Leenstra Tjalling, ter Kuile Feiko O, Kariuki Simon K, Nixon Christian P, Oloo Aggrey J, Kager Piet A, Kurtis Jonathan D
Centre for Vector Biology and Control Research, Kenya Medical Research Institute, Kisumu, Kenya.
J Infect Dis. 2003 Jul 15;188(2):297-304. doi: 10.1086/376508. Epub 2003 Jul 1.
In areas where Plasmodium falciparum malaria is endemic, parasite density, morbidity, and mortality decrease with increasing age, which supports the view that years of cumulative exposure are necessary for the expression of maximal protective immunity. Developmental changes in the host also have been implicated in the expression of maximal resistance. To further evaluate the contribution of host developmental factors in malaria resistance, we examined the relationship between P. falciparum parasitemia and pubertal development in a cross-sectional sample of 12-18-year-old schoolgirls from an area of intense transmission in western Kenya. Among pubertal girls, dehydroepiandrosterone sulfate (DHEAS) levels were significantly associated with decreased parasite density, even after adjustment for age. DHEAS levels also were related to increased hemoglobin levels, even after accounting for age and other determinants of hemoglobin level. These findings support the hypothesis that host pubertal development, independent of age and, by proxy, cumulative exposure, is necessary for maximal expression of resistance to malarial infection and morbidity, as assessed by hemoglobin level.
在恶性疟原虫疟疾流行地区,寄生虫密度、发病率和死亡率随年龄增长而降低,这支持了以下观点:多年的累积接触对于最大程度地表达保护性免疫力是必要的。宿主的发育变化也与最大抵抗力的表达有关。为了进一步评估宿主发育因素在疟疾抵抗力中的作用,我们在肯尼亚西部一个高传播地区的12至18岁女学生横断面样本中,研究了恶性疟原虫血症与青春期发育之间的关系。在青春期女孩中,即使在调整年龄后,硫酸脱氢表雄酮(DHEAS)水平也与寄生虫密度降低显著相关。即使在考虑年龄和血红蛋白水平的其他决定因素后,DHEAS水平也与血红蛋白水平升高有关。这些发现支持了这样的假设:宿主青春期发育独立于年龄以及(由此推断的)累积接触,对于通过血红蛋白水平评估的对疟疾感染和发病的最大抵抗力表达是必要的。