Diagnosis of antigenic markers of acute toxoplasmosis by IgG avidity immunoblotting

Ali-Heydari, Siamak; Keshavarz, H; Shojaee, Saeedeh; Mohebali, Mehdi

doi:10.1051/parasite/2013017

Cited by 25 publications

(22 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In our study, the IB pattern analysis showed that, as expected, the positive sera were much more reactive than the negative sera with respect to the number of bands per serum, in both IB assays. Our results are in line with previous reports, where the number of bands recognized by positive sera ranged from 6 to >20 according to the antigens used and to the phase of the disease, while negative sera reacted with 0–8 bands . On the other hand, the number of bands per serum was higher when the ST‐Ag was used as compared to the MT‐Ag.…”

Section: Discussionsupporting

confidence: 92%

See 1 more Smart Citation

Identification of soluble and membrane antigenic markers of acquired toxoplasmosis by immunoblot

Khammari

Saghrouni

Lakhal

et al. 2014

Parasite Immunology

View full text Add to dashboard Cite

The overall performance of quantitative assays in the detection of anti-Toxoplasma IgG is satisfactory, but discrepancies between assays are not uncommon especially when IgG concentrations are close to the limit of detection of the tests. The purpose of our study was to identify soluble and membrane antigens extracted from Toxoplasma gondii tachyzoites by immunoblot to select the most relevant antigenic bands to be used for qualitative serodiagnosis of acquired toxoplasmosis. We selected five relevant bands (98, 36, 33, 32 and 21 kDa) with soluble antigens and four relevant bands (42, 35, 32 and 30 kDa) with membrane antigens which gave high sensitivity and/or specificity in immunodiagnosis. The association on the same blot of at least three of the five relevant bands in the soluble antigen immunoblot showed the highest sensitivity/specificity (97.4%/99.0%, respectively). Our results indicate that immunoblot using soluble tachyzoite extract with simultaneous detection of at least three of the five bands (98, 36, 33, 32 and 21 kDa) represents a valuable test for serodiagnosis of acquired toxoplasmosis and should be further evaluated as a confirmatory test for sera which give discrepant results in quantitative assays.

show abstract

Section: Discussionsupporting

confidence: 92%

“…Whether the 42 kDa antigen is actually a membrane or soluble (cytoplasmic) component remains to be further investigated. In IB‐avidity assay, the 42 kDa band was shown to be a good marker of acute toxoplasmosis . The analysis of our results showed that none of the bands recognized by the tested sera had an absolute specificity.…”

Section: Discussionmentioning

confidence: 69%

Identification of soluble and membrane antigenic markers of acquired toxoplasmosis by immunoblot

Khammari

Saghrouni

Lakhal

et al. 2014

Parasite Immunology

View full text Add to dashboard Cite

show abstract

“…The proteins present in the serum are denatured with a solution of urea. The avidity can be variable during the course of infection [29,30]. In early stages of infection, the values of avidity are low and are increasing with the course of infection [24].…”

Section: Avidity Testmentioning

confidence: 99%

The Laboratory Diagnosis in Toxoplasma Infection

Ramírez¹,

Orozco²,

Ramírez³

2017

Toxoplasmosis

View full text Add to dashboard Cite

The diagnosis of toxoplasmosis is of great importance due to the damage caused by this parasite in immunosuppressed people or in pregnant women, the diagnosis of an active toxoplasmosis represents a sign to initiate a pharmacological treatment immediately. The diagnosis of Toxoplasma can be performed with direct methods through intraperitoneal inoculation of serum or cerebrospinal luid, in susceptible mice evaluating the survival and detection of tachyzoites of biological samples. Indirect methods detecting the IgM and IgG isotypes against Toxoplasma have been the tools mostly used and had leaded to discriminate between an active and acute, from a chronic toxoplasmosis. Molecular methods actually Toxoplasma-DNA identiication by molecular biology tests like the polymerase chain reaction (PCR) allow the direct detection of the parasite. Polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLPs) have been used to identify three strain linages (type I, II and III). Recently, a high-resolution melting method was described to determine the genotype of the infection by Toxoplasma gondii directly from biological samples.

show abstract

“…25,26 The purified recombinant protein, at optimized concentration, was electrophoresed on a 12% SDS-PAGE preparative gel and transferred to a nitrocellulose membrane (0.45 μm, Bio-Rad). The membrane was blocked with protein-free blocking buffer (Pierce, Thermo scientific, MA) at RT for an hour, and then washed with TBST 3 times at 5-min intervals.…”

Section: Igg Avidity Western Blotmentioning

confidence: 99%

Identification, production and assessment of twoToxoplasma gondiirecombinant proteins for use in aToxoplasmaIgG avidity assay

Teh

Amerizadeh

Osman

et al. 2016

Pathogens and Global Health

View full text Add to dashboard Cite

The IgG avidity assay is an important tool in the management of suspected toxoplasmosis in pregnant women. This study aimed to produce new Toxoplasma gondii recombinant proteins and to assess their usefulness in an IgG avidity assay. Toxoplasma positive and negative serum samples were used, the former were categorized into low (LGA) and high (HGA) IgG avidity samples. Immunoblots were performed on 30 T. gondii cDNA clones to determine the reactivity and IgG avidity to the expressed proteins. Two of the clones were found to have diagnostic potential and were analyzed further; AG12b encoded T. gondii apical complex lysine methyltransferase (AKMT) protein and AG18 encoded T. gondii forkhead-associated (FHA) domain-containing protein. The Histagged recombinant proteins, rAG12b and rAG18, were expressed and tested with LGA and HGA samples using an IgG avidity western blot and ELISA. With the IgG avidity western blot, rAG12b identified 86.4% of LGA and 90.9% of HGA samples, whereas rAG18 identified 81.8% of both LGA and HGA samples. With the IgG avidity ELISA, rAG12b identified 86.4% of both LGA and HGA samples, whereas rAG18 identified 77.3% of LGA and 86.4% of HGA serum samples. This study showed that the recombinant antigens were able to differentiate low avidity and high avidity serum samples, suggesting that they are potential candidates for use in the Toxoplasma IgG avidity assay.

show abstract

Diagnosis of antigenic markers of acute toxoplasmosis by IgG avidity immunoblotting

Cited by 25 publications

References 11 publications

Identification of soluble and membrane antigenic markers of acquired toxoplasmosis by immunoblot

Identification of soluble and membrane antigenic markers of acquired toxoplasmosis by immunoblot

The Laboratory Diagnosis in Toxoplasma Infection

Identification, production and assessment of twoToxoplasma gondiirecombinant proteins for use in aToxoplasmaIgG avidity assay

Contact Info

Product

Resources

About