TY - JOUR
T1 - Antibodies to PfsEGXP, an early gametocyte-enriched phosphoprotein, predict decreased plasmodium falciparum gametocyte density in humans
AU - Nixon, Christian P.
AU - Nixon, Christina E.
AU - Michelow, Ian C.
AU - Silva-Viera, Rayna A.
AU - Colantuono, Bonnie
AU - Obeidallah, Aisha S.
AU - Jha, Ambrish
AU - Dockery, Dominique
AU - Raj, Dipak
AU - Park, Sangshin
AU - Duffy, Patrick E.
AU - Kurtis, Jonathan D.
N1 - Publisher Copyright:
© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved.
PY - 2018/10/20
Y1 - 2018/10/20
N2 - Background. Antigametocyte-specific immune responses may regulate Plasmodium falciparum gametocyte density, providing the rationale for pursuing transmission-blocking vaccines (TBVs) that target gametocytes in the human host. Methods. To identify novel antigametocyte TBV antigens, we interrogated the gametocyte proteome with our whole proteome differential screening method using plasma from a treatment-reinfection study conducted in western Kenya. At the start of the high-transmission season, 144 males (12-35 years) were enrolled and treated with quinine and doxycycline, peripheral venous blood samples were obtained, volunteers were observed, and weekly blood films were obtained for 18 weeks to quantify gametocytemia. Using plasma pooled from individuals with low versus high gametocyte carriage, we differentially screened a P falciparum gametocyte stage complementary deoxyribonucleic acid expression library. Results. We identified 8 parasite genes uniquely recognized by gametocyte-resistant but not by gametocyte-susceptible individuals. Antibodies to one of these antigens, PfsEGXP, predicted lower gametocytemia measured over the 18-week transmission season (P = .021). When analyzed dichotomously, anti-PfsEGXP responders had 31% lower gametocyte density over 18 weeks of follow-up, compared with nonresponders (P = .04). Conclusions. PfsEGXP is one of the first reported gametocyte-specific target of antibodies that predict decreased gametocyte density in humans and supports our novel TBV antigen discovery platform.
AB - Background. Antigametocyte-specific immune responses may regulate Plasmodium falciparum gametocyte density, providing the rationale for pursuing transmission-blocking vaccines (TBVs) that target gametocytes in the human host. Methods. To identify novel antigametocyte TBV antigens, we interrogated the gametocyte proteome with our whole proteome differential screening method using plasma from a treatment-reinfection study conducted in western Kenya. At the start of the high-transmission season, 144 males (12-35 years) were enrolled and treated with quinine and doxycycline, peripheral venous blood samples were obtained, volunteers were observed, and weekly blood films were obtained for 18 weeks to quantify gametocytemia. Using plasma pooled from individuals with low versus high gametocyte carriage, we differentially screened a P falciparum gametocyte stage complementary deoxyribonucleic acid expression library. Results. We identified 8 parasite genes uniquely recognized by gametocyte-resistant but not by gametocyte-susceptible individuals. Antibodies to one of these antigens, PfsEGXP, predicted lower gametocytemia measured over the 18-week transmission season (P = .021). When analyzed dichotomously, anti-PfsEGXP responders had 31% lower gametocyte density over 18 weeks of follow-up, compared with nonresponders (P = .04). Conclusions. PfsEGXP is one of the first reported gametocyte-specific target of antibodies that predict decreased gametocyte density in humans and supports our novel TBV antigen discovery platform.
KW - Gametocytes
KW - Naturally acquired immunity
KW - Plasmodium falciparum
UR - http://www.scopus.com/inward/record.url?scp=85055201381&partnerID=8YFLogxK
U2 - 10.1093/infdis/jiy416
DO - 10.1093/infdis/jiy416
M3 - Article
C2 - 29982707
AN - SCOPUS:85055201381
SN - 0022-1899
VL - 218
SP - 1792
EP - 1801
JO - Journal of Infectious Diseases
JF - Journal of Infectious Diseases
IS - 11
ER -