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. 2019 Aug 2;14(8):e0215708.
doi: 10.1371/journal.pone.0215708. eCollection 2019.

Modulated Zika virus NS1 conjugate offers advantages for accurate detection of Zika virus specific antibody in double antigen binding and Ig capture enzyme immunoassays

Affiliations

Modulated Zika virus NS1 conjugate offers advantages for accurate detection of Zika virus specific antibody in double antigen binding and Ig capture enzyme immunoassays

Richard S Tedder et al. PLoS One. .

Abstract

The accurate diagnosis and seroprevalence investigations of Zika virus (ZKV) infections remain complex due to cross reactivity with other flaviviruses. Two assay formats, both using labelled Zika virus NS1 antigen as a revealing agent (a double antigen binding assay, DABA, and an immunoglobulin Ig capture assay, G capture) were initially developed and compared with the indirect EuroimmunZ assay for the detection of anti-Zika antibody. Of 147 pre-Zika period serum samples, 39 (27%) were reactive in the EuroimmunZ or the DABA assays, 28 sera concordantly so. Such false reactivity was influenced by the serotype of Dengue virus (DV) to which individuals had been exposed to. Thus, of sera from patients undergoing secondary Dengue virus infection of known serotype, 91%, 45% and 28% of Dengue virus serotype 2, 3 and 4 respectively were reactive in one or more of the three assays. A novel method of quenching false sero-reactivity was therefore developed for the DABA and G capture assays. Initial addition of a single homologous Dengue virus serotype 3 NS1Ag quench significantly ablated false reactivities in the pre-Zika period sera. An equipotent quadrivalent quench comprising homologous Dengue virus serotypes 1 to 4 NS1Ag was shown to be optimum yet retained sensitivity for the detection of specific anti-Zika antibody. Comparing DABA and G capture assays using quenched and unquenched conjugates in comparison with EuroimmunZ early in the course of PCR-confirmed infection indicated that a significant component of the apparent early anti-ZIKA antibody response is likely to be due to a Zika virus-driven anamnestic anti-Dengue virus response. The increased specificity provided by homologous antigen quenching is likely to provide a significant improvement in sero-diagnostics and to be of clinical value.

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Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Illustration detailing the immunoglobulin G capture assay (G capture) and the double antigen binding assay (DABA).
The G Capture solid phase (cross hatched) is coated with rabbit anti-human gamma FC to capture G from the clinical sample in the first step of the assay. After washing, conjugate is applied and specific antibody (Y) revealed by ZIKA virus NS1 antigen (ZKVNS1Ag) labelled with horseradish peroxidase (HRPO; Z *, standard). The DABA solid-phase is coated with ZKVNS1Ag to capture antibody to NS1Ag of any class. After washing, conjugate is applied and bound antibody (Y) revealed by ZKV NS1Ag labelled with HRPO as above.
Fig 2
Fig 2. EuroimmunZ vs Unquenched DABA reactivity in pre-Zika era panels.
Plot of sample to cut off (S/CO) ratios of 147 pre-Zika era samples tested in un-quenched DABA and EuroimmunZ. Fourteen samples with EuroimmunZ ratios <1.1 were considered indeterminate by EuroimmunZ criteria. Three samples were reactive by DABA alone. Solid lines represent the cut off value for each assay. Trend line is displayed.
Fig 3
Fig 3. Antibody reactivity across three assays in samples from PCR confirmed Zika cases.
Venn plots for 91 samples from patients with PCR confirmed ZKV infection. Samples giving sample to cut off ratios>1.0 were defined as reactive. The right hand plot shows reactivity for the panel of 91 samples tested in the three different assays. The three panels on the left in vertical order show the reactivity broken down into the first week, second to fourth week and one or more year after onset of symptoms. The individual reactivity of samples in each test is shown and the overall reactivity for each assay displayed.
Fig 4
Fig 4
4A and 4B. G capture and DABA data on Zika confirmed panels comparing DV3NS1Ag quenched and un-quenched conjugates. X by Y plots of sample reactivity from patients known to have been infected with ZKV. Reactivity is expressed as sample to cut off ratios when tested using un-quenched conjugate and rDV3NS1Ag-quenched conjugate. Left hand panel (A) displays the results with 59 ZKV convalescent sera (São Paulo and Rio de Janeiro) tested in the DABA using either unquenched or quenched conjugates. Dotted line is a line of interpolated equivalence assuming no difference in reactivity. Solid lines represent the assay cut off values. Right hand panel (B) similarly displays the reactivity of 41 samples from patients with confirmed ZKV infection tested in the G capture using unquenched and quenched conjugate diluents. Samples from patients with proven ZKV showing a reduced reactivity resulting from the quenched conjugate are circled in both panels.
Fig 5
Fig 5
5A and 5B. Antibody reactivity in Dengue quadrivalent antigen quenched assay: comparison with unquenched DABA and EuroimmunZ. X by Y plots of reactivity displayed by 87 selected samples (São Paulo and Rio de Janeiro) drawn from the pre ZIKA-era panel expressed as sample to cut off ratios. Left hand panel (A) displays the results with sera tested in DABA using both quad quenched and unquenched conjugates. Right hand panel (B) similarly displays the reactivity of the same samples tested in quad quenched DABA and EuroimmunZ.
Fig 6
Fig 6. Zika seroconversion panels: EuroimmunZ vs Quadrivalent antigen quenched G capture by time from infection.
X by Y plots of sample reactivity, expressed as sample to cut off ratios in G capture assay using quad quenched conjugate and in EuroimmunZ, of 38 samples grouped by time since onset of symptoms.

References

    1. Dick GW, Kitchen SF, Hadow AJ. ZKV virus. I. Isolations and serological specificity. Trans R Soc Trop Med Hyg. 1952; 46(5): 509–20. 10.1016/0035-9203(52)90042-4 - DOI - PubMed
    1. Kindhauser MK, Allen T, Frank V, Santhana RS and Dye C. Zika the origin and spread of a mosquito-borne virus. Bull World Health Organ. 2016; 94(9): 675–686C. 10.2471/BLT.16.171082 - DOI - PMC - PubMed
    1. Moore DL, Causey OR, Carey DE, Reddy S, Cooke AR, Akinkugbe FM et al. Arthropod-borne viral infections of man in Nigeria, 1964–1970. Ann Trop Med Pasrasitol. 1975; 69(1): 49–64. - PubMed
    1. Musso D, Richard V, Teissier A, Stone M, Lanteri MC, Latoni G, et al. Detection of Zika virus RNA in semen of asymptomatic blood donors. Clin Microbiol Infect. 2017; 23(12): 1001.e1–1001.e3 - PMC - PubMed
    1. Barjas-Castro ML, Angerami RN, Cunha MS, Suzuki A, Nogueira JS Rocco IM, et al. Probable transfusion-transmitted Zika virus in Brazil. Transfusion 2016; 56(7): 1684–1688. 10.1111/trf.13681 - DOI - PubMed

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