Differentiation of ST2
bone marrow stromal cells treated with the LRAP signaling molecule
to activate the Wnt pathway and weak β-sheet PA assemblies.
Real time quantitative RT-PCR analysis of osteoblast cell marker gene
mRNA expression and mineral deposition by ST2 cells. (A) Two days
after osteo-induction, RNA was isolated for qRT-PCR analysis of osteoblast
marker genes: Runx2, Osx, Dlx5, and type I collagen (coll. I). Data
is expressed as a relative fold increase in gene expression of conditions
containing weak β-sheet PA assemblies normalized to conditions
with LRAP but lacking PA assemblies. ***p < 0.001,
**p < 0.01, nonparametric t-test
comparing to conditions with the same LRAP concentration but lacking
PA nanofibers (n = 3). (B) Two weeks after bone induction,
mineral deposition was assayed with Alizarin Red staining and (C)
quantified. *p = 0.018, nonparametric t-test comparing conditions with the same concentration of LRAP but
lacking PA nanofibers (n = 3). Data is represented
as a relative increase in mineral deposition for cells treated with
the weak β-sheet PA nanofibers normalized to the LRAP only treatment
baseline. OM: Osteogenic media without LRAP.