B cell epitope mapping using synthetic peptides.

Synthetic peptides are used for identification of functional B cell epitopes in antibody preparations. ELISA-type assays are used to identify sequences of proteins comprising antibody-binding regions. This unit describes three peptide display formats.

Comparison between env-specific T-cell epitopic responses in HIV-1-uninfected adults immunized with combination of ALVAC-HIV(vCP205) plus or minus rgp160MN/LAI-2 and HIV-1-infected adults.

In this study, we investigated the CD4 T-helper response induced by ALVAC-HIV(vCP205) +/- rgp160MN/LAI-2 using a series of 15 overlapping amino acid peptides spanning the entire gp160MN/LAI-2 antigen. CD4 Env-specific T-cell lines were established from three groups of HIV-1-negative HIV vaccine recipients: vCP205 + gp160MN/LAI-2, vCP205 only, and gp160MN/LAI-2 only. CD4 Env-specific T-cell lines established from individuals who received the prime-boost vCP205 + rgp160MN/LAI-2 generated strong and broad T-helper responses scattered across the Env sequence, whereas Env-specific T-cell lines from individuals receiving the vCP205 vaccine alone generated reactivity to only a few peptides.

A panel of MHC class I restricted viral peptides for use as a quality control for vaccine trial ELISPOT assays.

Vaccines in general and HIV vaccines in particular are focusing ever more on the induction of cellular immunity specifically the generation of cytotoxic T cells (CTL). As progress is made towards developing a safe and effective HIV vaccine, there is a need for a robust, sensitive and reproducible assay to evaluate vaccine-induced cellular immunogenicity in Phase II/III trials. The enzyme-linked immunospot (ELISPOT) assay fits these criteria and is a technology that is readily transferable and amenable to high-through-put screening.

Selective increases in HIV-specific neutralizing antibody and partial reconstitution of cellular immune responses during prolonged, successful drug therapy of HIV infection.

Because the immune response to HIV depends on viral gene expression, we examined the HIV-specific immune responses in persons whose viral load after highly active antiretroviral therapy (HAART) was <400 on at least 3 occasions over a 12-month interval. Eleven patients were identified. While there was little change in mean HIV-binding antibody (Ab) titers in this group, two persons mounted increases in HIV envelope-specific binding antibody.

Functional analysis of hepatitis C virus E2 glycoproteins and virus-like particles reveals structural dissimilarities between different forms of E2.

Structure-function analysis of the hepatitis C virus (HCV) envelope glycoproteins, E1 and E2, has been difficult due to the unavailability of HCV virions. Truncated soluble forms of E2 have been used as models to study virus interaction with the putative HCV receptor CD81, but they may not fully mimic E2 structures on the virion. Here, we compared the CD81-binding characteristics of truncated E2 (E2(660)) and full-length (FL) E1E2 complex expressed in mammalian cells, and of HCV virus-like particles (VLPs) generated in insect cells.