IgG Avidity ELISA Test for Diagnosis of Acute Toxoplasmosis in Humans

Rahbari, Amir Hossien; Keshavarz, H; Shojaee, Saeedeh; Mohebali, Mehdi; Rezaeian, Mostafa

doi:10.3347/kjp.2012.50.2.99

Cited by 38 publications

(31 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The evaluation of IgG avidity has been widely used in the routine diagnosis of various infectious diseases, not only toxoplasmosis (LAPPALAINEN; RAHBARI et al, 2012), but also rubella (REIS et al, 2004), varicella (ONO et al, 2004KNEITZ et al, 2004) and cytomegalovirus (BONALUMI et al, 2011), been very useful for assessing seroconversion during gestation (BOBIC et al, 2009). The avidity of IgG antibody against TES is potentially useful for immunodiagnostics of toxocariasis and should be included in the complementary diagnosis when IgM levels remain high throughout the infection.…”

Section: Resultsmentioning

confidence: 99%

Determination of IgG avidity in BALB/c mice experimentally infected with Toxocara canis

Schoenardie

Scaini

Ávila

et al. 2014

Rev. Bras. Parasitol. Vet.

View full text Add to dashboard Cite

Toxocariasis is a zoonotic disease in that IgM titers can remain high for long periods making difficult to determine the stage of the disease. The aim of this study is to investigate the applicability of indirect ELISA, associated with urea, to discriminate between the acute and chronic toxocariasis. IgG avidity was evaluated in 25 BALB/c mice experimentally infected with 1000 Toxocara canis eggs. Blood samples were collected, and sera treated with 6 M urea and assayed by ELISA every two weeks. The percent IgG avidity was determined using the mean absorbance of sera treated with urea, divided by the mean absorbance of untreated sera. In the first 15 days post-inoculation, was observed a low percentage, between 7.25 and 27.5%, IgG avidity, characteristic of an acute infection. After 60 days of infection, all the mice showed between 31.4 and 58% IgG avidity, indicating a chronic infection.Keywords: Visceral larva migrans, toxocariasis, acute and chronic infections, ELISA. ResumoA toxocaríase é uma zoonose na qual os títulos de IgM podem permanecer elevados por longos períodos, tornando difícil a determinação do estágio em que a doença se encontra. O objetivo deste estudo foi investigar a aplicabilidade de um teste indireto de ELISA, associado com ureia, para fazer a discriminação entre as fases aguda e crônica da toxocaríase. A avidez de IgG foi avaliada em 25 camundongos BALB/c experimentalmente infectados com 1000 ovos embrionados de Toxocara canis. A cada duas semanas, amostras de sangue foram coletadas, o soro tratado com ureia 6M e realizado o ensaio pela técnica de ELISA. O percentual de avidez de IgG foi determinado, usando-se a média das absorbâncias dos soros tratados com ureia dividida pela média das absorbâncias dos soros não tratados. Nos primeiros 15 dias pós-inoculação, foi observado um baixo percentual de avidez de IgG, entre 7,25 e 27,5%, característico da fase aguda da infecção. Após 60 dias de infecção, todos apresentaram avidez de IgG entre 31,4 e 58%, indicando a fase crônica da infecção.Palavras-chave: Larva migrans visceral, toxocaríase, infecção aguda e crônica, ELISA.

show abstract

Section: Resultsmentioning

confidence: 99%

Determination of IgG avidity in BALB/c mice experimentally infected with Toxocara canis

Schoenardie

Scaini

Ávila

et al. 2014

Rev. Bras. Parasitol. Vet.

View full text Add to dashboard Cite

show abstract

“…In order to examine the timing of T. gondii infection, we tested for IgG antibody avidity to T. gondii among all IgM seropositive subjects using the IgG avidity (AVIcomp) test (Abbott Diagnostics, USA). IgG avidity indicates the strength of the binding of IgG antibody to antigen [Delforge et al, ; Rahbari et al, ]. The percent binding increases with the length of time following T. gondii infection.…”

Section: Methodsmentioning

confidence: 99%

Prenatal toxoplasmosis antibody and childhood autism

et al. 2016

View full text Add to dashboard Cite

There is evidence that some maternal infections during the prenatal period are associated with neurodevelopmental disorders, such as childhood autism. However, the association between autism and Toxoplasma gondii (T. gondii), an intracellular parasite, remains unclear. The authors examined whether serologically confirmed maternal antibodies to T. gondii are associated with odds of childhood autism in offspring. The study is based on a nested case-control design of a large national birth cohort (N = 1.2 million) and the national psychiatric registries in Finland. There were 874 cases of childhood autism and controls matched 1:1 on date of birth, sex, birthplace and residence in Finland. Maternal sera were prospectively assayed from a national biobank for T. gondii IgM and IgG antibodies; IgG avidity analyses were also performed. High maternal T. gondii IgM antibody was associated with a significantly decreased odds of childhood autism. Low maternal T. gondii IgG antibody was associated with increased offspring odds of autism. In women with high T. gondii IgM antibodies, the IgG avidity was high for both cases and controls, with the exception of three controls. The findings suggest that the relationship between maternal T. gondii antibodies and odds of childhood autism may be related to the immune response to this pathogen or the overall activation of the immune system. Autism Res 2017, 10: 769-777. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

show abstract

“…After one‐hour incubation, one set of samples was incubated with wash buffer and another with 4M urea (Sigma‐Aldrich, St. Louis, MO, USA) for 5 min and washed twice with wash buffer, and the ELISA protocol was completed as described. The avidity index (AI) was calculated as previously described for the lowest dilution (1:2500) as AI = (U+/U‐) ×100, where ‘U+’ is the OD 490 for wells washed with urea and ‘U‐‘ is the OD 490 for wells washed with PBST.…”

Section: Methodsmentioning

confidence: 99%

Recombinant influenza H7 hemagglutinins induce lower neutralizing antibody titers in mice than do seasonal hemagglutinins

Blanchfield

Kamal

Tzeng

et al. 2014

Influenza Resp Viruses

View full text Add to dashboard Cite

BackgroundVaccines against avian influenza viruses often require high hemagglutinin (HA) doses or adjuvants to achieve serological titers associated with protection against disease. In particular, viruses of the H7 subtype frequently do not induce strong antibody responses following immunization.ObjectivesTo evaluate whether poor immunogenicity of H7 viruses is an intrinsic property of the H7 hemagglutinin.MethodsWe compared the immunogenicity, in naïve mice, of purified recombinant HA from two H7 viruses [A/Netherlands/219/2003(H7N7) and A/New York/107/2003(H7N2)] to that of HA from human pandemic [A/California/07/2009(H1N1pdm09)] and seasonal [A/Perth16/2009(H3N2)] viruses.ResultsAfter two intramuscular injections with purified hemagglutinin, mice produced antibodies to all HAs, but the response to the human virus HAs was greater than to H7 HAs. The difference was relatively minor when measured by ELISA, greater when measured by hemagglutination inhibition assays, and more marked still by microneutralization assays. H7 HAs induced little or no neutralizing antibody response in mice at either dose tested. Antibodies induced by H7 were of significantly lower avidity than for H3 or H1N1pdm09.ConclusionsWe conclude that H7 HAs may be intrinsically less immunogenic than HA from seasonal human influenza viruses.

show abstract

IgG Avidity ELISA Test for Diagnosis of Acute Toxoplasmosis in Humans

Cited by 38 publications

References 17 publications

Determination of IgG avidity in BALB/c mice experimentally infected with Toxocara canis

Determination of IgG avidity in BALB/c mice experimentally infected with Toxocara canis

Prenatal toxoplasmosis antibody and childhood autism

Recombinant influenza H7 hemagglutinins induce lower neutralizing antibody titers in mice than do seasonal hemagglutinins

Contact Info

Product

Resources

About