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Leishmaniasis is a serious health problem in many countries, and continues expanding to new geographic areas including Europe and USA. This disease, caused by parasites of Leishmania spp. and transmitted by phlebotomine sand flies, causes up to 1.3 million new cases each year and despite efforts toward its functional dissection and treatment it causes 20-50 thousands deaths annually. Dependence of susceptibility to leishmaniasis on sex and host's genes was observed in humans and in mouse models. Several laboratories defined in mice a number of Lmr (Leishmania major response) genetic loci that control functional and pathological components of the response to and outcome of L. major infection. However, the development of its most aggressive form, visceral leishmaniasis, which is lethal if untreated, is not yet understood. Visceral leishmaniasis is caused by infection and inflammation of internal organs. Therefore, we analyzed the genetics of parasite load, spread to internal organs, and ensuing visceral pathology. Using a new PCR-based method of quantification of parasites in tissues we describe a network-like set of interacting genetic loci that control parasite load in different organs. Quantification of Leishmania parasites in lymph nodes, spleen and liver from infected F2 hybrids between BALB/c and recombinant congenic strains CcS-9 and CcS-16 allowed us to map two novel parasite load controlling Leishmania major response loci, Lmr24 and Lmr27. We also detected parasite-controlling role of the previously described loci Lmr4, Lmr11, Lmr13, Lmr14, Lmr15, and Lmr25, and describe 8 genetic interactions between them. Lmr14, Lmr15, Lmr25, and Lmr27 controlled parasite load in liver and lymph nodes. In addition, Leishmania burden in lymph nodes but not liver was influenced by Lmr4 and Lmr24. In spleen, parasite load was controlled by Lmr11 and Lmr13. We detected a strong effect of sex on some of these genes. We also mapped additional genes controlling splenomegaly and hepatomegaly. This resulted in a systematized insight into genetic control of spread and load of Leishmania parasites and visceral pathology in the mammalian organism.
- MeSH
- interakce hostitele a parazita MeSH
- Leishmania major * MeSH
- leishmanióza viscerální genetika parazitologie MeSH
- myši MeSH
- parazitární zátěž * MeSH
- pohlavní dimorfismus MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Roost ectoparasites are believed to have a negative impact on fitness of their hosts as birds or mammals. Previous studies were mostly focussed on the synchronization between reproduction cycles of ectoparasites and hosts living in infested roosts. However, to date, it has not been examined how fast ectoparasites colonize new, non-infested roosts and thus increasing the impact on the local populations of hosts. The parasite-host model was studied, including bat bugs Cimex pipistrelli and soprano pipistrelles Pipistrellus pygmaeus, where bat behaviour was observed which tended to reduce the parasite load in bat roosts. We investigated (1) whether bats change their roosting behaviour when we discontinued synchronization of their reproduction and the life cycle of the bat bugs and (2) how fast and which stages of bat bugs reoccupy cleaned roosts. In a 3-year field experiment, we removed all bat bugs from six bat boxes in each spring. Pipistrelles bred young in all non-infested boxes during these 3 years. In addition, 8 years of regular observations before this experiment indicate that bats avoided breeding in the same bat boxes at all. Bat bugs were found again in clean boxes in mid-May. However, their densities did not maximise before the beginning of June, before parturition. A re-appearance of bugs was observed after 21-56 days after the first bat visit. Adult bugs, mainly females, colonised cleaned boxes first though at the same time there were a lot of younger and smaller instars in non-manipulated roosts in the vicinity.
- MeSH
- Chiroptera parazitologie fyziologie MeSH
- interakce hostitele a parazita * MeSH
- parazitární zátěž * MeSH
- sexuální chování zvířat MeSH
- štěnice růst a vývoj MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Two genotypes of the intestinal parasite Ceratonova shasta infect Oncorhynchus mykiss: genotype 0 results in a chronic infection with low mortality while genotype IIR causes disease with high mortality. We determined parasite load and the relative expression of six immune factors (IgT, IgM, IL-6, IL-8, IL-10, IFNG) in fish infected with either genotype over 29 days post-exposure. In genotype IIR infections the host responded with upregulation of inflammatory and regulatory cytokines. In contrast, genotype 0 infection did not elicit an inflammatory response and expression of IFNG and IL-10 was lower. Antibody expression was upregulated in both infections but appeared to have limited efficacy in the virulent genotype IIR infections. Histologically, in genotype 0 infections the parasite migrated through the tissue layers causing inflammation but minimal damage to the mucosal epithelium, which contrasts with the severe pathology found in genotype IIR infections.
- MeSH
- cytokiny genetika metabolismus MeSH
- genotyp * MeSH
- imunoglobulin M krev MeSH
- imunoglobuliny krev MeSH
- interakce hostitele a parazita MeSH
- Myxozoa genetika patogenita MeSH
- nemoci ryb imunologie MeSH
- Oncorhynchus mykiss imunologie MeSH
- parazitární nemoci u zvířat imunologie MeSH
- parazitární zátěž MeSH
- pohyb buněk MeSH
- rybí proteiny krev MeSH
- sliznice imunologie MeSH
- virulence MeSH
- zánět imunologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
BACKGROUND: Recently, human intervention enabled the introduction of Barbus barbus from the Rhône River basin into the Barbus meridionalis habitats of the Argens River. After an introduction event, parasite loss and lower infection can be expected in non-native hosts in contrast to native species. Still, native species might be endangered by hybridization with the incomer and the introduction of novel parasite species. In our study, we aimed to examine metazoan parasite communities in Barbus spp. populations in France, with a special emphasis on the potential threat posed by the introduction of novel parasite species by invasive B. barbus to local B. meridionalis. METHODS: Metazoan parasite communities were examined in B. barbus, B. meridionalis and their hybrids in three river basins in France. Microsatellites were used for the species identification of individual fish. Parasite abundance, prevalence, and species richness were compared. Effects of different factors on parasite infection levels and species richness were tested using GLM. RESULTS: Metazoan parasites followed the expansion range of B. barbus and confirmed its introduction into the Argens River. Here, the significantly lower parasite number and lower levels of infection found in B. barbus in contrast to B. barbus from the Rhône River supports the enemy release hypothesis. Barbus barbus × B. meridionalis hybridization in the Argens River basin was confirmed using both microsatellites and metazoan parasites, as hybrids were infected by parasites of both parental taxa. Trend towards higher parasite diversity in hybrids when compared to parental taxa, and similarity between parasite communities from the Barbus hybrid zone suggest that hybrids might represent "bridges" for parasite infection between B. barbus and B. meridionalis. Risk of parasite transmission from less parasitized B. barbus to more parasitized B. meridionalis indicated from our study in the Argens River might be enhanced in time as higher infection levels in B. barbus from the Rhône River were revealed. Hybrid susceptibility to metazoan parasites varied among the populations and is probably driven by host-parasite interactions and environmental forces. CONCLUSIONS: Scientific attention should be paid to the threatened status of the endemic B. meridionalis, which is endangered by hybridization with the invasive B. barbus, i.e. by genetic introgression and parasite transmission.
- MeSH
- biodiverzita * MeSH
- chiméra klasifikace genetika růst a vývoj parazitologie MeSH
- Cyprinidae klasifikace genetika růst a vývoj parazitologie MeSH
- mikrosatelitní repetice MeSH
- parazitární zátěž MeSH
- paraziti klasifikace izolace a purifikace MeSH
- řeky MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Francie MeSH
The use of biotherapies as intervention in murine infection with Trypanosoma cruzi is a possible means to understand the effects of these highly diluted medications. This study evaluated the effects of biotherapies that were prepared from rabbit serum uninfected (BSNI13c group) and chronically infected with Y strain of T. cruzi (BSI13c group), dynamization 13c, in mice experimentally infected. Parasitological, histopathological, and immunological parameters were evaluated. BSNI13c group exhibited the best outcome, including decreases in parasitemia and parasite load/inflammation in the heart, with pronounced Th1 response on days 8 and 12 after infection (a.i.) that was attributable to decrease in IL-4 concentrations, with no increases in TNF-α and IFN-γ, associated to decrease in IL-17A compared to control. In contrast, BSI13c group did not exhibit alterations in parasitemia but a significant decrease in parasite load/inflammation in the heart, with pronounced Th2 response on day 12 a.i. that was attributable to increase in IL-4 concentrations, with no changes in TNF-α and IFN-γ, associated to decrease in IL-17A compared to control. This study suggest that biotherapies that were prepared from rabbit serum uninfected and chronically infected with T. cruzi differentially modulate the immune system in mice infected with this protozoan, providing evidence of the actions of these medications.
- MeSH
- antiparazitární látky farmakologie terapeutické užití MeSH
- biologická terapie MeSH
- biologické přípravky farmakologie terapeutické užití MeSH
- Chagasova nemoc * farmakoterapie imunologie parazitologie patologie MeSH
- cytokiny krev MeSH
- homeopatie * MeSH
- interleukin-17 krev MeSH
- interleukin-4 krev MeSH
- modely nemocí na zvířatech MeSH
- myši MeSH
- parazitemie farmakoterapie MeSH
- srdce parazitologie MeSH
- Trypanosoma cruzi * MeSH
- zánět krev MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
In the present study, we determine the presence of parasites in fish larvae collected from nearshore waters along the northern and central coast of Chile. The parasites were identified to the lowest possible taxonomic level based on morphological and molecular analyses. The fish sample was composed of 5 574 fish larvae. Of these, 3% harboured only larval ectoparasitic copepods whereas no endoparasites were found in the 1 141 fish evaluated for this group of parasites. The parasitic copepods collected were initially classified as 'morphotypes' according to differences in morphological characteristics. They were then analysed using molecular techniques based on the 28S and COI genes. Seven morphotypes of parasitic copepods (mostly at chalimus stages) were recognised: two of the morphotypes belonged to Pennellidae Burmeister, 1835, three to Caligidae Burmeister, 1835 and two were not identified. Only five morphotypes of copepods were analysed using molecular sequences, which confirmed the existence of six species: two pennellids of the genus Trifur Wilson, 1917 and two caligids of the genus Caligus Müller, 1785, plus two additional species that were morphologically different from these taxa. The pennellids were present in several fish species, being generally more prevalent than the caligids, in both the central and northern localities of Chile. Multispecies infections in larval fish were infrequent (< 1%). We conclude that fish larvae were rich in parasites, considering that these hosts exhibited small body sizes and were very young. We suggest that fish larvae could play a role, as intermediate hosts, in the life cycle of the parasitic copepods found.
- MeSH
- Copepoda anatomie a histologie genetika klasifikace růst a vývoj MeSH
- fylogeneze MeSH
- larva parazitologie MeSH
- parazitární zátěž * MeSH
- polymerázová řetězová reakce MeSH
- ryby * parazitologie růst a vývoj MeSH
- sekvenční analýza DNA MeSH
- statistika jako téma MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Chile MeSH
The genes of major histocompatibility complex (MHC) provide an excellent opportunity to study host-parasite relationships because they are expected to evolve in response to parasites and variation in parasite communities. In this study, we investigated the potential role of parasite-mediated selection acting on MHC class IIB (DAB) genes in European chub (Squalius cephalus) natural populations. We found significant differences between populations in metazoan parasites, neutral and adaptive genetic diversities. The analyses based on pairwise data revealed that populations with dissimilar MHC allelic profiles were geographically distant populations with significantly different diversity in microsatellites and a dissimilar composition of parasite communities. The results from the generalized estimating equations method (GEE) on the level of individuals revealed that metazoan parasite load in European chub was influenced by the diversity of DAB alleles as well as by the diversity of neutral genetic markers and host traits reflecting condition and immunocompetence. The multivariate co-inertia analysis showed specific associations between DAB alleles and parasite species. DAB1-like alleles were more involved in associations with ectoparasites, while DAB3-like alleles were positively associated with endoparasites which could suggest potential differences between DAB genes caused by different selection pressure. Our study revealed that parasite-mediated selection is not the only variable affecting MHC diversity in European chub; however, we strongly support the role of neutral processes as the main driver of DAB diversity across populations. In addition, our study contributes to the understanding of the evolution of MHC genes in wild living fish.
- MeSH
- alely MeSH
- Cyprinidae genetika MeSH
- divoká zvířata MeSH
- genetická variace * MeSH
- hlavní histokompatibilní komplex genetika MeSH
- interakce hostitele a parazita MeSH
- mikrosatelitní repetice genetika MeSH
- nemoci ryb parazitologie MeSH
- parazitární nemoci u zvířat epidemiologie genetika parazitologie MeSH
- paraziti MeSH
- selekce (genetika) * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa epidemiologie MeSH
Wormy mice in a hybrid zone have been interpreted as evidence of low hybrid fitness, such that parasites contribute to species separation. However, because of its natural heterogeneity, observations of parasite load must be numerous with good field area coverage. We sampled 689 mice from 107 localities across the Bavaria-Bohemia region of the European house mouse hybrid zone and calculated their hybrid indices using 1401 diagnostic single nucleotide polymorphisms (SNPs). We tested whether hybrids have greater or lesser diversity and load of parasite helminths than additive expectations, performing load analyses on the four most common taxa. We found hybrids have significantly reduced diversity and load of each of the commonest helminths; rarer helminths further support reduced load. Although within-locality comparisons have little power, randomization tests show the repeated pattern is unlikely to be due to local parasite heterogeneity, and simulations show a patch of low parasite diversity is unlikely to fall by chance just so in the field area, such that it produces the observed effects. Our data therefore contradict the idea that helminths reduce hybrid fitness through increased load. We discuss a vicariant Red Queen model that implies immune genes tracking parasites will escape Dobzhansky-Muller incompatibilities, generating hybrid variants untargeted by parasites.
- MeSH
- biodiverzita MeSH
- cizopasní červi imunologie MeSH
- hybridizace genetická * MeSH
- jednonukleotidový polymorfismus MeSH
- myši genetika imunologie parazitologie MeSH
- parazitární zátěž * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši genetika imunologie parazitologie MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- Acari klasifikace růst a vývoj MeSH
- Argasidae klasifikace růst a vývoj MeSH
- Chiroptera parazitologie MeSH
- infestace ektoparazity epidemiologie parazitologie veterinární MeSH
- infestace roztoči epidemiologie parazitologie MeSH
- interakce hostitele a parazita MeSH
- prevalence MeSH
- roztoči klasifikace růst a vývoj MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Geografické názvy
- Polsko MeSH
Cutaneous leishmaniasis due to Leishmania tropica is increasingly documented in Europe and the Middle East. Besides its specific vector, Phlebotomus sergenti, permissive Phlebotomus sand flies are suspected as potential vectors of L. tropica. We investigated the susceptibility of two widely distributed species, Phlebotomus perniciosus and Phlebotomus tobbi. Laboratory-reared sand flies were infected experimentally with L. tropica strains differing in lipophosphoglycan epitopes, geographical distribution and epidemiology. High infection rates, heavy parasite loads and fully developed late-stage infections including colonization of the stomodeal valve were observed in all parasite-vector combinations. Our findings demonstrate that P. perniciosus and P. tobbi are susceptible to different L. tropica strains and may play a role in their circulation in endemic foci of Europe, the Middle East and North Africa.
- MeSH
- anatomické struktury zvířat parazitologie MeSH
- hmyz - vektory parazitologie MeSH
- hostitelská specificita * MeSH
- Leishmania tropica růst a vývoj MeSH
- parazitární zátěž MeSH
- Phlebotomus parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH