Serum-Free Culture of Human Mesenchymal Stem Cell Aggregates in Suspension Bioreactors for Tissue Engineering Applications

Figure 6

IHC of collagen deposition in aggregates harvested on culture day 12. Sections were either incubated with the primary antibody (positive) or had the primary antibody omitted (negative). (a) IHC staining of collagen type I and collagen type II in the aggregates formed within the suspension bioreactors. (b) Collagen I and (c) collagen II quantification depicted as normalized positive staining (image pixels) in sections incubated with the primary antibody (positive), had the primary antibody omitted (negative), and the mean difference (mean ) between these two. DAB signal intensity quantified in IHC images by ImageJ and an open source IHC quantification plugin [46]. Significance differences are denoted by the presence of asterisks (, ).

(a)

(b)

(c)