Improved physical and biochemical features of a collagen membrane by conjugating with soluble egg shell membrane protein.

Soluble egg shell membrane protein (SEP) prepared from the egg shell membrane by performic acid oxidation and pepsin digestion was applied to prepare a membrane conjugated with pepsin-solubilized collagen (PSC) by cross-linking with water-soluble carbodiimide. SEP enabled a conjugated membrane to be constructed with a well-developed network structure having thicker collagen fibrils and higher stability than the PSC membrane alone, as indicated by reduced solubility and collagenase-digestion, increased denaturation temperature, and superior flexibility. The SEP-PSC membrane (SEP:PSC of 1:1, w/w) had lower sweatiness than the PSC membrane. Fibroblasts and keratinocytes adhered to the SEP-PSC-coated wells (SEP:PSC of 1:10, w/w) as a fundamental model of an artificial skin similar to that to the PSC-coated wells due to similar expression level of several cell-adhesion proteins. An SEP-PSC coating accelerated the cell growth of fibroblasts, whereas the cell growth of keratinocytes did not change, or decreased slightly due to more rapid differentiation indicated by a more substantial expression of differentiation marker proteins than a PSC-coating without SEP.