TY - JOUR
T1 - Selective accumulation of mature asexual stages of Plasmodium falciparum-infected erythrocytes in the placenta
AU - Beeson, James G.
AU - Amin, Nishal
AU - Kanjala, Maxwell
AU - Rogerson, Stephen J.
PY - 2002/10/1
Y1 - 2002/10/1
N2 - A feature of malaria in pregnancy is accumulation of P. falciparum-infected erythrocytes (IEs) in the placenta, which is associated with adverse outcomes for mothers and infants. Infection appears to involve parasite adhesion to molecules such as chondroitin sulfate A, hyaluronic acid, and immunoglobulins. In vitro, adhesion is predominantly a property of mature asexual forms of IEs; however, adhesion of immature or ring forms has recently been reported. We have assessed the parasitemia and developmental stages of IEs in the placenta by examination of placental blood and histological sections with comparison to parasites in the peripheral blood from the same individuals. Approximately 90% of IEs in the placenta were mature forms. Compared to peripheral blood, the placental parasitemia was 10-fold higher and the density of mature IEs was over 200-fold higher. By contrast, the average peripheral and placental ring-stage parasitemias were not significantly different. In 2 of 14 cases, the density of ring forms was higher in placental than in peripheral blood. These findings demonstrate prominent selective accumulation of mature asexual-stage IEs but infrequent accumulation of ring stages in the placental blood spaces, consistent with an important role for mature-stage IE adhesion.
AB - A feature of malaria in pregnancy is accumulation of P. falciparum-infected erythrocytes (IEs) in the placenta, which is associated with adverse outcomes for mothers and infants. Infection appears to involve parasite adhesion to molecules such as chondroitin sulfate A, hyaluronic acid, and immunoglobulins. In vitro, adhesion is predominantly a property of mature asexual forms of IEs; however, adhesion of immature or ring forms has recently been reported. We have assessed the parasitemia and developmental stages of IEs in the placenta by examination of placental blood and histological sections with comparison to parasites in the peripheral blood from the same individuals. Approximately 90% of IEs in the placenta were mature forms. Compared to peripheral blood, the placental parasitemia was 10-fold higher and the density of mature IEs was over 200-fold higher. By contrast, the average peripheral and placental ring-stage parasitemias were not significantly different. In 2 of 14 cases, the density of ring forms was higher in placental than in peripheral blood. These findings demonstrate prominent selective accumulation of mature asexual-stage IEs but infrequent accumulation of ring stages in the placental blood spaces, consistent with an important role for mature-stage IE adhesion.
UR - http://www.scopus.com/inward/record.url?scp=0036784691&partnerID=8YFLogxK
U2 - 10.1128/IAI.70.10.5412-5415.2002
DO - 10.1128/IAI.70.10.5412-5415.2002
M3 - Article
C2 - 12228265
AN - SCOPUS:0036784691
SN - 0019-9567
VL - 70
SP - 5412
EP - 5415
JO - Infection and Immunity
JF - Infection and Immunity
IS - 10
ER -