Identification of HCV Core Mimotopes: Improved Methods for the Selection and Use of Disease-Related Phage-Displayed Peptides

Abstract

Disease-specific epitope discovery from random peptide libraries displayed on phage using sera from patients involves a number of screening steps with many immune and non-immune sera. To rapidly identify mimotopes of the human hepatitis C virus (HCV) core protein, we have used an anti-core human monoclonal antibody (mAb; B12.F8) as a probe in screening phage that were affinity-selected using a serum from an HCV infected patient. Three different positive phage were isolated displaying low or no homology with the natural antigen, but which still efficiently bound to the antigen binding site of the B12.F8 antibody. Testing the reactivity of these phage with forty-five sera from HCV infected patients showed that antibodies recognizing them are present in more than 80% of this population. These antibodies showed distinct fine specificity, as they bound the selected phage in a mutually exclusive fashion. Co-expression of two mimotopes in the same cells led to chimeric particles which were recognized by antibodies of different specificity. These data provide novel information on the potential use of the phage display technology for the characterization of antibody specificity as well as disease diagnosis and prevention.

Generation of infectious and transmissible virions from a GB virus B full-length consensus clone in tamarins

“…It is not known, however, whether humoral immune response to these non-structural antigens plays a role in limiting virus replication ; moreover, a correlation between seroconversion and clearance was not observed in any animals of this study. Attempts to detect antibodies against GBV-B structural antigens (core protein) gave negative results (data not shown), in spite of expectations based on the known HCV core antigenicity (Pujol et al, 1996 ;Tafi et al, 1997) and on some data published about GBV-B (Pilot-Matias et al, 1996).…”

Epitopes and Mimotopes Identification Using Phage Display for Vaccine Development against Infectious Pathogens

“…Through this screening process, three distinct phagotopes were identified. These phagotopes demonstrated recognition not only by an anti-core human monoclonal antibody but also by 45 different sera derived from individuals who were infected with HCV [ 74 ]. This highlights their potential as valuable tools for diagnostic and therapeutic applications.…”

Isolation of Neurocysticercosis-Related Antigens from a Genomic Phage Display Library of Taenia solium

“…To improve the accuracy of diagnostic phage-based ELISA, it may be necessary to create, as mentioned above, an antigen cocktail containing several phage clones. Alternatively, due to the presence of anti-M13 antibodies in human sera, 27 the generation of antigens identified in this study as phage-free peptides/proteins probably will result in more sensitive and accurate ELISA. 28…”