FIG. 7.

ECM IHC in 3D slice cultures demonstrates the initial binding preferences of BMSC and ASC to the decellularized lung matrix. (A–D) A comparative analysis of these images suggests that association with collagen type I is marginal at 24 h for both cell types; however, at 7 days, the ASC show some association with areas identified as being dense in collagen type I and display a cell body-like silhouette of positive staining (D, white arrows). (I–J) BMSC seem to be associated with laminin dense areas by day 7 with cell body-like positive staining (J, white arrows) but do not initially show any particular preference for this protein. (K, L) At 24 h, ASC show close association with laminin-dense areas, and this association is reduced by day 7. No change in ECM-specific association or cell body-like staining is evident for the ubiquitous collagen IV (E–H) or the predominantly vascular-associated fibronectin (M–P) at 24 h or at 7 days after seeding of either cell type. (Q–T) Secondary antibody-only (Q, R) and IgG isotype (S, T) controls validate staining specificity. Note that (A–P)=400× magnification and (Q–T)=100× magnification. Insets represent a 2× enlarged portion of each field to show fine details. Color images available online at www.liebertpub.com/tea