Norris D E, Levine J F, Menard M, Nakagaki K, Howard P, Apperson C S
Department of Microbiology, Pathology and Parasitology, North Carolina State University, Raleigh 27607, USA.
J Wildl Dis. 1996 Apr;32(2):300-14. doi: 10.7589/0090-3558-32.2.300.
The reservoir competence of the raccoon (Procyon lotor) for the Lyme disease spirochete (Borrelia burgdorferi) was evaluated in the laboratory during September 1991 to April 1993. Five raccoons were exposed to spirochete-infected (JD1 and Wisconsin 210 Wise strains) Ixodes scapularis nymphs (20/raccoon). A second feeding of spirochete-infected (Wisconsin 210 Wise strain) nymphs (20/raccoon) was performed with four of the original raccoons. Xenodiagnosis with cohorts of I. scapularis larvae (300/cohort) or nymphs (150/cohort) that were periodically placed on each animal was used to detect infection. We examined 1943 engorged ticks by a indirect immunofluorescence monoclonal antibody assay, but no spirochetes were detected. After exposure to spirochete-infected ticks, blood samples were collected at approximately weekly intervals and ear-skin biopsy samples were taken from each animal every third week. These tissues were placed in Barbour-Stoenner-Kelly media. Spirochetes were isolated in cultures of skin (wk 3, 5, 9, 81, and 83) and blood (wk 5, 8, 9, 11, and 12) of one raccoon and the skin (wk 28 and 31) of another raccoon. Antibody response of each animal was monitored through enzyme-linked immunosorbent assays and immunoblotting of blood serum against B. burgdorferi proteins. Except for one animal, raccoons did not have an antibody response until they were fed upon by a second cohort of infected I. scapularis nymphs. Based on Western blot analyses, raccoons exposed to B. burgdorferi via tick bite responded to the 31- (OspA) and 34-KDa (OspB) antigens. Response to other antigens varied among raccoons. Based on our results raccoons may be inefficient reservoirs for B. burgdorferi. Although some raccoons can become infected with B. burgdorferi, they may not transfer the infection to attached ticks.
1991年9月至1993年4月期间，在实验室对浣熊（北美浣熊）作为莱姆病螺旋体（伯氏疏螺旋体）储存宿主的能力进行了评估。将5只浣熊暴露于感染螺旋体（JD1和威斯康星210 Wise菌株）的肩突硬蜱若虫（每只浣熊20只）。对4只原来的浣熊再次进行感染螺旋体（威斯康星210 Wise菌株）若虫的叮咬（每只浣熊20只）。通过定期将成群的肩突硬蜱幼虫（每组300只）或若虫（每组150只）放置在每只动物身上进行异种诊断，以检测感染情况。我们通过间接免疫荧光单克隆抗体检测法检查了1943只饱血蜱，但未检测到螺旋体。在暴露于感染螺旋体的蜱之后，大约每周采集一次血液样本，每只动物每隔一周进行一次耳部皮肤活检取样。将这些组织置于巴伯-斯托纳-凯利培养基中。在一只浣熊的皮肤（第3、5、9、81和83周）和血液（第5、8、9、11和12周）以及另一只浣熊的皮肤（第28和31周）培养物中分离出了螺旋体。通过酶联免疫吸附测定和针对伯氏疏螺旋体蛋白的血清免疫印迹法监测每只动物的抗体反应。除一只动物外，浣熊在被第二批感染的肩突硬蜱若虫叮咬之前没有抗体反应。基于蛋白质印迹分析，通过蜱叮咬暴露于伯氏疏螺旋体的浣熊对31 kDa（外膜蛋白A）和34 kDa（外膜蛋白B）抗原产生反应。对其他抗原的反应在浣熊之间有所不同。根据我们的结果，浣熊可能是伯氏疏螺旋体的低效储存宿主。尽管一些浣熊可以感染伯氏疏螺旋体，但它们可能不会将感染传播给附着的蜱。
