DENV NS1 refolded at HHP is antigenic.

A) Titers of NS1-specific IgG measured by ELISA using NS1 refolded with HHP at pH 10.5 in different conditions. The ELISA was employing with a control sera obtained from patients that had been previously infected with DENV (gray bars) or not (white bars). B) Evaluation of the preservation of conformational epitopes in NS1. NS1 obtained at HHP, pH 10.5 + Arg + GSH/GSSG was previously denatured (100 °C, 10 min) or not and analyzed by ELISA for reactivity with a serum from a patient previously infected with DENV. For A and B, the IB compression was performed in 2.4 kbar / 0.4 kbar. C) Titers of NS1 refolded at HHP at pH 10.5 + Arg + GSH/GSSG by incubation at 2.4 kbar (90 min.) and 0.4 kbar for the time indicated in the figure. Values are expressed as mean ± SD of the data. All NS1 samples had low reactivity with control serum in ELISA. Control NS1, obtained from the same clone used in this study and refolded using traditional protocols performed at atmospheric pressure. * p < 0.05, ** p <0.01, *** p<0.001 (Two way ANOVA with Bonferroni post-test). The results shown are the representative of 3 independent assays.