Most mosquito-transmitted pathogens grow or replicate in the midgut before invading the salivary glands. Pathogens are exposed to several immunological factors along the way. Recently, it was shown that hemocytes gather near the periostial region of the heart to efficiently phagocytose pathogens circulating in the hemolymph.
View Article and Find Full Text PDFMost insects exhibit high reproductive capacity, which demands large amounts of energy, including macronutrients and micronutrients. Interestingly, many proteins involved in oogenesis depend on metals ions, in particular iron (Fe), zinc (Zn), and copper (Cu). Mechanisms by which metal ions influence reproduction have been described in Drosophila melanogaster, but remain poorly understood in hematophagous insects where blood meals include significant ingestion of metal ions.
View Article and Find Full Text PDFImmunological priming in insects is defined as a previous contact with non-virulent pathogens, which induces protection after a second virulent infection. The mechanism of this process is not well understood. We have observed midgut DNA synthesis (endoreplication) in Plasmodium berghei exposure mosquitoes (primed) and after the immune challenge, which could be an essential component of the priming response in the mosquito.
View Article and Find Full Text PDFIron and copper chelation restricts Plasmodium growth in vitro and in mammalian hosts. The parasite alters metal homeostasis in red blood cells to its favor, for example metabolizing hemoglobin to hemozoin. Metal interactions with the mosquito have not, however, been studied.
View Article and Find Full Text PDFIn invertebrates, "immunological priming" is considered as the ability to acquire a protective (adaptive) immune response against a pathogen due to previous exposure to the same organism. To date, the mechanism by which this type of adaptive immune response originates in insects is not well understood. In the Anopheles albimanus - Plasmodium berghei model, a DNA synthesis that probably indicates an endoreplication process during priming induction has been evidenced.
View Article and Find Full Text PDFDifferent evidences suggest that pericardial cells play an important role during the immune response against pathogens that invade the mosquito hemocoel. Previously, we identified two lysozyme genes in Anopheles albimanus heart transcriptome. The present study showed that one of these genes (ID: AALB004517) has high percentage of identity to mosquito lysozyme genes related to immunity, suggesting its possible participation during the mosquito immune response.
View Article and Find Full Text PDFIn hematophagous insects, the midgut is a fundamental barrier against infections and limits the development and transmission of pathogens. However, in mosquitoes, cell differentiation, proliferation, and cell cycle process in the midgut have not been characterized. Here we provide evidence of how cell cycle progression occurs in the newly emerged Anopheles albimanus mosquito midgut and describing cyclins expression as mediators of the cell cycle.
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