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il-4/5 signalling plays an important role during litomosoides sigmodontis infection, influencing both immune system regulation and tissue pathology in the thoracic cavity.approximately 100 million people suffer from filarial diseases including lymphatic filariasis (elephantiasis), onchocerciasis (river blindness) and loiasis. these diseases are amongst the most devastating of the neglected tropical diseases in terms of social and economic impact. moreover, many infection-induced immune mechanisms in the host, their relationship to disease-related symptoms and the development of pathology within the site of infection remain unclear. to improve on current drug ther ...201728859850
lipid profiling of the filarial nematodes onchocerca volvulus, onchocerca ochengi and litomosoides sigmodontis reveals the accumulation of nematode-specific ether phospholipids in the host.onchocerciasis, a neglected tropical disease prevalent in western and central africa, is a major health problem and has been targeted for elimination. the causative agent for this disease is the human parasite onchocerca volvulus. onchocerca ochengi and litomosoides sigmodontis, infectious agents of cattle and rodents, respectively, serve as model organisms to study filarial nematode infections. biomarkers to determine infection without the use of painful skin biopsies and microscopic identifica ...201728743489
migratory phase of litomosoides sigmodontis filarial infective larvae is associated with pathology and transient increase of s100a9 expressing neutrophils in the lung.filarial infections are tropical diseases caused by nematodes of the onchocercidae family such as mansonella perstans. the infective larvae (l3) are transmitted into the skin of vertebrate hosts by blood-feeding vectors. many filarial species settle in the serous cavities including m. perstans in humans and l. sigmodontis, a well-established model of filariasis in mice. l. sigmodontis l3 migrate to the pleural cavity where they moult into l4 around day 9 and into male and female adult worms arou ...201728486498
combination of worm antigen and proinsulin prevents type 1 diabetes in nod mice after the onset of insulitis.animal studies demonstrated that administration of helminth products can protect from autoimmune diseases. however, the success of such administrations is limited in the case of type 1 diabetes, as protection is only provided if the administration is started before the development of insulitis. in this study we investigated whether inclusion of helminth antigen administrations to an antigen-specific treatment with proinsulin improves the protective effect by triggering non-specific regulatory im ...201626898311
patency of litomosoides sigmodontis infection depends on toll-like receptor 4 whereas toll-like receptor 2 signalling influences filarial-specific cd4(+) t-cell responses.balb/c mice develop a patent state [release of microfilariae (mf), the transmission life-stage, into the periphery] when exposed to the rodent filariae litomosoides sigmodontis. interestingly, only a portion of the infected mice become patent, which reflects the situation in human individuals infected with wuchereria bancrofti. since those individuals had differing filarial-specific profiles, this study compared differences in immune responses between mf(+) and mf(-) infected balb/c mice. we dem ...201626714796
glyceradehyde-3-phosphate dehydrogenase as a suitable vaccine candidate for protection against bacterial and parasitic diseases.the enzyme glyceraldehyde-3-p-dehydrogenase (gapdh) has been identified as having other properties in addition to its key role in glycolysis. the ability of gapdh to bind to numerous extracellular matrices, modulation of host-immune responses, a role in virulence and surface location has prompted numerous investigators to postulate that gapdh may be a good vaccine candidate for protection against numerous pathogens. although immune responses against gapdh have been described for many microorgani ...201626686572
endothelial cells release soluble factors that support the long-term survival of filarial worms in vitro.the inability to maintain filarial nematodes in long-term in vitro culture greatly limits research into the basic biology of these parasites and hinders in vitro screening of novel anti-filarial agents. in this study, we sought to characterize nutrients that promote the long-term survival of filarial worms in vitro. using microfilariae (mf) obtained from gerbils infected with litomosoides sigmodontis, a filarial parasite of rodents, we found that dulbecco's modified eagle medium (dmem) supplemen ...201627565719
stage-specific proteomes from onchocerca ochengi, sister species of the human river blindness parasite, uncover adaptations to a nodular lifestyle.despite 40 years of control efforts, onchocerciasis (river blindness) remains one of the most important neglected tropical diseases, with 17 million people affected. the etiological agent, onchocerca volvulus, is a filarial nematode with a complex lifecycle involving several distinct stages in the definitive host and blackfly vector. the challenges of obtaining sufficient material have prevented high-throughput studies and the development of novel strategies for disease control and diagnosis. he ...201627226403
nod2 dependent neutrophil recruitment is required for early protective immune responses against infectious litomosoides sigmodontis l3 larvae.nucleotide-binding oligomerization domain-containing protein 2 (nod2) recognizes muramyl dipeptide (mdp) of bacterial cell walls, triggering nfκb-induced pro-inflammation. as most human pathogenic filariae contain wolbachia endobacteria that synthesize the mdp-containing cell wall precursor lipid ii, nod2's role during infection with the rodent filaria litomosoides sigmodontis was investigated. in nfκb reporter-cells, worm-extract containing wolbachia induced nod2 and nod1. nod2-deficient mice i ...201628004792
filarial infection or antigen administration improves glucose tolerance in diet-induced obese mice.helminths induce type 2 immune responses and establish an anti-inflammatory milieu in their hosts. this immunomodulation was previously shown to improve diet-induced insulin resistance which is linked to chronic inflammation. in the current study, we demonstrate that infection with the filarial nematode litomosoides sigmodontis increased the eosinophil number and alternatively activated macrophage abundance within epididymal adipose tissue (eat) and improved glucose tolerance in diet-induced obe ...201627544668
fat-associated lymphoid clusters control local igm secretion during pleural infection and lung inflammation.fat-associated lymphoid clusters (falc) are inducible structures that support rapid innate-like b-cell immune responses in the serous cavities. little is known about the physiological cues that activate falcs in the pleural cavity and more generally the mechanisms controlling b-cell activation in falcs. here we show, using separate models of pleural nematode infection with litomosoides sigmodontis and altenaria alternata induced acute lung inflammation, that inflammation of the pleural cavity ra ...201627582256
neutropenic mice provide insight into the role of skin-infiltrating neutrophils in the host protective immunity against filarial infective larvae.our knowledge and control of the pathogenesis induced by the filariae remain limited due to experimental obstacles presented by parasitic nematode biology and the lack of selective prophylactic or curative drugs. here we thought to investigate the role of neutrophils in the host innate immune response to the infection caused by the litomosoides sigmodontis murine model of human filariasis using mice harboring a gain-of-function mutation of the chemokine receptor cxcr4 and characterized by a prof ...201627111140
ten weeks of infection with a tissue-invasive helminth protects against local immune complex-mediated inflammation, but not cutaneous type i hypersensitivity, in previously sensitized mice.in this study, we evaluated the effect chronic helminth infection has on allergic disease in mice previously sensitized to ova. ten weeks of infection with litomosoides sigmodontis reduced immunological markers of type i hypersensitivity, including ova-specific ige, basophil activation, and mast cell degranulation. despite these reductions, there was no protection against immediate clinical hypersensitivity following intradermal ova challenge. however, late-phase ear swelling, due to type iii hy ...201526324775
a histochemical study of the nras/let-60 activity in filarial nematodes.control and elimination of filarial pathogens is a central focus of major global health efforts directed at parasitic diseases of developing countries. accomplishment of these goals would be markedly enhanced by the enhanced destruction of the adult stage of filariae. the identification of new, more quantitative biomarkers that correlate with mortality or chemotherapeutic damage to adult filariae, would greatly facilitate, for example, the development of new macrofilaricides.201526130134
dna vaccine encoding the moonlighting protein onchocerca volvulus glyceraldehyde-3-phosphate dehydrogenase (ov-gapdh) leads to partial protection in a mouse model of human filariasis.river blindness, caused by the filarial parasite onchocerca volvulus, is a major socio-economic and public health problem in sub-saharan africa. in january 2015, the onchocerciasis vaccine for africa (tova) initiative has been launched with the aim of providing new tools to complement mass drug administration (mda) of ivermectin, thereby promoting elimination of onchocerciasis in africa. in this context we here present onchocerca volvulus glyceraldehyde-3-phosphate dehydrogenase (ov-gapdh) as a ...201526320419
development of patent litomosoides sigmodontis infections in semi-susceptible c57bl/6 mice in the absence of adaptive immune responses.one of the most advantageous research aspects of the murine model of filariasis, litomosoides sigmodontis, is the availability of mouse strains with varying susceptibility to the nematode infection. in c57bl/6 mice, l. sigmodontis worms are largely eliminated in this strain by day 40 post-infection and never produce their offspring, microfilariae (mf). this provides a unique opportunity to decipher potential immune pathways that are required by filariae to achieve a successful infection. in this ...201526209319
histamine 1 receptor blockade enhances eosinophil-mediated clearance of adult filarial worms.filariae are tissue-invasive nematodes that cause diseases such as elephantiasis and river blindness. the goal of this study was to characterize the role of histamine during litomosoides sigmodontis infection of balb/c mice, a murine model of filariasis. time course studies demonstrated that while expression of histidine decarboxylase mrna increases throughout 12 weeks of infection, serum levels of histamine exhibit two peaks-one 30 minutes after primary infection and one 8 weeks later. interest ...201526204515
litomosoides sigmodontis induces tgf-β receptor responsive, il-10-producing t cells that suppress bystander t-cell proliferation in mice.helminth parasites suppress immune responses to prolong their survival within the mammalian host. thereby not only helminth-specific but also nonhelminth-specific bystander immune responses are suppressed. here, we use the murine model of litomosoides sigmodontis infection to elucidate the underlying mechanisms leading to this bystander t-cell suppression. when ot-ii t cells specific for the third-party antigen ovalbumin are transferred into helminth-infected mice, these cells respond to antigen ...201526138667
immune recognition of onchocerca volvulus proteins in the human host and animal models of onchocerciasis.onchocerca volvulus is a tissue-dwelling, vector-borne nematode parasite of humans and is the causative agent of onchocerciasis or river blindness. natural infections of balb/c mice with litomosoides sigmodontis and of cattle with onchocerca ochengi were used as models to study the immune responses to o. volvulus-derived recombinant proteins (ovalt-2, ovnlt-1, ov103 and ov7). the humoral immune response of o. volvulus-infected humans against ovalt-2, ovnlt-1 and ov7 revealed pronounced immunoglo ...201524721822
chronic filarial infection provides protection against bacterial sepsis by functionally reprogramming macrophages.helminths immunomodulate their hosts and induce a regulatory, anti-inflammatory milieu that prevents allergies and autoimmune diseases. helminth immunomodulation may benefit sepsis outcome by preventing exacerbated inflammation and severe pathology, but the influence on bacterial clearance remains unclear. to address this, mice were chronically infected with the filarial nematode litomosoides sigmodontis (l.s.) and the outcome of acute systemic inflammation caused by i.p. escherichia coli inject ...201525611587
litomosoides sigmodontis: a jird urine metabolome study.the neglected tropical disease onchocerciasis affects more than 35 million people worldwide with over 95% in africa. disease infection initiates from the filarial parasitic nematode onchocerca volvulus, which is transmitted by the blackfly vector simulium sp. carrying infectious l3 larvae. new treatments and diagnostics are required to eradicate this parasitic disease. herein, we describe that a previously discovered biomarker for onchocerciasis, n-acetyltyramine-o-glucuronide (natog) is also pr ...201526573416
pleural cavity type 2 innate lymphoid cells precede th2 expansion in murine litomosoides sigmodontis infection.recently, a family of innate cells has been identified that respond to il-25 and il-33 in murine intestinal helminths. termed type 2 innate lymphoid cells (ilc2s) they facilitate the development of th2 responses responsible for helminth clearance. we evaluated these cells in a tissue-invasive helminth model. using litomosides sigmodontis (a strong th2 polarizing filarial infection) we observed a robust th2 response in the pleural cavity, where adult worms reside, marked by increased levels of il ...201526394284
extracellular onchocerca-derived small rnas in host nodules and blood.micrornas (mirnas), a class of short, non-coding rna can be found in a highly stable, cell-free form in mammalian body fluids. specific mirnas are secreted by parasitic nematodes in exosomes and have been detected in the serum of murine and dog hosts infected with the filarial nematodes litomosoides sigmodontis and dirofilaria immitis, respectively. here we identify extracellular, parasite-derived small rnas associated with onchocerca species infecting cattle and humans.201525623184
exosomes secreted by nematode parasites transfer small rnas to mammalian cells and modulate innate immunity.in mammalian systems rna can move between cells via vesicles. here we demonstrate that the gastrointestinal nematode heligmosomoides polygyrus, which infects mice, secretes vesicles containing micrornas (mirnas) and y rnas as well as a nematode argonaute protein. these vesicles are of intestinal origin and are enriched for homologues of mammalian exosome proteins. administration of the nematode exosomes to mice suppresses type 2 innate responses and eosinophilia induced by the allergen alternari ...201425421927
repurposing of approved drugs from the human pharmacopoeia to target wolbachia endosymbionts of onchocerciasis and lymphatic filariasis.lymphatic filariasis and onchocerciasis are debilitating diseases caused by parasitic filarial nematodes infecting around 150 million people throughout the tropics with more than 1.5 billion at risk. as with other neglected tropical diseases, classical drug-discovery and development is lacking and a 50 year programme of macrofilaricidal discovery failed to deliver a drug which can be used as a public health tool. recently, antibiotic targeting of filarial wolbachia, an essential bacterial symbio ...201425516838
co-infection restrains litomosoides sigmodontis filarial load and plasmodial p. yoelii but not p. chabaudi parasitaemia in mice.infection with multiple parasite species is clearly the norm rather than the exception, in animals as well as in humans. filarial nematodes and plasmodium spp. are important parasites in human public health and they are often co-endemic. interactions between these parasites are complex. the mechanisms underlying the modulation of both the course of malaria and the outcome of filarial infection are poorly understood. despite increasing activity in recent years, studies comparing co- and mono-infe ...201424717449
st2 deficiency does not impair type 2 immune responses during chronic filarial infection but leads to an increased microfilaremia due to an impaired splenic microfilarial clearance.interactions of the th2 cytokine il-33 with its receptor st2 lead to amplified type 2 immune responses. as type 2 immune responses are known to mediate protection against helminth infections we hypothesized that the lack of st2 would lead to an increased susceptibility to filarial infections.201424663956
nematode-induced interference with vaccination efficacy targets follicular t helper cell induction and is preserved after termination of infection.one-third of the human population is infected with parasitic worms. to avoid being eliminated, these parasites actively dampen the immune response of their hosts. this immune modulation also suppresses immune responses to third-party antigens such as vaccines. here, we used litomosoides sigmodontis-infected balb/c mice to analyse nematode-induced interference with vaccination. chronic nematode infection led to complete suppression of the humoral response to thymus-dependent vaccination. thereby ...201425255463
eotaxin-1 is involved in parasite clearance during chronic filarial infection.eosinophil migration as key feature of helminth infection is increased during infection with filarial nematodes. in a mouse model of filariasis, we investigated the role of the eosinophil-attracting chemokine eotaxin-1 on disease outcome. balb/c and eotaxin-1(-/-) mice were infected with the rodent filaria litomosoides sigmodontis, and parasitic parameters, cellular migration to the site of infection, and cellular responsiveness were investigated. we found increased parasite survival but unaffec ...201424112106
localization of a filarial phosphate permease that is up-regulated in response to depletion of essential wolbachia endobacteria.wolbachia of filarial nematodes are essential, obligate endobacteria. when depleted by doxycycline worm embryogenesis, larval development and worm survival are inhibited. the molecular basis governing the endosymbiosis between wolbachia and their filarial host is still being deciphered. in rodent filarial nematode litomosoides sigmodontis, a nematode encoded phosphate permease gene (ls-ppe-1) was up-regulated at the mrna level in response to wolbachia depletion and this gene promises to have an ...201424480589
comparative analysis of the secretome from a model filarial nematode (litomosoides sigmodontis) reveals maximal diversity in gravid female parasites.filarial nematodes (superfamily filarioidea) are responsible for an annual global health burden of ∼6.3 million disability-adjusted life-years, which represents the greatest single component of morbidity attributable to helminths affecting humans. no vaccine exists for the major filarial diseases, lymphatic filariasis and onchocerciasis; in part because research on protective immunity against filariae has been constrained by the inability of the human-parasitic species to complete their lifecycl ...201424958169
immunization with brugia malayi hsp70 protects mice against litomosoides sigmodontis challenge infection.more than 1·5 billion people are at risk of being infected with filarial nematodes worldwide. therapy and control of transmission are mainly based on mass drug distribution. as these drugs have to be administered annually or biannually and might be loosing their efficacy, a vaccine against filariae is an alternative approach to chemotherapy. in the current study, we have analysed the potential of brugia malayi heat shock protein 70 (bmhsp70) as a vaccine candidate in a murine helminth infection. ...201424359133
the secreted triose phosphate isomerase of brugia malayi is required to sustain microfilaria production in vivo.human lymphatic filariasis is a major tropical disease transmitted through mosquito vectors which take up microfilarial larvae from the blood of infected subjects. microfilariae are produced by long-lived adult parasites, which also release a suite of excretory-secretory products that have recently been subject to in-depth proteomic analysis. surprisingly, the most abundant secreted protein of adult brugia malayi is triose phosphate isomerase (tpi), a glycolytic enzyme usually associated with th ...201424586152
fitness cost of litomosoides sigmodontis filarial infection in mite vectors; implications of infected haematophagous arthropod excretory products in host-vector interactions.filariae are a leading cause of infections which are responsible for serious dermatological, ocular, and vascular lesions. infective third stage larvae (l3) are transmitted through the bite of a haematophagous vector. litomosoides sigmodontis is a well-established model of filariasis in the mouse, with the vector being the mite ornithonyssus bacoti. the aim of the study was to analyse the filarial infection in mites to determine the consequences of filarial infection in the blood-feeding and the ...201324089685
th2 cell-intrinsic hypo-responsiveness determines susceptibility to helminth infection.the suppression of protective type 2 immunity is a principal factor driving the chronicity of helminth infections, and has been attributed to a range of th2 cell-extrinsic immune-regulators. however, the intrinsic fate of parasite-specific th2 cells within a chronic immune down-regulatory environment, and the resultant impact such fate changes may have on host resistance is unknown. we used il-4gfp reporter mice to demonstrate that during chronic helminth infection with the filarial nematode lit ...201323516361
comparative analysis of macrophage migration inhibitory factors (mifs) from the parasitic nematode onchocerca volvulus and the free-living nematode caenorhabditis elegans.the macrophage migration inhibitory factors (mifs) from the filarial parasite onchocerca volvulus (ovmif) were compared to the mifs from the free-living nematode caenorhabditis elegans (cemif) with respect to molecular, biochemical and immunological properties. except for cemif-4, all other mifs demonstrated tautomerase activity. surprisingly, ovmif-1 displayed oxidoreductase activity. the strongest immunostaining for ovmif-1 was observed in the outer cellular covering of the adult worm body, th ...201323820606
vaccination with intestinal tract antigens does not induce protective immunity in a permissive model of filariasis.antigens obtained from the intestinal tract of filarial nematodes have been proposed as potential safe and effective vaccine candidates. because they may be 'hidden' from the immune response during natural infection, yet accessible by antibodies induced by vaccination, intestinal antigens may have a low potential for eliciting allergic responses when vaccinating previously infected individuals. despite prior promising data, vaccination with intestinal antigens has yet to be tested in a permissiv ...201323792131
basophils help establish protective immunity induced by irradiated larval vaccination for filariasis.basophils are increasingly recognized as playing important roles in the immune response toward helminths. in this study, we evaluated the role of basophils in vaccine-mediated protection against filariae, tissue-invasive parasitic nematodes responsible for diseases such as elephantiasis and river blindness. protective immunity and immunological responses were assessed in balb/c mice vaccinated with irradiated l3 stage larvae and depleted of basophils with weekly injections of anti-cd200r3 antibo ...201323777951
the clpp peptidase of wolbachia endobacteria is a novel target for drug development against filarial infections.filarial infections causing lymphatic filariasis or onchocerciasis (river blindness) can be treated with antibiotics (e.g. doxycycline) targeting the essential endosymbiotic wolbachia bacteria. the depletion of wolbachia inhibits worm development and causes worm death. available antibiotics have restrictions for use in children and pregnant or breastfeeding women. therefore, alternative antibiotics are needed that can be given to all members of the population and that are active with a shorter t ...201323584755
t-cell-derived, but not b-cell-derived, il-10 suppresses antigen-specific t-cell responses in litomosoides sigmodontis-infected mice.il-10, a cytokine with pleiotropic functions is produced by many different cells. although il-10 may be crucial for initiating protective th2 responses to helminth infection, it may also function as a suppressive cytokine preventing immune pathology or even contributing to helminth-induced immune evasion. here, we show that b cells and t cells produce il-10 during murine litomosoides sigmodontis infection. il-10-deficient mice produced increased amounts of l. sigmodontis-specific ifn-γ and il-13 ...201323529858
chronic helminth infection reduces basophil responsiveness in an il-10-dependent manner.basophils play a key role in the development and effector phases of type 2 immune responses in both allergic diseases and helminth infections. this study shows that basophils become less responsive to ige-mediated stimulation when mice are chronically infected with litomosoides sigmodontis, a filarial nematode, and schistosoma mansoni, a blood fluke. although excretory/secretory products from microfilariae of l. sigmodontis suppressed basophils in vitro, transfer of microfilariae into mice did n ...201222461700
immunization with l. sigmodontis microfilariae reduces peripheral microfilaraemia after challenge infection by inhibition of filarial embryogenesis.lymphatic filariasis and onchocerciasis are two chronic diseases mediated by parasitic filarial worms causing long term disability and massive socioeconomic problems. filariae are transmitted by blood-feeding mosquitoes that take up the first stage larvae from an infected host and deliver it after maturation into infective stage to a new host. after closure of vector control programs, disease control relies mainly on mass drug administration with drugs that are primarily effective against first ...201222413031
functional characterization and immune recognition of the extracellular superoxide dismutase from the human pathogenic parasite onchocerca volvulus (ovec-sod).onchocerca volvulus is a human pathogenic filarial nematode causing chronic onchocerciasis, a disease characterized by chronic skin and eye lesions. despite attempts to control this infection from many perspectives, it still remains a threat to public health because of adverse effects of available drugs and recent reports of drug resistance. under control of an intact immune system, o. volvulus survives for a long time in the host by employing a variety of strategies including the utility of ant ...201222677600
the chemokine cxcl12 is essential for the clearance of the filaria litomosoides sigmodontis in resistant mice.litomosoides sigmodontis is a cause of filarial infection in rodents. once infective larvae overcome the skin barrier, they enter the lymphatic system and then settle in the pleural cavity, causing soft tissue infection. the outcome of infection depends on the parasite's modulatory ability and also on the immune response of the infected host, which is influenced by its genetic background. the goal of this study was to determine whether host factors such as the chemokine axis cxcl12/cxcr4, which ...201222511975
overcoming species boundaries in peptide identification with bayesian information criterion-driven error-tolerant peptide search (biceps).currently, the reliable identification of peptides and proteins is only feasible when thoroughly annotated sequence databases are available. although sequencing capacities continue to grow, many organisms remain without reliable, fully annotated reference genomes required for proteomic analyses. standard database search algorithms fail to identify peptides that are not exactly contained in a protein database. de novo searches are generally hindered by their restricted reliability, and current er ...201222493179
chronic helminth infection does not exacerbate mycobacterium tuberculosis infection.chronic helminth infections induce a th2 immune shift and establish an immunoregulatory milieu. as both of these responses can suppress th1 immunity, which is necessary for control of mycobacterium tuberculosis (mtb) infection, we hypothesized that chronic helminth infections may exacerbate the course of mtb.201223285308
differential tissular distribution of litomosoides sigmodontis microfilariae between microfilaremic and amicrofilaremic mice following experimental infection.filariases are caused by onchocercid nematodes that are transmitted by arthropod vectors. more than 180 million people are infected worldwide. mass drug administration has been set up in many endemic areas to control the parasite burden. although very successful in limiting microfilarial load, transmission has not been completely interrupted in such areas. a proportion of infected patients with lymphatic filariasis or loiasis are known to be amicrofilaremic, as they do not present microfilariae ...201223193519
deletion of parasite immune modulatory sequences combined with immune activating signals enhances vaccine mediated protection against filarial nematodes.filarial nematodes are tissue-dwelling parasites that can be killed by th2-driven immune effectors, but that have evolved to withstand immune attack and establish chronic infections by suppressing host immunity. as a consequence, the efficacy of a vaccine against filariasis may depend on its capacity to counter parasite-driven immunomodulation.201223301106
characterization of the dmae-modified juvenile excretory-secretory protein juv-p120 of litomosoides sigmodontis.juv-p120 is an excretory-secretory 160 kda glycoprotein of juvenile female litomosoides sigmodontis and exhibits features typical for mucins. 50% of its molecular mass is attributed to posttranslational modifications with the unusual substituent dimethylaminoethanol (dmae). by that juv-p120 corresponds to the surface proteins of the microfilarial sheath, shp3 and shp3a. the secreted protein consists of 697 amino acids, organized in two different domains of repeat elements separated by a stretch ...201121241743
a novel and divergent role of granzyme a and b in resistance to helminth infection.granzyme (gzm) a and b, proteases of nk cells and t killer cells, mediate cell death, but also cleave extracellular matrices, inactivate intracellular pathogens, and induce cytokines. moreover, macrophages, th2 cells, regulatory t cells, mast cells, and b cells can express gzms. we recently reported gzm induction in human filarial infection. in this study, we show that in rodent filarial infection with litomosoides sigmodontis, worm loads were significantly reduced in gzma × b and gzmb knockout ...201121248253
effects of doxycycline on early infections of dirofilaria immitis in dogs.the antifilarial effects of tetracycline drugs were first demonstrated when they were found to be highly effective against l(3) and l(4) of brugia pahangi and litomosoides sigmodontis in rodent models. tetracyclines are also now known to have activity against microfilariae and adult dirofilaria immitis, but assessment of their activity against larval and juvenile heartworms has not been reported previously. this study assessed the effects of doxycycline administered orally at 10mg/kg twice daily ...201121345592
nematode-induced interference with the anti-plasmodium cd8(+) t-cell response can be overcome by optimizing antigen administration.malaria is still responsible for up to 1 million deaths per year worldwide, highlighting the need for protective malaria vaccines. helminth infections that are prevalent in malaria endemic areas can modulate immune responses of the host. here we show that strongyloides ratti, a gut-dwelling nematode that causes transient infections, did not change the efficacy of vaccination against plasmodium berghei. an ongoing infection with litomosoides sigmodontis, a tissue-dwelling filaria that induces chr ...201122161305
Pathogenic nematodes suppress humoral responses to third-party antigens in vivo by IL-10-mediated interference with Th cell function.One third of the human population is infected with helminth parasites. To promote their longevity and to limit pathology, helminths have developed several strategies to suppress the immune response of their host. As this immune suppression also acts on unrelated third-party Ags, a preexisting helminth infection may interfere with vaccination efficacy. In this study, we show that natural infection with Litomosoides sigmodontis suppressed the humoral response to thymus-dependent but not to thymus- ...201121900178
nucleic acid transfection and transgenesis in parasitic nematodes.summarytransgenesis is an essential tool for assessing gene function in any organism, and it is especially crucial for parasitic nematodes given the dwindling armamentarium of effective anthelmintics and the consequent need to validate essential molecular targets for new drugs and vaccines. two of the major routes of gene delivery evaluated to date in parasitic nematodes, bombardment with dna-coated microparticles and intragonadal microinjection of dna constructs, draw upon experience with the f ...201121880161
helminth protection against autoimmune diabetes in nonobese diabetic mice is independent of a type 2 immune shift and requires tgf-β.leading hypotheses to explain helminth-mediated protection against autoimmunity postulate that type 2 or regulatory immune responses induced by helminth infections in the host limit pathogenic th1-driven autoimmune responses. we tested these hypotheses by investigating whether infection with the filarial nematode litomosoides sigmodontis prevents diabetes onset in il-4-deficient nod mice and whether depletion or absence of regulatory t cells, il-10, or tgf-β alters helminth-mediated protection. ...201122174447
ccl17 controls mast cells for the defense against filarial larval entry.filarial parasites have to trespass many barriers to successfully settle within their mammalian host, which is equipped with mechanical borders and complex weaponry of an evolved immune system. however, little is known about mechanisms of early local events in filarial infections. in this study, bone marrow-derived dendritic cells not only upregulated activation markers cd40 and cd80 upon in vitro stimulation with filarial extracts, but also secreted ccl17, a chemokine known to be produced upon ...201121398605
Th2 responses to helminth parasites can be therapeutically enhanced by, but are not dependent upon, GITR-GITR ligand costimulation in vivo.The immune suppression that characterizes human helminth infections can hinder the development of protective immunity or help to reduce pathogenic inflammation. Signaling through the T cell costimulator glucocorticoid-induced TNFR-related protein (GITR) counteracts immune downregulation by augmenting effector T cell responses and abrogating suppression by Foxp3(+) regulatory T cells. Thus, superphysiological Ab-mediated GITR costimulation represents a novel therapy for promoting protective immun ...201121705620
over expression of il-10 by macrophages overcomes resistance to murine filariasis.individuals infected with parasitic helminths are able to tolerate the presence of parasites for considerable time without clinical pathology. immunosuppressive responses induced by the filarial parasite are considered responsible for this long-lasting relationship, inuring to the benefit of both parasite and host. in order to directly link il-10 with parasite survival, we infected mice, in which over expression of il-10 was restricted to macrophages under control of the cd68 promoter (macil-10t ...201121959021
basophils amplify type 2 immune responses, but do not serve a protective role, during chronic infection of mice with the filarial nematode litomosoides sigmodontis.chronic helminth infections induce a type 2 immune response characterized by eosinophilia, high levels of ige, and increased t cell production of type 2 cytokines. because basophils have been shown to be substantial contributors of il-4 in helminth infections, and because basophils are capable of inducing th2 differentiation of cd4(+) t cells and ige isotype switching in b cells, we hypothesized that basophils function to amplify type 2 immune responses in chronic helminth infection. to test thi ...201021057084
mitochondrial genes for heme-dependent respiratory chain complexes are up-regulated after depletion of wolbachia from filarial nematodes.the filarial nematodes brugia malayi, wuchereria bancrofti and onchocerca volvulus cause elephantiasis or dermatitis and blindness resulting in severe morbidity. annually, 1.3 billion people are at risk of infection. targeting the essential wolbachia endobacteria of filarial nematodes with doxycycline has proven to be an effective therapy resulting in a block in embryogenesis, worm development and macrofilaricidal effects. however, doxycycline is contraindicated for a large portion of the at ris ...201020362581
comparing de novo assemblers for 454 transcriptome data.roche 454 pyrosequencing has become a method of choice for generating transcriptome data from non-model organisms. once the tens to hundreds of thousands of short (250-450 base) reads have been produced, it is important to correctly assemble these to estimate the sequence of all the transcripts. most transcriptome assembly projects use only one program for assembling 454 pyrosequencing reads, but there is no evidence that the programs used to date are optimal. we have carried out a systematic co ...201020950480
type 2 immune-inducing helminth vaccination maintains protective efficacy in the setting of repeated parasite exposures.animal studies have demonstrated that helminth vaccines which induce type 2 immune responses can be protective. to date, however, such vaccines have not been tested against repeated parasite challenges. since repeated antigenic challenge of patients with allergic disease results in immunologic tolerance, we hypothesized that a helminth vaccine which induces type 2 immune responses may lose its protective efficacy in the setting of repeated parasite exposures (rpes). to test this hypothesis, we e ...201020035827
antibody isotype analysis of malaria-nematode co-infection: problems and solutions associated with cross-reactivity.antibody isotype responses can be useful as indicators of immune bias during infection. in studies of parasite co-infection however, interpretation of immune bias is complicated by the occurrence of cross-reactive antibodies. to confidently attribute shifts in immune bias to the presence of a co-infecting parasite, we suggest practical approaches to account for antibody cross-reactivity. the potential for cross-reactive antibodies to influence disease outcome is also discussed.201020163714
filaria-induced il-10 suppresses murine cerebral malaria.filarial nematodes achieve long survival in their hosts due to their capacity to modulate immune responses. therefore, immunomodulation by filarial nematodes may alter responses to concomitant infections such as malaria. cerebral malaria (cm), a severe complication of plasmodium falciparum infections, is triggered as a consequence of the immune response developed against malaria parasites. the question arises whether prior infection with helminth parasites is beneficial against cm. in the presen ...201020420933
litomosoides sigmodontis: a simple method to infect mice with l3 larvae obtained from the pleural space of recently infected jirds (meriones unguiculatus).litomosoides sigmodontis is a filarial nematode that is used as a mouse model for human filarial infections. the life cycle of l. sigmodontis comprises rodents as definitive hosts and tropical rat mites as alternate hosts. here, we describe a method of infecting mice with third stage larvae (l3) extracted from the pleural space of recently infected jirds (meriones unguiculatus). this method enables infection of mice with a known number of l3 larvae without the time-consuming dissection of l3 lar ...200919463816
a putative nuclear growth factor-like globular nematode specific protein.expressed sequence tags (ests) are an effective approach for discovery of novel genes. in the current study, approximately 250 ests of the cattle parasitic nematode setaria digitata were examined and a cdna clone identified whose coding sequence could not be functionally annotated by searching over publicly available genome, protein, est and sts databases. here, we report the extensive characterization of this orf (up) and its homologues using a bioinformatic approach. uncharacterized protein (s ...200919759810
filarial infection induces protection against p. berghei liver stages in mice.chronic helminth infections such as filariasis in human hosts can be life long, since parasites are equipped with a repertoire of immune evasion strategies. in many areas where helminths are prevalent, other infections such as malaria are co-endemic. it is still an ongoing debate, how one parasite alters immune responses against another. to dissect the relationships between two different parasites residing in the same host, we established a murine model of co-infection with the filarial nematode ...200919049828
inhibition of type 1 diabetes in filaria-infected non-obese diabetic mice is associated with a t helper type 2 shift and induction of foxp3+ regulatory t cells.we sought to determine whether litomosoides sigmodontis, a filarial infection of rodents, protects against type 1 diabetes in non-obese diabetic (nod) mice. six-week-old nod mice were sham-infected or infected with either l3 larvae, adult male worms, or adult female worms. whereas 82% of uninfected nod mice developed diabetes by 25 weeks of age, no l. sigmodontis-infected mice developed disease. although all mice had evidence of ongoing islet cell inflammation by histology, l. sigmodontis-infect ...200919016910
early recruitment of natural cd4+ foxp3+ treg cells by infective larvae determines the outcome of filarial infection.human helminth infections are synonymous with impaired immune responsiveness indicating suppression of host immunity. using a permissive murine model of filariasis, litomosoides sigmodontis infection of inbred mice, we demonstrate rapid recruitment and increased in vivo proliferation of cd4(+)foxp3(+) treg cells upon exposure to infective l3 larvae. within 7 days post-infection this resulted in an increased percentage of cd4(+)t cells at the infection site expressing foxp3. antibody-mediated dep ...200919089814
of mice, cattle, and humans: the immunology and treatment of river blindness.river blindness is a seriously debilitating disease caused by the filarial parasite onchocerca volvulus, which infects millions in africa as well as in south and central america. research has been hampered by a lack of good animal models, as the parasite can only develop fully in humans and some primates. this review highlights the development of two animal model systems that have allowed significant advances in recent years and hold promise for the future. experimental findings with litomosoide ...200818446236
does litomosoides sigmodontis synthesize dimethylethanolamine from choline?juvenile female litomosoides sigmodontis secrete a protein (juv-p120) highly modified with dimethylethanolamine (dmae). in an attempt to establish the source of this decoration worms were pulsed with [3h]-choline and [3h]-ethanolamine and the radio-isotope labelled products analysed. both isotope labels were successfully taken up by the worms, as demonstrated by labelling of phospholipids with [3h]-choline, being predominantly incorporated into phosphatidylcholine and [3h]-ethanolamine into phos ...200817892618
antifilarial activity of caesalpinia bonducella against experimental filarial infections.lymphatic filariasis is a disabling disease that continues to cripple population in tropical countries. currently available antifilarial drugs are not able to control the disease. therefore, a better antifilarial is urgently required for proper management of the disease. we undertook this study to assess the antifilarial activity of caesalpinia bonducella-seed kernel against rodent filarial parasite in experimental model.200818820361
helminth infection with litomosoides sigmodontis induces regulatory t cells and inhibits allergic sensitization, airway inflammation, and hyperreactivity in a murine asthma model.numerous epidemiological studies have shown an inverse correlation between helminth infections and the manifestation of atopic diseases, yet the immunological mechanisms governing this phenomenon are indistinct. we therefore investigated the effects of infection with the filarial parasite litomosoides sigmodontis on allergen-induced immune reactions and airway disease in a murine model of asthma. infection with l. sigmodontis suppressed all aspects of the asthmatic phenotype: ag-specific ig prod ...200818209076
infection of the intermediate mite host with wolbachia-depleted litomosoides sigmodontis microfilariae: impaired l1 to l3 development and subsequent sex-ratio distortion in adult worms.the rodent filaria litomosoides sigmodontis harbour wolbachia, endosymbionts essential for worm embryogenesis, larval development and adult survival. to study the effect of tetracycline, which depletes wolbachia, on the development of microfilariae (l1s, mf) to l3 in the intermediate host ornithonyssus bacoti, and to observe the development of wolbachia-depleted l3s in mongolian gerbils (meriones unguiculatus); microfilaremic gerbils were treated orally with tetracycline for 6 weeks (primary inf ...200818282572
pleural cellular reaction to the filarial infection litomosoides sigmodontis is determined by the moulting process, the worm alteration, and the host strain.the filarial nematode litomosoides sigmodontis model was used to decipher the complex in vivo relationships between filariae, granulomas and leukocytes in the host's pleural cavity. the study was performed from d5 p.i.: to d47 p.i. in resistant c57bl/6 mice, to d74 p.i. in susceptible balb/c mice, and to d420 p.i. in permissive jirds. we showed that, during the first month, leukocytes only clustered as granulomas around shed cuticles (exuviae) and with eosinophils as the major constituents. in a ...200818295534
litomosoides sigmodontis: vaccine-induced immune responses against wolbachia surface protein can enhance the survival of filarial nematodes during primary infection.wolbachia are bacteria present within the tissues of most filarial nematodes. filarial nematode survival is known to be affected by immune responses generated during filarial nematode infection and immune responses to wolbachia can be found in different species harbouring filarial nematode infections, including humans. using the rodent filarial model litomosoides sigmodontis, we show that pre-exposure to wolbachia surface protein in a th1 context (but not in a th2-context) enhances worm survival ...200817919582
microfilariae of the filarial nematode litomosoides sigmodontis exacerbate the course of lipopolysaccharide-induced sepsis in mice.helminths facilitate their own survival by actively modulating the immune systems of their hosts. we investigated the impacts that different life cycle stages of the rodent filaria litomosoides sigmodontis have on the inflammatory responses of mice injected with sublethal doses of lipopolysaccharide (lps). mice infected with female adult worms from prepatent infections, worms which have not yet started to release microfilariae, developed lower levels of proinflammatory cytokines in the periphera ...200818250172
ctla-4 and cd4+ cd25+ regulatory t cells inhibit protective immunity to filarial parasites in vivo.the t cell coinhibitory receptor ctla-4 has been implicated in the down-regulation of t cell function that is a quintessential feature of chronic human filarial infections. in a laboratory model of filariasis, litomosoides sigmodontis infection of susceptible balb/c mice, we have previously shown that susceptibility is linked both to a cd4+ cd25+ regulatory t (treg) cell response, and to the development of hyporesponsive cd4+ t cells at the infection site, the pleural cavity. we now provide evid ...200717878360
ultrasonography in filaria-infected rodents: detection of adult litomosoides sigmodontis and brugia malayi filariae.to evaluate the usefulness of ultrasonography (usg) in the detection of adult filariae in rodents. wuchereria bancrofti are frequently detected using usg in humans, whereas adult brugia malayi have not been so far.200616930260
differential display of genes expressed in the filarial nematode litomosoides sigmodontis reveals a putative phosphate permease up-regulated after depletion of wolbachia endobacteria.mutualist symbiotic wolbachia endobacteria are found in most filarial nematodes. wolbachia are essential for embryogenesis and for larval development into adults, and thus represent a new target for anti-filarial drug development. tetracycline antibiotics deplete wolbachia in animal model filaria litomosoides sigmodontis and brugia pahangi, as well as in the human parasites brugia malayi, onchocerca volvulus and wuchereria bancrofti. very little is known about the molecular details of the symbio ...200616616613
lack of eosinophil peroxidase or major basic protein impairs defense against murine filarial infection.eosinophils are a hallmark of allergic diseases and helminth infection, yet direct evidence for killing of helminth parasites by their toxic granule products exists only in vitro. we investigated the in vivo roles of the eosinophil granule proteins eosinophil peroxidase (epo) and major basic protein 1 (mbp) during infection with the rodent filaria litomosoides sigmodontis. mice deficient for either epo or mbp on the 129/svj background developed significantly higher worm burdens than wild-type mi ...200616926417
f4/80+ alternatively activated macrophages control cd4+ t cell hyporesponsiveness at sites peripheral to filarial infection.both t cells and apc have been strongly implicated in the immune suppression observed during filarial nematode infections, but their relative roles are poorly understood, particularly in regard to timing and locality of action. using litomosoides sigmodontis infection of susceptible balb/c mice, we have studied the progression of filarial immunosuppression leading to patent infection with blood microfilaremia. patent infection is associated with decreased immune responsiveness in the draining th ...200616709852
rnai mediated silencing of actin expression in adult litomosoides sigmodontis is specific, persistent and results in a phenotype.in this report, the actin gene from the rodent filaria litomosoides sigmodontis was successfully knocked down by rna interference (rnai). by establishing controls for measuring off-target rnai effects we showed that lower concentrations of double stranded rna (dsrna) are more effective than those previously reported. while all tested concentrations reduced ls-act transcription, the concentration that consistently reduced ls-act expression to <10% of the controls was 3.5 microm, a 10-fold lower c ...200616546192
vaccination against filarial nematodes with irradiated larvae provides long-term protection against the third larval stage but not against subsequent life cycle stages.sustainable control of human filariasis would benefit enormously from the development of an effective vaccine. the ability to vaccinate experimental animals, with reductions in worm burden of over 70%, suggests this aim is possible. however, in experimental vaccinations the challenge is usually administered 2 weeks after the immunisation phase and thus the protection obtained is likely to be biased by persisting inflammation. using the murine model litomosoides sigmodontis, we increased the time ...200616765354
co-infected c57bl/6 mice mount appropriately polarized and compartmentalized cytokine responses to litomosoides sigmodontis and leishmania major but disease progression is altered.this study examines the capacity of the mammalian host to fully compartmentalize the response to infection with type 1 vs. type 2 inducing organisms that infect different sites in the body. for this purpose, c57bl/6 mice were infected with the rodent filarial nematode litomosoides sigmodontis followed by footpad infection with the protozoan parasite leishmania major. in this host, nematode infection is established in the thoracic cavity but no microfilariae circulate in the bloodstream. we utili ...200516149989
the subcutaneous movements of filarial infective larvae are impaired in vaccinated hosts in comparison to primary infected hosts.our aim in this study was to observe the movements of filarial infective larvae following inoculation into the mammalian host and to assess the effect of vaccination on larval migration, in situ. here we present recordings of larvae progressing through the subcutaneous tissues and inguinal lymph node of primary infected or vaccinated mice. we used the filaria litomosoides sigmodontis in balb/c mice that were necropsied 6 hours after the challenge inoculation of 200 larvae. subcutaneous tissue se ...200515916708
blood-feeding in the young adult filarial worms litomosoides sigmodontis.in this study with the filarial model litomosoides sigmodontis, we demonstrate that the worms ingest host red blood cells at a precise moment of their life-cycle, immediately after the fourth moult. the red blood cells (rbc) were identified microscopically in live worms immobilized in pbs at 4 degrees c, and their density assessed. two hosts were used: mongolian gerbils, where microfilaraemia is high, and susceptible balb/c mice with lower microfilaraemia. gerbils were studied at 12 time-points, ...200515830816
quantitative appraisal of murine filariasis confirms host strain differences but reveals that balb/c females are more susceptible than males to litomosoides sigmodontis.litomosoides sigmodontis, a rodent filarial nematode, can infect inbred laboratory mice, with full development to patency in the balb/c strain. strains such as c57bl/6 are considered resistant, because although filarial development can occur, circulating microfilariae are never detected. this model system has, for the first time, allowed the power of murine immunology to be applied to fundamental questions regarding susceptibility to filarial nematode infection. as this is a relatively new model ...200515820154
removal of regulatory t cell activity reverses hyporesponsiveness and leads to filarial parasite clearance in vivo.human filarial parasites cause chronic infection associated with long-term down-regulation of the host's immune response. we show here that cd4+ t cell regulation is the main determinant of parasite survival. in a laboratory model of infection, using litomosoides sigmodontis in balb/c mice, parasites establish for >60 days in the thoracic cavity. during infection, cd4+ t cells at this site express increasing levels of cd25, ctla-4, and glucocorticoid-induced tnf receptor family-related gene (git ...200515814720
chitinase and fizz family members are a generalized feature of nematode infection with selective upregulation of ym1 and fizz1 by antigen-presenting cells.ym1 and fizz1 are secreted proteins that have been identified in a variety of th2-mediated inflammatory settings. we originally found ym1 and fizz1 as highly expressed macrophage genes in a brugia malayi infection model. here, we show that their expression is a generalized feature of nematode infection and that they are induced at the site of infection with both the tissue nematode litomosoides sigmodontis and the gastrointestinal nematode nippostrongylus brasiliensis. at the sites of infection ...200515618176
increased early local immune responses and altered worm development in high-dose infections of mice susceptible to the filaria litomosoides sigmodontis.the relationship between the number of larvae inoculated and filarial infection outcome is an important fundamental and epidemiological issue. our study was carried out with balb/c mice infected with the filaria litomosoides sigmodontis. for the first time, an immunological analysis of infection with various doses was studied in parallel with parasitological data. mice were inoculated with 200, 60 or 25 infective larvae (third stage larvae, l3), and monitored over 80 days. at 60 h post-inoculati ...200515338299
most of the response elicited against wolbachia surface protein in filarial nematode infection is due to the infective larval stage.immune responses to the intracellular wolbachia bacteria of filarial nematodes are thought to contribute to the pathologic process of filarial infection. here, we compare antibody responses of subjects living in an area where lymphatic filariasis is endemic with antibody responses elicited in a murine model of filarial infection, to provide evidence that the infective larval stage (l3), not adult nematodes, are the primary inducer of responses against wolbachia. in human subjects, antibody respo ...200414702162
the antifilarial activity of a marine red alga, botryocladia leptopoda, against experimental infections with animal and human filariae.the antifilarial activity of the marine red alga botryocladia leptopoda against rodent and human lymphatic filarial parasites is described. the animal filarial species included litomosoides sigmodontis and acanthocheilonema viteae maintained in cotton rats and mastomys coucha, respectively, while a subperiodic strain of the human lymphatic filarial parasite brugia malayi was maintained in m. coucha. the crude extract and its hexane fraction brought about a marked reduction in the peripheral micr ...200415243801
interleukin-10 (il-10) counterregulates il-4-dependent effector mechanisms in murine filariasis.interleukin-10 (il-10) was at first described as a th2-associated cytokine, although more recent reports have shown that immunosuppression applies to both th1 and th2 cell responses, e.g., when produced by t regulatory cells. this concept when applied to human filariasis would argue that high parasite loads are associated with il-10, while bona fide th2 responses, mediated by il-4, il-5, and il-13, are associated with parasite containment. to prove this relationship in a causal manner, we invest ...200415501755
malaria-filaria coinfection in mice makes malarial disease more severe unless filarial infection achieves patency.coinfections are common in natural populations, and the literature suggests that helminth coinfection readily affects how the immune system manages malaria. for example, type 1-dependent control of malaria parasitemia might be impaired by the type 2 milieu of preexisting helminth infection. alternatively, immunomodulatory effects of helminths might affect the likelihood of malarial immunopathology. using rodent models of lymphatic filariasis (litomosoides sigmodontis) and noncerebral malaria (cl ...200415633101
involvement of toll-like receptor 4 in the embryogenesis of the rodent filaria litomosoides sigmodontis.to examine the role that lipopolysaccharide (lps)-like molecules from the filarial intracellular endobacteria wolbachia might play in the development of filarial infections, a natural infection in the lps-nonresponsive c3h/hej mouse strain was compared to that of the lps-responsive c3h/hen mouse strain. c3h/hen mice have been shown to be susceptible to the rodent filarial nematode litomosoides sigmodontis, with the development of adult worms including females containing mature microfilariae (fir ...200312592564
antibiotic therapy in murine filariasis (litomosoides sigmodontis): comparative effects of doxycycline and rifampicin on wolbachia and filarial viability.the symbiosis of filarial nematodes and rickettsial wolbachia endobacteria has been exploited as a target for antibiotic therapy of filariasis. depletion of wolbachia after tetracycline treatment results in filarial sterility because of interruption of embryogenesis and inhibits larval development and adult worm viability. the aim of this study was to investigate if antibiotic intervention of balb/c mice infected with the rodent filaria litomosoides sigmodontis with rifampicin or the combination ...200312753632
evidence against wolbachia symbiosis in loa loa.background: the majority of filarial nematode species are host to wolbachia bacterial endosymbionts, although a few including acanthocheilonema viteae, onchocerca flexuosa and setaria equina have been shown to be free of infection. comparisons of species with and without symbionts can provide important information on the role of wolbachia symbiosis in the biology of the nematode hosts and the contribution of the bacteria to the development of disease. previous studies by electron microscopy and ...200312816546
resistance and susceptibility to filarial infection with litomosoides sigmodontis are associated with early differences in parasite development and in localized immune reactions.in order to understand natural resistance to filariasis, we compared litomosoides sigmodontis primary infection of c57bl/6 mice, which eliminate the worms before patency, and balb/c mice, in which worms complete their development and produce microfilariae. our analysis over the first month of infection monitoredmigration of the infective larvae from the lymph nodes to the pleural cavity, where the worms settle. although immune responses from the mouse strains differed from the outset, the durati ...200314638768
trans-species transfer of wolbachia: microinjection of wolbachia from litomosoides sigmodontis into acanthocheilonema viteae.intracellular bacteria of the genus wolbachia are found in most filarial nematodes, but are lacking in some species like acanthocheilonema viteae. due to their symbiotic nature and their role in the pathology of filarial infections they are considered to be potential targets for intervention against filarial infections in man. infection of a. viteae (a species which does not naturally carry wolbachia) with wolbachia bacteria could allow comparative studies on the effect of the endobacterium on t ...200312866789
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