Seroreactivity to and avidity for recombinant antigens in toxoplasmosis.

To improve serodiagnostic methods for the diagnosis of acute toxoplasmosis during pregnancy, a new test system has been developed and evaluated based on the use of recombinant antigens. Five recombinant Toxoplasma gondii antigens (ROP1, MAG1, SAG1, GRA7, and GRA8) were cloned in Escherichia coli, purified, and applied directly onto nitrocellulose membranes in a line assay (recomLine Toxoplasma). A panel of 102 sera from 25 pregnant women with supposed recent toxoplasmosis and from two symptomatic children was compared to a panel of 71 sera from individuals with past infection.

Evaluation of a commercial IgG/IgM Western blot assay for early postnatal diagnosis of congenital toxoplasmosis.

The aim of this study was to evaluate a commercial Western blot IgG/IgM assay for use in the early serological diagnosis of congenital toxoplasmosis. This assay compares the immunological profile of mother and infant and allows differentiation between passive transmitted maternal antibodies and newly synthesized antibodies of the infant within the first 3 months of life. Over a 6-year period (1995-2001), the sera from 169 mothers and their 175 offspring (6 had twins) were examined for specific anti- Toxoplasma gondii IgG, IgM and IgA antibodies with an enzyme-linked immunosorbent assay or an immunosorbent agglutination assay.

Comparative immunoglobulin G antibody profiles between mother and child (CGMC test) for early diagnosis of congenital toxoplasmosis.

Early diagnosis of congenital toxoplasmosis is rendered difficult when specific immunoglobulin M (IgM) and/or IgA antibodies are absent in the blood of the newborn infant. Since maternal IgG antibodies can cross the placenta, determination of IgG antibodies in newborn infants has hitherto not been used routinely for the diagnosis of congenital infection. The aim of this study was to assess the diagnostic usefulness of an immunoblot assay which compares the early IgG profiles between the mother and her child (comparative IgG profile between mother and child; CGMC test) directed against a total cell lysate of Toxoplasma gondii tachyzoites.

Polymorphism of glucose dehydrogenase (GDH, EC 1.1.1.47): formal and population genetic data.

The polymorphism of glucose dehydrogenase (GDH) is demonstrated by isoelectric focusing of leucocyte extracts followed by enzyme staining. Segregation in 52 families with 145 children is consistent with the formal hypothesis of three common alleles, GDH*1, GDH*2 and GDH*3, at an autosomal locus GDH. Allele frequencies from 104 unrelated individuals from southwestern Germany were calculated as GDH*1 = 0.

Linked loci in chromosome 1 (FXIIIB, HF, PEPC) and their variability in Brazilian Indians.

A total of 352 individuals living in seven localities of two Brazilian Indian groups (Macushi and Içana River Indians) were variously studied for coagulation factor XIIIB, human factor H, and a new polymorphism of peptidase C. No significant inter- or intra-tribal differences were found for the FXIIIB alleles, the frequencies varying around 95% for F13B*3 and 5% for F13B*1. Results for HF were heterogeneous, HF*A presenting a much higher frequency among the Macushi (32%) than among the Içana River Indians (9%).