Dynamics of anti-VAR2CSA immunoglobulin G response in a cohort of senegalese pregnant women.
BACKGROUND
Pregnancy-associated malaria (PAM) is precipitated by the accumulation of parasites in the placental intervillous spaces and causes maternal anemia and low birth weight. In PAM, placental parasites adhere to chondroitin sulfate A (CSA) through a unique set of variant surface antigens (VSAPAM). Several studies have shown that 1 var gene, var2csa, is transcribed at high levels and expressed in CSA-binding Plasmodium falciparum parasites.


METHODS
Plasma levels of anti-VAR2CSA immunoglobulin G (IgG) in Senegalese women were measured during pregnancy by enzyme-linked immunosorbent assay, using 3 recombinant proteins representing 3 domains of the var2csa gene product.


RESULTS
The 3 recombinant proteins were specifically recognized by plasma from pregnant women but not by control plasma. A parity-dependent recognition pattern was observed with 2 of the 3 VAR2CSA antigens. A kinetic study demonstrated that a single P. falciparum infection was able to trigger a VAR2CSA-specific antibody response. Among women with infected placentas, women with high anti-VAR2CSA IgG levels at enrollment were more likely to present with a past infection than with an acute/chronic infection.


CONCLUSIONS
Anti-VAR2CSA IgGs are involved in clinical protection against pregnancy-associated malaria and strengthens the hope for making a VAR2CSA-based vaccine.
Tuikue Ndam
N G
NG
Institut de Recherche pour le Développement, UR010, Mother and Child Health in the Tropics, Universite Paris Descartes, Paris, France, and Thiadiaye Hospital, Senegal.
Salanti
A
A
Le-Hesran
J-Y
JY
Cottrell
G
G
Fievet
N
N
Turner
L
L
Sow
S
S
Dangou
J-M
JM
Theander
T
T
Deloron
P
P
D000293:Adolescent; D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000737:chemistry / Q000276:immunology*; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D016778:Malaria, Falciparum / Q000276:immunology*; D010920:Placenta / Q000469:parasitology; D010963:Plasmodium falciparum / Q000276:immunology* / Q000378:metabolism; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000276:immunology*; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins; D012675:Senegal
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D011508:Chondroitin Sulfate Proteoglycans; D007074:Immunoglobulin G; D011994:Recombinant Proteins