TY - JOUR
T1 - Isolation and establishment of the raccoon Ehrlichia-like agent in tick cell culture
AU - Munderloh, Ulrike G.
AU - Yabsley, Michael J.
AU - Murphy, Staci M.
AU - Luttrell, M. Page
AU - Howerth, Elizabeth W.
PY - 2007/9
Y1 - 2007/9
N2 - Feral animals are reservoirs of emerging human pathogens, as well as carriers of closely related wildlife diseases. The latter may interfere with epidemiologic studies by inducing cross-reactive antibodies, or by providing false positive signals in PCR based tests. We cultured a novel intracellular bacterium from the blood of two raccoons (Procyon lotor): RAC413 and RAC414. RAC413 had been experimentally inoculated with blood from a wild-caught raccoon, and provided the material for a blood passage into RAC414. The microbes grew in Ixodes scapularis (black-legged tick) cells, line ISE6, inoculated either with the leukocyte or erythrocyte fraction of anticoagulated blood. Giemsa-stained cells sampled two and three months after initial inoculation of the cultures revealed inclusions similar to those of Ehrlichia sp., except that individual bacteria commonly were elongated and clustered within endosomes. Electronmicroscopy confirmed the presence of irregularly shaped bacteria with evenly granular bacterioplasm bounded by a unit membrane. 16S rDNA sequencing identified the microbes as the raccoon Ehrlichia-like agent previously detected in feral raccoons from Georgia, United States. In conclusion, the availability of a culture isolate of this agent will facilitate future studies to determine its biology, epidemiologic significance, vector association, and host range. The Ehrlichia-like agent infecting raccoons joins a growing list of tick-borne agents cultivable in tick cells.
AB - Feral animals are reservoirs of emerging human pathogens, as well as carriers of closely related wildlife diseases. The latter may interfere with epidemiologic studies by inducing cross-reactive antibodies, or by providing false positive signals in PCR based tests. We cultured a novel intracellular bacterium from the blood of two raccoons (Procyon lotor): RAC413 and RAC414. RAC413 had been experimentally inoculated with blood from a wild-caught raccoon, and provided the material for a blood passage into RAC414. The microbes grew in Ixodes scapularis (black-legged tick) cells, line ISE6, inoculated either with the leukocyte or erythrocyte fraction of anticoagulated blood. Giemsa-stained cells sampled two and three months after initial inoculation of the cultures revealed inclusions similar to those of Ehrlichia sp., except that individual bacteria commonly were elongated and clustered within endosomes. Electronmicroscopy confirmed the presence of irregularly shaped bacteria with evenly granular bacterioplasm bounded by a unit membrane. 16S rDNA sequencing identified the microbes as the raccoon Ehrlichia-like agent previously detected in feral raccoons from Georgia, United States. In conclusion, the availability of a culture isolate of this agent will facilitate future studies to determine its biology, epidemiologic significance, vector association, and host range. The Ehrlichia-like agent infecting raccoons joins a growing list of tick-borne agents cultivable in tick cells.
KW - Ehrlichia
KW - Ixodes
KW - Raccoon
KW - Tick
KW - Tick cell culture
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UR - http://www.scopus.com/inward/citedby.url?scp=35148824976&partnerID=8YFLogxK
U2 - 10.1089/vbz.2007.0640
DO - 10.1089/vbz.2007.0640
M3 - Article
C2 - 17867909
AN - SCOPUS:35148824976
SN - 1530-3667
VL - 7
SP - 418
EP - 425
JO - Vector-Borne and Zoonotic Diseases
JF - Vector-Borne and Zoonotic Diseases
IS - 3
ER -