Effect of pollen extract supplementation on the varroatosis tolerance of honey bee (Apis mellifera) larvae reared in vitro.

As the main source of lipids and proteins in honey bees, pollen is a major nutrient provider involved in development and health and has been studied for tolerance stimulation against pathogens and parasites. In the case of Varroa destructor Anderson & Trueman (Acari, Mesostigmata: Varroidae) parasitization, the lack of a complete laboratory system to rear both the bee larva and the acarian parasite limited the studies concerning larval nutrition effects on the bee tolerance and resistance against varroatosis. Due to the development of this complete rearing protocol, we managed to feed young honey bee larvae with pollen supplemented solutions and to study the effect on their later development under parasitism conditions.

Impact of the Phoretic Phase on Reproduction and Damage Caused by Varroa destructor (Anderson and Trueman) to Its Host, the European Honey Bee (Apis mellifera L.).

Varroa destructor is a parasitic mite of the honeybee that causes thousands of colony losses worldwide. The parasite cycle is composed of a phoretic and a reproductive phase. During the former, mites stay on adult bees, mostly on nurses, to feed on hemolymph.

Assessment of immunogenicity and protective efficacy of Microsporum canis secreted components coupled to monophosphoryl lipid-A adjuvant in a vaccine study using guinea pigs.

Microsporum canis is the most common dermatophyte in pets and is of zoonotic importance but currently there is no effective vaccine available to prevent dermatophytosis. The aim of this work was to assess the immunogenicity and protective efficacy of secreted components (SC) from M. canis adjuvanted with the monophosphoryl lipid-A (MPLA), in a vaccine study using the guinea pig as an experimental model.

Lethal and sub-lethal effects of thymol on honeybee (Apis mellifera) larvae reared in vitro.

Background: Thymol offers an attractive alternative to synthetic chemicals to keep Varroa under control. However, thymol accumulates in bee products and is suspected of having adverse effects on colonies and especially on larvae. In this study, we investigated the effects of acute and chronic exposure to thymol on larvae reared in vitro with contaminated food and compared results to the theoretical larval exposure based on the amount of pollen and honey consumed by larvae during their development.

Artificial feeding of Varroa destructor through a chitosan membrane: a tool for studying the host-microparasite relationship.

Rearing pests or parasites of very small size in the absence of their living host is a challenge for behavioural, physiological and pathological studies. For feeding Varroa destructor, an ectoparasitic mite of Apis mellifera, a confinement space with a membrane separating the nutritive solution and the space was designed. The mite measures less than 2 mm and bears a perforating apparatus with a length of 15 μm.

Feline polymorphonuclear neutrophils produce pro-inflammatory cytokines following exposure to Microsporum canis.

The mechanisms involved in the establishment of the specific immune response against dermatophytes remain unknown. Polymorphonuclear neutrophils (PMNs) are recruited early during the infection process and participate in the elimination of dermatophytes. They could therefore be involved in the induction of the immune response during dermatophytoses by producing specific cytokines.

Fungalysin and dipeptidyl-peptidase gene transcription in Microsporum canis strains isolated from symptomatic and asymptomatic cats.

Microsporum canis is the main pathogenic fungus that causes a superficial cutaneous infection called dermatophytosis in domestic carnivores. In cats, M. canis causes symptomatic or asymptomatic infection.

Secreted dipeptidyl peptidases as potential virulence factors for Microsporum canis.

Dermatophytoses caused by Microsporum canis are frequently encountered in cats and dogs; they are highly contagious and readily transmissible to humans. In this study, two single genes, respectively coding for dipeptidyl peptidases IV and V (DppIV and DppV), were isolated and characterized. Both proteins share homology with serine proteases of the S9 family, some of which display properties compatible with implication in pathogenic processes.

Secreted subtilisins of Microsporum canis are involved in adherence of arthroconidia to feline corneocytes.

Microsporum canis is a pathogenic fungus that causes a superficial cutaneous infection called dermatophytosis, mainly in cats and humans. The mechanisms involved in adherence of M. canis to epidermis have never been investigated.

Pathogenesis of dermatophytosis.

Despite the superficial localization of most dermatophytosis, host-fungus relationship in these infections is complex and still poorly elucidated. Though many efforts have been accomplished to characterize secreted dermatophytic proteases at the molecular level, only punctual insights have been afforded into other aspects of the pathogenesis of dermatophytosis, such as fungal adhesion, regulation of gene expression during the infection process, and immunomodulation by fungal factors. However, new genetic tools were recently developed, allowing a more rapid and high-throughput functional investigation of dermatophyte genes and the identification of new putative virulence factors.

Reconstructed interfollicular feline epidermis as a model for the screening of antifungal drugs against Microsporum canis.

A fully differentiated reconstructed interfollicular feline epidermis (RFE) was recently developed in vitro. It was shown to be relevant for the study of Microsporum canis-epidermal interactions. In this study, RFE was evaluated as a potential model for the in vitro screening of drugs against M.

Immunization and dermatophytes.

Purpose Of Review: Despite the availability of effective vaccines for certain animal species, vaccination against dermatophytosis requires improvement and further development in both animals and humans. This review provides an update on the current situation and focuses on recent advances in host-dermatophyte relationships that could have implications for future vaccination against the most prevalent of the fungal diseases.

Recent Findings: Numerous dermatophytic virulence factors have recently been isolated and characterized at the molecular level, notably secreted proteases involved in the invasion of the keratin network.

RNA silencing in the dermatophyte Microsporum canis.

Dermatomycoses caused by Microsporum canis are frequent in domestic animals and easily transmissible to humans. Several proteases secreted by this fungus were identified as potential virulence factors, but the construction of deficient strains is required to investigate their role in the pathogenesis of the disease. Using target genes encoding two of these proteases, a first evaluation of the utility of RNA-mediated silencing as a reverse genetic tool in dermatophytes was carried out.

Reconstructed interfollicular feline epidermis as a model for Microsporum canis dermatophytosis.

Microsporum canis is a pathogenic fungus that causes a superficial cutaneous infection called dermatophytosis. The complexity of mechanisms involved in dermatophytic infections makes relevant in vivo studies particularly difficult to perform. The aim of this study was to develop a new in vitro model of M.