Rikihisa Yasuko
Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, 1925 Coffey Road, Columbus, OH 43210, USA.
Curr Opin Microbiol. 2006 Feb;9(1):95-101. doi: 10.1016/j.mib.2005.12.003. Epub 2006 Jan 6.
Anaplasma (formerly Ehrlichia) phagocytophilum and Ehrlichia chaffeensis, upon infection of humans, replicate in host leukocyte granulocytes and monocytes/macrophages, respectively. These unusual Gram-negative bacteria lack genes for biosynthesis of the lipopolysaccharide and peptidoglycan that activate host leukocytes. Caveolae-mediated endocytosis directs A. phagocytophilum and E. chaffeensis to an intracellular compartment secluded from oxygen-dependent and -independent killing. Furthermore, these bacteria orchestrate a remarkable series of events that culminate in suppression of NADPH oxidase, phagocyte activation and differentiation pathways, apoptosis, and interferon-gamma signaling in host leukocytes. They offer a fascinating example of how pathogens employ intricate strategies to usurp and subvert host cell function.
嗜吞噬无形体（原称埃立克体）和查菲埃立克体感染人类后，分别在宿主白细胞粒细胞和单核细胞/巨噬细胞中复制。这些不同寻常的革兰氏阴性菌缺乏可激活宿主白细胞的脂多糖和肽聚糖生物合成基因。小窝介导的内吞作用将嗜吞噬无形体和查菲埃立克体导向一个与依赖氧和不依赖氧的杀伤机制隔离的细胞内区室。此外，这些细菌精心策划了一系列显著事件，最终导致宿主白细胞中NADPH氧化酶受抑制、吞噬细胞激活和分化途径受阻、细胞凋亡以及干扰素-γ信号传导受抑制。它们为病原体如何运用复杂策略篡夺和颠覆宿主细胞功能提供了一个引人入胜的例子。
