AIM To determine the value of tests for specific IgA, IgE, and IgG avidity in diagnosing Toxoplasma gondii infection during pregnancy. METHODS In a retrospective study, current serological tests (dye test and three IgM assays with different sensitivities) were compared with immunosorbent agglutination assays (ISAGA) for specific IgA and IgE and an IgG avidity enzyme linked immunosorbent assay...

objective: a descriptive study was carried out to determine the significance of igg-affinity in the serological diagnosis of rubella infections in pregnancy. materials and methods: a total of 92 pregnant women who had never received antirubella vaccines were recruited by simple random selection and did not exceed 24 weeks of gestation were recruited from the antenatal clinics of the university ...

Diagnosis of acute hepatitis A virus (HAV) infection is based on the detection of HAV immunoglobulin M (IgM). However, IgM could be detected due to nonspecific polyclonal activation of the immune system. An avidity test for anti-HAV IgG was developed to distinguish acute infection, where low-avidity antibodies are detected, from immune reactivation. The assay was tested on 104 samples, includin...

INTRODUCTION Cross-sectional methods can be used to estimate HIV incidence for surveillance and prevention studies. We evaluated assays and multi-assay algorithms (MAAs) for incidence estimation in subtype C settings. METHODS We analysed samples from individuals with subtype C infection with known duration of infection (2442 samples from 278 adults; 0.1 to 9.9 years after seroconversion). MAA...

Many pneumococcal capsular polysaccharides (PSs) are similar in structure, and a pneumococcal antibody often binds to all of the PSs with a similar structure. Yet, these cross-reactive antibodies may bind to the structurally related pneumococcal capsular PSs with an avidity too low to be effective. If memory B cells producing such weakly cross-reactive antibodies are elicited with pneumococcal ...

In order to identify pathogenic correlates of refractory rheumatoid arthritis (RA), antibodies against anti-cyclic citrullinated protein (ACPAs) were investigated in RA patients in whom the dysregulated immune system had been ablated by high-dose chemotherapy (HDC) and autologous haematopoietic stem cell transplantation (HSCT). Six patients with refractory RA were extensively characterized in t...

An indirect immunofluorescent assay (Euroimmun AG, Luebeck, Germany) was used to investigate the avidity of immunoglobulin G (IgG), IgM, IgA, and total Ig (IgGAM) antibody responses to severe acute respiratory syndrome coronavirus (SARS CoV) infections. Serial serum samples from eight patients collected during the first, third, and ninth months after the onset of infection were evaluated. It wa...

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 aim of the present study was to compare serological tests (Rose Bengal [RB]; standard agglutination test [SAT]; enzyme immunoassay [EIA] for detection of IgM, IgA, and IgG; and 2-mercaptoethanol [2-ME] test) that are routinely used in patients prediagnosed with different clinical types of brucellosis (acute, subacute, or chronic), and to evaluate the results of the IgG avidity test. Ninety-...