This article describes the standardization and evaluation of an in-house specific IgG avidity ELISA for distinguishing recent primary from long-term human cytomegalovirus (HCMV) infection. The test was standardized with the commercial kit ETI-CYTOK G Plus (Sorin Biomedica, Italy) using 8 M urea in phosphate-buffered saline to dissociate low-avidity antibodies after the antigen-antibody interact...

Sera from 20 cases of toxoplasmic lymphadenopathy were examined by an enzyme linked immunosorbent assay toxoplasma IgG avidity (ELISA) at two laboratories. The results obtained were largely in agreement and showed that sera from patients with acute infection had low avidity IgG (30% or less), whereas sera from patients with chronic infection had high avidity IgG (40% or more). It is suggested t...

T cells expressing high avidity T-cell receptors (TCRs) have been shown to mediate superior therapeutic effects. A novel koff-rate assay allows for the quantitative and reproducible assessment of the avidity of TCRs for their ligands directly on living T cells, ex vivo. This assay might facilitate the selection of T cells with an optimal avidity for their target, hence favoring the development ...

The reference method for immunoglobulin G (IgG) avidity determination includes reagent-consuming serum titration. Aiming at better IgG avidity diagnostics, we applied a logistic model for the reproduction of antibody titration curves. This method was tested with well-characterized serum panels for cytomegalovirus, Epstein-Barr virus, rubella virus, parvovirus B19, and Toxoplasma gondii. This ap...

The efficacy of antigen-specific CD8(+) CTLs depends not only on the quantity of CTLs generated but also perhaps, more importantly, on the avidity of the CTLs. To date, however, no strategy has been shown to preferentially induce higher-avidity human CTLs. In the present study, antigen-presenting cells (APC) generated from human peripheral blood mononuclear cells were infected with a recombinan...

The objective of this study is primarily to compare the performance of the VIDAS(®) Measles immunoglobulin (Ig)G assay to that of two other serological assays using an immunoassay technique, Enzygnost(®) Anti-measles Virus/IgG (Siemens) and Measles IgG CAPTURE EIA(®) (Microimmune). The sensitivity and the agreement of the VIDAS(®) Measles IgG assay compared to the Enzygnost(®) Anti-measles Viru...

OBJECTIVE To determine HSV-2 seroprevalence, risk factors, and antibody avidity among a sample of Mexican pregnant women. MATERIAL AND METHODS The avidity test was standardized with different urea concentrations and incubation times; the cut-off point was calculated to determine the low avidity (early infection). IgG antibodies against HSV-2 were detected from pregnant and postpartum women fr...

The purpose of this study was to determine if the SV40-transformed murine macrophage cell line IC-21 is a suitable model to study the selective high avidity binding of tumor cells by subpopulations of activated macrophages. IC-21 macrophages bound P815, RBL5, and EL-4 murine tumor cells with high avidity, as measured by the inverted centrifugation method. Tumor binding by IC-21 macrophages was ...

Cytomegalovirus (CMV) infection is common among infants of HIV-infected mothers in resource-limited settings. We examined the prevalence and timing of infant CMV infection during the first year of life using IgG antibody and avidity among HIV-exposed infants in Malawi and correlated the results with the presence of detectable CMV DNA in the blood. The Breastfeeding, Antiretrovirals and Nutritio...

BACKGROUND Toxoplasmosis is well known as an important infection in pregnant women. Although many serologic methods are available, diagnosis of early Toxoplasmosis may be extremely difficult. OBJECTIVE To detect the Toxoplasma IgG antibodies developed at the early stage of infection in pregnant women. METHODS 225 pregnant women, who were in the 2nd to 4th month of their pregnancy, enrolled ...