Sprague-Dawley (SD) Rat Mesenchymal Stem Cells

Rat mesenchymal stem cells (rMSCs) are multipotent stromal cells isolated from bone marrow. rMSCs display a characteristic fibroblast-like, spindle-shaped morphology in culture. They form colony-forming unit-fibroblasts (CFU-F) and undergo robust expansion in standard media supplemented with fetal bovine serum, while maintaining stability through multiple passages. Immunophenotypically, rMSCs are positive for CD29, CD44, CD73, CD90, and CD105, and negative for hematopoietic markers CD34, CD45, and CD11b.

A fundamental advantage of rMSCs is their proven trilineage differentiation potential under defined induction conditions. Beyond mesodermal lineages, rMSCs exhibit transdifferentiation toward neural and endothelial phenotypes, underscoring their versatility. The rat model itself confers distinctive translational value: rats are physiologically, metabolically, and anatomically closer to humans than mice, with larger organ dimensions that facilitate surgical manipulation, implantation, and serial blood sampling. rMSCs are therefore extensively employed in preclinical studies modeling myocardial infarction, spinal cord injury, stroke, acute kidney injury, osteoarthritis, and hepatic fibrosis. Their strong immunomodulatory capacity-via paracrine secretion of TGF-β, IL-10, and PGE2-enables allogeneic use without major rejection. Furthermore, rMSCs are readily engineered with lentiviral or CRISPR/Cas9 vectors for gene overexpression or knockdown, and can be labeled with GFP or luciferase for non-invasive tracking. Despite inherent donor heterogeneity, standardized isolation protocols yield reproducible populations, cementing rMSCs as an indispensable ex vivo and in vivo tool for mechanistic interrogation and cell-based therapeutic development.