β1-integrin suppresses generation of astrocytes by NSCs derived from the SVZ.

A. NSCs derived from the SVZ show a similar profile of differentiation as those derived from spinal cord. β1-integrin Knock-Out (KO) increases astrocytic differentiation (GFAP - red) without altering neuronal (βIIItubulin - green) or oligodendroglial (O4 -red) differentiation. Scale bar = 20 µm. B. Western blot analysis shows depletion of β1-integrin protein in the β1KO derived NSCs compared with control. C. Quantification of total cell numbers (DAPI) in the cultures of control and β1-integrin null cells analyzed for lineage commitment (D). There was no difference in overall cell numbers (n = 20, p = 0.91). Values are means ± SEM. D. Quantification of cell numbers of different lineages shows a significant increase (*p≤0.046) in astrocytes (56% increase) in the β1-integrin KO group compared with control at 7DIV without any change in neuronal or oligodendroglial differentiation. E. Quantification of mRNA levels by qPCR after 7DIV reveals a significant increase in GFAP mRNA in the β1-integrin KO group compared with control. βIIItubulin and CNPase mRNAs were unchanged.