Development of a Multiplex Bead Assay for the Detection of IgG Antibody Responses to Guinea Worm

Am J Trop Med Hyg. 2020 Dec;103(6):2294-2304. doi: 10.4269/ajtmh.20-0511. Epub 2020 Sep 3.


The success of the Guinea Worm (GW) Eradication Program over the past three decades has been tempered by the persistence of GW disease in a few African nations and the potential for a future resurgence in cases. Domestic dogs are now a major concern as a disease reservoir as large numbers of cases of canine GW disease are now reported each year, mainly along the Chari River in Chad. As a first step toward the development of a serologic assay for dogs, archived human plasma samples from dracunculiasis-positive donors from Togo were used to select adult female GW antigens for peptide sequencing and cloning. Eight protein sequences of interest were expressed as recombinant glutathione-S-transferase (GST) fusion proteins, and the most promising proteins were coupled to carboxylated microspheres for use in multiplex assays. A thioredoxin-like protein (TRXL1) and a domain of unknown function (DUF148) were assessed for total IgG and IgG4 reactivities using a panel of specimens from GW cases, uninfected donors, and individuals infected with various nematode worms, including Onchocerca volvulus. Both the DUF148-GST and the TRXL1-GST assays cross-reacted with O. volvulus sera, but the latter assay was always the more specific. The IgG4 and total IgG TRXL1-GST assays both had sensitivities > 87% and specificities > 90%. Maximum specificity (> 96%) was obtained with the total IgG assay when reactivity to both antigens was used to define a positive case. Given the good performance of the human assay, we are now working to modify the assay for dog assessments.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antibodies, Helminth / immunology*
  • Antigens, Helminth / genetics
  • Antigens, Helminth / immunology*
  • Blotting, Western
  • Cross Reactions
  • Disease Eradication
  • Disease Reservoirs / parasitology
  • Dog Diseases / diagnosis
  • Dog Diseases / immunology
  • Dogs
  • Dracunculiasis / diagnosis*
  • Dracunculiasis / immunology
  • Dracunculiasis / prevention & control
  • Dracunculiasis / veterinary*
  • Dracunculus Nematode
  • Electrophoresis, Polyacrylamide Gel
  • Glutathione Transferase / genetics
  • Humans
  • Immunoglobulin G / immunology*
  • Onchocerca volvulus
  • Onchocerciasis / diagnosis
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Sensitivity and Specificity
  • Serologic Tests
  • Thioredoxins / genetics


  • Antibodies, Helminth
  • Antigens, Helminth
  • Immunoglobulin G
  • Recombinant Fusion Proteins
  • Thioredoxins
  • Glutathione Transferase