In vivo switching between variant surface antigens in human Plasmodium falciparum infection

TY - JOUR

T1 - In vivo switching between variant surface antigens in human Plasmodium falciparum infection

AU - Staalsoe, Trine

AU - Hamad, Amel A

AU - Hviid, Lars

AU - Elhassan, Ibrahim M

AU - Arnot, David E

AU - Theander, Thor G

N1 - Keywords: Animals; Antibodies, Protozoan; Antigenic Variation; Antigens, Protozoan; Cohort Studies; DNA, Protozoan; Erythrocytes; Flow Cytometry; Humans; Malaria, Falciparum; Plasmodium falciparum; Polymerase Chain Reaction; Retrospective Studies; Sudan

PY - 2002

Y1 - 2002

N2 - A semi-immune individual was retrospectively found to have maintained an apparently monoclonal and genotypically stable asymptomatic infection for months after clinical cure of a Plasmodium falciparum malaria episode. Before the attack, the individual had no antibodies to variant surface antigens (VSAs) expressed by an isolate (isolate A) obtained at the time of the episode or by a genotypically identical isolate (isolate B) obtained from the same individual 3 months later. Six weeks after the attack, a strong isolate A-specific VSA antibody response had developed in the complete absence of isolate B-specific antibodies. In contrast, plasma obtained 7 months after the attack contained high levels of VSA antibodies recognizing both isolates. This is the first direct evidence of in vivo switching between VSAs in human P. falciparum infection. Our results suggest that VSA switching is an important survival strategy of P. falciparum, enabling the parasite to persist despite protective, parasite-specific immune responses.

AB - A semi-immune individual was retrospectively found to have maintained an apparently monoclonal and genotypically stable asymptomatic infection for months after clinical cure of a Plasmodium falciparum malaria episode. Before the attack, the individual had no antibodies to variant surface antigens (VSAs) expressed by an isolate (isolate A) obtained at the time of the episode or by a genotypically identical isolate (isolate B) obtained from the same individual 3 months later. Six weeks after the attack, a strong isolate A-specific VSA antibody response had developed in the complete absence of isolate B-specific antibodies. In contrast, plasma obtained 7 months after the attack contained high levels of VSA antibodies recognizing both isolates. This is the first direct evidence of in vivo switching between VSAs in human P. falciparum infection. Our results suggest that VSA switching is an important survival strategy of P. falciparum, enabling the parasite to persist despite protective, parasite-specific immune responses.

U2 - 10.1086/342390

DO - 10.1086/342390

M3 - Journal article

C2 - 12195363

SN - 0022-1899

VL - 186

SP - 719

EP - 722

JO - Journal of Infectious Diseases

JF - Journal of Infectious Diseases

IS - 5

ER -