RESUMO
The production of interferon-beta by NB1-RGB fibroblast cells cultured on protein and peptide membranes prepared from silk fibroin, motif peptides of silk fibroin [(AG)(n)] containing arginine-glycine-aspartic acid (RGD) peptide, and Pronectin was investigated. The cell density on various protein and peptide membranes was approximately the same, although the production of interferon-beta depended significantly on the membranes where the cells were cultured. The highest production of interferon-beta was observed when the cells were cultured on (AG)(6)RGD(AG)(7) membranes prepared with hexafluoroacetone (HFA) as the casting solvent. On RGD-containing peptide membranes more centrally located in the peptides, the cells produced more interferon-beta when the peptide membranes were prepared with HFA as the casting solvent. However, there was no enhanced production of interferon-beta by cells on (AG)(6)RGD(AG)(7) membranes prepared with 9 mol/L LiBr or 4.5 mol/L LiClO(4) solution as the casting solvent. Therefore, both the chemical composition and the secondary and higher order structure of the peptide membranes are important for enhanced production of interferon-beta. The blocking of integrin beta(1) on the cells by anti-integrin beta(1) antibody prevented the enhanced production of interferon-beta on (AG)(6)RGD(AG)(7) membranes prepared with HFA. We suggest that the cells must bind to the RGD sequence having the appropriate conformation through their integrin beta(1) for enhanced production of interferon-beta.