Serum samples, 100 in the total number, were collected from different laboratories in Tehran, Iran and tested for anti-Toxoplasma specific IgG and IgM antibodies using indirect immunofluorescent antibody test (IFAT). Using the IgG (chronic) and IgM (acute) positive samples, the IgG avidity test was performed by ELISA in duplicate rows of 96-well microtiter plates. One row was washed with 6 M ur...

Congenital toxoplasmosis is associated with important morbidity and mortality. Since vertical transmission of Toxoplasma gondii can occur in acute cases, antenatal screening for recent infections is vital. Accurate determination of acute toxoplasmosis requires a combination of immunoassays, usually not routinely applied for screening purposes. This study evaluated the anti-T. gondii (IgG+IgM)/I...

Toxoplasma gondii causes severe fetal disease during acute infection in pregnant women, thus demanding early diagnosis for effective treatment and fetus preservation. Fetal tests are inefficient and risky, and diagnosis is based on maternal IgM serology, which had weak screening ability due to increased sensitivity, with alternative IgG avidity tests. Here, we performed ELISA and avidity assays...

A total of 52 serum samples from patients with symptoms suggestive of tick-borne encephalitis virus (TBEV) infection and positive IgM and/or IgG antibodies were tested for IgG avidity. Acute/recent TBEV infection was confirmed by low/borderline avidity index (AI) in 94.8% IgM positive/IgG positive samples, while in 5.2% high AI was found indicating persisting IgM antibodies. Majority of IgM neg...

In the present study, anti-Leishmania immunoglobulin G (IgG) avidity was used to estimate the approximate time of disease manifestation. Significant differences (P < 0.0001) were found between the levels of anti-rKE-16 IgG avidity in leishmaniasis patients with recent and chronic diseases. More than 76% of patients with an illness duration of less than 6 months had avidity of less than 70%, 94%...

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...

Acute Toxoplasma gondii infection in early pregnancy carries the risk of transmitting the infection to the fetus with serious sequelae. However, serological testing for IgG/IgM anti-Toxoplasma antibodies may fail to differentiate between a recent and past infection. Two hundred and twenty-four Kuwaiti women in their first trimester were screened for IgG/IgM antibodies by the Vitek Immuno Diagno...

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 objective of this work was to develop an antibody-specific immunoglobulin G (IgG) avidity assay to discriminate between acute and latent phases of Toxoplasma gondii infection by using recombinant antigens. One hundred twenty-one serum samples from women who developed IgG antibodies against Toxoplasma during pregnancy were used. The IgG avidities of antibodies directed against epitopes carri...

The role of antibody avidity in allergy is poorly understood and there is no existing literature describing antibody avidity in food allergy. The main aim of this study was to investigate IgE and IgG avidity to a total peanut protein extract (TPPE) and purified Ara h 2 in a group of well-characterized peanut allergic individuals. Forty peanut allergic patients underwent a double-blind placebo-c...