Abstract: This disclosure provides the construction, expression, and selection of the mutated genes that encode novel Trp cage polypeptides with desirable binding properties, as well as the novel Trp cage polypeptides themselves. The substances or targets bound by these novel Trp cage polypeptides may be but need not be proteins or polypeptides. Targets may include other biological or synthetic macromolecules as well as other organic and inorganic substances. Further, targets may also include a single or multiple cell or tissue types. The present invention achieves genetic variants of Trp cage-encoding nucleic acids through controlled random mutagenesis of the nucleic acids yielding a mixture of Trp cage polypeptides that are capable of binding targets.

Abstract: The use of antagonists to JAM-1 Claudin-4 and occludin to open tight junctions. The antagonists include, by way of example antibodies and antibody fragments that bind to the proteins and small interfering nucleic acids that downregulate the mRNA encoding the proteins.