Development and Comparison of Enzyme Immunoassays for Diagnosis of Chagas' Disease Using Fixed Forms of
            <i>Trypanosoma cruzi</i>
            (Epimastigotes, Amastigotes, and Trypomastigotes) and Assessment of Antigen Stability for the Three Assays

Berrizbietia, Mariolga; Ndao, Momar; Gottschalk, Marcelo; Aché, Alberto; Vásquez, Fabio; Lacouture, Sonia; Medina, Mehudy; Ward, Brian J.

doi:10.1128/jcm.42.4.1766-1769.2004

Cited by 12 publications

(18 citation statements)

References 30 publications

(18 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The mean age of the infected individuals was 47 years (range 34 to 78 years): all recognized the vector and 27% reported infestation of their houses. All of these samples were also tested by an ELISA using fixed epimastigote forms of T. cruzi (Berrizbietia et al 2004). Seven samples were positives by ELISA (one discordant result).…”

Section: Discussionmentioning

confidence: 99%

“…The average OD obtained was only accepted when the coefficient of variation within and between plates was below 15%; otherwise, samples were retested. Results from healthy control sera were used to establish cutoff values that yielded optimal sensitivity and specificity results for each assay (Berrizbietia et al 2004). …”

Section: Mabamentioning

confidence: 99%

“…Fixed epimastigote-based EIA Fixed epimastigotes test assay was performed as previously described (Berrizbietia et al 2004). Briefly, polystyrene 96-well plates (Immulon 2, Thermo Labsystems, Franklyn, MA) were coated overnight with 100 μL per well of fixed epimastigotes T. cruzi antigen (1×10 6 parasites per milliliter) at 4°C in 1 M sodium carbonate buffer (pH 9.6).…”

Section: Mabamentioning

confidence: 99%

See 2 more Smart Citations

85-kDa protein of Trypanosoma cruzi purified by affinity chromatography used in the multiple antigen binding assay (MABA) for the diagnosis of T. cruzi infection in a Venezuelan rural community

et al. 2010

Self Cite

View full text Add to dashboard Cite

No ideal test exists for Chagas' disease, and better diagnostic strategies are needed. We determined the diagnostic utility of an 85-kDa Trypanosoma cruzi protein in a multiple antigen binding assay (MABA). A standardized MABA test based on concentrated trypomastigote excretory-secretory antigen (TESA) and an 85-kDa purified protein showed 100% sensitivity and specificity. In field conditions, 6/66 individuals tested in a region not thought to be endemic (Rio Brito) were identified as seropositive for T. cruzi infection with our MABA test. In parallel, an enzyme-linked immunosorbent assay based on fixed epimastigotes detected 7/66 positives, which were independently confirmed. These data suggest that the 85-kDa and TESA proteins could be used in the MABA format as a complementary tool for the diagnosis of latent Chagas' disease. High anti-T. cruzi antibody detection rates, poor knowledge of Chagas' disease and its vector, and the demonstration of infected vectors in the study community all suggest a significant risk of reemergence of T. cruzi infection in this region of Venezuela.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Mabamentioning

confidence: 99%

Section: Mabamentioning

confidence: 99%

See 1 more Smart Citation

85-kDa protein of Trypanosoma cruzi purified by affinity chromatography used in the multiple antigen binding assay (MABA) for the diagnosis of T. cruzi infection in a Venezuelan rural community

et al. 2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…Epimastigotes were collected during the logarithmic growth phase, as previously described, and washed three times in 1 M PBS (pH 7.4) by centrifugation at 850 ϫ g for 15 min at 4°C. The trypomastigotes for infection were then prepared as previously described (38) by infecting Vero cell monolayers (ATCC CCL-81) with the epimastigotes, harvesting the supernatant after 7 days, purifying the trypomastigotes in a column, and counting them in a Neubauer chamber.…”

Section: Figmentioning

confidence: 99%

Reversible Cysteine Protease Inhibitors Show Promise for a Chagas Disease Cure

Ndao

Beaulieu

Black

et al. 2014

Antimicrob Agents Chemother

Self Cite

View full text Add to dashboard Cite

The cysteine protease cruzipain is essential for the viability, infectivity, and virulence of Trypanosoma cruzi, the causative agent of Chagas disease. Thus, inhibitors of cruzipain are considered promising anti-T. cruzi chemotherapeutic agents. Reversible cruzipain inhibitors containing a nitrile "warhead" were prepared and demonstrated 50% inhibitory concentrations (IC 50 s) as potent as 1 nM in baculovirus-generated cruzipain enzyme assays. In epimastigote and intracellular amastigote in vitro assays, the most potent compounds demonstrated antiparasitic behavior in the 5 to 10 M IC 50 range; however, trypomastigote production from the amastigote form was ϳ90 to 95% inhibited at 2 M. Two key compounds, Cz007 and Cz008, with IC 50 s of 1.1 and 1.8 nM, respectively, against the recombinant enzyme were tested in a murine model of acute T. cruzi infection, with oral dosing in chow for 28 days at doses from 3 to 50 mg/kg of body weight. At 3 mg/kg of Cz007 and 3 mg/kg of Cz008, the blood parasitemia areas under the concentration-time curves were 16% and 25% of the untreated group, respectively. At sacrifice, 24 days after immunosuppression with cyclophosphamide, parasite presence in blood, heart, and esophagus was evaluated. Based on negative quantitative PCR results in all three tissues, cure rates in surviving animals were 90% for Cz007 at 3 mg/kg, 78% for Cz008 at 3 mg/kg, and 71% for benznidazole, the control compound, at 50 mg/kg.

show abstract

“…All tests were done simultaneously using the same batch of tests and on the same machine to reduce random variability in measurements. In Montreal, all 2008 and 2011 samples were simultaneously tested with an in-house ELISA using fixed forms of Trypanosoma cruzi (epimastigotes, amastigotes, and trypomastigotes) as described elsewhere [15]. The cut-off value of the optical density (OD) for negativity of the Biokit Bioelisa Chagas® was 0.320, as instructed by the manufacturer and 0.4 for the in-house ELISA.…”

Section: Methodsmentioning

confidence: 99%

Serological and parasitological response in chronic Chagas patients 3 years after nifurtimox treatment

et al. 2013

Self Cite

View full text Add to dashboard Cite

BackgroundWith declining vectorial transmission, Chagas disease predominantly affects adults nowadays. The efficacy of nifurtimox in the chronic phase in adult patients is poorly known, particularly in regions where there is no risk of reinfection. Recommendations for treatment outcome assessment rely on serological follow-up. We evaluated the serological and parasitological response to nifurtimox in a cohort of adult patients three years post-treatment in Switzerland.MethodsPatients treated with nifurtimox in 2008 during a cross-sectional study in Geneva, Switzerland, were contacted for follow-up in 2011. Two ELISAs and a rapid immunochromatographic test were used to test 2008 and 2011 serum samples simultaneously. In addition, conventional and real-time PCR were performed on 2011 samples.ResultsThirty-seven (84.1%) of 44 eligible patients, predominantly female, middle-aged, Bolivians at the indeterminate stage, were enrolled. All 2011 ELISA and immunochromatographic tests were positive. Twenty-eight (75.7%) patients presented a lower optical density (OD) in 2011 compared to 2008. This OD difference was significant in both commercial (P < 0.001) and in-house (P = 0.002) ELISAs. Agreement between the two ELISAs was low (Kappa = 0.469). All patients had negative conventional PCR results but one (2.7%) was positive with real-time PCR.ConclusionOur results highlight the inadequacy of serology for assessing response in adults, three years after treatment. In our cohort, 97.3% had results that could either indicate treatment failure or persistant humoral response despite treatment. The lack of accurate early post-treatment tests of cure prevents appropriate patients information and councelling. New follow-up tests are needed to assess treatments efficacy given the large adult population in need of antiparasitic therapy.

show abstract

Development and Comparison of Enzyme Immunoassays for Diagnosis of Chagas' Disease Using Fixed Forms of Trypanosoma cruzi (Epimastigotes, Amastigotes, and Trypomastigotes) and Assessment of Antigen Stability for the Three Assays

Cited by 12 publications

References 30 publications

85-kDa protein of Trypanosoma cruzi purified by affinity chromatography used in the multiple antigen binding assay (MABA) for the diagnosis of T. cruzi infection in a Venezuelan rural community

85-kDa protein of Trypanosoma cruzi purified by affinity chromatography used in the multiple antigen binding assay (MABA) for the diagnosis of T. cruzi infection in a Venezuelan rural community

Reversible Cysteine Protease Inhibitors Show Promise for a Chagas Disease Cure

Serological and parasitological response in chronic Chagas patients 3 years after nifurtimox treatment

Contact Info

Product

Resources

About