VAR2CSA and protective immunity against pregnancy-associated Plasmodium falciparum malaria

TY - JOUR

T1 - VAR2CSA and protective immunity against pregnancy-associated Plasmodium falciparum malaria

AU - Hviid, L

AU - Salanti, A

N1 - Keywords: Animals; Antigens, Protozoan; Female; Humans; Malaria, Falciparum; Plasmodium falciparum; Pregnancy; Pregnancy Complications, Parasitic

PY - 2007

Y1 - 2007

N2 - People living in areas with stable transmission of P. falciparum parasites acquire protective immunity to malaria over a number of years and following multiple disease episodes. Immunity acquired this way is mediated by IgG with specificity for parasite-encoded, clonally variant surface antigens (VSA) on the surface of infected erythrocytes (IEs). However, women in endemic areas become susceptible to P. falciparum infection when they become pregnant, particularly for the first time, regardless of previously acquired protective immunity. This conundrum was resolved when it was observed that the selective placental accumulation of IEs that characterizes pregnancy-associated malaria (PAM) is caused by an immunologically and functionally unique subset of VSA (VSAPAM) that is only expressed by parasites infecting pregnant women, and that protective immunity to PAM is mediated by IgG with specificity for VSAPAM. In this review we summarize the research leading to the identification of the distinctly structured PfEMP1 variant VAR2CSA as the dominant PAM-type VSA and as the clinically most important target of the protective immune response to placental P. falciparum infection.

AB - People living in areas with stable transmission of P. falciparum parasites acquire protective immunity to malaria over a number of years and following multiple disease episodes. Immunity acquired this way is mediated by IgG with specificity for parasite-encoded, clonally variant surface antigens (VSA) on the surface of infected erythrocytes (IEs). However, women in endemic areas become susceptible to P. falciparum infection when they become pregnant, particularly for the first time, regardless of previously acquired protective immunity. This conundrum was resolved when it was observed that the selective placental accumulation of IEs that characterizes pregnancy-associated malaria (PAM) is caused by an immunologically and functionally unique subset of VSA (VSAPAM) that is only expressed by parasites infecting pregnant women, and that protective immunity to PAM is mediated by IgG with specificity for VSAPAM. In this review we summarize the research leading to the identification of the distinctly structured PfEMP1 variant VAR2CSA as the dominant PAM-type VSA and as the clinically most important target of the protective immune response to placental P. falciparum infection.

U2 - 10.1017/S0031182007000121

DO - 10.1017/S0031182007000121

M3 - Journal article

C2 - 17958922

SN - 0031-1820

VL - 134

SP - 1871

EP - 1876

JO - Parasitology

JF - Parasitology

IS - Pt 13

ER -