FIGURE 9.

Attachment and cytoarchitecture of SH-SY5Y cells on collagen and amyloid fibrils. A, cytoskeletal organization and focal adhesion formation in SH-SY5Y cells on collagen and amyloid fibrils. Phalloidin (green), FAK (red), and DAPI (blue) were used to visualize F-actin, focal adhesions, and nuclei, respectively. Scale bar, 20 μm. B, cytoskeletal organization and focal adhesion formation in SH-SY5Y cells on kassinin and Sub P monomers. Phalloidin (green), FAK (red), and DAPI (blue) staining showing organization of F-actin, focal adhesions, and nuclei in the immunofluorescence study, respectively. Scale bar, 20 μm. Perinuclear staining of FAK was observed in cells grown on both monomers of kassinin and Sub P. C, quantitative analysis of the size and number of FAK-positive focal adhesions. The higher number and larger size of focal adhesion complex are shown in the case of kassinin and Sub P fibrils relative to collagen. Statistical significance (*, p < 0.05) was determined by Student's t test. D, β1 and β3 integrin expression profile in SH-SY5Y cells cultured on uncoated, collagen-coated, and kassinin fibril-coated glass coverslips. The mRNA expression of β1 integrin was highest in cells cultured on kassinin fibrils. E, localization of β1 integrin of cells grown on uncoated glass, collagen, and kassinin amyloid surfaces. Scale bar, 20 μm. Increased β1 integrin staining and clustering (white arrows) were found in cells cultured on amyloid surfaces. F, clustering of β1 integrins in SH-SY5Y cells (quantified from fluorescence intensity) is shown to be higher on kassinin substrates compared with collagen. Error bars, S.D. **, p < 0.005.