Additional file 1: Figure S1. of An isothermal DNA amplification method for detection of Onchocerca volvulus infection in skin biopsies

Cq values of actb qPCR assay on the 150 gDNA samples. Mean and standard deviation are indicated, as well as the line indicating mean + 2 standard deviations. The four samples that had Cq values above this cut-off were excluded in further analyses. (PDF 29 kb

Additional file 2: Figure S2. of An isothermal DNA amplification method for detection of Onchocerca volvulus infection in skin biopsies

Calibration curve of the O-150 qPCR assay. Calibration samples have been analyzed in 4-fold. Geometric mean and 95% confidence interval are indicated. (PDF 34 kb

Additional file 1: of 2-methyl butyramide, a previously identified urine biomarker for Ascaris lumbricoides, is not present in infected Indonesian individuals

1H-NMR Spectrum of 2-methyl butyramide. (PPTX 230 kb

Proof-of-Concept Rapid Diagnostic Test for Onchocerciasis: Exploring Peptide Biomarkers and the Use of Gold Nanoshells as Reporter Nanoparticles

Three <i>O. volvulus</i> immunogenic peptide sequences recently discovered by peptide microarray were adapted to a lateral flow assay (LFA). The LFA employs gold nanoshells as novel high-contrast reporter nanoparticles and detects a serological response against the 3 peptides, found in OvOC9384, OvOC198, and OvOC5528, respectively. When tested on 118 sera from <i>O. volvulus</i> infected patients and 208 control sera, the LFA was 90%, 63%, and 98% sensitive for each peptide, respectively, and 99–100% specific vs samples from healthy volunteers. Samples of other filarial infections cross-reacted by 7–24%. The sensitivity, specificity, and cross-reactivity values matched those obtained by ELISA with the same sample set. While the exact choice of peptide(s) will require fine-tuning, this work establishes that <i>O. volvulus</i> peptides identified by peptide microarray can be translated into an antibody-based LFA and that gold nanoshells provide the same sensitivity, specificity, and cross-reactivity as the corresponding ELISA assays

Summary of the data extrapolated from our measurements.

<p>Summary of the data extrapolated from our measurements.</p

Schematics of the experimental setup (not to scale).

<p>(a) Experiments are conducted in a bio-safety cabinet to keep all aerosolized virus contained. The setup includes a Collison nebulizer to aerosolize using compressed air and viral solutions provided by a syringe pump. Tubing directs the airborne viruses into the sampling unit (b): (1) our ESP sampler or (2) gelatin filters for comparison. A downstream vacuum pump maintains a constant flow and under pressure inside the ESP sampler. (b) Details of the sampling units: (1) Our ESP sampler includes a three-electrode corona discharge electrostatic precipitator to capture the aerosol particle directly into an integrated liquid collector with a miniaturized volume of 150 μL; (2) gelatin filters are used for comparative measurement of the total amount of virus effectively entering the ESP sampler after nebulization. The filters are housed in a specific cassette placed at the aerosol inlet.</p

Measurements of the total amount of viruses detected with qPCR versus the total amount of viruses entering the ESP sampler.

<p>Linear regressions were performed using the least-square method on data groups obtained using EP1 and EP2. The qPCR LoD reported to the sampling volume is plotted with a horizontal dashed red arrow and enables calculating the theoretical system LoDs, indicated with black arrows. The collection efficiencies for EP1 and EP2 are significantly different with a probability P = 0.0158 < 0.05 and are indicated with the corresponding standard error. *For EP3, only a single measurement was successfully obtained. The corresponding collection efficiency can be estimated using <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0174314#pone.0174314.e001" target="_blank">Eq 1</a>.</p

Additional file 1: of Evaluation of the diagnostic potential of urinary N-Acetyltyramine-O,β-glucuronide (NATOG) as diagnostic biomarker for Onchocerca volvulus infection

Overview of data obtained for all samples (urinary NATOG, urinary creatinine and Ov16 status). (XLSX 18 kb

Bioassay Development for Ultrasensitive Detection of Influenza A Nucleoprotein Using Digital ELISA

Flu is caused by the influenza virus that, due to mutations, keeps our body vulnerable for infections, making early diagnosis essential. Although immuno-based diagnostic tests are available, they have low sensitivity and reproducibility. In this paper, the prospect of detecting influenza A virus using digital ELISA has been studied. To appropriately select bioreceptors for this bioassay, seven commercial antibodies against influenza A nucleoprotein were methodically tested for their reactivity and binding affinity. The study has been performed on two markedly different platforms, being an enzyme-linked immunosorbent assay and a surface plasmon resonance system. The selected antibodies displayed completely different behavior on the two platforms and in various assay configurations. Surprisingly, the antibodies that showed overall good reactivity on both platforms had the highest dissociation constant among the tested antibodies, suggesting that, although important, binding affinity is not the only parameter to be considered when selecting antibodies. Moreover, only one antibody had the capacity to capture the nucleoprotein directly in lysis buffer used for releasing this viral protein, which might pose a huge advantage when developing assays with a fast time-to-result. This antibody was implemented on an in-house developed digital ELISA platform for ultrasensitive detection of recombinant nucleoprotein, reaching a detection limit of 4 ± 1 fM in buffer and 10 ± 2 fM in 10-fold diluted nasopharyngeal swabs, which is comparable to currently available fast molecular detection techniques. These results point to a great potential for ultrasensitive immuno-based influenza detection

Hypothetical prevalence curve (dots) for a successful STH elimination program, overlaid with program phase (diamond for transition points) and diagnostic use-cases.

<p>MDA, mass drug administration; STH, soil-transmitted helminth.</p