Klíšťata sají obrovské množství krve, která je jejich jediným zdrojem živin a energie. Přesný enzymatický mechanismus zpracování krve ve střevě klíšťat však kupodivu nebyl donedávna vůbec znám. Náš komplexní molekulární model trávení hostitelského hemoglobinu u klíštěte obecného (Ixodes ricinus) poprvé odhalil analogii enzymatického aparátu s krevsajícími ploštěnci a hlísticemi, a zároveň tato znalost představuje zásadní poznatek pro účinný boj s klíšťaty a jimi přenášenými patogeny., Ticks (in this case Ixodidae and Argasidae) feed on enormous amounts of host blood, which provides their ultimate source of energy and nutrients. There has been only limited evidence on the exact molecular mechanisms of blood digestion in ticks. For the first time, our complex enzymatic model of proteolytic digestion in the Common Tick (Ixodes ricinus) reveals the analogy of tick intestinal proteolysis with bloodfeeding platyhelminthes and nematodes and presents a future application potential in tick or tick-borne pathogen interventions., and Daniel Sojka.
Antiparasitic allogrooming in two adults of Red Fox (Vulpes vulpes) was observed in the Javorie Mountains in Slovakia on 18th April 2016. This rare observation was documented by photographs and video. In this context, the occurrence of ticks on Red Foxes and in fox faeces in Europe is briefly reviewed and discussed. and Ivan Literák.
Laboratory animals (mice and guinea pigs) were infected with the isolates of Coxiella burnetii (Derrick, 1939) obtained from bovine milk (M18 and M35) and the ticks Ixodes ricinus (Linnaeus, 1758) and Dermacentor marginatus (Sulzer, 1776) (Kl3 and Kl6, respectively), and with the reference strain Nine Mile. Neither mortality nor lethality occurred with the mice. Antibody response in mice infected with isolates from milk was lower (1 : 16-512) than that from ticks (1 : 32-4096). Onset of seropositivity also occurred later - on the 10th day post-infection (p.i.) for M18 and M35 in comparison with the 7th day for Kl3 and Kl6. In guinea pigs, infection manifested by fever. The fever was less evident in guinea pigs infected with isolates from milk (39.5-40.1°C) than in guinea pigs infected with isolates from ticks (39.5-40.6°C). Partially engorged females of Dermacentor reticulatus (Fabricius, 1794) were inoculated with isolates M18 and Kl3 . No differences in the multiplication of C. burnetii in haemocytes between these two isolates were ascertained.
Genetic distances and phylogenetic clustering are calculated for sympatric populations of Rhipicephalus pusillus (Gil Collado) 1939 ticks, using cuticular hydrocarbon analysis and several statistical tools (stepwise discriminant analysis, Nei’s genetic distance using different sets of compounds, and Cavalli-Sforza’s Brownian motion model). Discriminant analysis on genic frequencies permits the detection of the most ancient geographic relationships between the populations, while the genetic distance method determines current evolutive affinities. However, methods based on quantitative estimation provide a poor resolution. Genetic distances are very high in the populations studied, suggesting a strong reproductive isolation of the specimens involved.
The purpose of the workshop, which took place in 8-15 June 2008, was to train scientists to manage and exploit large EST datasets as well as compare whole genome sequences, with the aim of faciliting the application of genomic technologies to ticks and tickbornepathogens. The course provided an overview of the mehods used to sequence, assemble, and annotate tick borne disease related genomes and EST datasets. and Libor Grubhoffer.
Lyme borreliosis (LB) is a serious infectious disease of humans and some domestic animals in temperate regions of the Northern Hemisphere. It is caused by certain spirochetes in the Borrelia burgdorferi sensu lato (s.l.) species complex. The complex consists of 11 species (genospecies). Borrelia burgdorferi sensu stricto (s.s.), Borrelia garinii and Borrelia afzelii are the major agents of human disease. Borrelia burgdorferi s.l. species are transmitted mainly by ticks belonging to the Ixodes ricinus species complex plus a few additional species not currently assigned to the complex. B. burgdorferi infections may produce an acute or chronic disease with a wide array of clinical symptoms such as erythema migrans (EM), carditis, arthritis, neuroborreliosis, and acrodermatitis chronica atrophicans (ACA). Differences in LB spirochetes ''genospecies'' and strains/isolates determine the occurrence and severity of this multi-system disease. Accurate and reliable identification of the LB spirochetes in ticks as well as knowledge of their prevalence are essential for prevention against the disease and development of an effective vaccine. An overview of the knowledge of molecular factors with emphasis on potential protein-carbohydrate interactions in the tick-borrelia system is the main focus of this review.
Animal-free set-up enables a new series of experiments; from basic research describing trophic dependences of ticks to testing anti-tick compounds. Exploiting the cunning use of silicone membrane to mimic a host skin, in combination with perfumes that resemble the scents of a living animal, scientists from the Institute of Parasitology of the Biology Centre of the CAS gradually reveal what makes the tick a parasite. The membrane system is also intended for applied research, for testing anti-tick vaccines/compounds. and Jan Perner, Matěj Kučera, Petr Kopáček.
Ixodid ticks remain attached to their hosts for several days to weeks. During this extended feeding process new proteins involved in the modulation of host immune responses are expressed in tick salivary glands. In our study a stimulatory or inhibitory effect of salivary gland extracts (SGE) of unfed and partially fed female Ixodes ricinus (Linnaeus, 1758), female and male Amblyomma variegatum (Fabricius, 1794) and Rhipicephalus appendiculatus Neumann, 1901 ticks on human lymphocyte proliferation induced by Concanavalin A (ConA) and phytohaemagglutinin (PHA), respectively, was investigated. SGE of all female ticks examined suppressed proliferation of ConA-induced lymphocytes; highly significant suppression was observed in the presence of unfed I. ricinus and 9-day fed A. variegatum SGE. SGE of partially fed A. variegatum and I. ricinus females suppressed PHA responses of lymphocytes. Lymphocytes showed reduced PHA and ConA responses in the presence of SGE of unfed and 2-day fed R. appendiculatus females, while SGE of 6-day fed females enhanced PHA responses, but reduced their ConA responses; generally SGE of 2-day fed females displayed the strongest inhibition. Amblyomma variegatum male SGE slightly enhanced PHA, but significantly reduced ConA responses of lymphocytes and their inhibitory effect increased during feeding. SGE of unfed and 2-day fed R. appendiculatus males enhanced PHA and ConA responses and those of 6-day fed males suppressed lymphocyte proliferation. The results suggest that (i) species- and sex-specific differences exist in the effects of tick salivary gland antigens on human lymphocyte proliferation and (ii) effect of SGE on human lymphocyte responses to mitogens varies depending on the tick feeding status.