5 research outputs found
A human inferred germline antibody binds to an immunodominant epitope and neutralizes Zika virus
<div><p>The isolation of neutralizing monoclonal antibodies (nmAbs) against the Zika virus (ZIKV) might lead to novel preventative strategies for infections in at-risk individuals, primarily pregnant women. Here we describe the characterization of human mAbs from the plasmablasts of an acutely infected patient. One of the 18 mAbs had the unusual feature of binding to and neutralizing ZIKV despite not appearing to have been diversified by affinity maturation. This mAb neutralized ZIKV (Neut<sub>50</sub> ~ 2 μg/ml) but did not react with any of the four dengue virus serotypes. Except for the expected junctional diversity created by the joining of the V-(D)-J genes, there was no deviation from immunoglobulin germline genes. This is a rare example of a human mAb with neutralizing activity in the absence of detectable somatic hypermutation. Importantly, binding of this mAb to ZIKV was specifically inhibited by human plasma from ZIKV-exposed individuals, suggesting that it may be of value in a diagnostic setting.</p></div
P1F12 mAb binds to whole ZIKV, but not to DENV or recombinant ZIKV E protein.
<p>P1F12 binding determined by both Virus Capture ELISA (top panel) and recombinant E protein ELISA (bottom panel) (19kDa protein without hydrophobic region). Control Absorbances: Whole Virus—Hu0004 (ZIKV+): 2.017, Hu002 (ZIKV-): 0.046. Control Absorbances rE: Whole Virus—Hu0004 (ZIKV+): 2.006, Hu002 (ZIKV-): 0.033.</p
P1F12 mAb binds to whole ZIKV, but not DENV.
<p>The extent of mAb binding to ZIKV and the four DENV serotypes was quantified using a virus capture ELISA. The ability of purified mAbs (1 μg / ml) to bind to captured DENV and ZIKV was assessed. Absorbance (Abs 450) values higher than three times the negative control wells were considered binders.</p
Inhibition of ZIKV-P1F12 binding discriminates plasma from ZIKV and DENV exposures.
<p>A modified virus capture ELISA was conducted to assess the ability of plasma from 46 individuals to block the binding of P1F12 to whole ZIKV. Captured ZIKV was incubated with 1/10 diluted plasma from naïve (US and Brazil) and DENV+, YFV+ or ZIKV+ volunteers prior to addition of purified P1F12. Viral infection was determined by RT-PCR. ZIKV-bound P1F12 was detected using an HRP-conjugated secondary Ab specific for the rhesus IgG1 Fc region of recombinant P1F12. ZIKV+ (blue circles), but not ZIKV- (gray circles) plasma inhibited binding of P1F12 mAb to ZIKV.</p