Shahabuddin M, Pimenta P F
Medical Entomology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Proc Natl Acad Sci U S A. 1998 Mar 31;95(7):3385-9. doi: 10.1073/pnas.95.7.3385.
Penetration of the mosquito midgut epithelium is obligatory for the further development of Plasmodium parasites. Therefore, blocking the parasite from invading the midgut wall disrupts the transmission of malaria. Despite such a pivotal role in malaria transmission, the cellular and molecular interactions that occur during the invasion are not understood. Here, we demonstrate that the ookinetes of Plasmodium gallinaceum, which is related closely to the human malaria parasite Plasmodium falciparum, selectively invade a cell type in the Aedes aegypti midgut. These cells, unlike the majority of the cells in the midgut, do not stain with a basophilic dye (toluidine blue) and are less osmiophilic. In addition, they contain minimal endoplasmic reticulum, lack secretory granules, and have few microvilli. Instead, these cells are highly vacuolated and express large amounts of vesicular ATPase. The enzyme is associated with the apical plasma membrane, cytoplasmic vesicles, and tubular extensions of the basal membrane of the invaded cells. The high cost of insecticide use in endemic areas and the emergence of drug resistant malaria parasites call for alternative approaches such as modifying the mosquito to block the transmission of malaria. One of the targets for such modification is the parasite receptor on midgut cells. A step toward the identification of this receptor is the realization that malaria parasites invade a special cell type in the mosquito midgut.
疟原虫的进一步发育必须穿透蚊子的中肠上皮。因此，阻止寄生虫侵入中肠壁可中断疟疾传播。尽管在疟疾传播中起着关键作用，但入侵过程中发生的细胞和分子相互作用尚不清楚。在这里，我们证明，与人类疟原虫恶性疟原虫密切相关的鸡疟原虫动合子选择性地侵入埃及伊蚊中肠的一种细胞类型。这些细胞与中肠中的大多数细胞不同，不会被嗜碱性染料（甲苯胺蓝）染色，且嗜锇性较低。此外，它们含有最少的内质网，缺乏分泌颗粒，且微绒毛较少。相反，这些细胞高度空泡化，并大量表达囊泡ATP酶。该酶与被侵入细胞的顶端质膜、细胞质囊泡和基底膜的管状延伸相关。流行地区使用杀虫剂的成本高昂以及耐药疟原虫的出现，需要诸如改造蚊子以阻断疟疾传播等替代方法。这种改造的目标之一是中肠细胞上的寄生虫受体。朝着鉴定这种受体迈出的一步是认识到疟原虫侵入蚊子中肠的一种特殊细胞类型。
