Overview

Improving diagnostics and treatments for infectious diseases with peptide libraries

In general, for animal viruses to replicate they must penetrate the host cell to hijack the host replication machinery. For this to occur, the virus first recognizes and binds to specific receptors on the cell surface, resulting in fusion of the viral envelope with the cell membrane and subsequent endocytosis. At this point an immune response can be stimulated when the infected cell displays viral particles via MHC I receptors. Upon recognition by a CTL, the infected cell can then be destroyed, or antibodies can be synthesized against the virus for subsequent agglutination. While the immune system can successfully eliminate viral infections in this manner, there are many viruses that escape the immune system altogether. Peptide libraries, which are comprised of systematic combinations of antigenic peptide fragments, can accelerate the discovery and design of vaccines for these types of viral diseases.

Discovery of mimotopes using peptide libraries

Mimotopes, or peptides that mimic an epitope, are commonly used to develop vaccines and antibodies against multiple types of viral diseases. Because of the structural similarity, these peptides will stimulate an immune response and be recognized by the same antibodies. Peptide libraries are almost exclusively used to find these mimotopes, since they drastically reduce the amount of time needed for screening. Once the epitopes have been identified, they can be used to develop serodiagnostics or identify antibodies that might be used for vaccine development. Recent studies have applied this research to epitope discovery for Lyme Disease, Hepatitis C, and West Nile Virus among others.