A soft tick Ornithodoros moubata salivary protein OmCI is a potent inhibitor to prevent avian complement activation

Publication date: Available online 6 December 2019Source: Ticks and Tick-borne DiseasesAuthor(s): Amber M. Frye, Thomas M. Hart, Danielle M. Tufts, Sanjay Ram, Maria A. Diuk-Wasser, Peter Kraiczy, Anna M. Blom, Yi-Pin LinAbstractComplement is a key first line innate host defense system in the blood of vertebrates. Upon activation, this powerful defense mechanism can elicit inflammatory responses, lyse non-self-cells, or mark them for opsonophagocytic removal. Blood-feeding arthropods thus require the ability to block host complement activation in the bloodmeal to prevent undesired cell or tissue damage during feeding. The soft tick Ornithodoros moubata produces a complement inhibitory protein, OmCI. This protein binds to a mammalian complement protein C5 and blocks further activation of complement cascades, which results in the prevention of complement-mediated bacterial killing through membrane attack complex. Interestingly, the amino acids involved in OmCI binding are highly conserved among mammalian and avian C5, but the ability of this protein to inhibit the complement from birds remains unclear. Here we demonstrated that OmCI is capable of preventing quail complement-mediated erythrocyte lysis, inhibiting the capability of this animal’s complement to eliminate a serum-sensitive Lyme disease bacterial strain. We also found that the ability of OmCI to inhibit quail complement-mediated killing of Lyme disease bacteria can be extended to different domestic and wild bir...
Source: Ticks and Tick borne Diseases - Category: Zoology Source Type: research

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In this study, multilocus sequence typing (MLST) was employed to investigate the local population structure of B. garinii in Ixodes ricinus ticks. The study took place in a natural wetland in Slovakia, temporally encompassing spring and autumn bird migration periods as well as the breeding period of resident birds. In total, we examined 369 and 255 ticks collected from 78 birds and local vegetation, respectively. B. burgdorferi s.l. was detected in 43.4% (160/369) of ticks recovered from birds and in 26.3% (67/255) of questing ticks, respectively. Considering the ticks from bird hosts, the highest prevalence was found for ...
Source: International Journal of Environmental Research and Public Health - Category: Environmental Health Authors: Tags: Article Source Type: research
H, Heylen D Abstract Wild birds are frequently exposed to the zoonotic tick-borne bacteria Borrelia burgdorferi sensu lato (s.l.), and some bird species act as reservoirs for some Borrelia genospecies. Studying the tropism of Borrelia in the host, how it is sequestered in different organs, and whether it is maintained in circulation and/or in the host's skin is important to understand pathogenicity, infectivity to vector ticks and reservoir competency.We evaluated tissue dissemination of Borrelia in blackbirds (Turdus merula) and great tits (Parus major), naturally and experimentally infected with Borrelia genospe...
Source: Microbial Ecology - Category: Microbiology Authors: Tags: Microb Ecol Source Type: research
In this study, bird species migrating through Bulgaria were investigated as carriers of zoonotic pathogens. In total, 706 birds belonging to 46 species were checked for the presence of various bacterial pathogens (Campylobacter, Yersin ia, Salmonella, Listeria, Escherichia coli, Staphylococcus aureus, Francisella tularensis, Coxiella burnetii, Borrelia burgdorferi, and Brucella spp.). From 673 birds we investigated fecal samples, from the remaining 33, blood samples. We detected Campylobacter 16S rDNA gene in 1.3% of birds, but no ne were of pathogenic Campylobacter jejuni and Campylobacter coli species. Escherichia coli 1...
Source: Canadian Journal of Microbiology - Category: Microbiology Authors: Source Type: research
In this study, we used this chamber model and showed that I. scapularis ticks will not only acquire bovine blood but human and quail blood as well. The latter two are the incidental host and an avian host of Lyme borreliae, respectively. We also investigated the roles that BBA52 and Lp6.6 play in promoting spirochete survival in nymphal ticks fed on human or quail blood. After feeding on human blood, spirochete burdens in ticks infected with an lp6.6-deficient B. burgdorferi were significantly reduced, while bba52-deficient spirochete burdens in ticks remained unchanged, similar to the wild-type strain. No strain showed a ...
Source: Ticks and Tick borne Diseases - Category: Zoology Source Type: research
Publication date: Available online 16 February 2018 Source:Ticks and Tick-borne Diseases Author(s): Ana Cláudia Norte, David Costantini, Pedro Miguel Araújo, Marcel Eens, Jaime Albino Ramos, Dieter Heylen By draining resources, microparasites can negatively affect the host fitness, which in turn can result in reduced transmission when virulence leads to reductions in host population size. Therefore, for a microparasite to persist in nature, the level of harm it can do to its host is expected to be limited. We tested this hypothesis for tick-borne Borrelia burgdorferi sensu lato (s.l.) infections in the black...
Source: Ticks and Tick borne Diseases - Category: Zoology Source Type: research
CONCLUSIONS: The obtained results show that the pheasants had developed antibodies to the investigated tick-borne agents. For this reason, they seem to be involved in the epidemiology of the studied tick-borne bacteria. PMID: 28378988 [PubMed - in process]
Source: Annals of Agricultural and Environmental Medicine : AAEM - Category: Environmental Health Authors: Tags: Ann Agric Environ Med Source Type: research
Mepron, a thick liquid antimicrobial drug used to treat Babesia and malaria, as well as a fungal infection called Pneumocystitis carinii. In 2011, the United Kingdom stopped requiring that dogs brought into the country be inspected for ticks. Earlier this year, several dogs tested positive for babesia, a malaria-like disease transmitted to ticks that previously had only been found in foreign. These dogs had never left the U.K. While babesiosis is a new worry to U.K. dog owners, it's been a threat to human beings for years -- it just hasn't become a health-scare-of-the-week like Zika, West Nile, avian and swine flu. Most...
Source: Healthy Living - The Huffington Post - Category: Consumer Health News Source Type: news
Conclusion: Our study suggests that the tick, and not the pathogen, controls the early stages of host choice behaviour.
Source: Parasites and Vectors - Category: Microbiology Authors: Source Type: research
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