were localized in the equine endometrium. Both endometrial and BM MSCs grew clonally and robustly expressed MSC and pericyte markers in culture while showing greatly reduced or negligible expression of hematopoietic markers (CD45, CD34) and MHC-II. Additionally, both endometrial and BM MSCs differentiated into adipogenic, osteogenic, and chondrogenic lineages in vitro, and endometrial MSCs had a distinct ability to undergo smooth muscle differentiation. We have demonstrated for the first time the presence of cells in equine endometrium that fulfill the definition of MSCs. The equine endometrium may provide an alternative, easily accessible source of MSCs, not only for therapeutic regeneration of the uterus, but also for other tissues where MSCs from other sources are currently being used therapeutically.
Because of their distinct differentiation, immunomodulatory, and migratory capacities, endometrial mesenchymal stromal cells (MSCs) may provide an optimum source of therapeutic cells not only in relation to the uterus but also for regeneration of other tissues. This study reports the fate of endometrial MSCs following intrauterine application in mares. Stromal cell fractions were isolated from endometrial biopsies taken from seven reproductively healthy mares, expanded, and fluorescence labeled in culture. Phosphate-buffered saline (PBS) or MSCs (15 × 106) were autologously infused into each uterine horn during early diestrus and subsequently tracked by fluorescence microscopy and flow cytometry of endometrial biopsies and blood samples taken periodically after infusion. The inflammatory response to cell infusion was monitored in endometrial cytology samples. MSCs were detected in endometrial sections at 6, 12, and 24 h, but not later (7 or 14 days), after cell infusion. Cells were in all cases located in the uterine lumen, never within the endometrial tissue. No fluorescence signal was detected in blood samples at any time point after infusion. Cytology analyses showed an increase in % of polymorphonuclear neutrophils between 1 and 3 h after uterine infusion with either MSCs or PBS and a further increase by 6 h only in mares infused with PBS. In summary, endometrial MSCs were detected in the uterine lumen for up to 24 h after infusion, but did not migrate into the healthy endometrium. Moreover, MSCs effectively attenuated the inflammatory response to uterine infusion. We conclude that endometrial MSCs obtained from routine uterine biopsies could provide a safe and effective cell source for treatment of inflammatory conditions of the uterus and potentially other tissues.
Simulation in veterinary education enables clinical skills practice without animal use. A feline abdominal palpation model was created that allows practice in this fractious species. This study assessed the model and rubric using a validation framework of content evidence, internal structure and relationship with level of training. Content Evidence: Veterinarians accepted this model as a helpful training tool for students (median=4 on five‐point Likert scale). Internal Structure Evidence: G‐coefficients were low for first‐ and second‐year students (0.28 and 0.23), but were acceptable for veterinarians (0.61). Internal consistency values (0.24, 0.42 and 0.67) followed a similar pattern. Thus, scores were more reliable for veterinarians than for the students. Evidence of Relationship with Level of Training: Although level of training impacted reliability, its effect on performance scores was inconsistent. Analysis of variance (ANOVA) identified no differences among the groups of students and veterinarians. However, effect size between first‐ and third‐year students was medium to large (0.62). Effect sizes between the veterinarians and student groups were small. Although the model and rubric appeared valid for experts, modifications would be necessary to generate reliable scores for students. These results allow greater understanding of the needs of students utilising a low‐fidelity model.
1 February 2018 in Journal of Veterinary Medical Education
Obstetrical chain placement requires location of specific landmarks and a certain dexterity that must be practiced. Use of low-fidelity models may not always provide students with a realistic experience. In this study we developed an anatomically correct high-fidelity calf leg model that would serve as a better teaching model for pre-clinical veterinary students than a pre-existing low-fidelity polyvinyl chloride (PVC) model. One hundred and twenty pre-clinical veterinary students were instructed how to use obstetrical chains with a low-fidelity PVC model and the anatomically correct high-fidelity calf leg model. After a 45-minute lab, students were surveyed on their experience with both models. Overall students felt the anatomically correct high-fidelity calf leg model increased accuracy in chain placement and provided more accurate landmarks, a more realistic model, and more real-life scenario training.
1 May 2018 in Journal of Veterinary Medical Education
Gaining experience and dexterity for trans-rectal cattle palpation requires substantial training. Simulation allows students to perform palpation without risks and to obtain feedback, but many believe live cattle palpation is essential. Limited research exists on the proper training method for live animal trans-rectal palpation. This study compared student improvement in laboratory palpation skills when assigned to the same cows versus choosing a cow at random. The hypothesis for the study was that students assigned the same cow, as compared to students choosing a cow at random, would be more accurate at palpation, would learn what structures are present on the ovaries and what size the reproductive tract measures, and would be able to follow the cyclicity of the cow. Cervical diameter, uterine tone, diameter of left and right uterine horns, and ovarian structures were recorded over time. Responses were compared to laboratory instructors' responses and Z-tests for proportions were used to test the differences in percentage correct at each time point for each palpation exercise. Overall the experiment showed that assigning students to certain cows will not improve their trans-rectal palpation training. However, asking students to identify specific landmarks with quantitative measurements did allow for more productive laboratory time and engaged students. The results of the present study also suggest that if there is limited time available for palpation instruction, choosing cows with behavior allowing easy handling is important to the educational process.