المؤلفون: Raquel Martín-Hernández, Angeles Juarranz, Pilar García-Palencia, Silvia Rocío Lucena, Mariano Higes, Joyce Dias-Almeida, Cristina Botías, Aránzazu Meana

المصدر: Environmental Microbiology Reports. 5:530-536

مصطلحات موضوعية: Programmed cell death, Intracellular parasite, fungi, Honey bee, Biology, biology.organism_classification, Agricultural and Biological Sciences (miscellaneous), Nosema ceranae, Microbiology, Apoptosis, Microsporidia, Immunology, Parasite hosting, Pathogen, Ecology, Evolution, Behavior and Systematics

الوصف: Nosema ceranae is a parasite of the epithelial ventricular cells of the honey bee that belongs to the microsporidian phylum, a biological group of single-cell, spore-forming obligate intracellular parasites found in all major animal lineages. The ability of host cells to accommodate a large parasitic burden for several days suggests that these parasites subvert the normal host cells to ensure optimal environmental conditions for growth and development. Once infected, cells can counteract the invasive pathogen by initiating their own death by apoptosis as a defence strategy. To determine whether N. ceranae blocks apoptosis in infected ventricular cells, cell death was assessed in sections of the ventriculum from experimentally infected honey bees using the TUNEL assay and by immunohistochemistry for caspase-3. Ventricular epithelial cells from infected bees were larger than those in the uninfected control bees, and they contained N. ceranae at both mature and immature stages in the cytoplasm. Apoptotic nuclei were only observed in some restricted areas of the ventriculum, whereas apoptosis was typically observed throughout the epithelium in uninfected bees. Indeed, the apoptotic index was higher in uninfected versus infected ventriculi. Our results suggested that N. ceranae prevents apoptosis in epithelial cells of infected ventriculi, a mechanism possible designed to enhance parasite development.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::b82136c79babe404caee04b5cd7e6555Test
https://doi.org/10.1111/1758-2229.12059Test

المؤلفون: Mariano Higes, Pilar Marin, Mª Pilar Marín García, Aránzazu Meana Mañes, Raquel Martín Hernández, Amelia V. González-Porto, Pilar García Palencia

المصدر: Journal of Apicultural Research. 49:278-283

مصطلحات موضوعية: Beekeeping, Ventriculus, biology, Apiary, fungi, food and beverages, Zoology, Honey bee, biology.organism_classification, medicine.disease_cause, Nosema ceranae, Insect Science, Pollen, Botany, Microsporidia, behavior and behavior mechanisms, medicine, Parasite hosting

الوصف: SummaryIn this report, the pathological features observed in honey bees naturally infected with the microsporidium Nosema ceranae throughout a year are described. The lesions produced under natural conditions are similar to those observed in experimentally caged worker honey bees. N. ceranae is able to reproduce inside epithelial cells and multiply all through the year causing lesions in host-cells, characterized by a progressive and irreversible destruction of the epithelial layer of the ventriculus, which can lead to major negative repercussions on the normal process of digestion, with critical consequences on honey bee and colony viability. It is remarkable that factors such as continuous access to fresh pollen around the apiary or temperature and humidity variations throughout the year in different seasons did not apparently influence the development of the endogenous cycle of this parasite under field conditions.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::db9505cf31408dec5083d5ff808c427dTest
https://doi.org/10.3896/ibra.1.49.3.08Test

المؤلفون: Raquel Martín-Hernández, Yves Le Conte, Soledad Sagastume, Claudia Dussaubat, Pilar García-Palencia, Mariano Higes, Cristina Botías, Tamara Gómez-Moracho

المساهمون: Abeilles & Environnement (UR 406 ), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centro Apicola Regional (CAR), Direccion General de la Produccion Agropecuaria, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Instituto de Recursos Humanos para la Ciencia y Tecnologia, Partenaires INRAE

المصدر: Veterinary Microbiology
Veterinary Microbiology, Elsevier, 2013, 162 (2-4), pp.670-678. ⟨10.1016/j.vetmic.2012.09.012⟩

مصطلحات موضوعية: 0106 biological sciences, Veterinary medicine, [SDV]Life Sciences [q-bio], Molecular Sequence Data, Subspecies, 01 natural sciences, Microbiology, complex mixtures, 03 medical and health sciences, Nosema, nosema ceranae, Botany, Genetic variation, genetic variability, Animals, Parasite hosting, Genetic variability, 030304 developmental biology, 0303 health sciences, Base Sequence, Virulence, General Veterinary, biology, digestive, oral, and skin physiology, fungi, Genetic Variation, food and beverages, General Medicine, Honey bee, Bees, apis mellifera iberiensis, biology.organism_classification, Apis mellifera iberiensis, Nosema ceranae, 010602 entomology, isolates, Spain, Microsporidia, behavior and behavior mechanisms, pathology, France

الوصف: International audience; The intestinal honey bee parasite Nosema ceranae (Microsporidia) is at the root of colony losses in some regions while in others its presence causes no direct mortality. This is the case for Spain and France, respectively. It is hypothesized that differences in honey bee responses to N. ceranae infection could be due to the degree of virulence of N. ceranae strains from different geographic origins. To test this hypothesis, we first performed a study to compare the genetic variability of an rDNA fragment that could reveal differences between two N. ceranae isolates, one from Spain and one from France. Then we compared the infection capacity of both isolates in Apis mellifera iberiensis, based on the anatomopathological lesions due to N. ceranae development in the honey bee midgut, N. ceranae spore-load in the midgut and the honey bee survival rate. Our results suggest that there is no specific genetic background of the two N. ceranae isolates, from Spain or France, used in this study. These results agree with the infection development, honey bee survival and spore-loads that were similar between honey bees infected with both N. ceranae isolates. Probably, differences in honey bee response to infection are more related to the degree of tolerance of honey bee subspecies or local hybrids to N. ceranae, or experimental conditions in the case of laboratory trials, than to differences between N. ceranae isolates. Further studies should be done to estimate the contribution of each of these factors on the response of the honey bees to infection.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a289b22d1651c100afa955cc954af2b6Test
https://hal.inrae.fr/hal-02646329Test

المؤلفون: Mariano Higes, Aránzazu Meana, Encarna Garrido-Bailón, Pilar García-Palencia, Cristina Botías, Raquel Martín-Hernández

المصدر: Environmental microbiology. 10(5)

مصطلحات موضوعية: Infectivity, biology, Ecology, fungi, Zoology, Insectivore, Bees, Spores, Fungal, biology.organism_classification, Microbiology, Nosema ceranae, Spore, Birds, Nosema, Fomites, Predatory Behavior, Microsporidia, Microsporidiosis, Disease Transmission, Infectious, Parasite hosting, Animals, Ecology, Evolution, Behavior and Systematics, Merops apiaster

الوصف: The importance of transmission factor identification is of great epidemiological significance. The bee-eater (Merops apiaster) is a widely distributed insectivorous bird, locally abundant mainly in arid and semi-arid areas of southern Europe, northern Africa and western Asia but recently has been seen breeding in central Europe and Great Britain. Bee-eaters predominantly eat insects, especially bees, wasps and hornets. On the other hand, Nosema ceranae is a Microsporidia recently described as a parasite in Apis mellifera honeybees in Europe. Due to the short time since its description scarce epidemiological data are available. In this study we investigate the role of the regurgitated pellets of the European bee-eater as fomites of infective spores of N. ceranae. Spore detection in regurgitated pellets of M. apiaster is described [phase-contrast microscopy (PCM) and polymerase chain reaction (PCR) methods]. Eighteen days after collection N. ceranae spores still remain viable and their infectivity is shown after artificial infection of Nosema-free 8-day-old adult bees. The epidemiological consequences of the presence of Nosema spores in this fomites are discussed.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9a59237372054e45c8b254b2ce93f32aTest
https://pubmed.ncbi.nlm.nih.gov/18218034Test

المؤلفون: Mariano Higes, Aránzazu Meana, Pilar García-Palencia, Raquel Martín-Hernández

المصدر: Journal of invertebrate pathology. 94(3)

مصطلحات موضوعية: Apidae, Inoculation, fungi, Genes, Fungal, Nosema apis, Anatomy, Sequence Analysis, DNA, Biology, Bees, biology.organism_classification, Nosema ceranae, Spore, Microbiology, Host-Parasite Interactions, Nosema, Microscopy, Electron, Transmission, RNA, Ribosomal, 16S, Microsporidia, Parasite hosting, Animals, Ecology, Evolution, Behavior and Systematics

الوصف: In this report, an experimental infection of Apis mellifera by Nosema ceranae, a newly reported microsporidian in this host is described. Nosema free honeybees were inoculated with 125,000 N. ceranae spores, isolated from heavily infected bees. The parasite species was identified by amplification and sequencing the SSUrRNA gene of the administered spores. Three replicate cages of 20 honeybees each were prepared, along with one control cage (n=20) supplied with sugar syrup only. The infection rate was 100% at the dosage administered. The presence of Nosema inside ventricular cells was confirmed in the samples using ultrathin sectioning and transmission electron microscopy. By day 3 p.i. a few cells (4.4%+/-1.2) were observed to be parasitized, whereas by 6 days p.i. more than half of the counted cells (66.4%+/-6) showed different parasite stages, this value increasing on day 7 p.i. (81.5%+/-14.8). Only one control bee died on day 7 p.i. In the infected groups, mortality was not observed until day 6 p.i. (66.7%+/-5.6). Total mortality on day 7 p.i. was 94.1% in the three infected replicates and by day 8 p.i. no infected bee was alive. After the infection, the parasites invaded both the tip of folds and the basal cells of the epithelium and the autoinfective capacity of the spores seemed to spread the infection rapidly between epithelial cells. On day 3 p.i., mature spores could be seen inside host cell tissue implying that the developmental cycle had been completed. The large number of parasitized cells, even the regenerative ones, the presence of autoinfective spores and the high mortality rate demonstrate that N. ceranae is highly pathogenic to Apis mellifera. Possible relation with bee depopulation syndrome is discussed by authors.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::471ec8484617096e770760d5cfddbf5bTest
https://pubmed.ncbi.nlm.nih.gov/17217954Test