RESUMEN
The zoonotic parasite Cryptosporidium parvum is a global cause of gastrointestinal disease in humans and ruminants. Sequence analysis of the highly polymorphic gp60 gene enabled the classification of C. parvum isolates into multiple groups (e.g., IIa, IIc, Id) and a large number of subtypes. In Europe, subtype IIaA15G2R1 is largely predominant and has been associated with many water- and food-borne outbreaks. In this study, we generated new whole-genome sequence (WGS) data from 123 human- and ruminant-derived isolates collected in 13 European countries and included other available WGS data from Europe, Egypt, China, and the United States (n = 72) in the largest comparative genomics study to date. We applied rigorous filters to exclude mixed infections and analyzed a data set from 141 isolates from the zoonotic groups IIa (n = 119) and IId (n = 22). Based on 28,047 high-quality, biallelic genomic SNPs, we identified three distinct and strongly supported populations: Isolates from China (IId) and Egypt (IIa and IId) formed population 1; a minority of European isolates (IIa and IId) formed population 2; and the majority of European (IIa, including all IIaA15G2R1 isolates) and all isolates from the United States (IIa) clustered in population 3. Based on analyses of the population structure, population genetics, and recombination, we show that population 3 has recently emerged and expanded throughout Europe to then, possibly from the United Kingdom, reach the United States, where it also expanded. The reason(s) for the successful spread of population 3 remain elusive, although genes under selective pressure uniquely in this population were identified.
Asunto(s)
Criptosporidiosis , Cryptosporidium parvum , Brotes de Enfermedades , Cryptosporidium parvum/genética , Estados Unidos/epidemiología , Europa (Continente)/epidemiología , Humanos , Criptosporidiosis/parasitología , Criptosporidiosis/epidemiología , Animales , Genómica/métodos , Polimorfismo de Nucleótido Simple , Filogenia , Secuenciación Completa del Genoma/métodos , Genoma de Protozoos , China/epidemiología , Egipto/epidemiologíaRESUMEN
Cryptosporidium spp. remain a major cause of waterborne diarrhea and illness in developing countries and represent a significant burden to farmers worldwide. Cryptosporidium parvum virus 1 (CSpV1), of the genus Cryspovirus, was first reported to be present in the cytoplasm of C. parvum in 1997. Full-length genome sequences have been obtained from C. parvum from Iowa (Iowa), Kansas (KSU) and China. We aimed at characterizing the genome of CSpV1 from France and used sequence analysis from Cryptosporidium isolates to explore whether CSpV1 genome diversity varies over time, with geographical sampling location, C. parvum genetic diversity, or ruminant host species. A total of 123 fecal samples of cattle, sheep and goats were collected from 17 different French departments (57 diseased animal fecal samples and 66 healthy animal fecal samples). Subtyping analysis of the C. parvum isolates revealed the presence of two zoonotic subtype families IIa and IId. Sequence analysis of CSpV1 revealed that all CSpV1 from France, regardless of the subtype of C. parvum (IIaA15G2R1, IIaA17G2R1 and IIdA18G1R1) are more closely related to CSpV1 from Turkey, and cluster on a distinct branch from CSpV1 collected from C. parvum subtype IIaA15G2R1 from Asia and North America. We also found that samples collected on a given year or successive years in a given location are more likely to host the same subtype of C. parvum and the same CSpV1 strain. Yet, there is no distinct clustering of CSpV1 per French department or ruminants, probably due to trade, and transmission of C. parvum among host species. Our results point towards (i) a close association between CSpV1 movement and C. parvum movement, (ii) recent migrations of C. parvum among distantly located departments and (iii) incidental transmission of C. parvum between ruminants. All together, these results provide insightful information regarding CSpV1 evolution and suggest the virus might be used as an epidemiological tracer for C. parvum. Future studies need to investigate CSpV1's role in C. parvum virulence and on subtype ability to infect different species.
Asunto(s)
Enfermedades de los Bovinos , Criptosporidiosis , Cryptosporidium parvum , Cryptosporidium , Enfermedades de las Cabras , Enfermedades de las Ovejas , Ovinos , Animales , Bovinos , Cabras , Cryptosporidium parvum/genética , Criptosporidiosis/epidemiología , Francia/epidemiología , Enfermedades de los Bovinos/epidemiología , Enfermedades de las Cabras/epidemiología , Enfermedades de las Ovejas/epidemiologíaRESUMEN
Centuries of scientific breakthroughs have brought us closer to understanding and managing the spread of parasitic diseases. Despite ongoing technological advancements in the detection, treatment, and control of parasitic illnesses, their effects on animal and human health remain a major concern worldwide. Aptamers are single-stranded oligonucleotides whose unique three-dimensional structures enable them to interact with high specificity and affinity to a wide range of targets. In recent decades, aptamers have emerged as attractive alternatives to antibodies as therapeutic and diagnostic agents. Due to their superior stability, reusability, and modifiability, aptamers have proven to be effective bioreceptors for the detection of toxins, contaminants, biomarkers, whole cells, pathogens, and others. As such, they have been integrated into a variety of electrochemical, fluorescence, and optical biosensors to effectively detect whole parasites and their proteins. This review offers a summary of the various types of parasite-specific aptamer-based biosensors, their general mechanisms and their performance.
Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Parásitos , Animales , Humanos , Parásitos/metabolismo , Aptámeros de Nucleótidos/química , Biomarcadores , Anticuerpos , Técnicas Biosensibles/métodosRESUMEN
Aptamers are small nucleic acids that fold in a three-dimensional conformation allowing them to bind specifically to a target. This target can be an organic molecule, free or carried in cells or tissues, or inorganic components, such as metal ions. Analogous to monoclonal antibodies, aptamers however have certain advantages over the latter: e.g., high specificity for their target, no to low immunogenicity and easy in vitro selection. Since their discovery more than 30 years ago, aptamers have led to various applications, although mainly restricted to basic research. This work reviews the applications of aptamers in veterinary science to date. First, we present aptamers, how they are selected and their properties, then we give examples of applications in food and environmental safety, as well as in diagnosis and medical treatment in the field of veterinary medicine. Because examples of applications in veterinary medicine are scarce, we explore the potential avenues for future applications based on discoveries made in human medicine. Aptamers may offer new possibilities for veterinarians to diagnose certain diseases-particularly infectious diseases-more rapidly or "at the patient's bedside". All the examples highlight the growing interest in aptamers and the premises of a potential market. Aptamers may benefit animals as well as their owners, breeders and even public health in a "One Health" approach.
Asunto(s)
Enfermedades de los Animales/diagnóstico , Aptámeros de Nucleótidos/análisis , Inocuidad de los Alimentos/métodos , Ganado , Aves de Corral , Medicina Veterinaria/métodos , AnimalesRESUMEN
The foodborne zoonotic nematode Trichinella spp. can cause human trichinellosis when raw or undercooked contaminated meat is ingested. To date, twelve Trichinella species/genotypes have been described. According to EU regulation any Trichinella larvae detected during mandatory routine examinations need to be identified at a species level by a competent laboratory. Currently, Trichinella species identification is performed using molecular biology tools such as multiplex PCR, PCR-sequencing or PCR-RFLP. These techniques require high level of skills for good interpretation of the results. Due to its rapidness and ease of use a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) protocol was previously developed for the identification of Trichinella species. Using this method, spectra from different Trichinella species and strains were acquired allowing to generate new Main Spectra (MSP). Finally a new MSP database from Trichinella spp. Samples of different countries (France, Germany and Poland), including field samples, was generated. Comparing the different main spectra, Trichinella worms were identified at the species level and differences in the genetic diversities within the different species are discussed. In conclusion, using the previously described method on field samples is a reliable, rapid, easy-to-use and cheap tool for Trichinella species identification. The new Trichinella database could be incremented with new samples. It constitutes a tool, which could be used as an alternative method to replace the actual molecular methods for Trichinella species identification.
Asunto(s)
Enfermedades Transmitidas por los Alimentos/veterinaria , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/veterinaria , Trichinella/aislamiento & purificación , Triquinelosis/veterinaria , Animales , Enfermedades Transmitidas por los Alimentos/parasitología , Francia , Alemania , Polonia , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Trichinella/clasificación , Triquinelosis/parasitologíaRESUMEN
To ensure that meat from livestock and game is safe for human consumption, European legislation lays down rules for mandatory testing. Helminth larvae are a category of zoonotic foodborne pathogens that can contaminate meat. Among helminths, the only zoonotic nematode regulated in Europe regarding meat inspection is Trichinella spp.. It is precisely during Trichinella testing that other potentially zoonotic larvae can be found. Due to current lack of tools, their identification is often very complicated. Nematode larvae other than Trichinella, recovered from artificial digestions of pig and wild boar muscles from France and Germany, were subjected to a newly developed two-step identification scheme, which includes both morphological examination and molecular assays. The first step is a general orientation towards a broad taxonomic group; the second step consists of targeted identification based on the results of first step. Different parasites were identified, some of which were not zoonotic such as Metastrongylus spp. and Angiostrongylus vasorum, but others are known to be zoonotic such as Toxocara cati, Ascaris suum, and Uncinaria stenocephala. The strategy is efficient for the identification of nematode larvae recovered from muscles but could also be applied for larvae from other sources.
Asunto(s)
Ancylostomatoidea/aislamiento & purificación , Angiostrongylus/aislamiento & purificación , Enfermedades Transmitidas por los Alimentos/parasitología , Carne/parasitología , Metastrongyloidea/aislamiento & purificación , Enfermedades de los Porcinos/parasitología , Trichinella/aislamiento & purificación , Ancylostomatoidea/genética , Angiostrongylus/clasificación , Angiostrongylus/genética , Animales , Ascaris suum/genética , Ascaris suum/aislamiento & purificación , Digestión , Francia , Alemania , Humanos , Larva , Metastrongyloidea/clasificación , Metastrongyloidea/genética , Músculos/parasitología , Reacción en Cadena de la Polimerasa , Sus scrofa/parasitología , Porcinos/parasitología , Toxocara/clasificación , Toxocara/genética , Toxocara/aislamiento & purificación , Trichinella/clasificación , Trichinella/genética , Triquinelosis/parasitología , Triquinelosis/prevención & controlRESUMEN
Trichinellosis is a rare parasitic zoonosis in the European Union. Meat from backyard pigs was the common source for a trichinellosis outbreak caused by Trichinella spiralis, which occurred in France and Serbia in the beginning of 2017. An epidemiological study was conducted in France and Serbia to determine the extent of the outbreak, to identify its source and to implement control measures. Three cases were exposed in Serbia and brought back to France pork delicatessen which they shared with relatives and friends. Around 47 individuals were exposed to the parasitised meat in France and Serbia and 20 cases of trichinellosis were reported (nine in France and 11 in Serbia). Nine of them were female. The diagnosis was delayed, in part because the parasitosis was not known by most physicians, which led to complications in the French cases such as facial paralysis and pulmonary embolism. Health alerts and survey networks are indispensable at a European level to control the disease.
Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Carne de Cerdo/microbiología , Enfermedades de los Porcinos/microbiología , Trichinella spiralis/aislamiento & purificación , Triquinelosis/epidemiología , Adolescente , Adulto , Animales , Animales Salvajes , Niño , Trazado de Contacto , Ensayo de Inmunoadsorción Enzimática , Femenino , Francia/epidemiología , Humanos , Masculino , Productos de la Carne/microbiología , Persona de Mediana Edad , Serbia/epidemiología , Sus scrofa , Porcinos , Enfermedades de los Porcinos/epidemiología , Triquinelosis/diagnóstico , Triquinelosis/prevención & control , Adulto Joven , Zoonosis/epidemiologíaRESUMEN
Haemosporidia parasites have mostly and abundantly been described using mitochondrial genes, and in particular cytochrome b (cytb). Failure to amplify the mitochondrial cytb gene of Nycteria parasites isolated from Nycteridae bats has been recently reported. Bats are hosts to a diverse and profuse array of Haemosporidia parasites that remain largely unstudied. There is a need to obtain more molecular data from chiropteran parasites. Such data would help to better understand the evolutionary history of Haemosporidia, which notably include the Plasmodium parasites, malaria's agents. We use next-generation sequencing to obtain the complete mitochondrial genome of Nycteria parasites from African Nycteris grandis (Nycteridae) and Rhinolophus alcyone (Rhinolophidae) and Asian Megaderma spasma (Megadermatidae). We report four complete mitochondrial genomes, including two rearranged mitochondrial genomes within Haemosporidia. Our results open outlooks into potentially undiscovered Haemosporidian diversity.
Asunto(s)
Quirópteros/parasitología , Genoma Mitocondrial , Genoma de Protozoos , Haemosporida/genética , Proteínas Mitocondriales/genética , Proteínas Protozoarias/genética , Animales , Cambodia , República Democrática del Congo , Haemosporida/clasificación , Secuenciación de Nucleótidos de Alto Rendimiento , Mitocondrias/genética , FilogeniaRESUMEN
Here, we report new insights on the erythrocytic murine parasite Anthemosoma garnhami, which was first described from Ethiopia in 1969. Its classification has been debated for years, as this parasite presents some intermediate characters between the Haemosporidia and the Piroplasmida. Based on electron-microscopy, immunological, biochemical and drug sensitivity studies, it was finally assigned to the piroplasms, in the family Anthemosomatidae. In 1985, Anthemosoma sp. was reported from Namibia, and since then, no investigation has involved this parasite. We re-examined the original material, illustrate the blood stages with a set of coloured microphotographs and performed a morphometric analysis. As no type material was designated at the time of the original description, we designate syntypes. This study provides also the first molecular data on A. garnhami with the amplification and sequencing of two genes: the nuclear 18S small subunit ribosomal RNA and the mitochondrial cytochrome c oxydase subunit I. The phylogenetic analyses of both genes confirm that A. garnhami belongs to the Piroplasmida and appears on its own new branch distinct from both Babesids and Theilerids. This result supports the placement of the genus Anthemosoma in its own family but also invalidates the order Anthemosomida. Being paraphyletic with Babesia, the conundrum about the systematics of the piroplasms is discussed as well as the records, the hosts and the possible vectors of Anthemosoma spp.
Asunto(s)
Piroplasmida/clasificación , Piroplasmida/genética , Animales , Babesia/clasificación , Ciclooxigenasa 1/genética , Etiopía , Ratones , Namibia , Filogenia , ARN Ribosómico 18S/genéticaRESUMEN
Toxocara canis and Toxocara cati are globally distributed, zoonotic roundworm parasites. Human infection can have serious clinical consequences including blindness and brain disorders. In addition to ingesting environmental eggs, humans can become infected by eating infective larvae in raw or undercooked meat products. To date, no studies have assessed the prevalence of Toxocara spp. larvae in meat from animals consumed as food in the UK or assessed tissue exudates for the presence of anti-Toxocara antibodies. This study aimed to assess the potential risk to consumers eating meat products from animals infected with Toxocara spp. Tissue samples were obtained from 155 different food producing animals in the south, southwest and east of England, UK. Tissue samples (n = 226), either muscle or liver, were processed by artificial digestion followed by microscopic sediment evaluation for Toxocara spp. larvae, and tissue exudate samples (n = 141) were tested for the presence of anti-Toxocara antibodies using a commercial ELISA kit. A logistic regression model was used to compare anti-Toxocara antibody prevalence by host species, tissue type and source. While no larvae were found by microscopic examination after tissue digestion, the overall prevalence of anti-Toxocara antibodies in tissue exudates was 27.7%. By species, 35.3% of cattle (n = 34), 15.0% of sheep (n = 60), 54.6% of goats (n = 11) and 61.1% of pigs (n = 18) had anti-Toxocara antibodies. Logistic regression analysis found pigs were more likely to be positive for anti-Toxocara antibodies (odds ration (OR) = 2.89, P = 0.0786) compared with the other species sampled but only at a 10% significance level. The high prevalence of anti-Toxocara antibodies in tissue exudates suggests that exposure of food animals to this parasite is common in England. Tissue exudate serology on meat products within the human food chain could be applied in support of food safety and to identify practices that increase risks of foodborne transmission of zoonotic toxocariasis.
Asunto(s)
Anticuerpos Antihelmínticos , Toxocara , Toxocariasis , Animales , Toxocariasis/epidemiología , Toxocariasis/parasitología , Toxocara/inmunología , Toxocara/aislamiento & purificación , Anticuerpos Antihelmínticos/sangre , Anticuerpos Antihelmínticos/análisis , Ovinos , Porcinos , Bovinos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Inglaterra/epidemiología , Carne/parasitología , Hígado/parasitología , Cabras , Exudados y Transudados/parasitología , Enfermedades de los Porcinos/parasitología , Humanos , Músculos/parasitología , Enfermedades de las Ovejas/parasitología , Enfermedades de las Ovejas/epidemiología , Parasitología de AlimentosRESUMEN
African swine fever virus represents a significant reemerging threat to livestock populations, as its incidence and geographic distribution have surged over the past decade in Europe, Asia, and Caribbean, resulting in substantial socio-economic burdens and adverse effects on animal health and welfare. In a previous report, we described the protective properties of our newly thermo-attenuated strain (ASFV-989) in pigs against an experimental infection of its parental Georgia 2007/1 virulent strain. In this new study, our objective was to characterize the molecular mechanisms underlying the attenuation of ASFV-989. We first compared the activation of type I interferon pathway in response to ASFV-989 and Georgia 2007/1 infections, employing both in vivo and in vitro models. Expression of IFN-α was significantly increased in porcine alveolar macrophages infected with ASFV-989 while pigs infected with Georgia 2007/1 showed higher IFN-α than those infected by ASFV-989. We also used a medium-throughput transcriptomic approach to study the expression of viral genes by both strains, and identified several patterns of gene expression. Subsequently, we investigated whether proteins encoded by the eight genes deleted in ASFV-989 contribute to the modulation of the type I interferon signaling pathway. Using different strategies, we showed that MGF505-4R interfered with the induction of IFN-α/ß pathway, likely through interaction with TRAF3. Altogether, our data reveal key differences between ASFV-989 and Georgia 2007/1 in their ability to control IFN-α/ß signaling and provide molecular mechanisms underlying the role of MGF505-4R as a virulence factor.
Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Interferón Tipo I , Porcinos , Animales , Virulencia , MacrófagosRESUMEN
The physiological significance of metabotropic acetylcholine receptors in parasitic nematodes remains largely unexplored. Here, three different Trichinella spiralis G protein-coupled acetylcholine receptors (TsGAR-1, -2, and -3) were identified in the genome of T. spiralis. The phylogenetic analyses showed that TsGAR-1 and -2 receptors belong to a distinct clade specific to invertebrates, while TsGAR-3 is closest to the cluster of mammalian-type muscarinic acetylcholine receptors (mAChR). The mRNA of TsGAR-1, -2, and -3 was detected in muscle larvae, newborn larvae, and adults. The functional aequorin-based assay in Chinese hamster ovary cells revealed that all three types of T. spiralis GARs trigger the Gq/11 pathway upon activation of the receptor with the acetylcholine ligand. TsGAR-1 and TsGAR-2 showed atypical affinity with classical muscarinic agonists, while TsGAR-3 was sensitive to all muscarinic agonists tested. High concentrations of propiverine antagonist blocked the activities of all three TsGARs, while atropine and scopolamine antagonists effectively inhibited only TsGAR-3. Our data indicate that the distinct pharmacological profile of TsGAR-1 and -2 receptors, as well as the phylogenetic distance between them and their mammalian orthologs, place them as attractive targets for the development of selective anthelmintic drugs interfering with nematodes' cholinergic system.
Asunto(s)
Acetilcolina , Trichinella spiralis , Animales , Cricetinae , Recién Nacido , Humanos , Acetilcolina/farmacología , Agonistas Muscarínicos/farmacología , Trichinella spiralis/genética , Células CHO , Filogenia , Cricetulus , Receptores Acoplados a Proteínas G , Receptores Colinérgicos/genética , Proteínas de Unión al GTPRESUMEN
Trichinellosis caused by Trichinella spiralis is a serious zoonosis with a worldwide distribution. Lentinan (LNT) is known to modulate the intestinal environment with noted health benefits, yet the effect of LNT against intestinal helminth is unknown. In our study, we first observed that LNT could trigger worm expulsion by promoting mucus layer functions through alteration of gut microbiota. LNT restored the abundance of Bacteroidetes and Proteobacteria altered by T. spiralis infection to the control group level. Interestingly, LNT triggered the production of butyrate. Then, we determined the deworming capacity of probiotics (butyrate-producing bacteria) in mice. Collectively, these findings indicated that LNT could modulate intestinal dysbiosis by T. spiralis, drive the expulsion of intestinal helminth and provided an easily implementable strategy to improve the host defence against T. spiralis infection.
Asunto(s)
Trichinella spiralis , Triquinelosis , Animales , Bacterias , Butiratos , Helmintiasis , Parasitosis Intestinales , Lentinano , RatonesRESUMEN
Parasites have developed many strategies to ensure their development, multiplication, and dissemination, including the use of reservoir hosts that are often nondomesticated species. Despite drastic reductions in their populations, wild birds remain widespread worldwide and could constitute some of these reservoirs. We focused on the identification of wild bird species harboring parasite stages in their muscles. Breast muscles of 327 birds of 27 different species were collected at three different sites in France. After artificial digestion, isolated nematode larvae were identified by PCR sequencing or restriction fragment length polymorphism (PCR-RFLP). Toxocara cati was identified mainly in birds of prey. The presence of anti-Toxoplasma antibodies was investigated by modified agglutination test on muscle fluids. Anti-Toxoplasma antibodies were detected in 65 out of 166 samples from various bird species. Avifauna, particularly birds of prey, could help on the surveillance of parasite circulation and play a role as sentinel species.
Asunto(s)
Enfermedades de las Aves , Rapaces , Toxoplasma , Toxoplasmosis Animal , Animales , Animales Salvajes/parasitología , Anticuerpos Antiprotozoarios , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/parasitología , Aves/parasitología , Toxocara , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/parasitologíaRESUMEN
BACKGROUND: More than a hundred species of mammals, birds, and reptiles are infected by nematodes of the Trichinella genus worldwide. Although, Trichinella spp. are widely distributed in neighboring countries including Georgia, Azerbaijan, Turkey and Iran, no study was conducted in Armenia since 1980's. METHODS: In 2017-2018, five muscle samples belonging to Armenian lynx, otter, wild boar, fox and wolf were tested for Trichinella spp. and recovered larvae were identified by multiplex PCR technique. RESULTS: Twenty-six larvae/gram and one larva/gram were found in lynx and fox samples respectively. They were identified as T. britovi. CONCLUSION: So far only two species were identified in Armenia, T. spiralis and T. pseudospiralis, and this is the first time that T. britovi is reported in Armenia.
RESUMEN
In order to identify Trichinella at the species level, the commonly used test is a multiplex PCR, allowing the discrimination of nine out of the twelve taxa described so far. This test is based on five primer pairs amplifying fragments of the large subunit rDNA. Each taxon produces one or two bands of different sizes, resulting in a specific band pattern. By multiplex PCR, Trichinella murrelli shows two bands of 127 bp and 316 bp. However, a third band of 256 bp can occur. This band can lead to misidentification, since it is similar to the 253 bp band displayed by Trichinella britovi. BLAST analysis confirmed that the 256 bp band is from T. murrelli. The aim of this short note is to inform analysts that T. murrelli larvae may display either two- or three-band patterns.
TITLE: Identification moléculaire des espèces de Trichinella par PCR multiplex : nouvel éclairage pour Trichinella murrelli. ABSTRACT: Afin d'identifier les Trichinella au niveau de l'espèce, le test couramment utilisé est une PCR multiplex, permettant la discrimination de neuf des douze taxons décrits jusqu'à présent. Ce test est basé sur cinq paires d'amorces amplifiant des fragments de la grande sous-unité l'ADN ribosomal. Chaque taxon produit une ou deux bandes de tailles différentes, résultant en un patron de bandes spécifique. Par PCR multiplex, Trichinella murrelli présente deux bandes de 127 pb et 316 pb. Cependant, une troisième bande de 256 pb peut s'observer. Cette bande peut être la cause d'une erreur d'identification, car elle est similaire à la bande de 253 pb affichée par Trichinella britovi. L'analyse BLAST a confirmé que la bande à 256 pb provient de T. murrelli. Le but de cette note est d'informer les analystes que les larves de T. murrelli peuvent présenter des patrons à deux ou trois bandes.
Asunto(s)
ADN de Helmintos/aislamiento & purificación , Reacción en Cadena de la Polimerasa Multiplex , Trichinella/genética , Animales , ADN de Helmintos/química , ADN de Helmintos/genética , Electroforesis en Gel de Agar , Femenino , Larva/clasificación , Larva/genética , Ratones , Alineación de Secuencia , Trichinella/clasificación , Trichinella/aislamiento & purificaciónRESUMEN
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 around day 30. Little is known of the early phase of the parasite life cycle, after the L3 is inoculated in the dermis by the vector and enters the afferent lymphatic vessels and before the moulting processes in the pleural cavity. Here we reveal a pulmonary phase associated with lung damage characterized by haemorrhages and granulomas suggesting L3 reach the lung via pulmonary capillaries and damage the endothelium and parenchyma by crossing them to enter the pleural cavity. This study also provides evidence for a transient inflammation in the lung characterized by a very early recruitment of neutrophils associated with high expression levels of S100A8 and S100A9 proteins.
Asunto(s)
Calgranulina B/análisis , Filariasis/patología , Filarioidea/crecimiento & desarrollo , Filarioidea/inmunología , Pulmón/patología , Neutrófilos/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , Filariasis/parasitología , Humanos , Pulmón/parasitología , Ratones Endogámicos BALB CRESUMEN
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 profound blood neutropenia (Cxcr4(+/1013)). We provided manifold evidence emphasizing the major role of neutrophils in the control of the early stages of infection occurring in the skin. Firstly, we uncovered that the filarial parasitic success was dramatically decreased in Cxcr4(+/1013) mice upon subcutaneous delivery of the infective stages of filariae (infective larvae, L3). This protection was linked to a larger number of neutrophils constitutively present in the skin of the mutant mice herein characterized as compared to wild type (wt) mice. Indeed, the parasitic success in Cxcr4(+/1013) mice was normalized either upon depleting neutrophils, including the pool in the skin, or bypassing the skin via the intravenous infection of L3. Second, extending these observations to wt mice we found that subcutaneous delivery of L3 elicited an increase of neutrophils in the skin. Finally, living L3 larvae were able to promote in both wt and mutant mice, an oxidative burst response and the release of neutrophil extracellular traps (NET). This response of neutrophils, which is adapted to the large size of the L3 infective stages, likely directly contributes to the anti-parasitic strategies implemented by the host. Collectively, our results are demonstrating the contribution of neutrophils in early anti-filarial host responses through their capacity to undertake different anti-filarial strategies such as oxidative burst, degranulation and NETosis.
Asunto(s)
Filariasis/patología , Filariasis/parasitología , Filarioidea/inmunología , Inmunidad Innata , Neutrófilos/inmunología , Piel/patología , Piel/parasitología , Animales , Modelos Animales de Enfermedad , Filarioidea/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/inmunología , Procedimientos de Reducción del Leucocitos , Ratones , Receptores CXCR4/genética , Receptores CXCR4/metabolismoRESUMEN
Life cycles and molecular data for terrestrial haemogregarines are reviewed in this article. Collection material was re-examined: Hepatozoon argantis Garnham, 1954 in Argas brumpti was reassigned to Hemolivia as Hemolivia argantis (Garnham, 1954) n. comb.; parasite DNA was extracted from a tick crush on smear of an archived slide of Hemolivia stellata in Amblyomma rotondatum, then the 18S ssrRNA gene was amplified by PCR. A systematic revision of the group is proposed, based on biological life cycles and phylogenetic reconstruction. Four types of life cycles, based on parasite vector, vertebrate host and the characteristics of their development, are defined. We propose combining species, based on their biology, into four groups (types I, II, III and IV). The characters of each type are defined and associated with a type genus and a type species. The biological characters of each type are associated with a different genus and a type species. The phylogenetic reconstruction with sequences deposited in the databases and our own new sequence of Hemolivia stellata is consistent with this classification. The classification is as follows: Type I, Hepatozoon Miller, 1908, type species H. perniciosum Miller, 1908; Type II, Karyolysus Labbé, 1894, type species K. lacertae (Danilewsky, 1886) Reichenow, 1913; Type III Hemolivia Petit et al., 1990, type species H. stellata, Petit et al., 1990; and Type IV: Bartazoon n. g., type species B. breinli (Mackerras, 1960).