Antibodies play a central role in prophylaxis against many infectious agents. While neutralization is a primary function of antibodies, the Fc- and complement-dependent activities of these multifunctional proteins may also be critical in their ability to provide protection against most viruses. Protection against viral pathogens in vivo is complex, and while virus neutralization--the ability of...

The gamma interferon assay is used to identify Mycobacterium avium subsp. paratuberculosis-infected animals. It has been suggested that regulatory mechanisms could influence the sensitivity of the test when it is performed with cells from cattle and that the neutralization of interleukin-10 (IL-10) in vitro would increase the gamma interferon responses. To investigate the regulatory mechanisms ...

BACKGROUND Accurate determination of neutralization antibody titers supports epidemiological studies of dengue virus transmission and vaccine trials. Neutralization titers measured using the plaque reduction neutralization test (PRNT) are believed to provide a key measure of immunity to dengue viruses, however, the assay's variability is poorly understood, making it difficult to interpret the s...

A microneutralization assay using an ELISA-based endpoint assessment (ELISA-MN) is widely used to measure the serological response to influenza virus infection and vaccination. We have developed an alternative microneutralization assay for influenza virus using a quantitative reverse transcription PCR-based endpoint assessment (qPCR-MN) in order to improve upon technical limitations associated ...

A novel technique, based on cytotoxicity-neutralization, was developed for the in vitro titration of anti-sheep lymphocyte and anti-sheep macrophage sera. The titres obtained for a number of antisera were compared with those found in an agglutination assay. Anti-lymphocyte sera with a high cytotoxicity-neutralization titre very effectively suppressed the number of circulating lymphocytes in the...

BACKGROUND Novel serological methods provide alternative options for sero-diagnosis, sero-epidemiology and for determining evidence of naturally acquired or vaccine induced immunity. Micro-neutralization tests are currently the gold standard for serological studies of highly pathogenic avian influenza in mammalian species but require handling live virus in a biosafety level (BSL) 3 environment....

Gastrointestinal disease and colonization by Helicobacter pylori were determined in 36 asymptomatic volunteers and 30 symptomatic individuals undergoing endoscopy and biopsy. Serum antibody immunoglobulin G (IgG) and IgA to H. pylori were measured by enzyme-linked immunosorbent assay. Serum antibody to a cytotoxin produced by H. pylori was detected with a neutralization assay. Serum IgG was 95%...