Tuikue Ndam Nicaise G, Fievet Nadine, Bertin Gwladys, Cottrell Gilles, Gaye Alioune, Deloron Philippe
Institut de Recherche pour le Developpement (IRD), UR010, Mother and Child Health in the Tropics, Faculte de Pharmacie, Paris, France.
J Infect Dis. 2004 Dec 1;190(11):2001-9. doi: 10.1086/425521. Epub 2004 Oct 27.
Pregnancy-associated malaria is characterized by selection and multiplication, in the placenta, of a distinct population of Plasmodium falciparum expressing particular variant surface antigens (VSAs) that adhere to chondroitin sulfate A (CSA).
The adhesion of 40 freshly collected placental parasite isolates to bovine CSA and human placental low-sulfated chondroitin proteoglycans (CSPGs) was investigated. Plasma samples from 30 pregnant women were used to test, by flow cytometry, their recognition of and their adhesion-inhibition capacity toward 6 of these isolates.
Adhesion to CSA and CSPGs varied between isolates but was strongly correlated between receptors (P<.001). Adhesion of isolates to receptors strongly and negatively correlated with low birth weight (LBW) of the neonate (odds ratio [95% confidence interval], 5.2 [1.1-25.1]). In plasma samples from pregnant women, the level of specific immunoglobulin G against each placental isolate (anti-VSA(PAP)) strongly correlated with the level of anti-VSA(PAP) antibodies against all other isolates (P<.05) and increased with parity in all isolates (P<.01). Conversely, adhesion-inhibitory antibodies did not correlate with isolates or with the level of anti-VSA(PAP) antibodies.
The level of adhesion of placental parasites to chondroitin sulfate receptors is an important risk factor for LBW. Parasite heterogeneity suggests that they are composed of mixed adhesion phenotypes capable of inducing immune responses to a range of different and overlapping targets.
妊娠相关疟疾的特征是，在胎盘中，一群表达特定变异表面抗原（VSA）的恶性疟原虫进行选择和增殖，这些抗原可黏附于硫酸软骨素A（CSA）。
研究了40株新鲜采集的胎盘寄生虫分离株对牛CSA和人胎盘低硫酸化硫酸软骨素蛋白聚糖（CSPG）的黏附情况。使用30名孕妇的血浆样本，通过流式细胞术检测她们对其中6株分离株的识别能力及其黏附抑制能力。
各分离株对CSA和CSPG的黏附情况各不相同，但在不同受体之间呈强相关性（P<0.001）。分离株与受体的黏附与新生儿低出生体重（LBW）呈强负相关（优势比[95%置信区间]，5.2[1.1-25.1]）。在孕妇的血浆样本中，针对每株胎盘分离株的特异性免疫球蛋白G（抗VSA（PAP））水平与针对所有其他分离株的抗VSA（PAP）抗体水平呈强相关性（P<0.05），且在所有分离株中均随产次增加而升高（P<0.01）。相反，黏附抑制抗体与分离株或抗VSA（PAP）抗体水平无关。
胎盘寄生虫对硫酸软骨素受体的黏附水平是LBW的一个重要危险因素。寄生虫的异质性表明它们由混合黏附表型组成，能够诱导针对一系列不同且重叠靶点的免疫反应。
