Fig 1.
Screening of reactive peptides using monoclonal antibodies.
(A) Heatmap matrix of peptides assessed with monoclonal specific antibodies against ZIKV or DENV in an indirect IgG ELISA platform. Highest scores were selected for soluble synthesis. Peptide ZV-53 was not stable in soluble form and excluded from analysis. (B) IgG pepELISA for validation of soluble peptides. Serum samples from patients validated with PRNT were evaluated on plates with DV-15, DV-20, ZV-54, and ZV-107.
Fig 2.
PepELISA and standard ELISA using validated samples.
A total of 170 serum samples validated with PRNT were tested on plates with: (A) DV-15; (B) DV-20; and (C) ZV-54. Peptide ZV-107 did not recognize any of the serum samples and was excluded from the further analysis. The same panel of samples were also tested with: (D) a mix of the NS1 protein of DENV-1, DENV-2, DENV-3, and DENV-4; and (E) To complete the positive controls, we tested the samples in plates coated with ZIKV NS1 protein. Gray area indicates the cutoff values based on the ROC curve specific for each antigen (Fig 3). Diagnostic performance analysis and cutoff values are presented in Table 1. Samples within the gray area are considered negative.
Table 1.
Measure of diagnostic performance for DENV NS1 protein, ZIKV NS1 protein, and for peptides DV-15, DV-20, and ZV-54.
Fig 3.
Performance of the pepELISA and standard NS1 ELISA using validated samples.
Receiver Operating Characteristic (ROC) curves of pepELISA for the peptides: (A) DV-15; (B) DV-20; (C) ZV-54; and standard ELISA against DENV NS1 mix (D), and ZIKV NS1 (E). Performance is demonstrated in True Positive Rate (Sensitivity %) versus False Positive Rate (100%—Specificity %).
Fig 4.
Samples selection and case distribution according to serological sub cohort.
Criteria for inclusion into the cohort included laboratory-confirmed infection by RT-PCR and/or NS-1 ELISA or immunochromatographic method.
Table 2.
Demographic characteristics, frequency of signs and symptoms compatible with dengue and laboratory findings of 879 patients of sub cohorts.
Table 3.
Frequency of warning and severity signs of dengue and clinical outcome of 879 patients of sub cohorts.
Table 4.
Risk to development of severe forms and hospitalization in dengue.
Fig 5.
Expression of cytokines according to serological sub cohorts.
* p < 0.05; ** p< 0.01.
Fig 6.
Inflammatory response models in acute dengue infection in primary and secondary dengue infection [left and middle panel] and proposed mechanism of response after previous Zika infection [right panel]. Created with BioRender.com.