A method for treatment of a subject having an inflammatory disease of the epithelium comprising the step of administering an amount of a composition comprising an isolated bacterial amyloid peptide to said subject. In embodiments, the composition is membrane-free. In embodiments, the composition comprises a curli fibril. In yet further embodiments, the isolated bacterial amyloid peptide is a CsgA polypeptide, a CsgA polypeptide fragment, a CsgB polypeptide or a CsgB polypeptide fragment. Also provided is a method for decreasing epithelium permeability in a tissue of a subject comprising epithelium comprising the step of administering an amount of a composition comprising an isolated bacterial amyloid peptide to the epithelium of the subject. In embodiments, the composition is membrane-free. In further embodiments, the composition comprises a curli fibril. In embodiments, the isolated bacterial amyloid peptide is a CsgA polypeptide, a CsgA polypeptide fragment, a CsgB polypeptide or a CsgB polypeptide fragment.
