Comparison of Sources and Methods for the Isolation of Equine Adipose Tissue-Derived Stromal/Stem Cells and Preliminary Results on Their Reaction to Incubation with 5-Azacytidine.
Authors: Trachsel Dagmar S, Stage Hannah J, Rausch Sebastian, Trappe Susanne, Söllig Katharina, Sponder Gerhard, Merle Roswitha, Aschenbach Jörg R, Gehlen Heidrun
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Researchers investigated optimal methods for harvesting and culturing equine adipose tissue-derived stromal/stem cells (ASCs) as potential building blocks for developing an in vitro cardiac model that reflects the unique electrophysiological properties of the equine heart. Comparing three adipose tissue sources (abdominal, retrobulbar, and subcutaneous) using both collagenase digestion and direct explant culture techniques, the team found that abdominal adipose tissue yielded the highest quantity of viable ASCs, with both isolation methods producing comparable results and confirming appropriate mesenchymal marker expression (CD29, CD44, CD90) and pluripotency markers through flow cytometry and qPCR. When the isolated equine ASCs were exposed to 5-azacytidine—a chemical known to successfully induce cardiomyocyte differentiation in rodent and human cells—the approach failed to trigger cardiac-specific gene expression, with no upregulation of early (GATA4, NKX2-5) or late (TNNI3, MYH6, MYH7) differentiation markers observed at the tested 10 µM concentration over 48 hours. Whilst this research establishes reliable protocols for equine ASC isolation and characterisation, it highlights a significant species-specific difference that prevents direct translation of proven mammalian differentiation strategies to horses, necessitating further investigation into species-appropriate conditions for cardiac differentiation. For equine professionals involved in regenerative medicine applications, these findings underscore the importance of validating cell therapy approaches specifically in equine models rather than assuming cross-species efficacy.
Read the full abstract on PubMed
Practical Takeaways
- •This research does not directly impact equine clinical practice; it is foundational laboratory work developing cell culture models for future cardiac research.
- •Results suggest species-specific differences in stem cell differentiation pathways between equines and other mammals, indicating equine-specific protocols will be needed for therapeutic applications.
- •Current findings indicate significant additional research is required before adipose-derived stem cells can be reliably used for equine cardiac regenerative therapies.
Key Findings
- •Abdominal adipose tissue was the most suitable source for isolating equine ASCs compared to retrobulbar and subcutaneous sources.
- •Both collagenase digestion and direct explant culture methods produced comparable yields of CD45-/CD34-negative mesenchymal stem cells expressing CD29, CD44, and CD90 markers.
- •5-azacytidine exposure (10 µM for 48 hours) failed to induce cardiomyocyte differentiation in equine ASCs, unlike successful induction reported in rats, rabbits, and humans.
- •Neither early (GATA4, NKX2-5) nor late (TNNI3, MYH6, MYH7) cardiomyocyte differentiation markers were upregulated following 5-AZA treatment.