TY - JOUR
T1 - Identification and characterization of Loa loa antigens responsible for cross-reactivity with rapid diagnostic tests for lymphatic filariasis
AU - Hertz, Marla I.
AU - Nana-Djeunga, Hugues
AU - Kamgno, Joseph
AU - Jelil Njouendou, Abdel
AU - Chawa Chunda, Valerine
AU - Wanji, Samuel
AU - Rush, Amy
AU - Fischer, Peter U.
AU - Weil, Gary J.
AU - Budge, Philip J.
N1 - Funding Information:
workwassupportedbyNationalInstitutefor AllergyandInfectiousDisease(NIAID)grant K08AI121422(PJB),andbyfundsfrom WashingtonUniversityinSt.Louis(collectionof Akonolinga/Awaesamples)andanNIHLoan RepaymentPrograms(NIAID)award.Further supportwasprovidedbytheCoalitionfor OperationalResearchonNeglectedTropical Diseases(COR-NTD,http://www.ntdsupport.org/
Funding Information:
This study made use of the National Institute of Health/National Institute of General Medical Sciences (NIH / NIGMS) Biomedical Mass Spectrometry Resource at Washington University in St. Louis, MO, which is supported by National Institutes of Health / National Institute of General Medical Sciences Grant # 8P41GM103422. This work was supported by National Institute for Allergy and Infectious Disease (NIAID) grant K08AI121422 (PJB), and by funds from Washington University in St. Louis (collection of Akonolinga/Awae samples) and an NIH Loan Repayment Programs (NIAID) award. Further support was provided by the Coalition for Operational Research on Neglected Tropical Diseases (COR-NTD, http://www.ntdsupport.org/cor-ntd, collection of East Region samples, awarded to SW and PUF) and the Bill and Melinda Gates Foundation (https://www.gatesfoundation.org/, grant OPPGH 5342 awarded to PUF and GW). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. We would like to thank the members of the Weil, Townsend and Mitreva labs for advice and thoughtful discussion. This study made use of the NIH / NIGMS Biomedical Mass Spectrometry Resource at Washington University in St. Louis, MO.
Publisher Copyright:
© 2018 Hertz et al. http://creativecommons.org/licenses/by/4.0/.
PY - 2018/11
Y1 - 2018/11
N2 - The Global Program to Eliminate Lymphatic Filariasis (LF) relies on rapid diagnostic tests (RDTs) to determine where annual mass drug administration for LF is required and when it can be stopped. These tests detect a Wuchereria bancrofti glycoprotein in the blood of infected persons via a carbohydrate moiety recognized by the monoclonal antibodies AD12 and DH6.5. Loiasis cross-reactivity with LF RDTs has recently been recognized as a serious obstacle to LF elimination in loiasis-endemic areas. To better understand the nature of this cross-reactivity, we used the DH6.5 antibody to immunoaffinity purify Loa loa antigens from the sera of individuals with a positive RDT due to loiasis. Immunoblot analysis revealed many circulating AD12/DH6.5-reactive antigens, and proteomic analysis identified multiple L. loa proteins in LF RDT-positive loiasis sera. These included both secreted and somatic proteins, suggesting that they may be released by dying L. loa adult worms and/or microfilariae. Unlike the single high molecular weight W. bancrofti circulating filarial antigen that is reliably present in the blood of persons with bancroftian filariasis, reactive L. loa antigens appeared to be only transiently present in the blood of a subset of persons with loiasis. These key differences between the circulating antigens of W. bancrofti and L. loa can be used to differentiate positive results generated by both species and may lead to improved diagnostic tests for LF and loiasis.
AB - The Global Program to Eliminate Lymphatic Filariasis (LF) relies on rapid diagnostic tests (RDTs) to determine where annual mass drug administration for LF is required and when it can be stopped. These tests detect a Wuchereria bancrofti glycoprotein in the blood of infected persons via a carbohydrate moiety recognized by the monoclonal antibodies AD12 and DH6.5. Loiasis cross-reactivity with LF RDTs has recently been recognized as a serious obstacle to LF elimination in loiasis-endemic areas. To better understand the nature of this cross-reactivity, we used the DH6.5 antibody to immunoaffinity purify Loa loa antigens from the sera of individuals with a positive RDT due to loiasis. Immunoblot analysis revealed many circulating AD12/DH6.5-reactive antigens, and proteomic analysis identified multiple L. loa proteins in LF RDT-positive loiasis sera. These included both secreted and somatic proteins, suggesting that they may be released by dying L. loa adult worms and/or microfilariae. Unlike the single high molecular weight W. bancrofti circulating filarial antigen that is reliably present in the blood of persons with bancroftian filariasis, reactive L. loa antigens appeared to be only transiently present in the blood of a subset of persons with loiasis. These key differences between the circulating antigens of W. bancrofti and L. loa can be used to differentiate positive results generated by both species and may lead to improved diagnostic tests for LF and loiasis.
UR - http://www.scopus.com/inward/record.url?scp=85058126391&partnerID=8YFLogxK
U2 - 10.1371/journal.pntd.0006963
DO - 10.1371/journal.pntd.0006963
M3 - Article
C2 - 30444866
AN - SCOPUS:85058126391
VL - 12
JO - PLoS Neglected Tropical Diseases
JF - PLoS Neglected Tropical Diseases
SN - 1935-2727
IS - 11
M1 - e0006963
ER -