Heterogeneity of baseline neural marker expression by undifferentiated mesenchymal stem cells may be correlated to donor age

• qRT-PCR analysis of basal expression of neural markers in MSCs of defined donor age and gender.
• Neural marker expression was normalized to iPSC-derived neural stem cells as positive control.
• Variability of basal neural marker expression in MSCs may be correlated to donor age.
• Baseline levels of neural marker expression in MSCs may be a measure of neurogenic potential.

Previous studies reported much heterogeneity in baseline neural marker expression by undifferentiated mesenchymal stem cells (MSCs) of animal and human origin, which could confound reproducibility of neural differentiation experiments with MSCs. Nevertheless, basic donor characteristics such as age and gender were unspecified in these previous studies; and relative levels of baseline neural marker expression amongst primary MSCs of different tissue and donor origin have not been compared by quantitative real-time polymerase chain reaction (qRT-PCR) analysis, which is the focus of this study. The results showed that amongst a mixed group of primary adipose and bone marrow-derived MSCs (12–50 years), the observed variability in baseline neural marker expression may be correlated to donor age. Adipose-derived MSCs from the youngest donor (male, 12 years old) displayed the highest expression of all four early neural markers (Pax6, Nestin, Musashi 1 and βIII-tubulin), and three out of four mature neural markers (NCAM, NSE and NFM) analyzed by qRT-PCR. Conversely, adipose MSCs of the oldest donor (female, 50 years old) displayed the lowest expression of three out of four early neural markers (Pax6, Musashi 1 and βIII-tubulin), and three out of four mature neural markers (MAP2, NCAM and NSE) analyzed by qRT-PCR.