Institute for Comparative Tropical Medicine and Parasitology, Ludwig-Maximilians-Universität München, Munich, Germany.
Ticks Tick Borne Dis. 2011 Dec;2(4):204-8. doi: 10.1016/j.ttbdis.2011.09.002. Epub 2011 Oct 17.
Anaplasma phagocytophilum is an obligate intracellular bacterium causing granulocytic anaplasmosis in dogs, horses, and humans and tick-borne fever of ruminants. The bacterium has been detected in a variety of other mammals including wild ruminants without overt clinical signs of disease. Isolates in cell culture have been obtained from humans, dogs, horses, sheep, and ticks, but no strain from wild ruminants exists in cell culture in Europe. From September to November 2010, EDTA blood samples were collected from the jugular vein of 19 shot roe deer from a forest in southern Germany. The presence of specific A. phagocytophilum DNA was demonstrated with a real-time PCR targeting the msp2 gene in all 19 animals. Subsequently, blood cells were used to inoculate the tick cell line IDE8. The first infected IDE8 cells were detected in Giemsa-stained smears 57 days post inoculation. Only one roe deer yielded a positive culture which has been propagated for 9 consecutive passages thus far representing 228 days in culture. Further analysis of the A. phagocytophilum strain was performed by PCR followed by sequencing for the partial 16S rRNA, groEL, msp2, and msp4 genes. Phylogenetic topology of groEL and msp4 sequences placed the roe deer isolate in close proximity to sequences available from roe deer and goats from the neighbouring Alpine regions of Austria and Switzerland, and of msp2 with other ruminant species. This represents the first isolation of A. phagocytophilum in a tick cell line directly from an infected wild ruminant reservoir host, Capreolus capreolus, in Europe. The availability of a cultured A. phagocytophilum strain isolated from roe deer will allow us to study the biological characteristics and the pathogenic potential of this strain as well as to compare its host tropism and its genetic and antigenetic properties with those of other A. phagocytophilum strains from other animal species.
嗜吞噬细胞无形体是一种专性细胞内细菌，可引起犬、马和人类粒细胞无形体病以及反刍动物蜱传发热。该细菌已在多种其他哺乳动物中检测到，包括无明显疾病临床症状的野生反刍动物。在细胞培养物中已从人类、犬、马、绵羊和蜱中分离出分离株，但在欧洲的细胞培养物中不存在来自野生反刍动物的菌株。2010 年 9 月至 11 月，从德国南部森林中采集了 19 只被射杀的狍子颈静脉的 EDTA 血样。在所有 19 只动物中，使用针对 msp2 基因的实时 PCR 证明了特定的嗜吞噬细胞无形体 DNA 的存在。随后，使用血细胞接种 tick 细胞系 IDE8。接种后 57 天，在吉姆萨染色涂片上首次检测到感染的 IDE8 细胞。只有一只狍子产生了阳性培养物，迄今为止已连续传代 9 次，培养时间为 228 天。通过 PCR 进行进一步分析，随后对部分 16S rRNA、groEL、msp2 和 msp4 基因进行测序。groEL 和 msp4 序列的系统发育拓扑结构将鹿源分离株置于与奥地利和瑞士邻近阿尔卑斯地区的鹿和山羊的序列以及 msp2 与其他反刍动物物种的序列非常接近的位置。这是在欧洲首次从受感染的野生反刍动物库宿主鹿直接在 tick 细胞系中分离出嗜吞噬细胞无形体。从鹿中分离出培养的嗜吞噬细胞无形体株，将使我们能够研究该菌株的生物学特性和致病潜力，并将其宿主嗜性以及遗传和抗原特性与其他来自不同动物物种的嗜吞噬细胞无形体株进行比较。
