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Iliano V. Coutinho-Abreu

Bio: Iliano V. Coutinho-Abreu is an academic researcher from National Institutes of Health. The author has contributed to research in topics: Leishmania & Leishmania major. The author has an hindex of 16, co-authored 41 publications receiving 825 citations. Previous affiliations of Iliano V. Coutinho-Abreu include Federal University of Pernambuco & University of Notre Dame.

Papers
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Journal ArticleDOI
TL;DR: The current status of transgenesis and paratransgenesis is highlighted, pointing out advantages and constraints, and issues that need to be resolved are explored before the establishment of transGenesis andParatransGenesis as tools to prevent vector-borne diseases.

151 citations

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TL;DR: It is demonstrated that gut microbes from the sand fly are egested into host skin alongside Leishmania parasites, indicating that both gut microbiota and IL-1β are important for the establishment of Leishmaniasis infections.

133 citations

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TL;DR: It is shown that ingestion of a second uninfected blood meal by Leishmania-infected sand flies triggers dedifferentiation of metacyclic promastigotes to a replicative form, termed the retroleptomonad promastsigote, which amplifies parasite numbers in the flies.
Abstract: Sand flies, similar to most vectors, take multiple blood meals during their lifetime1-4. The effect of subsequent blood meals on pathogens developing in the vector and their impact on disease transmission have never been examined. Here, we show that ingestion of a second uninfected blood meal by Leishmania-infected sand flies triggers dedifferentiation of metacyclic promastigotes, considered a terminally differentiated stage inside the vector 5 , to a leptomonad-like stage, the retroleptomonad promastigote. Reverse metacyclogenesis occurs after every subsequent blood meal where retroleptomonad promastigotes rapidly multiply and differentiate to metacyclic promastigotes enhancing sand fly infectiousness. Importantly, a subsequent blood meal amplifies the few Leishmania parasites acquired by feeding on infected hosts by 125-fold, and increases lesion frequency by fourfold, in twice-fed compared with single-fed flies. These findings place readily available blood sources as a critical element in transmission and propagation of vector-borne pathogens.

103 citations

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TL;DR: An attenuated knock-out Leishmania (LmCen−/−) vaccine that is safe in immunocompromised mice and induces an immune response and protection similar to leishmanization with wild-type Leishmanniasis is engineer.
Abstract: Leishmaniasis is a neglected tropical disease caused by Leishmania protozoa transmitted by infected sand flies. Vaccination through leishmanization with live Leishmania major has been used successfully but is no longer practiced because it resulted in occasional skin lesions. A second generation leishmanization is described here using a CRISPR genome edited L. major strain (LmCen-/-). Notably, LmCen-/- is a genetically engineered centrin gene knock-out mutant strain that is antibiotic resistant marker free and does not have detectable off-target mutations. Mice immunized with LmCen-/- have no visible lesions following challenge with L. major-infected sand flies, while non-immunized animals develop large and progressive lesions with a 2-log fold higher parasite burden. LmCen-/- immunization results in protection and an immune response comparable to leishmanization. LmCen-/- is safe since it is unable to cause disease in immunocompromised mice, induces robust host protection against vector sand fly challenge and because it is marker free, can be advanced to human vaccine trials.

61 citations

Journal ArticleDOI
TL;DR: In this review, many of the TBV strategies against insect-borne pathogens and their respective ramification with regards to the immune response of the vertebrate host are discussed.
Abstract: Insect-borne diseases are responsible for severe mortality and morbidity worldwide. As control of insect vector populations relies primarily on the use of insecticides, the emergence of insecticide resistance as well to unintended consequences of insecticide use pose significant challenges to their continued application. Novel approaches to reduce pathogen transmission by disease vectors are been attempted, including transmission-blocking vaccines (TBVs) thought to be a feasible strategy to reduce pathogen burden in endemic areas. TBVs aim at preventing the transmission of pathogens from infected to uninfected vertebrate host by targeting molecule(s) expressed on the surface of pathogens during their developmental phase within the insect vector or by targeting molecules expressed by the vectors. For pathogen-based molecules, the majority of the TBV candidates selected as well as most of the data available regarding the effectiveness of this approach come from studies using malaria parasites. However, TBV candidates also have been identified from midgut tissues of mosquitoes and sand flies. In spite of the successes achieved in the potential application of TBVs against insect-borne diseases, many significant barriers remain. In this review, many of the TBV strategies against insect-borne pathogens and their respective ramification with regards to the immune response of the vertebrate host are discussed.

55 citations


Cited by
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Journal Article
Fumio Tajima1
30 Oct 1989-Genomics
TL;DR: It is suggested that the natural selection against large insertion/deletion is so weak that a large amount of variation is maintained in a population.

11,521 citations

Journal ArticleDOI

3,734 citations

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TL;DR: Gut bacteria of other insects have also been shown to contribute to nutrition, protection from parasites and pathogens, modulation of immune responses, and communication, and the extent of these roles is still unclear and awaits further studies.
Abstract: Insect guts present distinctive environments for microbial colonization, and bacteria in the gut potentially provide many beneficial services to their hosts. Insects display a wide range in degree of dependence on gut bacteria for basic functions. Most insect guts contain relatively few microbial species as compared to mammalian guts, but some insects harbor large gut communities of specialized bacteria. Others are colonized only opportunistically and sparsely by bacteria common in other environments. Insect digestive tracts vary extensively in morphology and physicochemical properties, factors that greatly influence microbial community structure. One obstacle to the evolution of intimate associations with gut microorganisms is the lack of dependable transmission routes between host individuals. Here, social insects, such as termites, ants, and bees, are exceptions: social interactions provide opportunities for transfer of gut bacteria, and some of the most distinctive and consistent gut communities, with specialized beneficial functions in nutrition and protection, have been found in social insect species. Still, gut bacteria of other insects have also been shown to contribute to nutrition, protection from parasites and pathogens, modulation of immune responses, and communication. The extent of these roles is still unclear and awaits further studies.

1,633 citations

Journal ArticleDOI
TL;DR: This review has gathered information on current definitions, serotypes, lineages, virulence mechanisms, epidemiology, and diagnosis of the major diarrheagenic E. coli pathotypes.

896 citations

Journal ArticleDOI
21 Sep 2011-PLOS ONE
TL;DR: Gut community structure was similar in the adult stage between the field and laboratory mosquitoes, indicating that mosquito gut is a selective eco-environment for its microbiome, and suggests a concerted symbiotic genetic association between gut inhabitants and host.
Abstract: The mosquito gut represents an ecosystem that accommodates a complex, intimately associated microbiome. It is increasingly clear that the gut microbiome influences a wide variety of host traits, such as fitness and immunity. Understanding the microbial community structure and its dynamics across mosquito life is a prerequisite for comprehending the symbiotic relationship between the mosquito and its gut microbial residents. Here we characterized gut bacterial communities across larvae, pupae and adults of Anopheles gambiae reared in semi-natural habitats in Kenya by pyrosequencing bacterial 16S rRNA fragments. Immatures and adults showed distinctive gut community structures. Photosynthetic Cyanobacteria were predominant in the larval and pupal guts while Proteobacteria and Bacteroidetes dominated the adult guts, with core taxa of Enterobacteriaceae and Flavobacteriaceae. At the adult stage, diet regime (sugar meal and blood meal) significantly affects the microbial structure. Intriguingly, blood meals drastically reduced the community diversity and favored enteric bacteria. Comparative genomic analysis revealed that the enriched enteric bacteria possess large genetic redox capacity of coping with oxidative and nitrosative stresses that are associated with the catabolism of blood meal, suggesting a beneficial role in maintaining gut redox homeostasis. Interestingly, gut community structure was similar in the adult stage between the field and laboratory mosquitoes, indicating that mosquito gut is a selective eco-environment for its microbiome. This comprehensive gut metatgenomic profile suggests a concerted symbiotic genetic association between gut inhabitants and host.

478 citations