Isolation of SSEA-3-positive mesenchymal stem cells from equine bone marrow and evaluation of their pluripotency.

This paper explores the extraction and evaluation of a specific type of cell, SSEA-3-positive mesenchymal stem cells (also named MUSE cells), from the bone marrow of horses. The research indicated that these cells display pluripotency, the ability to differentiate into various cell types.

Background

• The focus of this research is on mesenchymal stem cells (MSCs). Normally, MSCs have lower pluripotency and limited differentiation potential in comparison to embryonic stem cells.
• However, a small subpopulation of MSCs, called multilineage differentiating stress-enduring cells (MUSE cells), show pluripotency. They express a specific marker, stage-specific embryonic antigen 3 (SSEA-3).

Methodology

• The researchers performed their study on six thoroughbred horses. The MSCs for the study were harvested from the horses’ thoracic vertebrae using ultrasound guidance, ensuring accuracy and precision.
• The harvested MSCs were then sorted into those positive for SSEA-3 (MUSE cells) and those negative for SSEA-3 using a cell sorting device. This allowed the researchers to isolate the specific subpopulation of interest for further examination.

Assessing Pluripotency

• The pluripotency of the separated cell groups was evaluated using immunostaining. Immunostaining is a procedure used to visually detect the presence of specific proteins in cells.
• Cells that show pluripotency typically express the markers NANOG, OCT4, and SOX2. In this study, NANOG and SOX2 were detected in the SSEA-3-negative group, while OCT4 was not detected. The SSEA-3-positive group, on the other hand, expressed all three markers, indicating pluripotency.

Results

• The results revealed that 2.1% of the equine MSCs tested were positive for SSEA-3.
• Importantly, the values for NANOG and OCT4 expression were significantly higher in the SSEA-3-positive group compared to the SSEA-3-negative group. This result further affirmed the pluripotent capacity of MUSE cells.
• The evidence confirms the presence of SSEA-3-positive cells in equine bone marrow-derived MSCs, consistent with the presence of such cells in MSCs in other species, reinforcing the general applicability of the finding.