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17. The genus Anaplasma: new challenges after reclassification

Author

Kocan, K. M., De La Fuente, José, Cabezas Cruz, Alejandro, Oklahoma State University [Stillwater], Instituto de Investigación en Recursos Cinegéticos (IREC), Institut National de la Santé et de la Recherche Médicale (INSERM), Université Lille Nord de France (COMUE), Walter R. Sitlington Endowed Chair for Food Animal Research BFU2011-23896, European Project: 278976,EC:FP7:HEALTH,FP7-HEALTH-2011-two-stage,ANTIGONE(2011), and Oklahoma State University [Stillwater] (OSU)

Subjects
Anaplasmosis, tick-borne, animal diseases, [SDV]Life Sciences [q-bio], parasitic diseases, bacterial infections and mycoses, anaplasma marginale, anaplasma phagocytophylum, anaplasmataceae
Abstract

Contribution: Drafting of the manuscript.; International audience; Summary The genus Anaplasmais one of four distinct genera in the family Anaplasmataceae, which are obligate intracellular pathogens vectored by ticks and found exclusively within parasitophorous vacuoles in the host cell cytoplasm. The 2001 reclassification of the order Rickettsiales expanded the genus Anaplasma, which previously contained pathogens that were host specific for ruminants (A. marginale, A. centrale and A. bovis), by adding A. phagocytophilum, a unification of three organisms previously classified as Ehrlichia (E. equi, E. phagocytophila and the unnamed agent of human granulocytic ehrlichiosis). Also included in the genus Anaplasma were A. bovis (formerly E. bovis), A. platys (formerly E. platys) and Aegyptianella pullorum. Despite the genomic relatedness of the regrouped organisms, many aspects of their biology are diverse, including their host specificity, host cell preferences, major surface proteins (MSPs) and tick vectors. This review focuses on the two most important pathogens: A. marginale, which causes bovine anaplasmosis, and A. phagocytophilum, the aetiologic agent of tick-borne fever in sheep and human granulocytic anaplasmosis, an emerging tick-borne disease of humans. For both pathogens, strain diversity is much greater than previously recognised. While MSPs were found to be useful in phylogenetic studies and strain identification, highly conserved MSPs were found to affect the specificity of serologic tests. Comparison of these two important pathogens highlights the challenges and insight derived from reclassification and molecular analysis, both of which have implications for the development and evaluation of diagnosis and control strategies.

Published
2015

19. Seroprevalence of anaplasmosis among cattle in Switzerland in 1998 and 2003: no evidence of an emerging disease

Author

Dreher, U M, Hofmann-Lehmann, Regina, Meli, Marina L, Regula, G, Cagienard, A Y, Stärk, K D C, Doherr, M G, Filli, F, Hässig, Michael, Braun, Ueli, Kocan, K M, Lutz, H, University of Zurich, and Lutz, H

Subjects
10187 Department of Farm Animals, 630 Agriculture, 3400 General Veterinary, 2404 Microbiology, 11404 Department of Clinical Diagnostics and Services, 570 Life sciences, biology, 11434 Center for Clinical Studies
Published
2005
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20. Serologic cross-reactivity between Anaplasma marginale and Anaplasma phagocytophilum

Author

Dreher, U M, de la Fuente, J, Hofmann-Lehmann, Regina, Meli, Marina L, Pusterla, N, Kocan, K M, Woldehiwet, Z, Braun, Ueli, Regula, G, Staerk, K D C, Lutz, H, University of Zurich, and Lutz, H

Subjects
10187 Department of Farm Animals, 2403 Immunology, 630 Agriculture, 11404 Department of Clinical Diagnostics and Services, 2723 Immunology and Allergy, 570 Life sciences, biology, 1308 Clinical Biochemistry, 2726 Microbiology (medical)
Published
2005

21. Study to Compare the Efficacy of Three Oxytetracycline Regimens for the Treatment of Anaplasma Marginale Carrier Status in Beef Cattle

Author

Coetzee, J. F., Apley, M. D., Kocan, K. M., Knowles, D. P., and Donkersgoed, J. V.

Abstract

Anaplasmosis is a blood-borne disease of cattle and other ruminants caused by Anaplasma marginale. Animals recovering from clinical anaplasmosis and those treated with therapeutic doses of oxytetracycline remain persistently infected with microscopically undetectable levels of the organism. These animals serve as reservoirs of the disease which can be spread mechanically or through arthropod vectors. Tetracyclines are the only compounds approved for treatment of acute anaplasmosis infections in the United States; however no compounds are approved for eliminating the carrier state. This has contributed to the restricted movement of cattle from endemic areas of the US to anaplasmosis-free territories such as Canada. Anaplasmosis is estimated to cost the US cattle industry $100 million per year, with some estimating the cost of resticted trade to be near $300 million annually. The objective of this study was to compare the effects of three oxytetracycline treatment regimens on eliminating Anaplasma marginale infection from carrier beef steers., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2004

Published
2004
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23. Sequence analysis of the msp4 gene of Anaplasma phagocytophilum strains

Author

de la Fuente, J, Massung, R F, Wong, S J, Chu, F K, Lutz, H, Meli, M, von Loewenich, F D, Grzeszczuk, A, Torina, A, Caracappa, S, Mangold, A J, Naranjo, V, Stuen, S, Kocan, K M, de la Fuente, J, Massung, R F, Wong, S J, Chu, F K, Lutz, H, Meli, M, von Loewenich, F D, Grzeszczuk, A, Torina, A, Caracappa, S, Mangold, A J, Naranjo, V, Stuen, S, and Kocan, K M

Abstract

The causative agent of human granulocytic ehrlichiosis was recently reclassified as Anaplasma phagocytophilum, unifying previously described bacteria that cause disease in humans, horses, dogs, and ruminants. For the characterization of genetic heterogeneity in this species, the homologue of Anaplasma marginale major surface protein 4 gene (msp4) was identified, and the coding region was PCR amplified and sequenced from a variety of sources, including 50 samples from the United States, Germany, Poland, Norway, Italy, and Switzerland and 4 samples of A. phagocytophilum-like organisms obtained from white-tailed deer in the United States. Sequence variation between strains of A. phagocytophilum (90 to 100% identity at the nucleotide level and 92 to 100% similarity at the protein level) was higher than in A. marginale. Phylogenetic analyses of msp4 sequences did not provide phylogeographic information but did differentiate strains of A. phagocytophilum obtained from ruminants from those obtained from humans, dogs, and horses. The sequence analysis of the recently discovered A. phagocytophilum msp2 gene corroborated these results. The results reported here suggest that although A. phagocytophilum-like organisms from white-tailed deer may be closely related to A. phagocytophilum, they could be more diverse. These results suggest that A. phagocytophilum strains from ruminants could share some common characteristics, including reservoirs and pathogenicity, which may be different from strains that infect humans.

Published
2005

24. Genetic diversity of anaplasma species major surface proteins and implications for anaplasmosis serodiagnosis and vaccine development

Author

de la Fuente, J, Lew, A, Lutz, H, Meli, Marina L; https://orcid.org/0000-0002-3609-2416, Hofmann-Lehmann, R; https://orcid.org/0000-0001-9750-4296, Shkap, V, Molad, T, Mangold, A J, Almazán, C, Naranjo, V, Gortázar, C, Torina, A, Caracappa, S, García-Pérez, A L, Barral, M, Oporto, B, Ceci, L, Carelli, G, Blouin, E F, Kocan, K M, de la Fuente, J, Lew, A, Lutz, H, Meli, Marina L; https://orcid.org/0000-0002-3609-2416, Hofmann-Lehmann, R; https://orcid.org/0000-0001-9750-4296, Shkap, V, Molad, T, Mangold, A J, Almazán, C, Naranjo, V, Gortázar, C, Torina, A, Caracappa, S, García-Pérez, A L, Barral, M, Oporto, B, Ceci, L, Carelli, G, Blouin, E F, and Kocan, K M

Abstract

The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several pathogens of veterinary and human medical importance. An understanding of the diversity of Anaplasma major surface proteins (MSPs), including those MSPs that modulate infection, development of persistent infections, and transmission of pathogens by ticks, is derived in part, by characterization and phylogenetic analyses of geographic strains. Information concerning the genetic diversity of Anaplasma spp. MSPs will likely influence the development of serodiagnostic assays and vaccine strategies for the control of anaplasmosis.

Published
2005

47. Subolesin/Akirin Vaccines for the Control of Arthropod Vectors and Vectorborne Pathogens.

Author

Fuente, J., Moreno ‐ Cid, J. A., Galindo, R. C., Almazan, C., Kocan, K. M., Merino, O., Perez de la Lastra, J. M., Estrada ‐ Peña, A., and Blouin, E. F.

Subjects
ARBOVIRUS diseases, VIRAL vaccines, MOSQUITO vectors, TICKS as carriers of disease, VIRUS disease transmission, ANAPLASMA phagocytophilum, VIRAL antigens
Abstract

Diseases transmitted by arthropod vectors such as mosquitoes, ticks and sand flies greatly impact human and animal health, and therefore, their control is important for the eradication of vectorborne diseases ( VBD). Vaccination is an environmentally friendly alternative for vector control that allows control of several VBD by targeting their common vector. Recent results have suggested that subolesin ( SUB) and its orthologue in insects, akirin ( AKR) are good candidate antigens for the control of arthropod vector infestations and pathogen infection. SUB was discovered as a tick-protective antigen in Ixodes scapularis. Vaccination trials with recombinant SUB/ AKR demonstrated effective control of arthropod vector infestations in various hard and soft tick species, mosquitoes, sand flies, poultry red mites and sea lice by reducing their numbers, weight, oviposition, fertility and/or moulting. SUB/ AKR vaccination also reduced tick infection with tickborne pathogens, Anaplasma phagocytophilum, A. marginale, Babesia bigemina and Borrelia burgdorferi. The effect of vaccination on different hosts, vector species, developmental stages and vectorborne pathogen infections demonstrated the feasibility of SUB/ AKR universal vaccines for the control of multiple vector infestations and for reduction in VBD. [ABSTRACT FROM AUTHOR]

Published
2013
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48. Flow cytometric evaluation of selected antimicrobial efficacy for clearance of Anaplasma marginale in short-term erythrocyte cultures.

Author

Coetzee, J. F., Apley, M. D., Kocan, K. M., and Jones, D. E.

Subjects
RICKETTSIA, RICKETTSIACEAE, ANAPLASMA marginale, ANAPLASMA, ANTI-infective agents, CATTLE infections
Abstract

The tick-borne rickettsia, Anaplasma marginale, causes the economically important cattle disease anaplasmosis. Once infected, cattle remain lifelong carriers. Herein, we used flow cytometry to test the efficacy of three antimicrobials; oxytetracycline, imidocarb and enrofloxacin against Virginia (VGN) or Oklahoma (OK) A. marginale isolates in short-term erythrocyte cultures. Parasite viability was assessed using the vital dye hydroethidine (HE), which is detectable when living organisms convert HE to ethidium bromide. Viability of A. marginale in selected cultures was determined by subinoculation into susceptible calves. Data were analyzed by MANOVA, Tukey-Kramer honest significant difference and Wilcoxon rank sum tests. Receiver operating characteristic (ROC) analysis was used to correlate results with culture infectivity. Enrofloxacin inhibited A. marginale in a dose dependent manner. Surprisingly, higher concentrations of imidocarb were less effective than lower concentrations against A. marginale with significant differences ( P < 0.05) observed between the two isolates. Oxytetracycline was the least active drug tested. Cultures infected with the OK isolate exposed to 4.0 μg/mL enrofloxacin and those of the VGN and OK isolates exposed to 1.0 μg/mL imidocarb were sterilized. This is the first in vitro study demonstrating the efficacy of enrofloxacin against A. marginale. Furthermore, these data indicate that flow cytometry is a useful assay for screening antimicrobials against A. marginale. [ABSTRACT FROM AUTHOR]

Published
2006
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