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leishmania major survival in selective phlebotomus papatasi sand fly vector requires a specific scg-encoded lipophosphoglycan galactosylation pattern.phlebotomine sand flies that transmit the protozoan parasite leishmania differ greatly in their ability to support different parasite species or strains in the laboratory: while some show considerable selectivity, others are more permissive. in "selective" sand flies, leishmania binding and survival in the fly midgut typically depends upon the abundant promastigote surface adhesin lipophosphoglycan (lpg), which exhibits species- and strain-specific modifications of the dominant phosphoglycan (pg ...201021085609
the protective effect against leishmania infection conferred by sand fly bites is limited to short-term exposure.under laboratory conditions, hosts exposed twice to sand fly saliva are protected against severe leishmaniasis. however, people in endemic areas are exposed to the vector over a long term and may experience sand fly-free periods. therefore, we exposed mice long- or short-term to phlebotomus duboscqi bites, followed by leishmania major infection either immediately or after a sand fly-free period. we showed that protection against leishmaniasis is limited to short-term exposure to sand flies immed ...201121310158
bacterial flora as indicated by pcr-temperature gradient gel electrophoresis (tgge) of 16s rdna gene fragments from isolated guts of phlebotomine sand flies (diptera: psychodidae).in this study, we tested the capacity of temperature gradient gel electrophoresis (tgge)-based fingerprinting of 16s rdna pcr fragments to assess bacterial composition in a single isolated sand fly gut. bacterial content was studied in different life stages of a laboratory-reared colony of phlebotomus duboscqi and in a wild-caught phlebotomus papatasi population. our study demonstrates that a major reorganization in the gut bacterial community occurs during metamorphosis of sand flies. chlorofle ...201121366767
pathogenicity of metarhizium anisopliae (metch) sorok and beauveria bassiana (bals) vuill to adult phlebotomus duboscqi (neveu-lemaire) in the laboratory.biological control of sandflies using entomopathogenic fungi is a possible alternative to the expensive synthetic chemical control. it is potentially sustainable, less hazardous, and relatively inexpensive and merits further investigations. the objective of this study was to identify the most pathogenic fungal isolate(s) to sandflies in the laboratory.201121406735
sandfly-saliva injected during repeated feeding on a sensitized hamster causes fecundity and mortality to female phlebotomus duboscqi (diptera: psychodidae). 201121406740
ecology of phlebotomine sand flies in the rural community of mont rolland (thiès region, senegal): area of transmission of canine leishmaniasis.different epidemiological studies previously indicated that canine leishmaniasis is present in the region of thiès (senegal). however, the risks to human health, the transmission cycle and particularly the implicated vectors are unknown.201121445295
the midgut transcriptome of phlebotomus (larroussius) perniciosus, a vector of leishmania infantum: comparison of sugar fed and blood fed sand flies.abstract:201121569254
seasonality and prevalence of leishmania major infection in phlebotomus duboscqi neveu-lemaire from two neighboring villages in central mali.phlebotomus duboscqi is the principle vector of leishmania major, the causative agent of cutaneous leishmaniasis (cl), in west africa and is the suspected vector in mali. although found throughout the country the seasonality and infection prevalence of p. duboscqi has not been established in mali. we conducted a three year study in two neighboring villages, kemena and sougoula, in central mali, an area with a leishmanin skin test positivity of up to 45%. during the first year, we evaluated the o ...201121572984
visualisation of leishmania donovani fluorescent hybrids during early stage development in the sand fly vector.the leishmania protozoan parasites cause devastating human diseases. leishmania have been considered to replicate clonally, without genetic exchange. however, an accumulation of evidence indicates that there are inter-specific and intra-specific hybrids among natural populations. the first and so far only experimental proof of genetic exchange was obtained in 2009 when double drug resistant leishmania major hybrids were produced by co-infecting sand flies with two strains carrying different drug ...201121637755
infection parameters in the sand fly vector that predict transmission of leishmania major.to identify parameters of leishmania infection within a population of infected sand flies that reliably predict subsequent transmission to the mammalian host, we sampled groups of infected flies and compared infection intensity and degree of metacyclogenesis with the frequency of transmission. the percentage of parasites within the midgut that were metacyclic promastigotes had the highest correlation with the frequency of transmission. meta-analysis of multiple transmission experiments allowed u ...201121886852
nucleosides from phlebotomus papatasi salivary gland ameliorate murine collagen-induced arthritis by impairing dendritic cell functions.among several pharmacological compounds, phlebotomine saliva contains substances with anti-inflammatory properties. in this article, we demonstrated the therapeutic activity of salivary gland extract (sge) of phlebotomus papatasi in an experimental model of arthritis (collagen-induced arthritis [cia]) and identified the constituents responsible for such activity. daily administration of sge, initiated at disease onset, attenuated the severity of cia, reducing the joint lesion and proinflammatory ...201121930966
Human cellular immune response to the saliva of Phlebotomus papatasi is mediated by IL-10-producing CD8+ T cells and Th1-polarized CD4+ lymphocytes.The saliva of sand flies strongly enhances the infectivity of Leishmania in mice. Additionally, pre-exposure to saliva can protect mice from disease progression probably through the induction of a cellular immune response.201121991402
evaluation of ulv applications against old world sand fly (diptera: psychodidae) species in equatorial kenya.reducing populations of phlebotomine sand flies in areas prevalent for human leishmaniases is of ongoing importance to united states military operations and civilian populations in endemic regions. however, not enough is known regarding the efficacy of department of defense-approved pesticides and equipment against sand flies; specifically, the potential for ultra-low volume (ulv) pesticide applications to control old world sand fly vectors. in this study we examine two sprayers, the terminator ...201122238873
evaluation of three feed-through insecticides using two rodent and two sand fly species as models.the efficacy of 3 rodent feed-through insecticides (novaluron, pyriproxyfen, and ivermectin) was determined against larvae of the sand flies phlebotomus duboscqi and p. papatasi using syrian hamsters (mesocricetus auratus) and mongolian gerbils (meriones unguiculatus) as laboratory models. for each insecticide, there were no significant differences between the longevity or percentage survival of sand fly larvae that had been fed feces of treated rodents for each sand fly or rodent species pairin ...201223833909
cruzipain promotes trypanosoma cruzi adhesion to rhodnius prolixus midgut.trypanosoma cruzi is the etiological agent of chagas' disease. cysteine peptidases are relevant to several aspects of the t. cruzi life cycle and are implicated in parasite-mammalian host relationships. however, little is known about the factors that contribute to the parasite-insect host interaction.201223272264
first detection of leishmania major dna in sergentomyia (spelaeomyia) darlingi from cutaneous leishmaniasis foci in mali.leishmania major complex is the main causative agent of zoonotic cutaneous leishmaniasis (zcl) in the old world. phlebotomus papatasi and phlebotomus duboscqi are recognized vectors of l. major complex in northern and southern sahara, respectively. in mali, zcl due to l. major is an emerging public health problem, with several cases reported from different parts of the country. the main objective of the present study was to identify the vectors of leishmania major in the bandiagara area, in mali ...201222276095
incrimination of phlebotomus kandelakii and phlebotomus balcanicus as vectors of leishmania infantum in tbilisi, georgia.a survey of potential vector sand flies was conducted in the neighboring suburban communities of vake and mtatsminda districts in an active focus of visceral leishmaniasis (vl) in tbilisi, georgia. using light and sticky-paper traps, 1,266 male and 1,179 female sand flies were collected during 2006-2008. five phlebotomus species of three subgenera were collected: phlebotomus balcanicus theodor and phlebotomus halepensis theodor of the subgenus adlerius; phlebotomus kandelakii shchurenkova and ph ...201222509422
caspar-like gene depletion reduces leishmania infection in sand fly host lutzomyia longipalpis.female phlebotomine sand flies lutzomyia longipalpis naturally harbor populations of the medically important leishmania infantum (syn. leishmania chagasi) parasite in the gut, but the extent to which the parasite interacts with the immune system of the insect vector is unknown. to investigate the sand fly immune response and its interaction with the leishmania parasite, we identified a homologue for caspar, a negative regulator of immune deficiency signaling pathway. we found that feeding antibi ...201222375009
the development of leishmania turanica in sand flies and competition with l. major.in central asian foci of zoonotic cutaneous leishmaniases, mixed infections of leishmania turanica and l. major have been found in a reservoir host (the great gerbil, rhombomys opimus) as well as in the sand fly vector phlebotomus papatasi, but hybrids between these two leishmania species have never been reported. in addition, the role of sand fly species other than p. papatasi in l. turanica circulation is not clear.201223031344
the immune response to sand fly salivary proteins and its influence on leishmania immunity.leishmaniasis is a vector-borne disease transmitted by bites of phlebotomine sand flies. during leishmania transmission, sand fly saliva is co-inoculated with parasites into the skin of the mammalian host. sand fly saliva consists of roughly thirty different salivary proteins, many with known roles linked to blood feeding facilitation. apart from the anti-hemostatic capacity of saliva, several sand fly salivary proteins have been shown to be immunogenic. immunization with a single salivary prote ...201222593758
tsetse fly saliva: could it be useful in fly infection when feeding in chronically aparasitemic mammalian hosts.sleeping sickness and nagana are two important diseases cuased by african trypanosomes in humans and animals respectively, in tropical african countries. a number of trypanosome species are implicated in these diseases, but it is the trypanosoma brucei group that is responsible for the chronic form of sleeping sickness. during the course of this chronic infection the parasite shows a clear tropism for organs and tissues and only sporadically appears in the blood stream. notwithstanding this feat ...201226623300
leishmania development in sand flies: parasite-vector interactions overview.leishmaniases are vector-borne parasitic diseases with 0.9 - 1.4 million new human cases each year worldwide. in the vectorial part of the life-cycle, leishmania development is confined to the digestive tract. during the first few days after blood feeding, natural barriers to leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. as the blood digestion proceeds, parasites need to bind to the midgut ep ...201223206339
updating the salivary gland transcriptome of phlebotomus papatasi (tunisian strain): the search for sand fly-secreted immunogenic proteins for humans.sand fly saliva plays an important role in both blood feeding and outcome of leishmania infection. a cellular immune response against a phlebotomus papatasi salivary protein was shown to protect rodents against leishmania major infection. in humans, p. papatasi salivary proteins induce a systemic cellular immune response as well as a specific antisaliva humoral immune response, making these salivary proteins attractive targets as markers of exposure for this leishmania vector. surprisingly, the ...201223139741
the role of leishmania proteophosphoglycans in sand fly transmission and infection of the mammalian host.leishmania are transmitted by the bite of their sand fly vector and this has a significant influence on the virulence of the resulting infection. from our studies into the interaction between parasite, vector, and host we have uncovered an important missing ingredient during leishmania transmission. leishmania actively adapt their sand fly hosts into efficient vectors by secreting promastigote secretory gel (psg), a proteophosphoglycan (ppg)-rich, mucin-like gel which accumulates in sand fly gut ...201222754550
new insights on the inflammatory role of lutzomyia longipalpis saliva in leishmaniasis.when an haematophagous sand fly vector insect bites a vertebrate host, it introduces its mouthparts into the skin and lacerates blood vessels, forming a hemorrhagic pool which constitutes an intricate environment of cell interactions. in this scenario, the initial performance of host, parasite, and vector "authors" will heavily influence the course of leishmania infection. recent advances in vector-parasite-host interaction have elucidated "co-authors" and "new roles" not yet described. we revie ...201222506098
evaluation of recombinant leishmania polyprotein plus glucopyranosyl lipid a stable emulsion vaccines against sand fly-transmitted leishmania major in c57bl/6 mice.numerous experimental leishmania vaccines have been developed to prevent the visceral and cutaneous forms of leishmaniasis, which occur after exposure to the bite of an infected sand fly, yet only one is under evaluation in humans. ksac and l110f, recombinant leishmania polyproteins delivered in a stable emulsion (se) with the tlr4 agonists monophosphoryl lipid a or glucopyranosyl lipid a (gla) have shown protection in animal models. ksac+gla-se protected against cutaneous disease following sand ...201223045616
delayed-type hypersensitivity to sand fly saliva in humans from a leishmaniasis-endemic area of mali is th1-mediated and persists to midlife.immunity to sand fly saliva in rodents induces a t(h)1 delayed-type hypersensitivity (dth) response conferring protection against leishmaniasis. the relevance of dth to sand fly bites in humans living in a leishmaniasis-endemic area remains unknown. here, we describe the duration and nature of dth to sand fly saliva in humans from an endemic area of mali. dth was assessed at 24, 48, 72, and 96 hours post bite in volunteers exposed to colony-bred sand flies. dermal biopsies were obtained 48 hours ...201222992802
ksac, a defined leishmania antigen, plus adjuvant protects against the virulence of l. major transmitted by its natural vector phlebotomus duboscqi.recombinant ksac and l110f are promising leishmania vaccine candidates. both antigens formulated in stable emulsions (se) with the natural tlr4 agonist mpl® and l110f with the synthetic tlr4 agonist gla in se protected balb/c mice against l. major infection following needle challenge. considering the virulence of vector-transmitted leishmania infections, we vaccinated balb/c mice with either ksac+gla-se or l110f+gla-se to assess protection against l. major transmitted via its vector phlebotomus ...201222509423
sandflies (diptera: psychodidae) in a focus of visceral leishmaniasis in white nile, sudan.visceral leishmaniasis (vl) has been known to occur since the 1980s on the western bank of the white nile river (central sudan), 150 km south of khartoum, and has resulted in high mortality. the most recent outbreak of the disease in this area began in 2006. entomological surveys were carried out during may 2008, june 2010 and may and july 2011 in the white nile area. sandflies were collected using centers for disease control light traps and sticky oil traps in the village of kadaba and the near ...201222666856
experimental acquisition, development, and transmission of leishmania tropica by phlebotomus duboscqi.we report experimental infection and transmission of leishmania tropica (wright), by the blood-feeding sand fly phlebotomus duboscqi (neveu-lemaire). groups of laboratory-reared female sand flies that fed "naturally" on l. tropica-infected hamsters, or artificially, via membrane feeding device, on a suspension of l. tropica amastigotes, were dissected at progressive time points post-feeding. acquisition, retention and development of l. tropica through procyclic, nectomonad, and leptomonad stages ...201322975149
use of metarhizium anisopliae chitinase genes for genotyping and virulence characterization.virulence is the primary factor used for selection of entomopathogenic fungi (epf) for development as biopesticides. to understand the genetic mechanisms underlying differences in virulence of fungal isolates on various arthropod pests, we compared the chitinase genes, chi2 and chi4, of 8 isolates of metarhizium anisopliae. the clustering of the isolates showed various groups depending on their virulence. however, the analysis of their chitinase dna sequences chi2 and chi4 did not reveal major d ...201323936804
the mating competence of geographically diverse leishmania major strains in their natural and unnatural sand fly vectors.invertebrate stages of leishmania are capable of genetic exchange during their extracellular growth and development in the sand fly vector. here we explore two variables: the ability of diverse l. major strains from across its natural range to undergo mating in pairwise tests; and the timing of the appearance of hybrids and their developmental stage associations within both natural (phlebotomus duboscqi) and unnatural (lutzomyia longipalpis) sand fly vectors. following co-infection of flies with ...201323935521
salivary antigen-5/cap family members are cu2+-dependent antioxidant enzymes that scavenge o₂₋. and inhibit collagen-induced platelet aggregation and neutrophil oxidative burst.the function of the antigen-5/cap family of proteins found in the salivary gland of bloodsucking animals has remained elusive for decades. antigen-5 members from the hematophagous insects dipetalogaster maxima (dmav) and triatoma infestans (tiav) were expressed and discovered to attenuate platelet aggregation, atp secretion, and thromboxane a2 generation by low doses of collagen (<1 μg/ml) but no other agonists. dmav did not interact with collagen, glycoprotein vi, or integrin α2β1. this inhibit ...201323564450
sergentomyia schwetzi is not a competent vector for leishmania donovani and other leishmania species pathogenic to humans.sand fly species of the genus sergentomyia are proven vectors of reptilian leishmania that are non-pathogenic to humans. however, a consideration of the role of sergentomyia spp. in the circulation of mammalian leishmaniasis appears repeatedly in the literature and the possibility of leishmania transmission to humans remains unclear. here we studied the susceptibility of colonized sergentomyia schwetzi to leishmania donovani and two other leishmania species pathogenic to humans: l. infantum and ...201323786805
sand-fly saliva-leishmania-man: the trigger trio.leishmaniases are worldwide diseases transmitted to the vertebrate host by the bite of an infected sand-fly. sand-fly biting and parasite inoculation are accompanied by the injection of salivary molecules, whose immunomodulatory properties are actively being studied. this mini review focuses on how the interactions between sand-fly saliva and the immune system may shape the outcome of infection, given its immunomodulatory properties, in experimental models and in the endemic area. additionally, ...201324312093
molecular and immunogenic properties of apyrase sp01b and d7-related sp04 recombinant salivary proteins of phlebotomus perniciosus from madrid, spain.sand fly salivary proteins are on the spotlight to become vaccine candidates against leishmaniasis and to markers of exposure to sand fly bites due to the host immune responses they elicit. working with the whole salivary homogenate entails serious drawbacks such as the need for maintaining sand fly colonies and the laborious task of glands dissection. in order to overcome these difficulties, producing recombinant proteins of different vectors has become a major task. in this study, a cdna libra ...201324171166
a new model of progressive visceral leishmaniasis in hamsters by natural transmission via bites of vector sand flies.visceral leishmaniasis (vl) is transmitted by sand flies. protection of needle-challenged vaccinated mice was abrogated in vector-initiated cutaneous leishmaniasis, highlighting the importance of developing natural transmission models for vl.201323288926
effects of aedes aegypti salivary components on dendritic cell and lymphocyte biology.saliva is a key element of interaction between hematophagous mosquitoes and their vertebrate hosts. in addition to allowing a successful blood meal by neutralizing or delaying hemostatic responses, the salivary cocktail is also able to modulate the effector mechanisms of host immune responses facilitating, in turn, the transmission of several types of microorganisms. understanding how the mosquito uses its salivary components to circumvent host immunity might help to clarify the mechanisms of tr ...201324238038
the effect of avian blood on leishmania development in phlebotomus duboscqi.the development of pathogens transmitted by haematophagous invertebrate vectors is closely connected with the digestion of bloodmeals and is thus affected by midgut enzymatic activity. some studies have demonstrated that avian blood inhibits leishmania major infection in the old world vector phlebotomus papatasi; however, this effect has never been observed in the new world vectors of the genus lutzomyia infected by other leishmania species. therefore, our study was focused on the effect of chic ...201324059328
niakha virus: a novel member of the family rhabdoviridae isolated from phlebotomine sandflies in senegal.members of the family rhabdoviridae have been assigned to eight genera but many remain unassigned. rhabdoviruses have a remarkably diverse host range that includes terrestrial and marine animals, invertebrates and plants. transmission of some rhabdoviruses often requires an arthropod vector, such as mosquitoes, midges, sandflies, ticks, aphids and leafhoppers, in which they replicate. herein we characterize niakha virus (niav), a previously uncharacterized rhabdovirus isolated from phebotomine s ...201323773405
bacterial feeding, leishmania infection and distinct infection routes induce differential defensin expression in lutzomyia longipalpis.phlebotomine insects harbor bacterial, viral and parasitic pathogens that can cause diseases of public health importance. lutzomyia longipalpis is the main vector of visceral leishmaniasis in the new world. insects can mount a powerful innate immune response to pathogens. defensin peptides take part in this response and are known to be active against gram-positive and gram-negative bacteria, and some parasites. we studied the expression of a defensin gene from lutzomyia longipalpis to understand ...201323311993
extensive differences in antifungal immune response in two drosophila species revealed by comparative transcriptome analysis.the innate immune system of drosophila is activated by ingestion of microorganisms. d. melanogaster breeds on fruits fermented by saccharomyces cerevisiae, whereas d. virilis breeds on slime flux and decaying bark of tree housing a variety of bacteria, yeasts, and molds. in this study, it is shown that d. virilis has a higher resistance to oral infection of a species of filamentous fungi belonging to the genus penicillium compared to d. melanogaster. in response to the fungal infection, a transc ...201324151578
host modulation by a parasite: how leishmania infantum modifies the intestinal environment of lutzomyia longipalpis to favor its development.some reports have described the interference of leishmania on sand flies physiology, and such behavior most likely evolved to favor the development and transmission of the parasite. most of these studies showed that leishmania could modulate the level of proteases in the midgut after an infective blood meal, and decreased proteolytic activity is indeed beneficial for the development of promastigotes in the gut of sand flies. in the present study, we performed a detailed investigation of the inte ...201425365351
characterization of the early inflammatory infiltrate at the feeding site of infected sand flies in mice protected from vector-transmitted leishmania major by exposure to uninfected bites.mice exposed to sand fly saliva are protected against vector-transmitted leishmania major. although protection has been related to ifn-γ producing t cells, the early inflammatory response orchestrating this outcome has not been defined.201424762408
evidence for a lectin specific for sulfated glycans in the salivary gland of the malaria vector, anopheles gambiae.salivary gland homogenate (sgh) from the female mosquitoes anopheles gambiae, an. stephensi, an. freeborni, an. dirus and an. albimanus were found to exhibit hemagglutinating (lectin) activity. lectin activity was not found for male an. gambiae, or female ae aegypti, culex quinquefasciatus, phlebotomus duboscqi, and lutzomyia longipalpis. with respect to species-specificity, an. gambiae sgh agglutinates red blood cells (rbc) from humans, horse, sheep, goat, pig, and cow; it is less active for ra ...201425207644
chronic parasitic infection maintains high frequencies of short-lived ly6c+cd4+ effector t cells that are required for protection against re-infection.in contrast to the ability of long-lived cd8(+) memory t cells to mediate protection against systemic viral infections, the relationship between cd4(+) t cell memory and acquired resistance against infectious pathogens remains poorly defined. this is especially true for t helper 1 (th1) concomitant immunity, in which protection against reinfection coincides with a persisting primary infection. in these situations, pre-existing effector cd4 t cells generated by ongoing chronic infection, not memo ...201425473946
cross-species genetic exchange between visceral and cutaneous strains of leishmania in the sand fly vector.genetic exchange between leishmania major strains during their development in the sand fly vector has been experimentally shown. to investigate the possibility of genetic exchange between different leishmania species, a cutaneous strain of l. major and a visceral strain of leishmania infantum, each bearing a different drug-resistant marker, were used to coinfect lutzomyia longipalpis sand flies. eleven double-drug-resistant progeny clones, each the product of an independent mating event, were ge ...201425385616
wild gorillas as a potential reservoir of leishmania major.vector-borne parasites of the genus leishmania are responsible for severe human diseases. cutaneous leishmaniasis, a common form of the disease, is most often caused by the transmission of leishmania major to humans by female phlebotomine sand flies. apes are increasingly being seen as a source of zoonotic diseases, including malaria and rickettsiosis. to examine whether gorillas harbor leishmania species, we screened fecal samples from wild western lowland gorillas (gorilla gorilla gorilla) in c ...201425001460
site-dependent recruitment of inflammatory cells determines the effective dose of leishmania major.the route of pathogen inoculation by needle has been shown to influence the outcome of infection. employing needle inoculation of the obligately intracellular parasite leishmania major, which is transmitted in nature following intradermal (i.d.) deposition of parasites by the bite of an infected sand fly, we identified differences in the preexisting and acute cellular responses in mice following i.d. inoculation of the ear, subcutaneous (s.c.) inoculation of the footpad, or inoculation of the pe ...201424733090
first evidence of intraclonal genetic exchange in trypanosomatids using two leishmania infantum fluorescent transgenic clones.the mode of reproduction in leishmania spp has been argued to be essentially clonal. however, recent data (genetic analysis of populations and co-infections in sand flies) have proposed the existence of a non-obligate sexual cycle in the extracellular stage of the parasite within the sand fly vector. in this article we propose the existence of intraclonal genetic exchange in the natural vector of leishmania infantum.201425188587
multi-modal analysis of courtship behaviour in the old world leishmaniasis vector phlebotomus argentipes.the sand fly phlebotomus argentipes is arguably the most important vector of leishmaniasis worldwide. as there is no vaccine against the parasites that cause leishmaniasis, disease prevention focuses on control of the insect vector. understanding reproductive behaviour will be essential to controlling populations of p. argentipes, and developing new strategies for reducing leishmaniasis transmission. through statistical analysis of male-female interactions, this study provides a detailed descrip ...201425474027
differential roles of an anopheline midgut gpi-anchored protein in mediating plasmodium falciparum and plasmodium vivax ookinete invasion.novel strategies to directly thwart malaria transmission are needed to maintain the gains achieved by current control measures. transmission-blocking interventions (tbis), namely vaccines and drugs targeting parasite or mosquito molecules required for vector-stage parasite development, have been recognized as promising approaches for preventing malaria transmission. however, the number of tbi targets is limited and their degree of conservation among the major vector-parasite systems causing huma ...201424929123
niches, population structure and genome reduction in ochrobactrum intermedium: clues to technology-driven emergence of pathogens.ochrobactrum intermedium is considered as an emerging human environmental opportunistic pathogen with mild virulence. the distribution of isolates and sequences described in literature and databases showed frequent association with human beings and polluted environments. as population structures are related to bacterial lifestyles, we investigated by multi-locus approach the genetic structure of a population of 65 isolates representative of the known natural distribution of o. intermedium. the p ...201424465379
cell-to-cell transfer of leishmania amazonensis amastigotes is mediated by immunomodulatory lamp-rich parasitophorous extrusions.the last step of leishmania intracellular life cycle is the egress of amastigotes from the host cell and their uptake by adjacent cells. using multidimensional live imaging of long-term-infected macrophage cultures we observed that leishmania amazonensis amastigotes were transferred from cell to cell when the donor host macrophage delivers warning signs of imminent apoptosis. they were extruded from the macrophage within zeiotic structures (membrane blebs, an apoptotic feature) rich in phagolyso ...201424824158
interleukin 10-dominant immune response and increased risk of cutaneous leishmaniasis after natural exposure to lutzomyia intermedia sand flies.leishmaniasis is caused by parasites transmitted to the vertebrate host by infected sand flies. during transmission, the vertebrate host is also inoculated with sand fly saliva, which exerts powerful immunomodulatory effects on the host's immune response.201525596303
effect of leishmania spp infection on the survival, life expectancy, fecundity and fertility of lutzomyia longipalpiss.l. and lutzomyia pseudolongipalpis.we evaluated the effects of leishmaniaspp infection on several population parameters of lutzomyia longipalpis sensu lato andlutzomyia pseudolongipalpis, vectors of visceral leishmaniasis in venezuela, under experimental conditions during the first post-feeding period. females of both species were allowed to feed and engorge on a suspension of fresh washed human red blood cells in foetal calf serum. these blood cells were either non-infected or infected with one of the fourleishmaniaspp strains a ...201526132427
hyaluronidase activity in saliva of european culicoides (diptera: ceratopogonidae).biting midges of the genus culicoides transmit pathogens of veterinary importance such as bluetongue virus (reoviridae: orbivirus). the saliva of culicoides is known to contain bioactive molecules including peptides and proteins with vasodilatory and immunomodulative properties. in this study, we detected activity of enzyme hyaluronidase in six culicoides species that commonly occur in europe and that are putative vectors of arboviruses. hyaluronidase was present in all species studied, although ...201526487248
techniques to improve the maintenance of a laboratory colony of nyssomyia neivai (diptera: psychodidae).the most critical phase in sand fly colonization is the high mortality in the larval instars. in this study, we sought out strategies for improving the colonization of nyssomyia neivai, one of the vectors of cutaneous leishmaniasis agent in south america.201526276040
natural transmission of leishmania infantum through experimentally infected phlebotomus perniciosus highlights the virulence of leishmania parasites circulating in the human visceral leishmaniasis outbreak in madrid, spain.a human leishmaniasis outbreak is occurring in the madrid region, spain, with the parasite and vector involved being leishmania infantum and phlebotomus perniciosus respectively. the aim of this study was to investigate the virulence of l. infantum isolates from the focus using a natural transmission model. hamsters were infected by intraperitoneal inoculation (ip) or by bites of sand flies experimentally infected with l. infantum isolates obtained from p. perniciosus collected in the outbreak a ...201526645907
nucleosides present on phlebotomine saliva induce immunossuppression and promote the infection establishment.sand fly saliva plays a crucial role in establishing leishmania infection. we identified adenosine (ado) and adenosine monophosphate (amp) as active pharmacologic compounds present in phlebotomus papatasi saliva that inhibit dendritic cell (dc) functions through a pge2/il 10-dependent mechanism.201525849562
recent advances in phlebotomine sand fly research related to leishmaniasis control.phlebotomine sand flies are the subject of much research because of the role of their females as the only proven natural vectors of leishmania species, the parasitic protozoans that are the causative agents of the neglected tropical disease leishmaniasis. activity in this field was highlighted by the eighth international symposium on phlebotomine sand flies (isops) held in september 2014, which prompted this review focusing on vector control. topics reviewed include: taxonomy and phylogenetics, ...201525885217
immunogenicity and serological cross-reactivity of saliva proteins among different tsetse species.tsetse are vectors of pathogenic trypanosomes, agents of human and animal trypanosomiasis in africa. components of tsetse saliva (sialome) are introduced into the mammalian host bite site during the blood feeding process and are important for tsetse's ability to feed efficiently, but can also influence disease transmission and serve as biomarkers for host exposure. we compared the sialome components from four tsetse species in two subgenera: subgenus morsitans: glossina morsitans morsitans (gmm) ...201526313460
purification and characterization of a novel antibacterial peptide from black soldier fly (hermetia illucens) larvae.in this study, we induced and purified a novel antimicrobial peptide exhibiting activity against gram-positive bacteria from the immunized hemolymph of hermetia illucens larvae. the immunized hemolymph was extracted, and the novel defensin-like peptide 4 (dlp4) was purified using solid-phase extraction and reverse-phase chromatography. the purified dlp4 demonstrated a molecular weight of 4267 da, as determined using the matrix-assisted laser desorption/ionization-time-of-flight (maldi-tof) metho ...201525956195
efficacy of permethrin treated bed nets against leishmania major infected sand flies.insecticide treated nets (itns) are a potential tool to help control sand flies and prevent leishmaniasis. however, little is currently known about the response of leishmania infected sand flies to itns. in this study, phlebotomus duboscqi sand flies were infected with the parasite leishmania major. infected and noninfected sand flies were then evaluated against permethrin treated and untreated bed nets in a laboratory assay that required sand flies to pass through suspended netting material to ...201526276941
[study of phlebotomines sand fly wildlife suburban location of bamako (mali) presence of phlebotomus (phlebotomus) duboscqi].during three months of sampling, one thousand nine hundred and thirty five sand flies belonging to thirteen species of phlebotomine sandflies were collected in suburban location of bamako. phlebotomus duboscqi, which is the common vector of cutaneous leishmaniasis in mali, was found for the first time in bamako mostly within human houses, which can confirm the possibility of a local transmission of leishmania major. sergentomyia freetownensis was found for the first time in mali, which raises to ...201525925813
phlebotomus papatasi exposure cross-protects mice against leishmania major co-inoculated with phlebotomus duboscqi salivary gland homogenate.leishmania parasites are inoculated into host skin together with sand fly saliva and multiple exposures to uninfected sand fly bites protect mice against leishmania infection. however, sand fly vectors differ in composition of the saliva and therefore the protection elicited by their salivary proteins was shown to be species-specific. on the other hand, the optimal vaccine based on sand fly salivary proteins should be based on conserved salivary proteins conferring cross-reactivity. in the prese ...201525597641
a sand fly salivary protein vaccine shows efficacy against vector-transmitted cutaneous leishmaniasis in nonhuman primates.currently, there are no commercially available human vaccines against leishmaniasis. in rodents, cellular immunity to salivary proteins of sand fly vectors is associated to protection against leishmaniasis, making them worthy targets for further exploration as vaccines. we demonstrate that nonhuman primates (nhp) exposed to phlebotomus duboscqi uninfected sand fly bites or immunized with salivary protein pdsp15 are protected against cutaneous leishmaniasis initiated by infected bites. uninfected ...201526041707
diversity of sand flies (diptera: psychodidae: phlebotominae) in two different eco-climatic and endemic zones of cutaneous leishmaniasis in mali, west africa.being the only established vectors of the protozoan parasites of the genus leishmania, sand flies have become very important in all countries where leishmaniasis exists. to better understand the sand fly fauna, a taxonomic inventory study was carried out between january and march 2012 in soudan savannah (boundioba, sikasso) and sahelian (tieneguebougou, koulikoro) areas of mali. cdc light traps were used to collect the sand flies. collected sand flies specimens were cleaned with lacto-phenol and ...201627247347
epidemiology of the outbreak, vectors and reservoirs of cutaneous leishmaniasis in mali: a systematic review and meta-analysis.to compile available data and to estimate the burden, characteristics and risks factors of cutaneous leishmaniasis (cl) in mali.201627794393
selective factors associated with the evolution of codon usage in natural populations of arboviruses.arboviruses (arthropod borne viruses) have life cycles that include both vertebrate and invertebrate hosts with substantial differences in vector and host specificity between different viruses. most arboviruses utilize rna for their genetic material and are completely dependent on host trnas for their translation, suggesting that virus codon usage could be a target for selection. in the current study we analyzed the relative synonymous codon usage (rscu) patterns of 26 arboviruses together with ...201627455096
proceedings of the ix international symposium on phlebotomine sandflies (isops ix), reims, france, june 28th-july 1st, 2016. 201627677701
a family of csαβ defensins and defensin-like peptides from the migratory locust, locusta migratoria, and their expression dynamics during mycosis and nosemosis.insect defensins are effector components of the innate defense system. during infection, these peptides may play a role in the control of pathogens by providing protective antimicrobial barriers between epithelial cells and the hemocoel. the cdnas encoding four defensins of the migratory locust, locusta migratoria, designated lmdef 1, 3-5, were identified for the first time by transcriptome-targeted analysis. three of the members of this csαβ defensin family, lmdef 1, 3, and 5, were detected in ...201627556587
molecular phylogeny of the megadiverse insect infraorder bibionomorpha sensu lato (diptera).the phylogeny of the insect infraorder bibionomorpha (diptera) is reconstructed based on the combined analysis of three nuclear (18s, 28s, cad) and three mitochondrial (12s, 16s, coi) gene markers. all the analyses strongly support the monophyly of bibionomorpha in both the narrow (sensu stricto) and the broader (sensu lato) concepts. the major lineages of bibionomorpha sensu lato (sciaroidea, bibionoidea, anisopodoidea, and scatopsoidea) and most of the included families are supported as monoph ...201627781163
prevalence of cutaneous leishmaniasis in districts of high and low endemicity in mali.historically the western sahelian dry regions of mali are known to be highly endemic for cutaneous leishmaniasis (cl) caused by leishmania major, while cases are rarely reported from the southern savanna forest of the country. here, we report baseline prevalence of cl infection in 3 ecologically distinct districts of mali (dry sahelian, north savanna and southern savanna forest areas). we screened 195 to 250 subjects from 50 to 60 randomly selected households in each of the 6 villages (four from ...201627898671
the diversity of yellow-related proteins in sand flies (diptera: psychodidae).yellow-related proteins (yrps) present in sand fly saliva act as affinity binders of bioamines, and help the fly to complete a bloodmeal by scavenging the physiological signals of damaged cells. they are also the main antigens in sand fly saliva and their recombinant form is used as a marker of host exposure to sand flies. moreover, several salivary proteins and plasmids coding these proteins induce strong immune response in hosts bitten by sand flies and are being used to design protecting vacc ...201627812196
new "light" for one-world approach toward safe and effective control of animal diseases and insect vectors from leishmaniac perspectives.light is known to excite photosensitizers (ps) to produce cytotoxic reactive oxygen species (ros) in the presence of oxygen. this modality is attractive for designing control measures against animal diseases and pests. many ps have a proven safety record. also, the ros cytotoxicity selects no resistant mutants, unlike other drugs and pesticides. photodynamic therapy (pdt) refers to the use of ps as light activable tumoricides, microbicides and pesticides in medicine and agriculture.here we descr ...201627412129
deep sequencing-based transcriptome analysis reveals the regulatory mechanism of bemisia tabaci (hemiptera: aleyrodidae) nymph parasitized by encarsia sophia (hymenoptera: aphelinidae).the whitefly bemisia tabaci is a genetically diverse complex with multiple cryptic species, and some are the most destructive invasive pests of many ornamentals and crops worldwide. encarsia sophia is an autoparasitoid wasp that demonstrated high efficiency as bio-control agent of whiteflies. however, the immune mechanism of b. tabaci parasitization by e. sophia is unknown. in order to investigate immune response of b. tabaci to e. sophia parasitization, the transcriptome of e. sophia parasitize ...201627332546
impact of trypanosoma cruzi on antimicrobial peptide gene expression and activity in the fat body and midgut of rhodnius prolixus.rhodnius prolixus is a major vector of trypanosoma cruzi, the causative agent of chagas disease in latin america. in natural habitats, these insects are in contact with a variety of bacteria, fungi, virus and parasites that they acquire from both their environments and the blood of their hosts. microorganism ingestion may trigger the synthesis of humoral immune factors, including antimicrobial peptides (amps). the objective of this study was to compare the expression levels of amps (defensins an ...201626931761
lipophosphoglycans from leishmania amazonensis strains display immunomodulatory properties via tlr4 and do not affect sand fly infection.the immunomodulatory properties of lipophosphoglycans (lpg) from new world species of leishmania have been assessed in leishmania infantum and leishmania braziliensis, the causative agents of visceral and cutaneous leishmaniasis, respectively. this glycoconjugate is highly polymorphic among species with variation in sugars that branch off the conserved gal(β1,4)man(α1)-po4 backbone of repeat units. here, the immunomodulatory activity of lpgs from leishmania amazonensis, the causative agent of di ...201627508930
the midgut microbiota plays an essential role in sand fly vector competence for leishmania major.for many arthropod vectors, the diverse bacteria and fungi that inhabit the gut can negatively impact pathogen colonization. our attempts to exploit antibiotic treatment of colonized phlebotomus duboscqi sand flies in order to improve their vector competency for leishmania major resulted instead in flies that were refractory to the development of transmissible infections due to the inability of the parasite to survive and to colonize the anterior midgut with infective, metacyclic stage promastig ...201728580630
use of in vivo imaging system technology in leishmania major balb/c mouse ear infection studies.novel treatments for cutaneous leishmaniasis (cl) are needed, due to current lack of effective universal treatments, increasing resistance among the parasite, and toxic effects or impracticality of the current therapeutics. models of direct infection with high number of leishmania parasites in the current research of cl involving the balb/c mouse or golden syrian hamster are considered not suitable for the assessment of antileishmanial drug efficacy because of the lack of disease similarities wi ...201729253231
repellent effects of the essential oils of cymbopogon citratus and tagetes minuta on the sandfly, phlebotomus duboscqi.the sandfly, phlebotomus duboscqi is a vector of zoonotic cutaneous leishmaniasis (zcl) that is an important public health problem in eastern africa. repellents have been used for protection of humans against vectors of zcl and other vectors that transmit killer diseases including malaria, rift valley fever, dengue, and yellow fever. the repellent effects of different doses of the essential oils from the lemon grass, cymbopogon citratus and mexican marigold, tagetes minuta were evaluated in a tw ...201728202077
the transcriptome of leishmania major developmental stages in their natural sand fly vector.the life cycle of the leishmania parasite in the sand fly vector involves differentiation into several distinctive forms, each thought to represent an adaptation to specific microenvironments in the midgut of the fly. based on transcriptome sequencing (rna-seq) results, we describe the first high-resolution analysis of the transcriptome dynamics of four distinct stages of leishmania major as they develop in a natural vector, phlebotomus duboscqi the early transformation from tissue amastigotes t ...201728377524
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