Production of DNA, GAG and HYP and collagen mRNA expression during chondrogenic MSC differentiation.

<div><p>The upper graph A shows the changes in total DNA content per bead (or per pellet, respectively) during the differentiation and the increase of proteoglycans and hydroxyproline as a sign of extra cellular matrix production. Both pellet cultures and alginate bead cultures show an increase in GAG, but only in alginate beads, also collagen is produced and retained. Shown is the mean of three samples per animal (n=6) +/- standard error of the mean (SEM).</p> <p>The lower graph B shows the fold-increase (mean +/- SD) of collagen mRNA, compared to undifferentiated MSCs kept in monolayer in expansion medium for 3 weeks. The bars compare alginate beads with and without TGF-β1 vs. pellet cultures with and without TGF-β1. Alginate beads with TGF-β1 show the highest increase in Col II mRNA expression, indicating that the culture system is well suited for chondrogenic differentiation of the MSCs.</p>