Background Lutzomyia intermedia and Lutzomyia whitmani (Diptera: Psychodidae) are important and very closely related vector species of cutaneous leishmaniasis in Brazil, which are distinguishable by a few morphological differences. There is evidence of mitochondrial introgression between the two species but it is not clear whether gene flow also occurs in nuclear genes. Results We analyzed the molecular variation within the clock gene period (per) of these two species in five different localities in Eastern Brazil. AMOVA and Fst estimates showed no evidence for geographical differentiation within species. On the other hand, the values were highly significant for both analyses between species. The two species show no fixed differences and a higher number of shared polymorphisms compared to exclusive mutations. In addition, some haplotypes that are "typical" of one species were found in some individuals of the other species suggesting either the persistence of old polymorphisms or the occurrence of introgression. Two tests of gene flow, one based on linkage disequilibrium and a MCMC analysis based on coalescence, suggest that the two species might be exchanging alleles at the per locus. Conclusion Introgression might be occurring between L. intermedia and L. whitmani in period, a gene controlling behavioral rhythms in Drosophila. This result raises the question of whether similar phenomena are occurring at other loci controlling important aspects of behavior and vectorial capacity.
Mazzoni, Camila J; Souza, Nataly A; Andrade-Coelho, Claudia; Kyriacou, Charalambos P; Peixoto, Alexandre A
BACKGROUND: The phlebotomine sand flies (Diptera:Psychodidae) Lutzomyia (Nyssomyia) intermedia Lutz & Neiva 1912 and Lutzomyia (Nyssomyia) whitmani Antunes & Coutinho 1932 are two very closely related species and important vectors of American cutaneous leishmaniasis. Two single-locus studies have revealed evidence for introgression between the two species in both mitochondrial and nuclear genomes. These findings have prompted the development of a
Camila J Mazzoni; Alejandra S Araki; Gabriel EM Ferreira; Renata VDM Azevedo; Guido Barbujani; Alexandre A Peixoto
Nyssomyia intermedia (Lutz & Neiva 1912) and N. neivai (Pinto 1926) are possible vectors of tegumentary leishmaniasis in some regions of Brazil. Further, the latter was until recently, considered a junior synonym of the former. This study has the purpose of updating our knowledge of the geographical distribution of these species, based on specimens deposited at the collection of the Centro de Pesquisas René Rachou-Fiocruz, Faculdade de Saúde Pública-Universidade de São Paulo, and on data presented by literature as also to associate this distribution with the cutaneous leishmaniasis cases reported. It has been reported that N. intermedia occurs in the states of the Northeastern Region, in Rio de Janeiro, Espírito Santo, on the northern coast of São Paulo, in eastern Minas Gerais, Mato Grosso do Sul, and Goiás, close to the border with Minas Gerais and Bahia. N. neivai occurs in the Southern Region, southern coast and in western São Paulo, southern and western Minas Gerais, southern Goiás, and southern Pará, beyond Argentina, Bolivia, and Paraguay. It is important to highlight that N. intermedia and N. neivai occur in sympatry in Minas Gerais and São Paulo. N. intermedia or N. neivai are predominant or are captured abundantly in several cutaneous leishmaniasis foci in the Southeastern and Southern regions of Brazil. PMID:17612769
Andrade Filho, José Dilermando; Galati, Eunice A Bianchi; Falcão, Alda Lima
A study of the natural infection of phlebotomine sand flies by Leishmania (Viannia) was conducted in a focus of cutaneous leishmaniasis in Piçarras, on the northeastern coast of the Brazilian state of Santa Catarina. In total, 562 female Nyssomyia neivai were collected by miniature light traps near houses, separated in 61 pools and examined by PCR and Southern blot hybridization. Eight pools, four of them from the same light trap/night, were positive. This is the first finding of natural infection by Le. braziliensis of adequately identified Ny. neivai in Brazil. In this preliminary observation we observed the abundance and predominance of Ny. neivai among the captured phlebotomine species (98.5%), indicating that Ny. neivai may be the dominant vector of Leishmania in the subgenus Viannia in this area. PMID:19178921
Marcondes, Carlos Brisola; Bittencourt, Ize A; Stoco, Patricia H; Eger, Iriane; Grisard, Edmundo C; Steindel, Mário
Background The study of the distribution and ecology of sandfly species is essential for epidemiological surveillance and estimation of the transmission risk of Leishmania spp. infection. Findings In the present study, sandflies were captured in native fragmented forest areas in Rubião Júnior district, Botucatu municipality, São Paulo state, Brazil, between September 2001 and January 2005. A minimum of two automatic light traps were installed per night from 6 pm to 8 am, in different months, resulting in approximately 900 collecting hours. During this period, 216 sandfly specimens of sixteen species were captured. Pintomyia monticola and Brumptomyia guimaraesi were the most abundant with 56 specimens (25.93%) captured per species, followed by Pintomyia fischeri 28 (12.96%) and Psathyromyia pascalei 18 (8.33%). Other captured species were Lutzomyia amarali, Sciopemyia sordellii, Psathyromyia aragaoi, Nyssomyia whitmani, Migonemyia migonei, Pintomyia bianchigalatiae, Pintomyia misionensis, Brumptomyia carvalheiroi, Brumptomyia cardosoi, Brumptomyia cunhai, Brumptomyia nitzulescui, Brumptomyia brumpti and Brumptomyia spp. represented by 58 (26.85%) specimens. Conclusions Although less frequently found, the presence of Pintomyia fischeri, Nyssomyia whitmani and Migonemyia migonei, known vectors of Leishmania braziliensis, indicates risk of American cutaneous leishmaniasis occurrence. Moreover, the absence of Lutzomyia longipalpis-the main vector of Leishmania infantum chagasi, which is the agent of American visceral leishmaniasis-suggests that there is no risk of introduction and establishment of this disease in the studied area.
Over the last three decades the incidence of American cutaneous leishmaniasis (ACL) has increased sharply in Argentina and throughout the world. In the Iguazú Falls area, on the border between Brazil and Paraguay, the incidence of human ACL has risen since 2004. Most of the 36 cases of human ACL reported until 2005 have involved males over 15 years old (75%) infected during deforestation to establish individual farms. Captures carried out in primary forest, periurban areas, and deforested land sites yielded 18,438 sand flies belonging to 13 species; the most prevalent species were Lutzomyia (Nyssomyia) whitmani (87.4%) and Lutzomyia (Mygonemyia.) migonei (7.6%). Cluster analysis was used to group traps according to species and abundance of sand flies. The group of traps located in recently deforested places, in pig and chicken dwellings of houses where ACL cases had been reported in the past, and at one house with an active ACL case, had the highest abundance of Lu. whitmani and Lu. whitmani+Lu. migonei as well as the highest ratio of Lu. whitmani/Lu. migonei. Leishmania sp. infections, both in Lu. whitmani, in Lu. quinquefer, and in smears from human cases were detected by DNA kinetoplast amplification using a generic PCR protocol. The risk of ACL outbreak in the Iguazú Falls area is still associated with economic and leisure activities in primary-secondary forest, including deforestation, rural settlements, fishing, hunting, and ecotourism. In addition, the risk of periurban transmission seems likely, and this is discussed within the framework of surveillance and prevention strategies. PMID:18983809
Salomón, Oscar D; Acardi, Soraya A; Liotta, Domingo J; Fernández, María S; Lestani, Eduardo; López, Deborah; Mastrángelo, Andrea V; Figueroa, Marianela; Fattore, Gladys
Lutzomyia longipalpis (Lutz and Neiva) is a species complex of Lutzomyia pseudolon- gipalpis (Arrivillaga and Feliciangeli) and at least three other as yet undeÞned siblings. Isozyme and mitochondrial studies of allopatric populations across Central and South America have suggested the presence of four \\
J. G. C. HAMILTON; R. P. Brazil; R. Maingon
The phlebotomine sand fly Lutzomyia velezi sp.nov. was described and illustrated from male specimens collected by light trap in the Reserva Natural Cañon del Río Claro in the Central Cordillera of the Colombian Andes. The new species belongs to the series sanguinaria of the subgenus Helcocyrtomyia, which is represented in Colombia by Lutzomyia cirrita, Lutzomyia hartmanni, Lutzomyia sanguinaria, Lutzomyia scorzai, Lutzomyia sp. of Pichindé and Lutzomyia tortura. The new species can be differentiated from others of the subgenus by the combination of the following characteristics: long antennal ascoids, reaching level of the papilla, coxite with a single basal seta and fifth palpomere longer than or equal to the sum of the lengths of the third and fourth palpomeres. PMID:20512248
Bejarano, Eduar Elías; Vivero, Rafael José; Uribe, Sandra
Phlebotomines are invertebrate hosts of Leishmania genus species which are etiological agents of leishmaniases in humans and other mammals. Sandflies are often collected in entomological studies of caves both in the inner area and the adjacent environments. Caves are ecotypes clearly different from the external environment. Several caves have been opened to public visitation before any studies were performed and the places do not have scientific monitoring of the fauna, flora, geological and geographical characteristics. These events can lead to the loss of geological and biological information. Considering these aspects, this study aimed to describe the sand fly fauna, including the ecological features, in a limestone cave at the Speleological Province of Bambuí (Minas Gerais State, Brazil). A total of 8,354 specimens of sandflies belonging to 29 species were analyzed: Lutzomyia cavernicola (20%), Nyssomyia intermedia (15%), Martinsmyia oliveirai (13%), Evandromyia spelunca (12%), Evandromyia sallesi (11%), Migonemyia migonei (9%), Nyssomyia whitmani (9%), Sciopemyia sordellii (4%) and Lutzomyia longipalpis (2%). The others species represent 5% of the total. This manuscript presents data found on richness, diversity, evenness and seasonality, comparing the sand fly fauna trapped in the cave and its surroundings.
Carvalho, Gustavo Mayr de Lima; Brazil, Reginaldo Pecanha; Ramos, Mariana Campos das Neves Farah; Serra e Meira, Paula Cavalcante Lamy; Zenobio, Ana Paula Lusardo de Almeida; Botelho, Helbert Antonio; Sanguinette, Cristiani de Castilho; Saraiva, Lara; Andrade Filho, Jose Dilermando
Phlebotomines are invertebrate hosts of Leishmania genus species which are etiological agents of leishmaniases in humans and other mammals. Sandflies are often collected in entomological studies of caves both in the inner area and the adjacent environments. Caves are ecotypes clearly different from the external environment. Several caves have been opened to public visitation before any studies were performed and the places do not have scientific monitoring of the fauna, flora, geological and geographical characteristics. These events can lead to the loss of geological and biological information. Considering these aspects, this study aimed to describe the sand fly fauna, including the ecological features, in a limestone cave at the Speleological Province of Bambuí (Minas Gerais State, Brazil). A total of 8,354 specimens of sandflies belonging to 29 species were analyzed: Lutzomyia cavernicola (20%), Nyssomyia intermedia (15%), Martinsmyia oliveirai (13%), Evandromyia spelunca (12%), Evandromyia sallesi (11%), Migonemyia migonei (9%), Nyssomyia whitmani (9%), Sciopemyia sordellii (4%) and Lutzomyia longipalpis (2%). The others species represent 5% of the total. This manuscript presents data found on richness, diversity, evenness and seasonality, comparing the sand fly fauna trapped in the cave and its surroundings. PMID:24130847
Carvalho, Gustavo Mayr de Lima; Brazil, Reginaldo Peçanha; Ramos, Mariana Campos das Neves Farah; Serra E Meira, Paula Cavalcante Lamy; Zenóbio, Ana Paula Lusardo de Almeida; Botelho, Helbert Antônio; Sanguinette, Cristiani de Castilho; Saraiva, Lara; Andrade Filho, José Dilermando
Evolutionary theory predicts that virulence of parasites for mobile vector insects will be low for natural parasite-host associations that have coevolved. I determined virulence of the malaria parasite of lizards, Plasmodium mexicanum, for its vectors, two species of sand fly (Diptera: Psychodidae), Lutzomyia vexator (Coquillett 1907) and Lutzomyia stewarti (Mangabeira Fo & Galindo 1944), by measuring several life history traits. Developmental rate from egg to eclosion differed for the two species when noninfected. For both sand fly species, developmental rate for each stage (egg to larval hatching, larval period, pupal period) and life span were not altered by infection. Infected sand flies, however, produced fewer eggs. This reduction in fecundity may be a result of lower quality of the blood meal taken from infected lizards (lower concentration of hemoglobin). This report is the first measure of virulence of Plasmodium for an insect vector other than a mosquito and concords with both expectations of theory and previous studies on natural parasite-host associations that revealed low virulence. PMID:22238877
Schall, Jos J
Lutzomyia longipalpis is the principal species of phlebotomine incriminated as vector of Leishmania infantum, the etiological agent of visceral leishmaniasis in the Americas. Despite its importance as vector, almost nothing related to the larval biology, especially about its digestive system has been published. The objective of the present study was to obtain an overview of carbohydrate digestion by the larvae. Taking in account that phlebotomine larvae live in the soil rich in decaying materials and microorganisms we searched principally for enzymes capable to hydrolyze carbohydrates present in this kind of substrate. The principal carbohydrases encountered in the midgut were partially characterized. One of them is a ?-amylase present in the anterior midgut. It is probably involved with the digestion of glycogen, the reserve carbohydrate of fungi. Two other especially active enzymes were present in the posterior midgut, a membrane bound ?-glucosidase and a membrane bound trehalase. The first, complete the digestion of glycogen and the other probably acts in the digestion of trehalose, a carbohydrate usually encountered in microorganisms undergoing hydric stress. In a screening done with the use of p-nitrophenyl-derived substrates other less active enzymes were also observed in the midgut. A general view of carbohydrate digestion in L. longipalpis was presented. Our results indicate that soil microorganisms appear to be the main source of nutrients for the larvae. PMID:22841889
Vale, Vladimir F; Moreira, Bruno H; Moraes, Caroline S; Pereira, Marcos H; Genta, Fernando A; Gontijo, Nelder F
Sand flies in the Lutzomyia longipalpis species complex include the primary vector of Leishmania chagasi, the etiologic agent of visceral leishmaniasis in the Neotropics. Twelve L. longipalpis populations from South and Central America were compared using the cytochrome c oxidase I (COI) gene from the mitochondrial genome. The haplotype profiles for each population revealed that the majority of sequence variation
J. C. Arrivillaga; D. E. Norris; M. D. Feliciangeli; G. C. Lanzaro
Genes involved in the reproductive isolation are particularly useful as molecular markers in speciation studies. Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae), a putative species complex, is a vector of visceral leishmaniasis in Latin America. We isolated from this species a fragment homologous to cacophony, a Drosophila gene that encodes features of the lovesong, an acoustic signal that is important in the
M. Bottecchia; S. G. Oliveira; L. G. S. R. Bauzer; N. A. Souza; R. D. Ward; K. J. Garner; C. P. Kyriacou; A. A. Peixoto
BACKGROUND: Current strategies for controlling American visceral leishmaniasis (AVL) have been unable to prevent the spread of the disease across Brazil. With no effective vaccine and culling of infected dogs an unpopular and unsuccessful alternative, new tools are urgently needed to manage populations of the sand fly vector, Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae). Here, we test two potential
Daniel P Bray; Graziella B Alves; Maria E Dorval; Reginaldo P Brazil
Phlebotomine sand flies are vectors of bacteria, parasites, and viruses. In the western USA a sand fly, Lutzomyia apache Young and Perkins, was initially associated with epizootics of vesicular stomatitis virus (VSV), because sand flies were trapped at sites of an outbreak. Additional studies indica...
Visceral leishmaniasis is an endemic protozoal disease of humans and dogs in tropical and subtropical regions in Asia, Africa, southern Europe, Central America, and South America, where sand ßies (genera Phlebotomus and Lutzomyia) act as vectors. An outbreak in a New York foxhound kennel and subsequent surveillance revealed widespread Leishmania infantum infection of dogs in the United States, outside the
Richard S. Ostfeld; Pamela Roy; Wendy Haumaier; Lauren Canter; Felicia Keesing; Edgar D. Rowton
Lutzomyia antunesi has been commonly reported in outbreaks of cutaneous leishmaniasis (CL) in the Orinoquia region of Colombia. The bionomics of this species were studied in the municipality of Villavicencio (Meta, Colombia). Sandflies were captured over the course of one week per month for one year in intradomiciliary, peridomiciliary and extradomiciliary housing areas. The captures were performed from 06:00 pm-06:00 am using CDC light traps and the females were processed for polymerase chain reaction (PCR) to detect Leishmania spp. A total of 22,097 specimens and 19 species were captured of which Lu. antunesi (89%) and Lutzomyia walkeri (5%) were the most abundant. Other species recognised as anthropophilic (Lutzomyia panamensis, Lutzomyia gomezi, Lutzomyia flaviscutellata and Lutzomyia fairtigi) were present in very low abundance (< 2%). Natural infection with Leishmania spp was detected using PCR in Lu. antunesi, Lu. panamensis and Lu. flavicutellata, showing infection rates of 1%, 4.8% and 7.5%, respectively. The present paper provides information on various ecological aspects of Lu. antunesi. An analysis of seasonality shows that this species increases in abundance in the hottest months (December, January and February), directly correlating with the maximum temperature and inversely correlating with precipitation. The natural infection rate is associated with the peaks of highest abundance. PMID:23828011
Vásquez Trujillo, Adolfo; González Reina, Angélica E; Góngora Orjuela, Agustín; Prieto Suárez, Edgar; Palomares, Jairo Enrique; Buitrago Alvarez, Luz Stella
Male Lutzomyia longipalpis produce terpene sex pheromones in glandular tissue underlying the cuticle. The pheromones are transmitted to the surface via cuticle-lined ducts (measuring 0.25 microm in diameter), each of which reaches the surface in the centre of a papule (measuring 3-3.5 microm in diameter). Similar papules, in a range of shapes but all characterized by the presence of a central pore and absence of macroserae, occur in some other species of sandfly. The aim of the present study was to determine the distribution of sex pheromones in sandflies of the genus Lutzomyia that do and do not have the papules. The results indicate that sex pheromones are not widely distributed amongst male Lutzomyia spp. Male members of the genus can be subdivided into three groups: those that produce terpenes and have cuticular papules; those that do not produce terpenes but still have the associated papules; and those that have neither terpenes nor papules. The papules seen in the species that do not synthesise sex pheromones are presumably vestigial, non-functional structures. Such species may have stopped producing pheromone as the result of changes in the way in which the females found and selected mates or changing feeding preferences. A similar event has occurred in the Lepidoptera, where vestigial pheromone-secreting structures remain in some species which no longer produce pheromone. Lutzomyia lenti collected in southern Brazil produced a novel diterpene whereas male L. lenti from north-eastern Brazil did not, supporting suggestions by others that L. lenti is, like L. longipalpis, a species complex. PMID:11989537
Hamilton, J G C; Brazil, R P; Campbell-Lendrum, D; Davies, C R; Kelly, D W; Pessoa, F A C; de Queiroz, R G
The saliva of the sand fly Lutzomyia longipalpis, a major vector of Leishmania, exhibits pharmacological and immunomodulatory activities that may facilitate entry and establishment of parasites into the\\u000a vertebrate host. Salivary gland components of the sand fly are, therefore, potential candidates in the development of a vaccine\\u000a against human leishmaniasis. With the objective of identifying sand fly saliva proteins that
Diana Bahia; Nelder Figueiredo Gontijo; Ileana Rodríguez León; Jonas Perales; Marcos Horácio Pereira; Guilherme Oliveira; Rodrigo Corrêa-Oliveira; Alexandre Barbosa Reis
Visceral leishmaniasis is a major public health issue in South America, where the disease is rapidly spreading. Changes in ecology and distribution of the principal vector, Lutzomyia longipalpis are among the factors accounting for the increasing incidence of the disease in this region. However, information about the ecology of L. longipalpis is still incipient, which may directly impair the implementation of effective control programs. Herein, the ecology of L. longipalpis was studied in a focus of visceral leishmaniasis in north-eastern Brazil. From August 2009 to August 2010, phlebotomine sand flies were monthly collected in four localities using CDC light traps (~37 per month) and a lantern-baited Shannon trap with mouth aspirators. A total of 24,226 phlebotomine sand flies were collected with light traps and 375 with mouth aspirators. The most abundant species was L. longipalpis, representing 97.9% of the specimens collected with light traps and 91.5% with the mouth aspirator. Other species (Lutzomyia evandroi, Lutzomyia lenti and Lutzomyia sallesi) were found in low numbers. Most phlebotomine sand flies (94.6%) were collected at chicken coops and corrals. No significant correlation was found between the monthly abundance of phlebotomine sand flies and the monthly averages of temperature, relative humidity or rainfall. However, interestingly enough, 82.4% of L. longipalpis specimens were collected in months when relative humidity surpassed 75%. This study points out that this vector is well adapted to live in different habitats and to different climate conditions. It also suggests that some north-eastern populations of L. longipalpis may be more xerotolerant than southern populations. Further studies to assess the relationship between microclimate and L. longipalpis density in different Brazilian regions are advised. PMID:23369878
Costa, Pietra Lemos; Dantas-Torres, Filipe; da Silva, Fernando José; Guimarães, Vanessa Cristina Fitipaldi Veloso; Gaudêncio, Kamila; Brandão-Filho, Sinval Pinto
Phlebotomine sand flies are vectors of Leishmania that are acquired by the female sand fly during blood feeding on an infected mammal. Leishmania parasites develop exclusively in the gut lumen during their residence in the insect before transmission to a suitable host during the next blood feed. Female phlebotomine sand flies are blood feeding insects but their life style of visiting plants as well as animals, and the propensity for larvae to feed on detritus including animal faeces means that the insect host and parasite are exposed to a range of microorganisms. Thus, the sand fly microbiota may interact with the developing Leishmania population in the gut. The aim of the study was to investigate and identify the bacterial diversity associated with wild adult female Lutzomyia sand flies from different geographical locations in the New World. The bacterial phylotypes recovered from 16S rRNA gene clone libraries obtained from wild caught adult female Lutzomyia sand flies were estimated from direct band sequencing after denaturing gradient gel electrophoresis of bacterial 16 rRNA gene fragments. These results confirm that the Lutzomyia sand flies contain a limited array of bacterial phylotypes across several divisions. Several potential plant-related bacterial sequences were detected including Erwinia sp. and putative Ralstonia sp. from two sand fly species sampled from 3 geographically separated regions in Brazil. Identification of putative human pathogens also demonstrated the potential for sand flies to act as vectors of bacterial pathogens of medical importance in addition to their role in Leishmania transmission. PMID:22880020
Sant'Anna, Mauricio R V; Darby, Alistair C; Brazil, Reginaldo P; Montoya-Lerma, James; Dillon, Viv M; Bates, Paul A; Dillon, Rod J
Sand flies Lutzomyia (Psathyromyia) shannoni (Dyar) and Lu. (Helcocyrtomyia) vexator (Coquillet) were collected for the first time in southwest Missouri and southeast Kansas, expanding the known range of these species in North America. Altogether, 680 sand flies (356 males and 324 females) were collected during trapping from May through October 2011 and identified using morphological characters. Of the total sand flies collected 315 were identified as Lu. shannoni, with 181 individuals (or 26.6% of all sand flies) trapped in Missouri and 134 individuals (or 19.7%) trapped in Kansas. Whereas 358 Lu. vexator were identified from SW MO, only a single specimen was trapped in SE KS. One male Lu. vexator with asymmetric gonostyli was trapped in Missouri. We also developed a PCR protocol to consistently and accurately distinguish Lu. shannoni from Lu. vexator based on presence or absence of a 416bp fragment from the cytochrome oxidase I gene.
Weng, Ju-Lin; Young, Samantha L; Gordon, David M; Claborn, David; Petersen, Christine; Ramalho-Ortigao, Marcelo
Natural infection of sand flies with Leishmania parasites was surveyed in an Amazonian area in Ecuador where leishmaniasis is endemic. Seventy-one female sand flies were dissected and one was positive for Leishmania protozoa. The species of this sand fly was identified as Lutzomyia (Lu.) tortura on the basis of morphologic characteristics. Analysis of the cytochrome b gene sequence identified the parasite as L. (Viannia) naiffi. We report the distribution of L. (V.) naiffi in Ecuador and detection of a naturally infected sand fly in the Ecuadorian Amazon and natural infection of Lu. tortura with Leishmania parasites in the New World. PMID:18784239
Kato, Hirotomo; Gomez, Eduardo A; Yamamoto, Yu-ichi; Calvopiña, Manuel; Guevara, Angel G; Marco, Jorge D; Barroso, Paola A; Iwata, Hiroyuki; Hashiguchi, Yoshihisa
Phlebotomine captures were performed during 2004 in Clorinda, Argentina. Clorinda is located across the branches of the Paraguay river in front of Asunción city, Paraguay. Reports of canine and human visceral leishmaniasis in Asunción have been increasing since 1997, however neither leishmaniasis cases nor sand flies were ever recorded from Clorinda. Light traps were located in migration paths (bridges, port), and peridomestic environments of Clorinda and surrounding localities. Lutzomyia longipalpis was found in Clorinda and Puerto Pilcomayo, first report in a potential visceral leishmaniasis transmission area for Argentina. Active surveillance is required immediately in the localities involved and the surrounding area. PMID:16184223
Salomón, Oscar D; Orellano, Pablo W
The female of the phlebotomine sand fly Lutzomyia reclusa Fernández & Rogers 1991 [= Pintomyia (Pifanomyia) reclusa (Fernández & Rogers) sensu Galati], is described for the first time, based on specimens collected in the Department of Cajamarca, in northern Peru. The female can be recognized from other species of the series pia, species group Verrucarum, by wing venation with beta shorter than half of alpha, labrum just shorter than head width but longer than flagellomere 1, palpomere 5 much longer than palpomere 3, arrangement of cibarial armature, and form of spermathecae and relative size of spermathecal ducts. Diagnostic characters and measurements of the male of Lu. reclusa are provided as well. PMID:21485349
Ibáñez-Bernal, Sergio; Cáceres, Abraham G
Rift Valley fever virus was shown to replicate in Lutzomyia longipalpis after intrathoracic inoculation. Viral titers peaked at approximately 4 days postinoculation [mean titer = 10(4.0) plaque forming units (PFU)] and remained relatively constant through day 7. A minimum of 6 of 326 sand flies transmitted virus by bite to susceptible hamsters after 5-9 days of extrinsic incubation. Viral titers of sand flies exposed per os declined steadily through day 9. None of 378 flies that had ingested approximately 10(4.0) PFU of virus transmitted virus when refed on susceptible hamsters. PMID:6711746
Hoch, A L; Turell, M J; Bailey, C L
The growth of Rio Grande (RG) virus, the only phlebovirus known to occur in the United States, was studied in Lutzomyia anthophora, its suspected sand fly vector. RG viral titers in infected flies increased more than 10,000-fold within 7 days after intrathoracic inoculation. Experimentally infected female L. anthophora transmitted virus transovarially (vertically) to 54.8% of their F1 progeny. This is the first virologically confirmed demonstration of transovarial transmission of a phlebovirus by sand flies. It indicates one mechanism by which RG and possibly other phleboviruses may be maintained in nature. PMID:6683943
Endris, R G; Tesh, R B; Young, D G
Natural infection of sand flies with Leishmania parasites was surveyed in an Amazonian area in Ecuador where leishmaniasis is endemic. Seventy-one female sand flies were dissected and one was positive for Leishmania protozoa. The species of this sand fly was identified as Lutzomyia (Lu.) tortura on the basis of morphologic character- istics. Analysis of the cytochrome b gene sequence identified
Hirotomo Kato; Eduardo A. Gomez; Yu-ichi Yamamoto; Manuel Calvopiña; Angel G. Guevara; Jorge D. Marco; Paola A. Barroso; Hiroyuki Iwata; Yoshihisa Hashiguchi
A BSTRACT. A dichotomous key for the identification of the females of the up to date known species of M exican Phlebotominae (Diptera: Psychodidae) of the genus Lutzomyia França is presented. The characteristics used in the key are adequatelly illustrated to facilitate its use. K EY WORDS: Diptera, Psychodidae, Phlebotominae, M exico, taxonomy, identification, key, fem ales.
A group of 18 research workers involved in different aspects of the biology of Lutzomyia longipalpis discussed whether or not it is important to give taxonomically valid names to populations that have been defined by biological, biochemical and molecular methods to be reproductively isolated. The type material of this medically important species has been lost and because of this it was recommended that a colony should be established from insects captured in the region of the type area and that their description should serve as the basis for future descriptions. It was pointed out that there is a lack of uniformity in the naming of closely related American sand flies and that some of the differences between populations of Lu. longipalpis are greater than those between accepted species. The majority of the participants agreed that the populations that have been defined in the literature as sibling species should be named. PMID:20140386
Brandão-Filho, Sinval P; Balbino, Valdir Q; Marcondes, Carlos B; Brazil, Reginaldo P; Hamilton, James G; Shaw, Jeffrey J
We analyzed the development of Leishmania (Leishmania) infantum chagasi in its natural sandfly vector Lutzomyia longipalpis. In addition, we compared sandfly infections initiated with axenic amastigotes or promastigotes. Our data showed no important difference between Lu. longipalpis infection rates resulting from either type of infections. Furthermore, development of infection was equivalent in both cases. All promastigote forms were found inside the sandfly and, after blood digestion, most of the population consisted of procyclics and nectomonads. A low percentage of metacyclic forms was coincident with a high number of nectomonads during late stages of infection, but which form gives rise to metacyclic forms in L. infantum chagasi is unknown. These results also show that the promastigote infection model, at least for this situation, is suitable for obtaining of infected sandflies because it is easier and less laborious. PMID:22492144
Freitas, Vanessa C; Parreiras, Klívia P; Duarte, Ana Paula M; Secundino, Nágila F C; Pimenta, Paulo F P
Laboratory-reared female sand flies (Lutzomyia shannoni) were experimentally infected, orally and by intrathoracic inoculation, with the New Jersey serotype of vesicular stomatitis (VSNJ) virus. Virus replication occurred in the insects following infection by both routes. Virus titers greater than 10(4) plaque forming units of VSNJ virus were present in heads of orally infected sand flies 12 days after virus ingestion, confirming that a persistent disseminated infection had occurred. Both orally and parenterally infected Lu. shannoni transmitted VSNJ virus by bite to susceptible rodents and by transovarial transmission to a small percentage of their F1 progeny. The significance of these findings in the epizootiology of VSNJ virus on Ossabaw Island, Georgia, an enzootic focus of this virus, is discussed. PMID:2160198
Comer, J A; Tesh, R B; Modi, G B; Corn, J L; Nettles, V F
The saliva of blood-sucking arthropods contains powerful pharmacologically active substances and may be a vaccine target against some vector-borne diseases. Subtractive cloning combined with biochemical approaches was used to discover activities in the salivary glands of the hematophagous fly Lutzomyia longipalpis. Sequences of nine full-length cDNA clones were obtained, five of which are possibly associated with blood-meal acquisition, each having
Rosane Charlab; Jesus G. Valenzuela; Edgar D. Rowton; Jose M. C. Ribeiro
Studies were undertaken on the phlebotomines in the municipalities of Bujari, Xapuri and Rio Branco in the state of Acre. The abundance of species on the ground and in the tree canopy was estimated by Standardized Index of Species Abundance. Of the 52 species identified, Lutzomyia (N.) antunesi, Lutzomyia (N.) whitmani, Lutzomyia (P.) davisi, Lutzomyia migonei, Lutzomyia (N.) umbratilis, Lutzomyia (N.) flaviscutellata, Lutzomyia (T.) ubiqui-talis, Lutzomyia (P.) hirsuta hirsuta, Lutzomyia (P.) paraensis and Lutzomyia (P.) ayrozai are known to be vectors of Leishmania, the causative agent of American cutaneous leishmaniasis. Lutzomyia (T.) auraensis, Lu. (N.) antunesi, Lu. (N.) whitmani and Lu. (P.) davisi accounted for 66.95% of the specimens collected. Lu. (N.) whitmani was the most abundant species, followed by Lu. (N.) antunesi and Lu. (P.) davisi. Lu. (N.) antunesi was the most abundant species in the soil as well as in the canopy. Lu. (N.) umbratilis occurred in all three municipalities and was the fifth most abundant species in the Chico Mendes Municipal Park in Rio Branco. It was collected on both the ground level as well as in the canopy; however, it was more frequently collected in the tree canopy. The present study suggests the existence of three transmission cycles of Leishmania in Acre, including the transmission of Leishmania (V.) guyanensis by Lu. (N.) umbratilis south of the Amazon River. PMID:19148413
Azevedo, Alfredo C R; Costa, Simone M; Pinto, Maria C G; Souza, Janis L; Cruz, Henrique C; Vidal, Joaquim; Rangel, Elizabeth F
The aims of this study were to carry out a serological survey of canine leishmaniasis and identify the phlebotomine fauna in the urban area of Bonito, Mato Grosso do Sul. The serological survey was conducted on a sample of 303 dogs, by means of the indirect immunofluorescence test. Phlebotomines were captured using automated light traps. The serological survey found that 30% of the dogs were seropositive, both from the center and from all districts of the town. A total of 2,772 specimens of phlebotomines were caught and the species most found was Lutzomyia longipalpis (90.4%), which corroborated its role as the vector of for canine visceral leishmaniasis in the region. Phlebotomines of the species Bichromomyia flaviscutellata (the main vector for Leishmania (Leishmania) amazonensis) and Nyssomyia whitmani (the vector for Leishmania (Viannia) brasiliensis) were also caught. The findings indicate the need for continuous epidemiological surveillance, with attention towards diminishing the vector breeding sites and the transmission of these diseases in that region. PMID:19967228
Andrade, Ana Rachel Oliveira de; Nunes, Vânia Lúcia Brandão; Galati, Eunice Aparecida Bianchi; de Arruda, Carla Cardozo Pinto; Santos, Mirella Ferreira da Cunha; Rocca, Maria Elizabeth Gizi; Aquino, Ricardo Braga
Population dynamics of Lutzomyia shannoni were monitored from April 1986 through December 1987 on Ossabaw Island, Ga. Most (99%) of the 19,788 adult sand flies were collected in light traps supplemented with dry ice; less than or equal to 1% were aspirated from diurnal resting sites. Adult sand flies first appeared in April and were followed by peaks of abundance during May 1986, and May and July 1987. Numbers of adults captured fell rapidly in October and November 1986 and in September and October 1987. No specimens were collected in December 1986 or in March, November, and December 1987. Light trap catch was affected positively by mean nightly air temperature and negatively by rainfall 14 d before collection, but not by wind speed or moon phase. Vesicular stomatitis viral activity, as measured by antibodies in feral and domestic swine, roughly corresponded to the seasonal appearance of adult L. shannoni during 1986 and 1987. Significantly more adults (72%) were collected in light traps at ground level (0.5m) than at heights of 4 and 8m. Most resting adults were collected from dark, moist tree holes and cavities of various hardwoods. PMID:1495026
Brinson, F J; Hagan, D V; Comer, J A; Strohlein, D A
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 antibiotics to adult female L. longipalpis resulted in an up-regulation of caspar expression relative to controls. caspar was differentially expressed when females were fed on Gram-negative and Gram-positive bacterial species. caspar expression was significantly down-regulated in females between 3 and 6 days after a blood feed containing Leishmania mexicana amastigotes. RNA interference was used to deplete caspar expression in female L. longipalpis, which were subsequently fed with Leishmania in a blood meal. Sand fly gut populations of both L. mexicana and L. infantum were significantly reduced in caspar-depleted females. The prevalence of L. infantum infection in the females fell from 85 to 45%. Our results provide the first insight into the operation of immune homeostasis in phlebotomine sand flies during the growth of bacterial and Leishmania populations in the digestive tract. We have demonstrated that the activation of the sand fly immune system, via depletion of a single gene, can lead to the abortion of Leishmania development and the disruption of transmission by the phlebotomine sand fly.
Telleria, Erich L.; Sant'Anna, Mauricio R. V.; Ortigao-Farias, Joao R.; Pitaluga, Andre N.; Dillon, Viv M.; Bates, Paul A.; Traub-Cseko, Yara M.; Dillon, Rod J.
The chemical composition of essential oils from three species of plants belonging to the Eucalyptus genus was determined and, their insecticidal effects on egg, larva and adult phases of Lutzomyia longipalpis were assessed. The insects were collected in the municipality of Sobral in the State of Ceará, Brazil. Five treatments with different concentrations were performed along with two negative controls, distilled water and Tween 80 (3%), and a positive control, cypermethrin (0.196mg/ml). The tests were carried out in plastic pots internally coated with sterile plaster and filled with a substrate made of rabbit feces and crushed cassava leaves. The eggs, larvae and adults were sprayed with the oils. The hatched larvae were counted for 10 consecutive days and observed until pupation. Insect mortality was observed after 24, 48 and 72h. E. staigeriana oil was the most effective on all three phases of the insect, followed by E. citriodora and E. globulus oils, respectively. The major constituents of the oils were Z-citral and alpha-citral (E. staigeriana), citronellal (E. citriodora) and 1,8-cineole (E. globulus). The Eucalyptus essential oils constitute alternative natural products for the control of L. longipalpis since the median effective concentration (EC(50)) values revealed relevant action as compared with other natural products, some of their chemical constituents are already known for their insecticidal activity and these oils are produced in commercial scale in Brazil. PMID:19896276
Maciel, M V; Morais, S M; Bevilaqua, C M L; Silva, R A; Barros, R S; Sousa, R N; Sousa, L C; Brito, E S; Souza-Neto, M A
Lutzomyia longipalpis is the main vector of visceral leishmaniasis in Brazil. The objective was to evaluate the effect of oil from (Azadirachta indica) neem seeds on eggs, larvae and adults of the vector. The insects were captured in the field and kept in the laboratory at +/- 27 °C and 80% relative humidity. Five treatments with different concentrations were performed using two negative controls (distilled water and Tween 80) and a positive control. The eggs were sprayed with the oil at different concentrations and the number of hatched larvae evaluated for 10 days. Mortality of larvae was observed to pupation and adult mortality was observed after 24, 48, and 72 hours. Statistical analysis was performed by Tukey test at 5% probability. The highest oil concentration of eggs obtained 65.16 +/- 3.24% efficacy for reducing egg hatching. The test with larvae showed 67.75 +/- 2.21% efficacy at a concentration of 100 mg.mL?¹. In adults, the efficacy of the 100 mg.mL?¹ concentration was 96.64 +/- 4.11% after 24 hours. The phytochemical analysis revealed the presence of triterpenes. These results demonstrate the potential use of this oil in the control of this vector. PMID:20385053
Maciel, Michelline V; Morais, Selene M; Bevilaqua, Claudia M L; Silva, Rafaella A; Barros, Renata S; Sousa, Raimundo N; Sousa, Lindemberg C; Machado, Lyeghyna K A; Brito, Edy S; Souza-Neto, Manoel A
Lutzomyia vexator is an efficient experimental vector of Plasmodium mexicanum, infecting 69.2% (9/13) of the Sceloporus undulatus lizards with as few as one bite. Sporozoites were present in the salivary glands by day 6.5 postfeed and infective by day 8 postfeed at 27 degrees C. The prepatent period was relatively long, ranging from 23 to 40 days for bite-induced infections and appears to be related to the number of sporozoites injected. The acute phase of the infection is initially exponential and rapid. All lizards (6) that were not sacrificed, died of fulminating infections from 13 to 56 days after parasites were seen in the blood films. Gametocytes from 2 experimentally infected lizards were infective to L. vexator during the course of the acute infection. The majority of P. mexicanum parasites were in erythrocytes of Sc. undulatus. Exoerythrocytic forms were observed in circulating lymphocytes and thrombocytes, lymphocytes of spleen and bone marrow, and endothelial cells of brain capillaries. PMID:3504905
Klein, T A; Young, D G; Telford, S R; Kimsey, R
It was recently shown that immunization of hamsters with DNA plasmids coding LJM19, a sand fly salivary protein, partially protected against a challenge with Leishmania chagasi, whereas immunization with KMP11 DNA plasmid, a Leishmania antigen, induced protection against L. donovani infection. In the present study, we evaluated the protective effect of immunization with both LJM19 and KMP11 DNA plasmid together. Concerning the protection against an infection by L. chagasi, immunization with DNA plasmids coding LJM19 or KMP11, as well as with both plasmids combined, induced IFN-? production in draining lymph nodes at 7, 14 and 21 days post-immunization. Immunized hamsters challenged with L. chagasi plus Salivary Gland Sonicate (SGS) from Lutzomyia longipalpis showed an enhancement of IFN-?/IL-10 and IFN-?/TGF-? in draining lymph nodes after 7 and 14 days of infection. Two and five months after challenge, immunized animals showed reduced parasite load in the liver and spleen, as well as increased IFN-?/IL-10 and IFN-?/TGF-? ratios in the spleen. Furthermore, immunized animals remained with a normal hematological profile even five months after the challenge, whereas L. chagasi in unimmunized hamsters lead to a significant anemia. The protection observed with LJM19 or KMP11 DNA plasmids used alone was very similar to the protection obtained by the combination of both plasmids. PMID:21875567
da Silva, Robson A A; Tavares, Natália M; Costa, Dirceu; Pitombo, Maiana; Barbosa, Larissa; Fukutani, Kyioshi; Miranda, Jose C; de Oliveira, Camila I; Valenzuela, Jesus G; Barral, Aldina; Soto, Manuel; Barral-Netto, Manoel; Brodskyn, Cláudia
Lutzomyia longipalpis is the primary vector of the parasite responsible for visceral leishmaniasis in the Americas. In the present study, Lu. longipalpis was found in a domiciliary area in Limón, a district in Capira, a region in which cutaneous leishmaniasis is endemic in Panama. Previously, this species has been found in a humid forest in this same region. Finding Lu. longipalpis in domiciliary areas indicates that this species may be adapting to new habitats and that it may play a role in the transmission of leishmaniasis in Panama. PMID:22241132
Valderrama, Anayansi; Tavares, Mara Garcia; Andrade Filho, José Dilermando
We dissected the digestive tract of 245 females in pools of 35 flies forming 7 groups. These flies were Lutzomyia longipalpis originating from Lapinha Cave, Lagoa Santa, Minas Gerais. Out of the 8 species of bacteria isolated there was a predominancy of Gram negative bacterias (GNB) in the group of non-fermenters of sugar belonging to the following species: Acinetobacter lwoffii, Stenotrophomonas maltophilia, Pseudomonas putida and Flavimonas orizihabitans. The group of GNB fermenters were: Enterobacter cloacae and Klebsiella ozaenae. In the Gram positive group we isolated the genera Bacillus thuringiensis and Staphylococcus spp. PMID:10967602
Oliveira, S M; Moraes, B A; Gonçalves, C A; Giordano-Dias, C M; D'Almeida, J M; Asensi, M D; Mello, R P; Brazil, R P
In Brazil, four populations of Lutzomyia longipalpis each producing different sex pheromones are recognised. It has been suggested that these chemotype populations represent true sibling species. In this study we present the results of an analysis, by coupled gas chromatography-mass spectrometry, of the pheromones of males L. longipalpis from two different municipalities of the state of São Paulo. Our study showed that L. longipalpis from these two municipalities produced different sex pheromones from each other. This coupled with the remarkable difference between the epidemiological situation in Araçatuba and Espírito Santo do Pinhal, suggests that the (S)-9-methylgermacrene-B and cembrene-1 populations may have different vectorial capacities. PMID:16699721
Casanova, Cláudio; Hamilton, J G C; Trigo, J R; Costa, Antonio I P
Leishmaniasis is a public health problem that has been increasing year by year, with the further difficulty that an efficient control system is not available. Therefore, it is necessary to search for less contaminating and dangerous alternatives for controlling Leishmania transmitting sandflies. The purpose of this study was to evaluate the activity of Monticalia greenmaniana (Asteraceae) extracts and essential oil as an adulticide against Lutzomyia migonei (Diptera: Psychodidae) females, from a laboratory colony, in experimental conditions. Dry aerial parts of M. greenmaniana (Hieron) Jeffrey were used. Methanolic and aqueous extracts were prepared, and essential oil was obtained by hydrodistillation. Adulticide tests in pots, adulticide tests in cages, and knocked-down effects were determined. The results obtained demonstrated that methanolic and aqueous extracts produced adulticide activity. The essential oil from M. greenmaniana was proved to be the most toxic against L. migonei, with a 95 % death rate at a concentration of 0.01 mg/ml during a 1-h exposure. The essential oil showed a DL50?=?0.0050 and DL98?=?0.0066 mg/ml. The methanolic extract was DL50?=?0.130 and DL98?=?1.016 mg/ml, and the aqueous extract, DL50?=?0.487 and DL98 10.924 mg/ml. The knocked-down effect for the M. greenmaniana oil showed a KDTL50?=?48.6 and KDTL98?=?90.1 min. It was concluded that the essential oil from M. greenmaniana showed a strong insecticide effect against L. migonei females, which encourages us to continue these studies in search for control alternatives against sandflies. PMID:22476600
Cárdenas, José; Rojas, Janne; Rondón, Maritza; Nieves, Elsa
Leishmaniasis is a vector-borne disease with a complex epidemiology and ecology. Visceral leishmaniasis (VL) is its most severe clinical form as it results in death if not treated. In Latin America VL is caused by the protist parasite Leishmania infantum (syn. chagasi) and transmitted by Lutzomyia longipalpis. This phlebotomine sand fly is only found in the New World, from Mexico to Argentina. However, due to deforestation, migration and urbanisation, among others, VL in Latin America is undergoing an evident geographic expansion as well as dramatic changes in its transmission patterns. In this context, the first VL outbreak was recently reported in Argentina, which has already caused 7 deaths and 83 reported cases. Insect vector transcriptomic analyses enable the identification of molecules involved in the insect's biology and vector-parasite interaction. Previous studies on laboratory reared Lu. longipalpis have provided a descriptive repertoire of gene expression in the whole insect, midgut, salivary gland and male reproductive organs. Nevertheless, the study of wild specimens would contribute a unique insight into the development of novel bioinsecticides. Given the recent VL outbreak in Argentina and the compelling need to develop appropriate control strategies, this study focused on wild male and female Lu. longipalpis from an Argentine endemic (Posadas, Misiones) and a Brazilian non-endemic (Lapinha Cave, Minas Gerais) VL location. In this study, total RNA was extracted from the sand flies, submitted to sequence independent amplification and high-throughput pyrosequencing. This is the first time an unbiased and comprehensive transcriptomic approach has been used to analyse an infectious disease vector in its natural environment. Transcripts identified in the sand flies showed characteristic profiles which correlated with the environment of origin and with taxa previously identified in these same specimens. Among these, various genes represented putative targets for vector control via RNA interference (RNAi).
McCarthy, Christina B.; Santini, Maria Soledad; Pimenta, Paulo F. P.; Diambra, Luis A.
Leishmaniasis is a vector-borne disease with a complex epidemiology and ecology. Visceral leishmaniasis (VL) is its most severe clinical form as it results in death if not treated. In Latin America VL is caused by the protist parasite Leishmania infantum (syn. chagasi) and transmitted by Lutzomyia longipalpis. This phlebotomine sand fly is only found in the New World, from Mexico to Argentina. However, due to deforestation, migration and urbanisation, among others, VL in Latin America is undergoing an evident geographic expansion as well as dramatic changes in its transmission patterns. In this context, the first VL outbreak was recently reported in Argentina, which has already caused 7 deaths and 83 reported cases. Insect vector transcriptomic analyses enable the identification of molecules involved in the insect's biology and vector-parasite interaction. Previous studies on laboratory reared Lu. longipalpis have provided a descriptive repertoire of gene expression in the whole insect, midgut, salivary gland and male reproductive organs. Nevertheless, the study of wild specimens would contribute a unique insight into the development of novel bioinsecticides. Given the recent VL outbreak in Argentina and the compelling need to develop appropriate control strategies, this study focused on wild male and female Lu. longipalpis from an Argentine endemic (Posadas, Misiones) and a Brazilian non-endemic (Lapinha Cave, Minas Gerais) VL location. In this study, total RNA was extracted from the sand flies, submitted to sequence independent amplification and high-throughput pyrosequencing. This is the first time an unbiased and comprehensive transcriptomic approach has been used to analyse an infectious disease vector in its natural environment. Transcripts identified in the sand flies showed characteristic profiles which correlated with the environment of origin and with taxa previously identified in these same specimens. Among these, various genes represented putative targets for vector control via RNA interference (RNAi). PMID:23554910
McCarthy, Christina B; Santini, María Soledad; Pimenta, Paulo F P; Diambra, Luis A
Landscape associations of the sand fly, Lutzomyia apache, Young and Perkins in the southwestern U.S. were investigated by light/suction trap sampling and the development of a GIS-generated distribution map. In the mid-Rio Grande River Valley, N.M., female and male L. apache were captured in up-draf...
The saliva of blood sucking insects contains potent pharmacologically active components that assist them in counteracting the host hemostatic and inflammatory systems during blood feeding. In addition, sand fly salivary proteins affect host immunity and have the potential to be a vaccine against Leishmania infection. In the present study, the salivary gland transcripts of Lutzomyia ayacuchensis, a vector of cutaneous leishmaniasis in Ecuadorian and Peruvian Andes, were analyzed by sequencing randomly selected clones of the salivary gland cDNA library of this sand fly. This resulted in the identification of the most abundant transcripts coding for secreted proteins. These proteins were homologous to the salivary molecules present in other sand flies including the RGD-containing peptide, PpSP15/SL1 family protein, yellow-related protein, putative apyrase, antigen 5-related protein, D7 family protein, and 27 kDa salivary protein. Of note, homologues of maxadilan, an active vasodilator abundantly present in saliva of Lutzomyia longipalpis, were not identified. This analysis is the first description of salivary proteins from a sand fly of the subgenus Helcocyrtomyia and from vector of cutaneous leishmaniasis in the New World. The present analysis will provide further insights into the evolution of salivary components in blood sucking arthropods. PMID:23000112
Kato, Hirotomo; Jochim, Ryan C; Gomez, Eduardo A; Uezato, Hiroshi; Mimori, Tatsuyuki; Korenaga, Masataka; Sakurai, Tatsuya; Katakura, Ken; Valenzuela, Jesus G; Hashiguchi, Yoshihisa
Background Sand fly saliva contains molecules that modify the host's hemostasis and immune responses. Nevertheless, the role played by this saliva in the induction of key elements of inflammatory responses, such as lipid bodies (LB, also known as lipid droplets) and eicosanoids, has been poorly investigated. LBs are cytoplasmic organelles involved in arachidonic acid metabolism that form eicosanoids in response to inflammatory stimuli. In this study, we assessed the role of salivary gland sonicate (SGS) from Lutzomyia (L.) longipalpis, a Leishmania infantum chagasi vector, in the induction of LBs and eicosanoid production by macrophages in vitro and ex vivo. Methodology/Principal Findings Different doses of L. longipalpis SGS were injected into peritoneal cavities of C57BL/6 mice. SGS induced increased macrophage and neutrophil recruitment into the peritoneal cavity at different time points. Sand fly saliva enhanced PGE2 and LTB4 production by harvested peritoneal leukocytes after ex vivo stimulation with a calcium ionophore. At three and six hours post-injection, L. longipalpis SGS induced more intense LB staining in macrophages, but not in neutrophils, compared with mice injected with saline. Moreover, macrophages harvested by peritoneal lavage and stimulated with SGS in vitro presented a dose- and time-dependent increase in LB numbers, which was correlated with increased PGE2 production. Furthermore, COX-2 and PGE-synthase co-localized within the LBs induced by L. longipalpis saliva. PGE2 production by macrophages induced by SGS was abrogated by treatment with NS-398, a COX-2 inhibitor. Strikingly, SGS triggered ERK-1/2 and PKC-? phosphorylation, and blockage of the ERK-1/2 and PKC-? pathways inhibited the SGS effect on PGE2 production by macrophages. Conclusion In sum, our results show that L. longipalpis saliva induces lipid body formation and PGE2 production by macrophages ex vivo and in vitro via the ERK-1/2 and PKC-? signaling pathways. This study provides new insights regarding the pharmacological mechanisms whereby L. longipalpis saliva influences the early steps of the host's inflammatory response.
Araujo-Santos, Theo; Prates, Deboraci Brito; Andrade, Bruno Bezerril; Nascimento, Danielle Oliveira; Clarencio, Jorge; Entringer, Petter F.; Carneiro, Alan B.; Silva-Neto, Mario A. C.; Miranda, Jose Carlos; Brodskyn, Claudia Ida; Barral, Aldina; Bozza, Patricia T.; Borges, Valeria Matos
Background Molecules involved in pheromone biosynthesis may represent alternative targets for insect population control. This may be particularly useful in managing the reproduction of Lutzomyia longipalpis, the main vector of the protozoan parasite Leishmania infantum in Latin America. Besides the chemical identity of the major components of the L. longipalpis sex pheromone, there is no information regarding the molecular biology behind its production. To understand this process, obtaining information on which genes are expressed in the pheromone gland is essential. Methods In this study we used a transcriptomic approach to explore the pheromone gland and adjacent abdominal tergites in order to obtain substantial general sequence information. We used a laboratory-reared L. longipalpis (one spot, 9-Methyl GermacreneB) population, captured in Lapinha Cave, state of Minas Gerais, Brazil for this analysis. Results From a total of 3,547 cDNA clones, 2,502 high quality sequences from the pheromone gland and adjacent tissues were obtained and assembled into 1,387 contigs. Through blast searches of public databases, a group of transcripts encoding proteins potentially involved in the production of terpenoid precursors were identified in the 4th abdominal tergite, the segment containing the pheromone gland. Among them, protein-coding transcripts for four enzymes of the mevalonate pathway such as 3-hydroxyl-3-methyl glutaryl CoA reductase, phosphomevalonate kinase, diphosphomevalonate descarboxylase, and isopentenyl pyrophosphate isomerase were identified. Moreover, transcripts coding for farnesyl diphosphate synthase and NADP+ dependent farnesol dehydrogenase were also found in the same tergite. Additionally, genes potentially involved in pheromone transportation were identified from the three abdominal tergites analyzed. Conclusion This study constitutes the first transcriptomic analysis exploring the repertoire of genes expressed in the tissue containing the L. longipalpis pheromone gland as well as the flanking tissues. Using a comparative approach, a set of molecules potentially present in the mevalonate pathway emerge as interesting subjects for further study regarding their association to pheromone biosynthesis. The sequences presented here may be used as a reference set for future research on pheromone production or other characteristics of pheromone communication in this insect. Moreover, some matches for transcripts of unknown function may provide fertile ground of an in-depth study of pheromone-gland specific molecules.
The saliva of blood-sucking arthropods contains powerful pharmacologically active substances and may be a vaccine target against some vector-borne diseases. Subtractive cloning combined with biochemical approaches was used to discover activities in the salivary glands of the hematophagous fly Lutzomyia longipalpis. Sequences of nine full-length cDNA clones were obtained, five of which are possibly associated with blood-meal acquisition, each having cDNA similarity to: (i) the bed bug Cimex lectularius apyrase, (ii) a 5'-nucleotidase/phosphodiesterase, (iii) a hyaluronidase, (iv) a protein containing a carbohydrate-recognition domain (CRD), and (v) a RGD-containing peptide with no significant matches to known proteins in the BLAST databases. Following these findings, we observed that the salivary apyrase activity of L. longipalpis is indeed similar to that of Cimex apyrase in its metal requirements. The predicted isoelectric point of the putative apyrase matches the value found for Lutzomyia salivary apyrase. A 5'-nucleotidase, as well as hyaluronidase activity, was found in the salivary glands, and the CRD-containing cDNA matches the N-terminal sequence of the HPLC-purified salivary anticlotting protein. A cDNA similar to alpha-amylase was discovered and salivary enzymatic activity demonstrated for the first time in a blood-sucking arthropod. Full-length clones were also found coding for three proteins of unknown function matching, respectively, the N-terminal sequence of an abundant salivary protein, having similarity to the CAP superfamily of proteins and the Drosophila yellow protein. Finally, two partial sequences are reported that match possible housekeeping genes. Subtractive cloning will considerably enhance efforts to unravel the salivary pharmacopeia of blood-sucking arthropods. PMID:10611354
Charlab, R; Valenzuela, J G; Rowton, E D; Ribeiro, J M
A new species of phlebotomine sand fly, Lutzomyia adamsi n. sp., is described and illustrated from specimens collected during August 1994, in Sandia, Department of Puno-Peru. According to the Oficina Nacional de Evaluacion de Recursos Naturales(ONERN 1976), this locality is situated in the life zone known as humid, mountain, low tropical forest (bh-MBT). Many areas in the northern part of Puno, mainly in the Inambari and Tambopata basins, are endemic to leishmaniasis. These areas are the continuation of others, largely known as "leishmaniasic" in the departments of Cusco and Madre de Dios. The morphological characteristics indicated that this species belongs to the genus Lutzomyia, subgenus Helcocyrtomyia Barretto, 1962. PMID:9698842
Fernandez, R; Galati, E B; Carbajal, F; Wooster, M T; Watts, D M
Background Sand flies (Diptera, Psychodidae, Phlebotominae) in the genus Lutzomyia are the predominant vectors of the protozoan disease leishmaniasis in the New World. Within the watershed of the Panama Canal, the cutaneous form of leishmaniasis is a continuous health threat for residents, tourists and members of an international research community. Here we report the results of screening a tropical forest assemblage of sand fly species for infection by both Leishmania and a microbe that can potentially serve in vector population control, the cytoplasmically transmitted rickettsia, Wolbachia pipientis. Knowing accurately which Lutzomyia species are present, what their evolutionary relationships are, and how they are infected by strains of both Leishmania and Wolbachia is of critical value for building strategies to mitigate the impact of this disease in humans. Methodology and Findings We collected, sorted and then used DNA sequences to determine the diversity and probable phylogenetic relationships of the Phlebotominae occurring in the understory of Barro Colorado Island in the Republic of Panama. Sequence from CO1, the DNA barcoding gene, supported 18 morphology-based species determinations while revealing the presence of two possible “cryptic” species, one (Lu. sp. nr vespertilionis) within the Vespertilionis group, the other (Lu. gomezi) within the Lutzomyia-cruciata series. Using ITS-1 and “minicircle” primers we detected Leishmania DNA in 43.3% of Lu. trapidoi, 26.3% of Lu. gomezi individuals and in 0% of the other 18 sand fly species. Identical ITS-1 sequence was obtained from the Leishmania infecting Lu. trapidoi and Lu. gomezi, sequence which was 93% similar to Leishmania (viannia) naiffi in GenBank, a species previously unknown in Panama, but recognized as a type of cutaneous leishmaniasis vectored broadly across northern and central South America. Distinct strains of the intracellular bacterium Wolbachia were detected in three of 20 sand fly species, including Lu. trapidoi, in which it frequently co-occurred with Leishmania. Conclusions Both morphological and molecular methods were used to examine an assemblage of 20 sand fly species occurring in the forests of the Panama Canal area. Two of these species, members of separate clades, were found to carry Leishmania at high frequency and hence are likely vectors of leishmaniasis to humans or other mammal species. A single Leishmania species, identified with high confidence as Le. naiffi, was carried by both species. That Le. naiffi is known to cause cutaneous lesions in South America but has hitherto not been reported or implicated in Panama opens the possibility that its range has recently expanded to include the Isthmus or that it occurs as a recent introduction. The occurrence of Leishmania and Wolbachia in Lu. trapidoi identifies one important vector of the disease as a potential target for gene introductions using Wolbachia population sweeps.
Azpurua, Jorge; De La Cruz, Dianne; Valderama, Anayansi; Windsor, Donald
The sand fly Lutzomyia longipalpis is the main vector of Leishmania (L.) infantum (Nicolle), the causative agent of American visceral leishmaniasis (AVL) in the New World. Male Lu. longipalpis have secretory glands which produce sex pheromones in either abdominal tergites 4 or 3 and 4. These glands are sites of sex pheromone production and each pheromone type may represent true sibling species. In Latin America, apart from Lu. pseudolongipalpis Arrivillaga and Feliciangeli from Venezuela, populations of Lu. longipalpis s.l. can be identified by their male-produced sex pheromones: (S)-9-methylgermacrene-B, 3-methyl-?-himachalene and the two cembrenes, 1 and 2. In this study, we present the results of a coupled gas chromatography - mass spectrometry analysis of the pheromones of males Lu. longipalpis captured in an endemic area of visceral leishmaniasis in Asunción, Paraguay. Our results show that Lu. longipalpis from this site produce (S)-9-methylgermacrene-B which has also been found in Lu. longipalpis from different areas of Brazil, Colombia and Central America.
Brazil, Reginaldo P; Caballero, Norath Natalia; Hamilton, James Gordon C
The dispersal pattern of the sand fly Lutzomyia neivai was studied through mark-release-recapture experiments in an American cutaneous leishmaniasis endemic rural area in Southeastern Brazil. Over 6500 specimens were marked with fluorescent powder and released in forest edge and peridomicile habitats from August to November 1999, February and April 2000. Recapture attempts were made using Shannon and CDC traps up to eight successive nights after releases. A total of 493 (7.58%) specimens were recaptured. The number of recaptured males and females of L. neivai in CDC traps was not affected by the distance between the trap and the release points. Approximately 90% of males and females recaptured in CDC traps were caught up to 70 m from the release points. The maximum female flight range recorded was 128 m. The average flight range per day was less than 60 m for males and females. Of the flies released in forest edge, approximately 16% of the recaptured females were caught in Shannon traps in the peridomicile habitat. The results indicate that the movements of L. neivai are spatially focal and the possibility of dispersion from forest to peridomicile habitat may be an important way of contracting leishmaniasis in dwellings. PMID:16410957
Casanova, Cláudio; Costa, Antonio I P; Natal, Delsio
Belo Horizonte, the capital of the southeastern state of Minas Gerais, Brazil, and the fourth-largest city in the country, has the highest incidence of human visceral leishmaniasis (VL) together with a high prevalence of canine VL. The Northeast Sanitary District (NSD) of Belo Horizonte has the largest historical average of human VL cases in the metropolitan region, and is classified as a priority area for epidemiological and entomological monitoring of the disease. The objectives of the present study were to determine the seasonal variation in phlebotomine fauna and to describe the environmental situations in the NSD through characterization of peri-domiciles and application of geographical information system analysis. Entomological captures were performed every two weeks during the period July 2006 to June 2007 using HP light traps placed at 16 locations where cases of human VL had been reported in 2005. The environmental characterization of these locations was accomplished using forms and photographic images. Spatial analyses was used to determine the influence of vegetation, hydrography, altitude and pockets of poverty on the occurrence of cases of human and canine VL, and of phlebotomine vectors. A total of 633 phlebotomines belonging to the subtribes Psychodopygina and Lutzomyina were captured and, of these, 75% were identified as Nyssomyia whitmani and 11% as Lutzomyia longipalpis. The majority of the studied peri-domiciles presented inadequate hygienic conditions that would favor the development of phlebotomines. No significant correlations could be established between biogeographical aspects and either the incidence of human and canine VL or the occurrence of phlebotomines. The proximity of areas with vegetation, villages, slums and open watercourses exerted little influence on the incidence of VL. These findings reinforce the urbanization of the VL profile since the disease occurred in locations where conditions that have been classically related to its prevalence were not present. The results reported herein will be important for implementing measures against VL in the study area. PMID:21110938
Saraiva, Lara; Andrade Filho, José Dilermando; Falcão, Alda Lima; de Carvalho, Deborah Aparecida Alves; de Souza, Carina Margonari; Freitas, Christian Rezende; Gomes Lopes, Camila Ragonezi; Moreno, Elizabeth Castro; Melo, Maria Norma
Background Leishmania parasites are transmitted in the presence of sand fly saliva. Together with the parasite, the sand fly injects salivary components that change the environment at the feeding site. Mice immunized with Phlebotomus papatasi salivary gland (SG) homogenate are protected against Leishmania major infection, while immunity to Lutzomyia intermedia SG homogenate exacerbated experimental Leishmania braziliensis infection. In humans, antibodies to Lu. intermedia saliva are associated with risk of acquiring L. braziliensis infection. Despite these important findings, there is no information regarding the repertoire of Lu. intermedia salivary proteins. Methods and Findings A cDNA library from the Salivary Glands (SGs) of wild-caught Lu. intermedia was constructed, sequenced, and complemented by a proteomic approach based on 1D SDS PAGE and mass/mass spectrometry to validate the transcripts present in this cDNA library. We identified the most abundant transcripts and proteins reported in other sand fly species as well as novel proteins such as neurotoxin-like proteins, peptides with ML domain, and three small peptides found so far only in this sand fly species. DNA plasmids coding for ten selected transcripts were constructed and used to immunize BALB/c mice to study their immunogenicity. Plasmid Linb-11—coding for a 4.5-kDa protein—induced a cellular immune response and conferred protection against L. braziliensis infection. This protection correlated with a decreased parasite load and an increased frequency of IFN-?-producing cells. Conclusions We identified the most abundant and novel proteins present in the SGs of Lu. intermedia, a vector of cutaneous leishmaniasis in the Americas. We also show for the first time that immunity to a single salivary protein from Lu. intermedia can protect against cutaneous leishmaniasis caused by L. braziliensis.
Carneiro, Marcia W.; Miranda, Jose Carlos; Clarencio, Jorge; Barral-Netto, Manoel; Brodskyn, Claudia; Barral, Aldina; Ribeiro, Jose M. C.; Valenzuela, Jesus G.; de Oliveira, Camila I.
Background Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Latin America, is a complex of sibling species. In Brazil, a number of very closely related sibling species have been revealed by the analyses of copulation songs, sex pheromones and molecular markers. However, the level of divergence and gene flow between the sibling species remains unclear. Brazilian populations of this vector can be divided in two main groups: one producing Burst-type songs and the Cembrene-1 pheromone and a second more diverse group producing various Pulse song subtypes and different pheromones. Methodology/Principal Findings We analyzed 21 nuclear loci in two pairs of Brazilian populations: two sympatric populations from the Sobral locality (1S and 2S) in northeastern Brazil and two allopatric populations from the Lapinha and Pancas localities in southeastern Brazil. Pancas and Sobral 2S are populations of the Burst/Cembrene-1 species while Lapinha and Sobral 1S are two putative incipient species producing the same pheromone and similar Pulse song subtypes. The multilocus analysis strongly suggests the occurrence of gene flow during the divergence between the sibling species, with different levels of introgression between loci. Moreover, this differential introgression is asymmetrical, with estimated gene flow being higher in the direction of the Burst/Cembrene-1 species. Conclusions/Significance The results indicate that introgressive hybridization has been a crucial phenomenon in shaping the genome of the L. longipalpis complex. This has possible epidemiological implications and is particularly interesting considering the potential for increased introgression caused by man-made environmental changes and the current trend of leishmaniasis urbanization in Brazil.
Mazzoni, Camila J.; Souza, Nataly A.; Machado, Ricardo C.; Bruno, Rafaela V.
Background The scarcity of information on the immature stages of sand flies and their preferred breeding sites has resulted in the focus of vectorial control on the adult stage using residual insecticide house-spraying. This strategy, along with the treatment of human cases and the euthanasia of infected dogs, has proven inefficient and visceral leishmaniasis continues to expand in Brazil. Identifying the breeding sites of sand flies is essential to the understanding of the vector's population dynamic and could be used to develop novel control strategies. Methodology/Principal finding In the present study, an intensive search for the breeding sites of Lutzomyia longipalpis was conducted in urban and peri-urban areas of two municipalities, Promissão and Dracena, which are endemic for visceral leishmaniasis in São Paulo State, Brazil. During an exploratory period, a total of 962 soil emergence traps were used to investigate possible peridomiciliary breeding site microhabitats such as: leaf litter under tree, chicken sheds, other animal sheds and uncovered debris. A total of 160 sand flies were collected and 148 (92.5%) were L. longipalpis. In Promissão the proportion of chicken sheds positive was significantly higher than in leaf litter under trees. Chicken shed microhabitats presented the highest density of L. longipalpis in both municipalities: 17.29 and 5.71 individuals per square meter sampled in Promissão and Dracena respectively. A contagious spatial distribution pattern of L. longipalpis was identified in the emergence traps located in the chicken sheds. Conclusion The results indicate that chicken sheds are the preferential breeding site for L. longipalpis in the present study areas. Thus, control measures targeting the immature stages in chicken sheds could have a great effect on reducing the number of adult flies and consequently the transmission rate of Leishmania (Leishmania) infantum chagasi.
Casanova, Claudio; Andrighetti, Maria T. M.; Sampaio, Susy M. P.; Marcoris, Maria L. G.; Colla-Jacques, Fernanda E.; Prado, Angelo P.
The lengths of the male genital filaments and female spermathecal ducts were measured in phlebotomine sand flies of the Lutzomyia intermedia species complex and the ratios between these characters calculated. Ratios for L. intermedia s. s. from Northeast vs Southeast Brazil (Espírito Santo and Minas Gerais), Espírito Santo/Minas Gerais vs Rio de Janeiro/São Paulo and L. intermedia vs L. neivai were significantly different at P < 0.1, 0.05 and 0.01 respectively when compared using ANOVA. The spermathecal ducts and genital filaments of L. intermedia were significantly longer than those of L. neivai (P < 0.01) and could be used to differentiate these species. The taxonomic and biological significance of these differences is discussed. PMID:12973526
Marcondes, Carlos Brisola; Alexander, Bruce
The phlebotomine sand fly Lutzomyia longipalpis takes blood from a variety of wild and domestic animals and transmits Leishmania (Leishmania) infantum chagasi, etiological agent of American visceral leishmaniasis. Blood meal identification in sand flies has depended largely on serological methods but a new protocol described here uses filter-based technology to stabilise and store blood meal DNA, allowing subsequent PCR identification of blood meal sources, as well as parasite detection, in blood-fed sand flies. This technique revealed that 53.6% of field-collected sand flies captured in the back yards of houses in Teresina (Brazil) had fed on chickens. The potential applications of this technique in epidemiological studies and strategic planning for leishmaniasis control programmes are discussed.
Sant'Anna, Mauricio R.V.; Jones, Nathaniel G.; Hindley, Jonathan A.; Mendes-Sousa, Antonio F.; Dillon, Rod J.; Cavalcante, Reginaldo R.; Alexander, Bruce; Bates, Paul A.
The low dispersal capacity of sand flies could lead to population isolation due to geographic barriers, climate variation, or to population fragmentation associated with specific local habitats due to landscape modification. The phlebotomine sand fly Lutzomyia cruciata has a wide distribution throughout Mexico and is a vector of Leishmania mexicana in the southeast. The aim of this study was to evaluate the genetic diversity, structure, and divergence within and among populations of Lu. cruciata in the state of Chiapas, and to infer the intra-specific phylogeny using the 3' end of the mitochondrial cytochrome b gene. We analyzed 62 sequences from four Lu. cruciata populations and found 26 haplotypes, high genetic differentiation and restricted gene flow among populations (Fst=0.416, Nm=0.701, p<0.001). The highest diversity values were recorded in populations from Loma Bonita and Guadalupe Miramar. Three lineages (100% bootstrap and 7% overall divergence) were identified using a maximum likelihood phylogenetic analysis which showed high genetic divergence (17.2-22.7%). A minimum spanning haplotype network also supported separation into three lineages. Genetic structure and divergence within and among Lu. cruciata populations are hence affected by geographic heterogeneity and evolutionary background. Data obtained in the present study suggest that Lu. cruciata in the state of Chiapas consists of at least three lineages. Such findings may have implications for vector capacity and hence for vector control strategies. PMID:23416432
Pech-May, Angélica; Marina, Carlos F; Vázquez-Domínguez, Ella; Berzunza-Cruz, Miriam; Rebollar-Téllez, Eduardo A; Narváez-Zapata, José A; Moo-Llanes, David; Ibáñez-Bernal, Sergio; Ramsey, Janine M; Becker, Ingeborg
Leishmania species of the Viannia subgenus are responsible for most cases of New World tegumentary leishmaniasis. However, little is known about the vectors involved in disease transmission in the Amazon regions of Peru. We used a novel real-time polymerase chain reaction (PCR) to assess Leishmania infections in phlebotomines collected in rural areas of Madre de Dios, Peru. A total of 1,299 non-blood fed female sand flies from 33 species were captured by using miniature CDC light traps. Lutzomyia auraensis was the most abundant species (63%) in this area. Seven of 164 pools were positive by PCR for Leishmania by kinetoplast DNA. The real-time PCR identified four Lu. auraensis pools as positive for L. (Viannia) lainsoni and L. (V.) braziliensis. The minimum infection prevalence for Lu. auraensis was estimated to be 0.6% (95% confidence interval = 0.20–1.42%). Further studies are needed to assess the importance of Lu. auraensis in the transmission of New World tegumentary leishmaniasis in hyperendemic areas of Peru.
Valdivia, Hugo O.; De Los Santos, Maxy B.; Fernandez, Roberto; Baldeviano, G. Christian; Zorrilla, Victor O.; Vera, Hubert; Lucas, Carmen M.; Edgel, Kimberly A.; Lescano, Andres G.; Mundal, Kirk D.; Graf, Paul C. F.
Using massive cDNA sequencing, proteomics and customized computational biology approaches, we have isolated and identified the most abundant secreted proteins from the salivary glands of the sand fly Lutzomyia longipalpis. Out of 550 randomly isolated clones from a full-length salivary gland cDNA library, we found 143 clusters or families of related proteins. Out of these 143 families, 35 were predicted to be secreted proteins. We confirmed, by Edman degradation of Lu. longipalpis salivary proteins, the presence of 17 proteins from this group. Full-length sequence for 35 cDNA messages for secretory proteins is reported, including an RGD-containing peptide, three members of the yellow-related family of proteins, maxadilan, a PpSP15-related protein, six members of a family of putative anticoagulants, an antigen 5-related protein, a D7-related protein, a cDNA belonging to the Cimex apyrase family of proteins, a protein homologous to a silk protein with amino acid repeats resembling extracellular matrix proteins, a 5'-nucleotidase, a peptidase, a palmitoyl-hydrolase, an endonuclease, nine novel peptides and four different groups of proteins with no homologies to any protein deposited in accessible databases. Sixteen of these proteins appear to be unique to sand flies. With this approach, we have tripled the number of isolated secretory proteins from this sand fly. Because of the relationship between the vertebrate host immune response to salivary proteins and protection to parasite infection, these proteins are promising markers for vector exposure and attractive targets for vaccine development to control Leishmania chagasi infection. PMID:15371479
Valenzuela, Jesus G; Garfield, Mark; Rowton, Edgar D; Pham, Van M
Background Visceral Leishmaniasis is a serious human disease transmitted, in the New World, by Lutzomyia longipalpis sand flies. Natural resistance to Leishmania transmission in residents of endemic areas has been attributed to the acquisition of immunity to sand fly salivary proteins. One theoretical way to accelerate the acquisition of this immunity is to increase the density of antigen-presenting cells at the sand fly bite site. Here we describe a novel tissue platform that can be used for this purpose. Methodology/Principal Findings BluePort is a well-vascularized and macrophage-rich compartment induced in the subcutaneous tissue of mice via injection of agarose beads covered with Cibacron blue. We describe the sequence of inflammatory events leading to its formation and how it can be used to study the dermal response to the bite of L. longipalpis sand flies. Results presented indicate that a shift in the inflammatory response, from neutrophilic to eosinophilic, is the main histopathological feature associated with the immunity acquired through repeated exposure to the bite of sand flies, and that the BluePort tissue compartment could be used to accelerate this process. In addition, changes observed inside the BluePort parenchyma indicate that it could be used to study complex immunobiological processes, and to develop ectopic secondary lymphoid structures. Conclusions/Significance Understanding the characteristics of the dermal response to the bite of sand flies is a critical element of strategies to control leishmaniasis using vaccines that target salivary proteins. Finding that dermal eosinophilia is such a prominent component of the anti-salivary immunity induced by repeated exposure to sand fly bites raises one important consideration: how to avoid the immunological conflict derived from a protective Th2-driven immunity directed to sand fly saliva with a protective Th1-driven immunity directed to the parasite. The BluePort platform is an ideal tool to address experimentally this conundrum.
Mejia, J. Santiago; Toot-Zimmer, Amanda L.; Schultheiss, Patricia C.; Beaty, Barry J.; Titus, Richard G.
Objective Blood-sucking arthropods salivary glands (SGs) contain a remarkable diversity of antihemostatics. The aim of this study was to identify the unique salivary anticoagulant of the sand fly Lutzomyia longipalpis, which remained elusive for decades. Methods and Results Several L. longipalpis salivary proteins were expressed in HEK293 cells and screened for inhibition of blood coagulation. A novel 32.4-kDa molecule, named Lufaxin, was identified as a slow, tight, non-competitive, and reversible inhibitor of Factor Xa (FXa). Notably, Lufaxin primary sequence does not share similarity to any physiological or salivary inhibitors of coagulation reported to date. Lufaxin is specific for FXa and does not interact with FX, DEGR- FXa, or 15 other enzymes. In addition, Lufaxin blocks prothrombinase and increases both PT and aPTT. Surface plasmon resonance experiments revealed that FXa binds Lufaxin with a KD ~3 nM, and isothermal titration calorimetry determined a stoichiometry of 1:1. Lufaxin also prevents PAR2 activation by FXa in the MDA-MB-231 cell line and abrogates edema formation triggered by injection of FXa in the paw of mice. Moreover, Lufaxin prevents FeCl3-induced carotid artery thrombus formation and prolongs aPTT ex vivo, implying that it works as an anticoagulant in vivo. Finally, SG of sandflies was found to inhibit FXa and to interact with the enzyme. Conclusion Lufaxin belongs to a novel family of slow-tight FXa inhibitors, which display antithrombotic and antiinflamatory activities. It is a useful tool to understand FXa structural features and its role in pro-hemostatic and pro-inflammatory events.
Collin, Nicolas; Assumpcao, Teresa C. F.; Mizurini, Daniella M.; Gilmore, Dana; Dutra-Oliveira, Angelica; Kotsyfakis, Michalis; Sa-Nunes, Anderson; Teixeira, Clarissa; Ribeiro, Jose M. C.; Monteiro, Robson Q.; Valenzuela, Jesus G.; Francischetti, Ivo M. B.
Several studies have pointed out the immunomodulatory properties of the Salivary Gland Extract (SGE) from Lutzomyia longipalpis. We aimed to identify the SGE component (s) responsible for its effect on ovalbumin (OVA)-induced neutrophil migration (NM) and to evaluate the effect of SGE and components in the antigen-induced arthritis (AIA) model. We tested the anti-arthritic activities of SGE and the recombinant LJM111 salivary protein (rLJM111) by measuring the mechanical hypernociception and the NM into synovial cavity. Furthermore, we measured IL-17, TNF-? and IFN-? released by lymph nodes cells stimulated with mBSA or anti-CD3 using enzyme-linked immunosorbent assay (ELISA). Additionally, we tested the effect of SGE and rLJM111 on co-stimulatory molecules expression (MHC-II and CD-86) by flow cytometry, TNF-? and IL-10 production (ELISA) of bone marrow-derived dendritic cells (BMDCs) stimulated with LPS, chemotaxis and actin polymerization from neutrophils. Besides, the effect of SGE on CXCR2 and GRK-2 expression on neutrophils was investigated. We identified one plasmid expressing the protein LJM111 that prevented NM in OVA-challenged immunized mice. Furthermore, both SGE and rLJM111 inhibited NM and pain sensitivity in AIA and reduced IL-17, TNF-? and IFN-?. SGE and rLJM111 also reduced MHC-II and CD-86 expression and TNF-? whereas increased IL-10 release by LPS-stimulated BMDCs. SGE, but not LJM 111, inhibited neutrophils chemotaxis and actin polymerization. Additionally, SGE reduced neutrophil CXCR2 expression and increased GRK-2. Thus, rLJM111 is partially responsible for SGE mechanisms by diminishing DC function and maturation but not chemoattraction of neutrophils.
Grespan, Renata; Lemos, Henrique P.; Carregaro, Vanessa; Verri, Waldiceu A.; Souto, Fabricio O.; de Oliveira, Carlo J.F.; Teixeira, Clarissa; Ribeiro, Jose Marcos; Valenzuela, Jesus G.; Cunha, Fernando Q.
This study investigated the sandfly fauna of two quartzite caves in the Espinhaço Mountain Range, located in the municipality of Diamantina, state Minas Gerais. From August 2010-July 2011, entomological sampling was performed in the caves of Salitre and Monte Cristo with two HP light traps exposed in the photic and aphotic zones of each cave. The sandfly fauna consisted of 17 species, among which Lutzomyia cipoensis was predominant (54.76%). The male/female ratio in the total captures was 1:2.5. The aphotic zone showed the highest frequency of specimens captured (65%). A greater density of sandflies occurred during the summer (January-February), coinciding with the period of higher temperatures, humidity and rainfall. The presence of Lutzomyia longipalpis, Lutzomyia whitmani and Lutzomyia pessoai, proven or suspected vectors of leishmaniasis, is of concern because the area is visited by many tourists. PMID:23295752
Barata, Ricardo Andrade; Apolinário, Estefânia Conceição
Visceral leishmaniasis is a systemic infectious disease that can cause to a severe, potentially life-threatening chronic condition in humans. Risk factors for infection in urban areas have been associated with poor living conditions, the presence of sand fly vectors and infected pets. This study aimed to describe sand fly and canine infection in the neighborhoods of human visceral leishmaniasis occurrence in the city of Cuiabá, Mato Grosso State, central-western Brazil, reported between January 2005 and December 2006. A total of 1,909 sand flies were collected. They were predominantly males and the most frequent species were Lutzomyia cruzi (81.25%), Lutzomyia whitmani (13.88%) and Lutzomyia longipalpis (2.62%). The sand fly density was not significantly correlated with the variation of environmental factors. The prevalence of canine visceral leishmaniasis in the neighborhoods studied was 26.82% and it was found that areas with high density of vectors coincided with areas of high prevalence of dogs and those with the highest rates of human cases. The study of vectors and other potential hosts are essential for a good understanding of visceral leishmaniasis and the related public health concerns, aiming at the prevention and control of leishmaniasis in the city of Cuiabá, Mato Grosso State. PMID:21961754
Mestre, Gustavo Leandro da Cruz; Ribeiro, Ana Lúcia Maria; Miyazaki, Rosina Djunko; Rodrigues, Jorge Senatore Vargas; de Almeida, Arleana do Bom Parto Ferreira; Sousa, Valéria Régia Franco; Missawa, Nanci Akemi
The distribution and relative abundance of sand fly species were studied in the municipality of Barreirinhas, Maranhão State, Brazil, around the Lençóis Maranhenses National Park, from January to June 2005, August 2004, July 2005, and September/2008. A total of 6,658 specimens were captured. The most frequent species were Lutzomyia whitmani (46.6%), L. longipalpis (29.9%), L. evandroi (17.1%), and L. lenti (4.8%), while L. termitophila, L. flaviscutellata, L. migonei, L. infraspinosa, L. sordellii, L. wellcomei, L. antunesi, and L. trinidadensis represented 1.6%. The presence of Leishmania vector species explains the high detection rate for tegumentary leishmaniasis in 2000 (308.2), 2001 (310.9), 2002 (338.2), and 2005 (313.6) and active foci of human visceral leishmaniasis in the municipality of Barreirinhas. PMID:20209223
Rebêlo, José Manuel Macário; Assunção Júnior, Antonildes Nascimento; Silva, Orleans; Moraes, Jorge Luiz Pinto
Background American cutaneous leishmaniasis (ACL) is a re-emerging disease in the state of São Paulo, Brazil. It is important to understand both the vector and disease distribution to help design control strategies. As an initial step in applying geographic information systems (GIS) and remote sensing (RS) tools to map disease-risk, the objectives of the present work were to: (i) produce a single database of species distributions of the sand fly vectors in the state of São Paulo, (ii) create combined distributional maps of both the incidence of ACL and its sand fly vectors, and (iii) thereby provide individual municipalities with a source of reference material for work carried out in their area. Results A database containing 910 individual records of sand fly occurrence in the state of São Paulo, from 37 different sources, was compiled. These records date from between 1943 to 2009, and describe the presence of at least one of the six incriminated or suspected sand fly vector species in 183/645 (28.4%) municipalities. For the remaining 462 (71.6%) municipalities, we were unable to locate records of any of the six incriminated or suspected sand fly vector species (Nyssomyia intermedia, N. neivai, N. whitmani, Pintomyia fischeri, P. pessoai and Migonemyia migonei). The distribution of each of the six incriminated or suspected vector species of ACL in the state of São Paulo were individually mapped and overlaid on the incidence of ACL for the period 1993 to 1995 and 1998 to 2007. Overall, the maps reveal that the six sand fly vector species analyzed have unique and heterogeneous, although often overlapping, distributions. Several sand fly species - Nyssomyia intermedia and N. neivai - are highly localized, while the other sand fly species - N. whitmani, M. migonei, P. fischeri and P. pessoai - are much more broadly distributed. ACL has been reported in 160/183 (87.4%) of the municipalities with records for at least one of the six incriminated or suspected sand fly vector species, while there are no records of any of these sand fly species in 318/478 (66.5%) municipalities with ACL. Conclusions The maps produced in this work provide basic data on the distribution of the six incriminated or suspected sand fly vectors of ACL in the state of São Paulo, and highlight the complex and geographically heterogeneous pattern of ACL transmission in the region. Further studies are required to clarify the role of each of the six suspected sand fly vector species in different regions of the state of São Paulo, especially in the majority of municipalities where ACL is present but sand fly vectors have not yet been identified.
The authors describe two new sandflies from Saül and Maripasoula (French Guyana). They give for each of them mensurations, drawings and differential diagnostic with related species or subspecies. PMID:498389
Abonnenc, E; Léger, N; Fauran, P
Visceral leishmaniasis (VL) has been naturally transmitted in periurban areas due to the emergence and reemergence of its vectors in such areas. Aimed to further knowledge on ecological aspects affecting the occurrence of phlebotomine sand flies in VL transmission areas in the municipality of Várzea Grande, state of Mato Grosso (MT), Brazil, sand fly captures were carried out. Monthly collections of sand flies were undertaken with CDC light-traps, which were left in both intradomiciliary and peridomiciliary areas of ten residences during four consecutive days between January 2004 and June 2006. Twenty-two species of genus Lutzomyia and one of Brumptomyia were captured. The most abundant species was Lutzomyia longipalpis (65.23%), followed by L. evandroi (16.26%), L. lenti (7.69%), L. whitmani (4.92%), L. sallesi (2.34%) and L. termitophila (1.32%). The highest density of the main VL vector, L. longipalpis, was found in peridomiciliary areas, mostly males. No significant correlation was found between environment (temperature, air relative humidity and rain fall) and phlebotomine density; although a slight increase in sand fly density has been observed in the period following rainfalls, particularly L. longipalpis. No correlation was observed between distribution and density of L. longipalpis, prevalence of human VL cases and the presence of serologically positive dogs. The presence of infected dogs, increased vector density, susceptibility rate and interruption of epidemiological surveillance may raise the risk of VL transmission to man in Várzea Grande. PMID:18209928
Missawa, Nanci Akemi; Dias, Edelberto Santos
Preliminary data of a project about the ecology of the Phlebotominae (sandflies) in a tegumentary leishmaniasis area of coconut plantation in the south of the State of Bahia, Brazil are presented. There are 60 dwellings far of one another, where existed 31 dogs and 229 inhabitants. Among them 41.5% were Montenegro positive; 37.5% from these had scars of healed ulcers and 8.8% had active ulcers. 53% of the house had dogs from which 22% were seropositive; from the 7 dogs with ulcers only 3 were seropositive. 14% of the inspected house harboured sandflies inside them. During two years of observations 72 sentinels hamsters were maintened at houses of patients with leishmaniasis ulcers, but they did not get the infection. During two years of observation, monthly collectings of sandflies were made inside house, chicken pen, curral, tree trunks and open field around a house with a patient with leishmaniasis. The following results were already obtained about the vectors: 5,614 specimens were identified as belonging to fourteen different species of sandflies. Among them Lutzomyia whitmani (92%) and Lutzomyia intermedia (4.8%) were the most abundant species. They are very anthropophilic and can be found inside houses and at peridomestic sites. Probably they are the principal vectors of the disease at domestic places. The other twelve species were less frequent and more found at sylvatic places in inspite they also bite the man. Generally the biting activity of most of the species of the area begins at 5 p.m. in the dusk and reaches its peak at 0 hour a.m., when begins declining until disapear at 7 a.m. L. whitmani was similarly collected with the same density in all lunar phases while L. intermedia was more abundant during the new moon phase. Most of the hundreds sandflies collected during the second year of observations, remains preserved in liquid nitrogen, watching for the adjustment of PCR molecular techniques to be processed for determination of the vector natural infection rates with leishmanias. Final results on all the project will be published as soon as the examination of such material has been processed. PMID:8713612
Sherlock, I A; Maia, H; Dias-Lima, A G
American cutaneous leishmaniasis (ACL) has been increasing in Pernambuco, thus becoming an important problem for Public Health. The incindence is predominant in the region called 'Zona da Mata', in the east of this state. This region corresponds geographically to the primitive area of the Atlantic forest. In order to characterize the eco-epidemiology expression of ACL in this region, two localities situated in the municipalities of Amaraji e Cortes have been selected by the criterion of higher incindence of human cases. Five stocks of patients were characterized and identified on the basis of enzyme profiles as a new variant of Leishmania (V.) braziliensis. A survey of wild and domestic animals was carried out by means of a parasitological and serological diagnosis. Through the analysis of the spleen and liver imprints, were detected amastigotes compatible with Leishmania in five Nectomys s. squamipes, five Bolomys 1. pixuna, two Rattus r. alexandrinus and one Rattus r. frugivorus. For two years we carried out monthly sandflies captures using CDC light traps as well as manual captures. Lutzomyia whitmani was predominant, which accounted for 97.4% of the total. These data indicate a strong evidence on the vector and the potential reservoirs of L. braziliensis in this region. PMID:7476230
Brandão-Filho, S P; de Carvalho, F G; de Brito, M E; Almeida, F de A; Nascimento, L A
Health service records for north-east Brazil suggest a consistent rise in numbers of cases of cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis over the past decade. In a study site in Pernambuco, prospective, cross-sectional and retrospective epidemiological surveys of infection (a positive Montenegro skin test response) and/or clinical symptoms confirmed a high current force of infection (0.092/year), and an approximately 10-fold increase in transmission during the last 10 years. Cross-sectional analysis indicated that the incidence rate among children (aged < or = 15 years) was lower than that among adult immigrants exposed for similar time periods, but there was no apparent difference in transmission rate according to gender. Coupled with the known behaviour of the local sandfly vector, Lutzomyia whitmani, this suggests that most people are infected outside their houses, rather than either indoors or while visiting remnant rainforest. The estimated proportion of infections which lead to cutaneous lesions (0.81-0.87) is relatively high for L. braziliensis areas. However, an unusually low proportion of clinical infections (0.0042) apparently leads to metastasis. PMID:10696402
Brandão-Filho, S P; Campbell-Lendrum, D; Brito, M E; Shaw, J J; Davies, C R
The aim of this study was to obtain experimental evidence that phlebotomine saliva is actually ingested during the carbohydrate ingestion phase (before and after blood digestion). The ingestion of carbohydrate was simulated as it occurs in the field by offering the insects balls of cotton soaked in sucrose, sucrose crystals or orange juice cells. The results obtained here showed that ingestion occurred under each condition investigated, as indicated by the presence of apyrase, an enzyme used as a marker to detect saliva in the insect gut and/or carbohydrate sources. Saliva ingestion by phlebotomine during the carbohydrate ingestion phase is important to explain how it could promote starch digestion and to trigger Leishmania promastigotes to follow a differentiation pathway as proposed previously by some authors. PMID:16699714
Cavalcante, Reginaldo R; Pereira, Marcos H; Freitas, Jorge M; Gontijo, Nelder de F
Background Lutzomyialongipalpis (Diptera: Psychodidae) is the major vector of Leishmania (Leishmania) infantum and thus plays a crucial role in the epidemiology of American visceral leishmaniasis (AVL). This vector is the best studied species of sand fly in the Neotropical region. Many studies claim that this vector is in fact a species complex; however there is still no consensus regarding the number of species that belong into this complex or the geographical distribution of sibling species. The aim of the present study was to analyze the genetic relationships within Lu. longipalpis populations in the state of Mato Grosso do Sul (MS), Brazil. Methodology/Principal Findings We collected 30 Lu. longipalpis (15 females and 15 males) from five localities (Campo Grande, Três Lagoas, Aquidauana, Miranda and Bonito) and 30 Lu. Cruzi from Corumbá, totaling 180 sandflies from MS, and 30 Lu. longipalpis from Estrela de Alagoas, state of Alagoas (AL), Northeast Brazil. We show that eight previously described microsatellite loci were sufficient in distinguishing Lu. longipalpis from Lu. Cruzi, which is a closely related species, and in differentiating between Lu. longipalpis collected in MS versus Estrela de Alagoas. Analyses of the genotypes revealed introgression between sympatric Lu. longipalpis and Lu. Cruzi. Conclusions/Significance Our findings support the hypothesis of cryptic species within the Lu. longipalpis complex. Furthermore, our data revealed introgression between Lu. longipalpis and Lu. cruzi. This phenomenon should be further investigated to determine the level and incidence of hybridization between these two species. We also demonstrated that microsatellite markers are a powerful tool for differentiating sand fly populations and species. The present study has elucidated the population structure of Lu. longipalpis in MS and, by extension, the Neotropical Lu. longipalpis complex itself.
Santos, Mirella F. C.; Ribolla, Paulo E. M.; Alonso, Diego P.; Andrade-Filho, Jose D.; Casaril, Aline E.; Ferreira, Alda M. T.; Fernandes, Carlos E. S.; Brazil, Reginaldo P.; Oliveira, Alessandra G.
BackgroundMidgut enzymatic activity is one of the obstacles that Leishmania must surpass to succeed in establishing infection. Trypsins are abundant digestive enzymes in most insects. We have previously described two trypsin cDNAs of L. longipalpis: one (Lltryp1) with a bloodmeal induced transcription pattern, the other (Lltryp2) with a constitutive transcription pattern. We have now characterized the expression and activity of
Erich Loza Telleria; Adriana Pereira Oliveira De Araújo; Nágila Francinete Secundino; Claudia Masini D'Avila-Levy; Yara Maria Traub-Csekö; Ben L. Kelly
BackgroundLeishmania is transmitted by female sand flies and deposited together with saliva, which contains a vast repertoire of pharmacologically active molecules that contribute to the establishment of the infection. The exposure to vector saliva induces an immune response against its components that can be used as a marker of exposure to the vector. Performing large-scale serological studies to detect vector
Ana Paula Souza; Bruno Bezerril Andrade; Dorlene Aquino; Petter Entringer; José Carlos Miranda; Ruan Alcantara; Daniel Ruiz; Manuel Soto; Clarissa R. Teixeira; Jesus G. Valenzuela; Camila Indiani de Oliveira; Cláudia Ida Brodskyn; Manoel Barral-Netto; Aldina Barral
Leishmania braziliensis is endemic in Guatemala and Belize in Central America. To help identify the vector(s) of this parasite in Guatemala, phlebotomine sand flies that were aspirated from the clothing of collectors at Tikal National Park in the Departme...
E. D. Rowton M. De Mata N. Rizzo C. H. Porter T. R. Navin
This review addresses changes in the ecology of vectors and epidemiology of vector-borne diseases which result from deforestation. Selected examples are considered from viral and parasitic infections (arboviruses, malaria, the leishmaniases, filariases, Chagas Disease and schistosomiasis) where disease patterns have been directly or indirectly influenced by loss of natural tropical forests. A wide range of activities have resulted in deforestation. These include colonisation and settlement, transmigrant programmes, logging, agricultural activities to provide for cash crops, mining, hydropower development and fuelwood collection. Each activity influences the prevalence, incidence and distribution of vector-borne disease. Three main regions are considered--South America, West & Central Africa and South-East Asia. In each, documented changes in vector ecology and behaviour and disease pattern have occurred. Such changes result from human activity at the forest interface and within the forest. They include both deforestation and reafforestation programmes. Deforestation, or activities associated with it, have produced new habitats for Anopheles darlingi mosquitoes and have caused malaria epidemics in South America. The different species complexes in South-East Asia (A. dirus, A. minimus, A. balabacensis) have been affected in different ways by forest clearance with different impacts on malaria incidence. The ability of zoophilic vectors to adapt to human blood as an alternative source of food and to become associated with human dwellings (peridomestic behaviour) have influenced the distribution of the leishmaniases in South America. Certain species of sandflies (Lutzomyia intermedia, Lu. longipalpis, Lu. whitmani), which were originally zoophilic and sylvatic, have adapted to feeding on humans in peridomestic and even periurban situations. The changes in behaviour of reservoir hosts and the ability of pathogens to adapt to new reservoir hosts in the newly-created habitats also influence the patterns of disease. In anthroponotic infections, such as Plasmodium, Onchocerca and Wuchereria, changes in disease patterns and vector ecology may be more difficult to detect. Detailed knowledge of vector species and species complexes is needed in relation to changing climate associated with deforestation. The distributions of the Anopheles gambiae and Simulium damnosum species complexes in West Africa are examples. There have been detailed longitudinal studies of Anopheles gambiae populations in different ecological zones of West Africa. Studies on Simulium damnosum cytoforms (using chromosome identification methods) in the Onchocerciasis Control Programme were necessary to detect changes in distribution of species in relation to changed habitats. These examples underline the need for studies on the taxonomy of medically-important insects in parallel with long-term observations on changing habitats.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8488073
Walsh, J F; Molyneux, D H; Birley, M H
A new species of Brazilian phlebotomine sandfly found in Brazil, municipality of Diamantina, state of Minas Gerais, is described based on males and females collected in a quartzite cave. The body of spermathecae is continuous to the individual duct, lanky and tapering at the end, with conical shaped, not striated and presenting the head with dense setae. The male presents gonostyle with four spines and a small subterminal seta and gonocoxite with one group of persistent setae. The paramere is simple with a group of small setae on the dorsal apex. The morphological features of this new species permit its inclusion in the migonei group. PMID:23295750
Barata, Ricardo Andrade; Serra e Meira, Paula Cavalcante Lamy; Carvalho, Gustavo Mayr de Lima
BACKGROUND: In the life cycle of Leishmania within the alimentary canal of sand flies the parasites have to survive the hostile environment of blood meal digestion, escape the blood bolus and attach to the midgut epithelium before differentiating into the infective metacyclic stages. The molecular interactions between the Leishmania parasites and the gut of the sand fly are poorly understood.
Ryan C Jochim; Clarissa R Teixeira; Andre Laughinghouse; Jianbing Mu; Fabiano Oliveira; Regis B Gomes; Dia-Eldin Elnaiem; Jesus G Valenzuela
Introduction. Although cases of leishmaniasis have been reported in the province of Guaviare, Colombia, no entomological studies were included to identify the Lutzomyia sand fly vector species in that area. Objective. Lutzomyia species were identified from four townships of Guaviare. Probable vectors were named based on those species involved in transmission in other areas. Materials and methods. Sampling was undertaken
Olga Lucía Cabrera; Laureano Mosquera; Erika Santamaría; Cristina Ferro
Infections of the lizard malaria parasite Plasmodium mexicanum are often genetically complex within their fence lizard host (Sceloporus occidentalis) harbouring two or more clones of parasite. The role of clonal diversity in transmission success was studied for P. mexicanum by feeding its sandfly vectors (Lutzomyia vexator and Lutzomyia stewarti) on experimentally infected lizards. Experimental infections consisted of one, two, three
A. M. Vardo-Zalik
Sporozoites of a lizard malaria parasite, Plasmodium mexicanum, developed in two species of sandfly-Lutzomyia vexatrix and Lutzomyia stewarti. Salivary glands were infected 11 days after the flies took an infective blood meal. This is the first report of a malaria parasite undergoing sporogonic development in an insect other than a mosquito and the first description of lizard malaria sporogenesis.
Stephen C. Ayala; Dwayne Lee
In Panama, species of the genus Lutzomyia are vectors of American cutaneous leishmaniasis (ACL). There is no recent ecological information that may be used to develop tools for the control of this disease. Thus, the goal of this study was to determine the composition, distribution and diversity of Lutzomyia species that serve as vectors of ACL. Sandfly sampling was conducted in forests, fragmented forests and rural environments, in locations with records of ACL. Lutzomyia gomezi, Lutzomyia panamensis and Lutzomyia trapidoi were the most widely distributed and prevalent species. Analysis of each sampling point showed that the species abundance and diversity were greatest at points located in the fragmented forest landscape. However, when the samples were grouped according to the landscape characteristics of the locations, there was a greater diversity of species in the rural environment locations. The Kruskal Wallis analysis of species abundance found that Lu. gomezi and Lu. trapidoi were associated with fragmented environments, while Lu. panamensis, Lutzomyia olmeca bicolor and Lutzomyia ylephiletor were associated with forested environments. Therefore, we suggest that human activity influences the distribution, composition and diversity of the vector species responsible for leishmaniasis in Panama. PMID:22241128
Valderrama, Anayansi; Tavares, Mara Garcia; Andrade Filho, José Dilermando
Breeding populations of phlebotomine sandflies (diptera, Psychodidae) on the floor of a rain forest in Panama were studied with soil emergence traps. The species Lutzomyia trapidoi (fairchild and Hertig) was predominant. L. panamensis (shannon), L. gomezi...
L. C. Rutledge D. A. Ellenwood
Leishmaniasis is an arthropod-transmitted zoonotic disease that is caused by protozoa of the genus Leishmania. Leishmania parasites are transmitted through bites of infective female sand flies (Lutzomyia species in the Americas and Phlebotomus species els...
Sporolzoites of a lizard malaria parasite, Plasmodium mexicanum. developed in two spcies of sandfly-Lutzomyia vexatrix and Lutzomyia stewarti. Salivary g1ands were infected 11 days after the flies took an infective blood meal. This is the first report of a malaria parasite undergoing sporogonic development In an insect other than a mosquito and the first description of lizard malaria sporogenesis. PMID:5410856
Ayala, S C; Lee, D
The WHO method for determining insecticide resistance was standardized for several species of Lutzomyia sand flies under laboratory and field conditions. The biological assays were applied solely to optimize the conditions for the control, i.e., without insecticide, and to estimate mortality due to handling or other unfavorable conditions. Adult female flies from 3 laboratory colonies and one field strain were tested: two laboratory strains of Lutzomyia longipalpis, one laboratory strain of Lutzomyia serrana and one field-collected strain of Lutzomyia quasitownsendi. The WHO method was compared with one modified in which, during the post-exposure period, the recommended plain tube apparatus was replaced with a plastic container layered with damp plaster of Paris. Three paper substrate types were compared under each condition: olive oil additive, silicon oil additive and plain paper. The measured variable was percent mortality in 24 h. For the WHO protocol, the L. longipalpis strains indicated a 0-10% mortality, L. serrana 20-80% and L. quasitownsendi 10-50%. With the modified WHO apparatus, the average mortality was < 4% for all species. No significant differences were observed among the paper treatments. These results indicate a strong species-specific effect of post-exposure conditions on sand flies. To establish baseline levels of insecticide resistance in Lutzomyia sand flies, the WHO method is recommended only for L. longipalpis, and the modified method for L. serrana, L. quasitownsendi and closely related species. PMID:12152485
Santamaría, Erika; Munstermann, Leonard E; Ferro, Cristina
The objective of this study was to carry out a taxonomic review of fossil American phlebotomine sand flies and describe two new species found in amber in the Dominican Republic. The gonostyle of one of these, Micropygomyia dorafeliciangeliae nov. sp., (= Lutzomyia dorafeliciangeliae, species group oswaldoi), has five spines, similar to that of Micropygomyia paterna (Quate, 1963) (= Lutzomyia paterna, species group oswaldoi), but they may be distinguished by the alpha/gamma ratio, which is < 1.0 in the new species and > 1 in the latter. Pintomyia dominicana nov. sp. (= Lutzomyia dominicana, species group verrucarum) has four spines on the gonostyle and presents a long bristle on the apex of the paramere, which distinguishes it from the other fossil species. With the description of these two new species, a total of 14 species of the American fossil phlebotomine sand flies has been described, 10 of which belong to the genus Pintomyia. An identification key for male fossil species is presented. PMID:19769025
Andrade Filho, José Dilermando; Galati, Eunice A Bianchi; Brazil, Reginaldo Peçanha
Two new rhabdoviruses, designated Carajas and Maraba, are described. Both were isolated from phlebotomine sand flies (Lutzomyia spp.) collected in the Amazon basin of Brazil. One recovery of Carajas virus was made from male sand flies. By complement-fixation and neutralization tests both agents were shown to be members of the vesicular stomatitis virus (VSV) serogroup (genus Vesiculovirus). The pathogenicity of the two viruses in mice and Vero cells is similar to that of VSV-Indiana and VSV-New Jersey. Both Carajas and Maraba viruses replicated in Lutzomyia longipalpis following intrathoracic inoculation, and both agents were transovarially transmitted in this sand fly species. PMID:6091472
Travassos da Rosa, A P; Tesh, R B; Travassos da Rosa, J F; Herve, J P; Main, A J
The number of recorded phlebotomine sand fly species in Ecuador has nearly doubled during the past 20 years as a result of surveys. In 2005, a sand fly survey of two localities, Tiputini in the Amazon rain forest and Paraiso Escondido in the Pacific coastal lowland forest, resulted in the capture of 25 species. New records for Ecuador consisted of five species from the Amazonian region and one from Paraiso Escondido. The Amazonian species were Nyssomyia richardwardi (Ready and Fraiha), Psathyromyia dreisbachi (Causey and Damasceno), Psathyromyia runoides (Fairchild and Hertig), Trichophoromyia pabloi (Barretto, Burbano and Young), and Trichopygomyia witoto (Young and Morales). The Pacific coastal lowland species was Psathyromyia punctigeniculata (Floch and Abonnenc).
Jones, Lynn A.; Cohnstaedt, Lee W.; Beati, Lorenza; Teran, Rommy; Leon, Renato; Munstermann, Leonard E.
Zoonotic visceral leishmaniasis (ZVL) is a serious public health problem in several Brazilian cities. Although the proximity of chicken houses is often cited as a risk factor in studies of urban ZVL, the role chickens play in the epidemiology of the disease has not been defined. Chickens attract both male and female sand flies (Lutzomyia longipalpis) but are unable to
Bruce Alexander; Renata Lopes de Carvalho; Hamish McCallum; Marcos Horácio Pereira
The Technical Bulletin on the bloodsucking psychodid flies of Columbia was made available in June, 1979. Two other papers, based on feild work near Manaus, Brazil in 1979,are in press. A proven vector of leishmaniasis, Lutzomyia wellcomei, and 39 other sp...
D. G. Young
A household vector control trial was carried out in the Peruvian Andes to measure the effect of spraying inside walls and ceilings with lambda-cyhalothrin on the risk for residents of cutaneous leishmaniasis caused by Leishmania peruviana. The mortality rates of Lutzomyia verrucarum measured with WHO contact bioassay cones set on adobe walls characteristic of the endemic region indicated an LD95
C. R. Davies; E. A. Llanos-Cuentas; P. Campos; J. Monge; E. Leon; J. Canales
Phylogenetic relationships among Phlebotominae were inferred through a pilot study using parsimony analysis of the D2 domain of ribosomal DNA sequences: 455 pairs of bases were sequenced in nine species of Phlebotomine sandflies which belong to the genera Lutzomyia, Phlebotomus and Sergentomyia. Two taxa are used as outgroups: Psychoda sp. and Nemapalpus flavus which is the sister group of the
Jérôme Depaquit; Sylvie Perrotey; Guillaume Lecointre; Annie Tillier; Simon Tillier; Hubert Ferté; Matthieu Kaltenbach; Nicole Léger
Urbanization and vector domestication are currently proposed as factors that contributed to the recent increase of American cutaneous leishmaniasis (ACL). Is likely also urban transmission? Oran is the main city in the Argentinean hyper-endemic area of ACL, and human cases in urban residences are usually reported. In order to assess the spatial distribution of risk, phlebotomine traps were located in different environments of Oran. A total of 7,787 sand flies were captured: Lutzomyia neivai (98.1%), Lutzomyia migonei (1.2%), Lutzomyia cortelezzii (0.7%), and one Lutzomyia shannoni. During the season of transmission (April-May) a single sand fly was obtained in one out of five urban sites, while a trap in a peri-urban pigsty captured up to 2,985 Lu. neivai/night. Captures performed in the other season of vector activity (September-October) revealed that small-scale changes in the pigsty environment resulted in noticeable changes in the abundance of Lu. neivai. In addition, in a new neighbourhood, on the fringe of the city, 1,073 Lu. neivai/site were captured in the forested edge but one in the yard of the houses. Therefore, in this urban ACL focus the human-vector effective contact risk is still associated with peri-urban vegetation and ecotone modifications despite the urban residence of the cases. PMID:18545855
Salomón, Oscar D; Quintana, María G; Zaidenberg, Mario
Two species of sandflies (Lutzomyia) are competent vectors of Plasmodium mexicanum, a malaria parasite of lizards. The very patchy distribution of sites with high P. mexicanum prevalence in the lizards, and often low or even nil sandfly density at such sites, provoked an evaluation of 2 common lizard ectoparasites, the tick Ixodes pacificus and the mite Geckobiella occidentalis, as potential
Jos. J. Schall; Thomas C. Smith
The group of diseases known as the leishmaniases are caused by obligate intracellular protozoa of the genus Leish- mania (39). Natural transmission of leishmania is carried out by a certain species of sandfly of the genus Phlebotomus (Old World) or Lutzomyia (New World). These are present in three different forms: (i) visceral leishmaniasis (VL), (ii) cutaneous leishmaniasis, and (iii) mucocutaneous
Shyam Sundar; M. Rai
Phylogenetic relationships among Phlebotominae were inferred through a pilot study using parsimony analysis of the D2 domain of ribosomal DNA sequences: 455 pairs of bases were sequenced in nine species of Phlebotomine sandflies which belong to the genera Lutzomyia, Phlebotomus and Sergentomyia. Two taxa are used as outgroups: Psychoda sp. and Nemapalpus flavus which is the sister group of the Phlebotominae. The South American genus Lutzomyia appears to be monophyletic. The Mediterranean species Sergentomyia dentata is its sister group and is not clustered with the Old World genus Phlebotomus. The latter is a paraphyletic genus with an early individualization of the branch including the closely related subgenera Phlebotomus and Paraphlebotomus, and a late individualization of the subgenus Larroussius. These results have some consequences on the biogeography of the leishmaniasis in the Old World. PMID:9835021
Depaquit, J; Perrotey, S; Lecointre, G; Tillier, A; Tillier, S; Ferté, H; Kaltenbach, M; Léger, N
In this study, we compare the development of infection and\\/or disease in Beagle dogs intradermally infected with Leishmania chagasi, in the presence or absence of Lutzomyia longipalpis saliva, with those of intravenously infected animals.Spleen samples of all the animals inoculated with parasites had positive polymerase chain reaction tests for Leishmania DNA. Positive spleen cultures for Leishmania were detected earlier (P?0.018)
Moacir Paranhos-Silva; Geraldo G. S. Oliveira; Eliana A. Reis; Rejane M. C. de Menezes; Octávio Fernandes; Ítalo Sherlock; Regis B. B. Gomes; Lain C. Pontes-de-Carvalho; Washington L. C. dos-Santos
In Colombia, the entomopathogenic fungusBeauveria bassiana(Deuteromycotina: Hyphomycetes) is widely used to control the coffee berry borerHypothenemus hampei(Coleoptera: Scolytidae) in coffee plantations. Recent studies suggested that this fungus is also pathogenic to several important vectors of disease, includingPhlebotomus papatasiandLutzomyia longipalpis(Diptera: Psychodidae). The present study evaluated the use ofB. bassianaas a potential biological control agent against phlebotomine sand flies in Colombian coffee
Richard Reithinger; Clive R. Davies; Horacio Cadena; Bruce Alexander
The article presents a synthesis of present knowledge concerning sandflies of the family Phlebotomidae in relation to leishmaniasis. Over 500 species of Phlebotominae are known, most of which belong to the genera Phlebotomus and Sergentomyia in the Old World and Lutzomyia in the New World. Phlebotomus is the dominant genus in the palaearctic region, extending also into the other regions of the Old World where Sergentomyia is the principal genus. Sandflies are of little importance in temperate North America but in tropical America Lutzomyia is the main genus and is found over large areas. The distribution of sandflies largely determines the occurrence of leishmaniasis. Certain species of Phlebotomus and Lutzomyia transmit dermal leishmaniasis in large areas of the palaearctic and neotropical regions. Visceral leishmaniasis is transmitted by some species of Phlebotomus in much of the palaearctic region, except desert areas of North Africa, and in limited areas of Africa and India, and by a species of Lutzomyia in north-eastern Brazil. Sandflies are quite likely to bite man in the open country of much of the Old World; they tend however to be localized in distribution on account of their need for a suitable microhabitat (e.g., the burrow of the Central Asian large gerbil, which has been extensively studied in relation to dermal leishmaniasis). It is noted that the distribution of sandflies and leishmaniasis appears to be changing. A few species of sandfly are regarded as proved vectors of human leishmaniasis according to five criteria; other species which are the only man-biting sandflies in the area are probably vectors. Although it is not possible to make a clear-cut list of vectors, a table of some proved and suspected vectors is included.
Lewis, D. J.
The number of recorded phlebotomine sand fly species in Ecuador has nearly doubled during the past 20 years as a result of surveys. In 2005, a sand fly survey of two localities, Tiputini in the Amazon rain forest and Paraiso Escondido in the Pacific coastal lowland forest, resulted in the capture of 25 species. New records for Ecuador consisted of five species from the Amazonian region and one from Paraiso Escondido. The Amazonian species were Nyssomyia richardwardi (Ready and Fraiha), Psathyromyia dreisbachi (Causey and Damasceno), Psathyromyia runoides (Fairchild and Hertig), Trichophoromyia pabloi (Barretto, Burbano and Young), and Trichopygomyia witoto (Young and Morales). The Pacific coastal lowland species was Psathyromyia punctigeniculata (Floch and Abonnenc). PMID:22628901
Jones, Lynn A; Cohnstaedt, Lee W; Beati, Lorenza; Terán, Rommy; León, Renato; Munstermann, Leonard E
Due to the occurrence of cases of dermal leishmaniasis in the Municipality of Piçarras, in the East of the Brazilian State of Santa Catarina, collections of Phlebotomine sandflies by the use of CDC-like light traps were developed near the houses of the patients. Three species (Lutzomyia neivai, Lu. fischeri and Lu. ayrozai) were collected. Lu. neivai was predominant near the houses, and Lu. ayrozai was collected in a secondary forest in a nearby municipality (Navegantes). The novelty of this focus, the most southern one in the East of Brazil, underscores the need for more complete studies on the sandfly fauna. PMID:16082487
Marcondes, Carlos Brisola; Conceição, Maria Bernadete E; Portes, Maria Graça T; Simão, Bento P
Genomic and antigenic characterization of Aguacate virus, a tentative species of the genus Phlebovirus, and three other unclassified viruses, Armero virus, Durania virus and Ixcanal virus, demonstrate a close relationship to one another. They are distinct from the other nine recognized species within the genus Phlebovirus. We propose to designate them as a new (tenth) serogroup or species (Aguacate virus) within the genus. The four viruses were all isolated from phlebotomine sandflies (Lutzomyia sp.) collected in Central and South America. Aguacate virus appears to be a natural reassortant and serves as one more example of the high frequency of reassortment in this genus. PMID:21325481
Palacios, Gustavo; da Rosa, Amelia Travassos; Savji, Nazir; Sze, Wilson; Wick, Ivan; Guzman, Hilda; Hutchison, Stephen; Tesh, Robert; Lipkin, W Ian
Genomic and antigenic characterization of Aguacate virus, a tentative species of the genus Phlebovirus, and three other unclassified viruses, Armero virus, Durania virus and Ixcanal virus, demonstrate a close relationship to one another. They are distinct from the other nine recognized species within the genus Phlebovirus. We propose to designate them as a new (tenth) serogroup or species (Aguacate virus) within the genus. The four viruses were all isolated from phlebotomine sandflies (Lutzomyia sp.) collected in Central and South America. Aguacate virus appears to be a natural reassortant and serves as one more example of the high frequency of reassortment in this genus.
Travassos da Rosa, Amelia; Savji, Nazir; Sze, Wilson; Wick, Ivan; Guzman, Hilda; Hutchison, Stephen; Tesh, Robert; Lipkin, W. Ian
The natural infection of sand flies by Leishmania species was studied in the Andean areas of Peru where cutaneous leishmaniasis caused by Leishmania (Viannia) peruviana is endemic. Sand flies were captured by human bait and Center for Disease Control (CDC) light trap catches at Nambuque and Padregual, Department of La Libertad, Peru, and morphologically identified. Among 377 female sand flies dissected, the two dominant man-biting species were Lutzomyia (Helcocyrtomyia) peruensis (211 flies) and Lutzomyia (Helcocyrtomyia) caballeroi (151 flies). Another sand fly species captured by light trap was Warileya phlebotomanica (15 flies). The natural infection of sand flies by flagellates was detected in 1.4% of Lu. (H.) peruensis and 2.6% of Lu. (H.) caballeroi, and the parasite species were identified as Le. (V.) peruviana and Trypanosoma avium, respectively, by molecular biological methods. The results indicated that the vector species responsible for the transmission of leishmaniasis in the study areas is Lu. (H.) peruensis. In addition, the presence of Trypanosoma in man-biting sand fly species means that more careful consideration is necessary for vector research in areas of Andean Peru where leishmaniasis is endemic. PMID:20954867
Kato, Hirotomo; Gomez, Eduardo A; Cáceres, Abraham G; Vargas, Franklin; Mimori, Tatsuyuki; Yamamoto, Kento; Iwata, Hiroyuki; Korenaga, Masataka; Velez, Lenin; Hashiguchi, Yoshihisa
An intraspecific study on Phlebotomus papatasi, the main proven vector of Leishmania major among the members of the subgenus Phlebotomus, was performed. The internal transcribed spacer 2 (ITS 2) of rDNA and the ND4 gene of mt DNA were sequenced from 26 populations from 18 countries (Albania, Algeria, Cyprus, Egypt, Greece, India, Iran, Israel, Italy, Lebanon, Morocco, Saudi Arabia, Spain, Syria, Tunisia, Turkey, Yugoslavia and Yemen), and compared. Samples also included three other species belonging to the subgenus Phlebotomus: P. duboscqi, a proven vector of L. major in the south of Sahara (three populations from Burkina Faso, Kenya and Senegal), P. bergeroti, a suspected vector of L. major (three populations from Oman Sultanate, Iran and Egypt), and one population of P. salehi from Iran. A phylogenetic study was carried out on the subgenus Phlebotomus. Our results confirm the validity of the morphologically characterized taxa. The position of P. salehi is doubtful. Variability in P. papatasi contrasts with that observed within other species having a wide distribution like P. (Paraphlebotomus) sergenti in the Old World or Lutzomyia (Lutzomyia) longipalpis in the New World. Consequently, it could be hypothesized that all populations of P. papatasi over its distribution area have similar vectorial capacities. The limits of the distribution area of L. major are correlated with the distribution of common rodents acting as hosts of the parasites. PMID:18243814
Depaquit, Jérôme; Lienard, Emmanuel; Verzeaux-Griffon, Astrid; Ferté, Hubert; Bounamous, Azzedine; Gantier, Jean-Charles; Hanafi, Hanafi A; Jacobson, Raymond L; Maroli, Michele; Moin-Vaziri, Vahideh; Müller, Frédérique; Ozbel, Yusuf; Svobodova, Milena; Volf, Petr; Léger, Nicole
Infections of the lizard malaria parasite Plasmodium mexicanum are often genetically complex within their fence lizard host (Sceloporus occidentalis) harbouring two or more clones of parasite. The role of clonal diversity in transmission success was studied for P. mexicanum by feeding its sandfly vectors (Lutzomyia vexator and Lutzomyia stewarti) on experimentally infected lizards. Experimental infections consisted of one, two, three or more clones, assessed using three microsatellite markers. After 5days, vectors were dissected to assess infection status, oocyst burden and genetic composition of the oocysts. A high proportion (92%) of sandflies became infected and carried high oocyst burdens (mean of 56 oocysts) with no influence of clonal diversity on these two measures of transmission success. Gametocytemia was positively correlated with transmission success and the more common vector (L. vexator) developed more oocysts on midguts. A high proportion ( approximately 74%) of all alleles detected in the lizard blood was found in infected vectors. The relative proportion of clones within mixed infections, determined by peak heights on pherograms produced by the genetic analyser instrument, was very similar for the lizard's blood and infections in the vectors. These results demonstrate that P. mexicanum achieves high transmission success, with most clones making the transition from vertebrate-to-insect host, and thus explains in part the high genetic diversity of the parasite among all hosts at the study site. PMID:19523471
Vardo-Zalik, A M
American cutaneous leishmaniasis acquired epidemic characteristics on the northern coastline of the State of São Paulo beginning in the 1990s. From secondary data, a descriptive study of the disease in the four municipalities making up this region over the period from 1993 to 2005 was conducted. The frequency of phlebotomine capture in the probable transmission locations was analyzed. 689 autochthonous cases of cutaneous leishmaniasis were notified, with single and grouped cases, thus determining that the spatial distribution was heterogenous. There was synchronism and cyclicity of disease manifestation, at intervals of six to eight years. All ages were affected, with slight predominance among males, without association with any specific occupation. Among the 2,758 phlebotomines captured, Nyssomyia intermedia predominated (80.4%) inside homes and in areas surrounding them. The disease presented a transmission profile inside homes and in areas surrounding them, between the urban fringe and forests, and inside forests. In such cases, transmission would be more related to enzootic foci. PMID:19142444
Condino, Maria Lúcia Fadel; Galati, Eunice Aparecida Bianchi; Holcman, Márcia Moreira; Salum, Maria Rafaela Braga; Silva, Diogo Correa da; Novaes Júnior, René Antonio
The environmental factors that contribute to the development of autoimmune diseases are largely unknown. Endemic pemphigus foliaceus in humans, known as Fogo Selvagem (FS) in Brazil, is mediated by pathogenic IgG4 autoantibodies against desmoglein1 (Dsg1). Clusters of FS overlap with those of leishmaniasis, a disease transmitted by sand fly (Lutzomyia longipalpis) bites. In this study we show that salivary antigens from the sand fly, and specifically the LJM11 salivary protein, are recognized by FS antibodies. Anti-Dsg1 monoclonal autoantibodies derived from FS patients also cross-react with LJM11. Mice immunized with LJM11 generate anti-Dsg1 antibodies. Thus, insect bites may deliver salivary antigens that initiate a cross-reactive IgG4 antibody response in genetically susceptible individuals and lead to subsequent FS. Our findings establish a clear relationship between an environmental, non-infectious antigen and the development of potentially pathogenic autoantibodies in an autoimmune disease.
Qian, Ye; Jeong, Joseph S.; Maldonado, Mike; Valenzuela, Jesus G.; Gomes, Regis; Evangelista, Flor; Qaqish, Bahjat; Aoki, Valeria; Hans, Gunter; Rivitti, Evandro A.; Eaton, Donald; Diaz, Luis A.
The 12th annual Latin American symposium presented by the American Mosquito Control Association (AMCA) was held as part of the 68th Annual Meeting in Denver, CO, in February 2002. The principal objective, as for the previous 11 symposia, was to promote participation in the AMCA by vector control specialists, public health workers, and academicians from Latin America. This publication includes summaries of 35 presentations that were given orally in Spanish or presented as posters by participants from 7 countries in Latin America. Topics addressed in the symposium included results from chemical and biological control programs and studies; studies of insecticide resistance; and population genetics, molecular, ecological, and behavioral studies of vectors of dengue (Aedes aegypti and Aedes albopictus) and other arboviruses, malaria (Anopheles albimanus and Anopheles pseudopunctipennis), leishmaniasis (Lutzomyia), and Chagas Disease (Triatoma). Related topics included biology and control of Culiseta inornata, Ochlerotatus taeniorhynchus, scorpions, Chironomus plumosus, and Musca domestica. PMID:12322934
Clark, Gary G; Martínez, Humberto Quiroz
The 15th Annual Latin American symposium presented by the American Mosquito Control Association (AMCA) was held as part of the 71st Annual Meeting in Vancouver, British Columbia, Canada, in April 2005. The principal objective, as for the previous 14 symposia, was to promote participation in the AMCA by vector control specialists, public health workers, and academicians from Latin America. This publication includes summaries of 40 presentations that were given orally in Spanish or presented as posters by participants from 8 countries in Latin America and the USA. Topics addressed in the symposium included results from chemical and biological control programs and studies; studies of insecticide resistance; and population genetics, molecular, ecological, and behavioral studies of vectors of dengue (Aedes aegypti and Ae. albopictus) and other arboviruses, malaria (Anopheles albimanus, An. aquasalis, An. neomaculipalpus, An. pseudopunctipennis), leishmaniasis (Lutzomyia), and Chagas Disease (Triatoma), as well as a vaccine for control of Boophilus ticks on cattle. PMID:16570381
Clark, Gary G; Quiroz Martínez, Humberto
The 14th annual Latin American symposium presented by the American Mosquito Control Association (AMCA) was held as part of the 70th Annual Meeting in Savannah, GA, in February 2004. The principal objective, as for the previous 13 symposia, was to promote participation in the AMCA by vector control specialists, public health workers, and academicians from Latin America. This publication includes summaries of 37 presentations that were given orally in Spanish or presented as posters by participants from 7 countries in Latin America. Topics addressed in the symposium included results from chemical and biological control programs and studies; studies of insecticide resistance; and population genetics, molecular, ecological, and behavioral studies of vectors of dengue (Aedes aegypti and Aedes albopictus) and other arboviruses, malaria (Anopheles albimanus and Anopheles pseudopunctipennis), leishmaniasis (Lutzomyia), and Chagas disease (Triatoma). PMID:15669378
Clark, Gary G; Quiroz Martínez, Humberto
A study of the natural infection of phlebotomine sand flies by Leishmania (Leishmania) infantum was conducted in an area of visceral leishmaniasis in São Vicente Férrer, located in the northern part of the Atlantic rain forest region in the State of Pernambuco, Brazil. In a previous study, Migonemyia migonei have been found predominantly in peridomiciles and houses in this endemic area. The analysis of M. migonei, collected by CDC light trap, by multiplex PCR assay coupled to non-isotopic hybridization showed that 2 females out of 50 were infected by L. infantum. This is the first finding of natural infection of M. migonei by L. infantum suggesting that M. migonei may be the vector of L. infantum in areas of visceral leishmaniasis where Lutzomyia longipalpis, the usual vector, is absent. PMID:20457120
de Carvalho, Maria Rosimery; Valença, Helio França; da Silva, Fernando José; de Pita-Pereira, Daniela; de Araújo Pereira, Thaís; Britto, Constança; Brazil, Reginaldo Peçanha; Brandão Filho, Sinval Pinto
The environmental changes resulting from the construction of hydroelectric dams may affect the fauna of insect vectors and consequently the epidemiology of the diseases they transmit. This work examined the mosquito and sand fly fauna in the area of the Aimorés hydroelectric power plant, analyzing the seasonal distribution and the degree of species synanthropy in different ecotopes. Between November, 2008 and September, 2009, entomological captures were performed with the help of HP light traps in the rural, urban, and forest areas of Aimorés, Ituêta, Resplendor, and Baixo Guandu counties. The fauna proved to be quite diversified. Twenty-two species of mosquitoes and 11 species of sand flies were found. Culex quinquefasciatus was predominant among mosquitoes (76.7%), while Lutzomyia intermedia prevailed among sand flies (34.5%). Some of the captured species have medical interest. Supported by the high degree of synanthropy, those species reinforce the need for epidemiological surveillance. PMID:23181864
Barata, R A; Ursine, R L; Nunes, F P; Morais, D H; Araújo, H S
The aim of this study was to analyze the magnitude and trend of American Tegumentary Leishmaniasis (ATL) in the State of São Paulo from 1975 to 2008. An ecological study that classified municipalities according to the magnitude of transmission was performed. From 1975 to 1985, 1,281 cases of ATL were registered in 45 municipalities, rising to 258 municipalities and 4,093 cases from 1986 to 1995; and reaching 385 municipalities and 7,604 cases from 1996 to 2008. Lutzomyia intermedia s.l. was collected in most of the entomological surveys. In the classification of municipalities according to magnitude, 67.5% were observed to have a "small magnitude," 19.2% "moderate magnitude" and 13.3% "high magnitude." The highest incidences of ATL have been restricted to underserved areas close to the Atlantic forest. There was an increase in the number of municipalities with small occurrence of cases and expansion in the area of risk. PMID:23090308
da Silva, Rubens Antonio; Mercado, Vanessa Taís Cruz; Henriques, Lúcia de Fátima; Ciaravolo, Ricardo Mário de Carvalho; Wanderley, Dalva Marli Valério
American cutaneous leishmaniasis (ACL) is a focal disease whose surveillance and control require complex actions. The present study aimed to apply integrated tools related to entomological surveillance, environmental management, and health education practices in an ACL-endemic area in Rio de Janeiro city, RJ, Brazil. The distribution of the disease, the particular characteristics of the localities, and entomological data were used as additional information about ACL determinants. Environmental management actions were evaluated after health education practices. The frequency of ACL vectors Lutzomyia (N.) intermedia and L. migonei inside and outside houses varied according to environment characteristics, probably influenced by the way of life of the popular groups. In this kind of situation environmental management and community mobilization become essential, as they help both specialists and residents create strategies that can interfere in the dynamics of vector's population and the contact between man and vectors. PMID:22988458
Gouveia, Cheryl; de Oliveira, Rosely Magalhães; Zwetsch, Adriana; Motta-Silva, Daniel; Carvalho, Bruno Moreira; de Santana, Antônio Ferreira; Rangel, Elizabeth Ferreira
Autochthonous human cases of leishmaniasis in the United States are uncommon. We report three new cases of cutaneous leishmaniasis and details of a previously reported case, all outside the known endemic range in Texas. Surveys for enzootic rodent reservoirs and sand fly vectors were conducted around the residences of three of the case-patients during the summer of 2006; female Lutzomyia anthophora sand flies were collected at a north Texas and southeast Oklahoma residence of a case-patient, indicating proximity of a suitable vector. Urban sprawl, climatologic variability, or natural expansion of Leishmania mexicana are possible explanations for the apparent spread to the north and east. Enhanced awareness among healthcare providers in the south central region of the United States is important to ensure clinical suspicion of leishmaniasis, diagnosis, and appropriate patient management. PMID:23185078
Clarke, Carmen F; Bradley, Kristy K; Wright, James H; Glowicz, Janet
This paper describes a series of experiments which were done to determine the behavior of 14 different phleboviruses in laboratory-reared sand flies (Phlebotomus papatasi, P. perniciosus and Lutzomyia longipalpis) after oral and parenteral infection. Most of the viruses replicated in the sand flies after intrathoracic inoculation; however, the insects were quite refractory to oral infection. Six of 11 phleboviruses tested were transovarially transmitted in one or more sand fly species. The percentage of infected F1 offspring produced by parenterally infected female parents ranged from 1.5-60%, depending on the virus type used. These data support the hypothesis that some of the phleboviruses are maintained in sand flies by transovarial transmission. PMID:6091466
Tesh, R B; Modi, G B
Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases. PMID:24069478
Moo-Llanes, David; Ibarra-Cerdeña, Carlos N; Rebollar-Téllez, Eduardo A; Ibáñez-Bernal, Sergio; González, Camila; Ramsey, Janine M
Leishmaniasis is a complex of zoonotic diseases that are endemic to many Brazilian states. They are transmitted to the vertebrates by the bite of the hematophagous female sand fly (Diptera: Psychodidae) vectors. Despite the increasing occurrence of visceral and cutaneous leishmaniasis cases in large urban centers, their transmission continues to occur primarily in a wild environment and may be associated with professional activities, ecotourism activities, or both. This study investigates the ecological parameters of the sand flies present in Ibitipoca State Park, Minas Gerais, Brazil. During 2009, systematic collections of sand flies were made monthly using HP light traps installed at five sites, including three natural settings (a cave, riparian vegetation, and a rain forest), the tourist and researchers' accommodations, and a surrounding domestic livestock area. In total, 161 sand flies (seven species) were collected, the most abundant, particularly in the surrounding domestic livestock area, being Lutzomyia (Psychodopygus) lloydi (Antunes, 1937). Furthermore, a previously unidentified Lutzomyia (Sciopemyia) sp. was prevalent in the cave environment. There are no existing records of the occurrence of leishmaniasis in Ibitipoca State Park; however, the some species of the subgenus Psychodopygus are known vectors of Leishmania spp in Brazil. Hence, the presence of a species of this genus in areas surrounding the park may represent a risk to ecotourism and the local inhabitants. Our study shows the importance of regular monitoring of the various areas used by humans to determine the distribution and spread of sand fly vectors for preventive management to forestall potential risk to health and consequent effect on ecotourists. PMID:21845934
Carvalho, Gustavo Mayr de Lima; De Vasconcelos, Fernanda Bernardes; Da Silva, Daniela Gonçalves; Botelho, Helbert Antônio; Filho, José Dilermando Andrade
Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases.
Moo-Llanes, David; Ibarra-Cerdena, Carlos N.; Rebollar-Tellez, Eduardo A.; Ibanez-Bernal, Sergio; Gonzalez, Camila; Ramsey, Janine M.
Interaction experiments between hematophagous insects and monoxenous trypanosomatids have become relevant, once cases of human infection involving these protozoa have been reported. Moreover, investigations related to the interaction of insects with trypanosomatids that harbour an endosymbiotic bacterium and thereby lack the paraflagellar rod structure are important to elucidate the role of this structure in the adhesion process. In this work, we compared the interaction of endosymbiont-bearing trypanosomatids and their aposymbiotic counterpart strains (without endosymbionts) with cell lines of Anopheles gambiae, Aedes albopictus and Lutzomyia longipalpis and with explanted guts of the respective insects. Endosymbiont-bearing strains interacted better with insect cells and guts when compared with aposymbiotic strains. In vitro binding assays revealed that the trypanosomatids interacted with the gut epithelial cells via flagellum and cell body. Flagella attached to the insect gut were enlarged, containing electrondense filaments between the axoneme and flagellar membrane at the point of adhesion. Interactions involving the flagellum lacking paraflagellar rod structure were mainly observed close to tight junctions, between epithelial cells. Endosymbiont-bearing trypanosomatids were able to colonise Aedes aegypti guts after protozoa feeding. PMID:13129523
Fampa, Patrícia; Corrêa-da-Silva, Miguel S; Lima, Dinair C; Oliveira, Sandra M P; Motta, Maria Cristina M; Saraiva, Elvira M B
Apyrases are enzymes that hydrolyze nucleotide di- and triphosphates to orthophosphate and mononucleotides. At least two families of enzymes, belonging to the 5'-nucleotidase and to the actin/heat shock 70/sugar kinase superfamily, have evolved independently to serve the apyrase reaction. Both families require either Ca(2+) or Mg(2+) for their action. A novel apyrase enzyme sequence, with no homology to any other known protein sequence, was found recently in the salivary glands of the hematophagous bed bug Cimex lectularius. This enzyme functions exclusively with Ca(2+). Here, we report the finding of a cDNA similar to that of the C. lectularius salivary apyrase isolated from a salivary gland cDNA library of Phlebotomus papatasi. Transfection of insect cells with the P. papatasi salivary gland apyrase cDNA resulted in the secretion of a Ca(2+)-dependent apyrase whose activity was indistinguishable from that in salivary homogenates of P. papatasi. Homologous sequences were found in humans, in another sand fly (Lutzomyia longipalpis), in the fruit fly Drosophila melanogaster, in the nematode Caenorhabditis elegans and in the protozoan Cryptosporidium parvum, indicating that this family of enzymes is widespread among animal species. PMID:11136609
Valenzuela, J G; Belkaid, Y; Rowton, E; Ribeiro, J M
Three strains of a trypanosomatid protozoan were isolated from the midguts of two naturally infected species of biting midges [Culicoides (Oecacta) festivipennis and Culicoides (Oecacta) truncorum] and characterized by light and electron microscopy and by molecular techniques. Morphological characteristics and sequences of the 18S rRNA, 5S rRNA, spliced leader RNA and glycosomal glyceraldehyde-3-phosphate dehydrogenase genes indicate that the studied flagellates represent a novel phylogenetic lineage within the Trypanosomatidae. Based on phylogenetic analyses, the novel endosymbiont-free, monoxenous trypanosomatid was classified as Sergeia podlipaevi gen. nov., sp. nov. Interestingly, it is closely related to another trypanosomatid species that parasitizes the sand fly Lutzomyia evansi, a blood-sucking dipteran from South America. The type strain of S. podlipaevi sp. nov., ICUL/CZ/2000/CER3, was obtained from Malpighian tubes. Of 2518 females of seven species of biting midges trapped in the Czech Republic, more than 1.5 % were infected by trypanosomatid parasites. An unrelated insect species, Culicoides (Monoculicoides) nubeculosus, was experimentally infected with S. podlipaevi, demonstrating that its host range extends to different subgenera of biting midges. PMID:17267991
Svobodová, Milena; Zídková, Lenka; Cepicka, Ivan; Oborník, Miroslav; Lukes, Julius; Votýpka, Jan
Background 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 L. major. Methods Females of laboratory-reared S. schwetzi were infected by cultured Leishmania spp. by feeding through a chicken membrane, dissected at different time intervals post bloodmeal and examined by light microscopy for the abundance and location of infections. Results All three Leishmania species produced heavy late stage infections in Lutzomyia longipalpis or Phlebotomus duboscqi sand flies used as positive controls. In contrast, none of them completed their developmental cycle in Sergentomyia females; Leishmania promastigotes developed within the bloodmeal enclosed by the peritrophic matrix (PM) but were defecated together with the blood remnants, failing to establish a midgut infection. In S. schwetzi, the PM persisted significantly longer than in L. longipalpis and it was degraded almost simultaneously with defecation. Therefore, Leishmania transformation from procyclic to long nectomonad forms was delayed and parasites did not attach to the midgut epithelium. Conclusions Sergentomyia schwetzi is refractory to human Leishmania species and the data indicate that the crucial aspect of the refractoriness is the relative timing of defecation versus PM degradation.
Phlebotomine vector ecology was studied in the largest recorded outbreak of American cutaneous leishmaniasis in Colombia in 2004. In two rural townships that had experienced contrasting patterns of case incidence, this study evaluated phlebotomine species composition, seasonal abundance, nocturnal activity, blood source, prevalence of Leishmania infection, and species identification. CDC miniature light traps were used to trap the phlebotomines. Traps were set indoors, peridomestically, and in woodlands. Natural infection was determined in pools by polymerase chain reaction–Southern blot, and blood sources and species identification were determined by sequencing. Large differences were observed in population abundance between the two townships evaluated. Lutzomyia longiflocosa was the most abundant species (83.1%). Abundance was higher during months with lower precipitation. Nocturnal activity was associated with human domestic activity. Blood sources identified were mainly human (85%). A high prevalence of infection was found in L. longiflocosa indoors (2.7%) and the peridomestic setting (2.5%). L. longiflocosa was responsible for domestic transmission in Chaparral.
Ferro, Cristina; Marin, Dairo; Gongora, Rafael; Carrasquilla, Maria C.; Trujillo, Jorge E.; Rueda, Norma K.; Marin, Jaime; Valderrama-Ardila, Carlos; Alexander, Neal; Perez, Mauricio; Munstermann, Leonard E.; Ocampo, Clara B.
Leishmaniases are a group of vector-borne diseases with different clinical manifestations caused by parasites transmitted by sand fly vectors. In Mexico, the sand fly Lutzomyia olmeca olmeca is the only vector proven to transmit the parasite Leishmania mexicana to humans, which causes leishmaniasis. Other vector species with potential medical importance have been obtained, but their geographic distributions and relation to transmission areas have never been assessed. We modeled the ecological niches of nine sand fly species and projected niches to estimate potential distributions by using known occurrences, environmental coverages, and the algorithms GARP and Maxent. All vector species were distributed in areas with known recurrent transmission, except for Lu. diabolica, which appeared to be related only to areas of occasional transmission in northern Mexico. The distribution of Lu. o. olmeca does not overlap with all reported cutaneous leishmaniasis cases, suggesting that Lu. cruciata and Lu. shannoni are likely also involved as primary vectors in those areas. Our study provides useful information of potential risk areas of leishmaniasis transmission in Mexico.
Gonzalez, Camila; Rebollar-Tellez, Eduardo A.; Ibanez-Bernal, Sergio; Becker-Fauser, Ingeborg; Martinez-Meyer, Enrique; Peterson, A. Townsend; Sanchez-Cordero, Victor
All natural Leishmania infections start in the skin; however, little is known of the contribution made by the sand fly vector to the earliest events in mammalian infection, especially in inflamed skin that can rapidly kill invading parasites. During transmission sand flies regurgitate a proteophosphoglycan gel synthesized by the parasites inside the fly midgut, termed promastigote secretory gel (PSG). Regurgitated PSG can exacerbate cutaneous leishmaniasis. Here, we show that the amount of Leishmania mexicana PSG regurgitated by Lutzomyia longipalpis sand flies is proportional to the size of its original midgut infection and the number of parasites transmitted. Furthermore, PSG could exacerbate cutaneous L. mexicana infection for a wide range of doses (10-10,000 parasites) and enhance infection by as early as 48 hours in inflamed dermal air pouches. This early exacerbation was attributed to two fundamental properties of PSG: Firstly, PSG powerfully recruited macrophages to the dermal site of infection within 24 hours. Secondly, PSG enhanced alternative activation and arginase activity of host macrophages, thereby increasing L-arginine catabolism and the synthesis of polyamines essential for intracellular parasite growth. The increase in arginase activity promoted the intracellular growth of L. mexicana within classically activated macrophages, and inhibition of macrophage arginase completely ablated the early exacerbatory properties of PSG in vitro and in vivo. Thus, PSG is an essential component of the infectious sand fly bite for the early establishment of Leishmania in skin, which should be considered when designing and screening therapies against leishmaniasis. PMID:19696894
Rogers, Matthew; Kropf, Pascale; Choi, Beak-San; Dillon, Rod; Podinovskaia, Maria; Bates, Paul; Müller, Ingrid
This study was developed in the urban area of Governador Valadares, a reemerging focus of intense transmission of visceral leishmaniasis (VL) in Brazil, presenting 86 human cases of VL from 2008 to 2011. The disease prevailed in males (73.2%) with most patients between 0 and 9 years (44.1%) and a lethality rate of 16.2%. A canine survey was carried out on 16,529 domestic dogs in 35 districts in the area and it showed that 30.2% of them (4,992?dogs) were positive for VL by serum assays. Prevalence ratios for canine VL varied between 13.6% and 53.4%. The clinical exam of 343 seropositive dogs showed that 49.9% of them were considered symptomatic, with larger prevalence of canine VL being in short-furred animals (90%). The entomological survey was performed in eight districts, where 2,539 phlebotomines were captured, preferentially in the peridomicile (84.5%). Lutzomyia longipalpis was the predominant species (90%) suggesting its participation in the VL transmission in the area. The correlation between canine prevalence and L. longipalpis density was evaluated.
Peixoto, Jennifer Cunha; Tanure, Aline; Gomes, Marcela Esteves; Apolinario, Estefania Conceicao; Bodevan, Emerson Cotta; de Araujo, Holbiano Saraiva; Dias, Edelberto Santos; Pinheiro, Aimara da Costa
A systematic review of the subgenus Paraphlebotomus (a group of phlebotomine sandflies which contains several vectors of leishmaniasis) is proposed. In the morphological approach, we study the available types and a lot of sandflies coming from different geographic areas. The taxonomic status of each species is revised. We consider P. marismortui as a synonym of P. alexandri. We suppose that P. mofidii is a valid species. P. similis is clearly differentiated from P. sergenti. A new species is described from North Africa: P. riouxi. We discuss the validity of P. saevus. Two molecular phylogenies based on ribosomal DNA sequences are proposed. The first one used the D2 domain of the 28 S sub-unit. It emphasises a very close relation between the subgenera Paraphlebotomus and Phlebotomus, a likely paraphyly of the genus Phlebotomus and the position of the genera Sergentomyia and Lutzomyia as two sister groups. The second one used the ITS 2. It emphasises the informative capacity of this gene for the resolution of the phylogenetic relations within the subgenera Paraphlebotomus. PMID:11060410
Depaquit, J; Ferté, H; Léger, N
All natural Leishmania infections start in the skin; however, little is known of the contribution made by the sand fly vector to the earliest events in mammalian infection, especially in inflamed skin that can rapidly kill invading parasites. During transmission sand flies regurgitate a proteophosphoglycan gel synthesized by the parasites inside the fly midgut, termed promastigote secretory gel (PSG). Regurgitated PSG can exacerbate cutaneous leishmaniasis. Here, we show that the amount of Leishmania mexicana PSG regurgitated by Lutzomyia longipalpis sand flies is proportional to the size of its original midgut infection and the number of parasites transmitted. Furthermore, PSG could exacerbate cutaneous L. mexicana infection for a wide range of doses (10–10,000 parasites) and enhance infection by as early as 48 hours in inflamed dermal air pouches. This early exacerbation was attributed to two fundamental properties of PSG: Firstly, PSG powerfully recruited macrophages to the dermal site of infection within 24 hours. Secondly, PSG enhanced alternative activation and arginase activity of host macrophages, thereby increasing L-arginine catabolism and the synthesis of polyamines essential for intracellular parasite growth. The increase in arginase activity promoted the intracellular growth of L. mexicana within classically activated macrophages, and inhibition of macrophage arginase completely ablated the early exacerbatory properties of PSG in vitro and in vivo. Thus, PSG is an essential component of the infectious sand fly bite for the early establishment of Leishmania in skin, which should be considered when designing and screening therapies against leishmaniasis.
Rogers, Matthew; Kropf, Pascale; Choi, Beak-San; Dillon, Rod; Podinovskaia, Maria; Bates, Paul; Muller, Ingrid
Background Bacteria associated with insects can have a substantial impact on the biology and life cycle of their host. The checkerboard DNA-DNA hybridization technique is a semi-quantitative technique that has been previously employed in odontology to detect and quantify a variety of bacterial species in dental samples. Here we tested the applicability of the checkerboard DNA-DNA hybridization technique to detect the presence of Aedes aegypti-associated bacterial species in larvae, pupae and adults of A. aegypti. Findings Using the checkerboard DNA-DNA hybridization technique we could detect and estimate the number of four bacterial species in total DNA samples extracted from A. aegypti single whole individuals and midguts. A. aegypti associated bacterial species were also detected in the midgut of four other insect species, Lutzomyia longipalpis, Drosophila melanogaster, Bradysia hygida and Apis mellifera. Conclusions Our results demonstrate that the checkerboard DNA-DNA hybridization technique can be employed to study the microbiota composition of mosquitoes. The method has the sensitivity to detect bacteria in single individuals, as well as in a single organ, and therefore can be employed to evaluate the differences in bacterial counts amongst individuals in a given mosquito population. We suggest that the checkerboard DNA-DNA hybridization technique is a straightforward technique that can be widely used for the characterization of the microbiota in mosquito populations.
Leishmaniasis is endemic since last century in Adrianópolis Municipality, Ribeira Valley and is a serious public health. A study carried out during 1993-2003 on epidemiological surveys conducted in rural communities showed 339 new cases of cutaneous leishmaniasis (CL) detected from four municipalities (Adrianópolis, Cerro Azul, Doutor Ulysses and Rio Branco do Sul). A larger prevalence of cutaneous lesions was observed in rural workers (36%), women with domestic activities (18%), and younger students (31%). Multiple lesions were noticed in 53% of patients, but only one case of mucocutaneous leishmaniasis was reported. Twenty stocks were isolated from patients with characteristics lesions and were identified as Leishmania (Viannia) braziliensis using multi-locus enzyme electrophoresis (MLEE) and Random Amplified DNA (RAPD). In Phlebotominae survey, five species were obtained. Lutzomyia intermedia sl. represented 97.5% in peridomiciliar area and 100% in domicile. A canine serological survey made (Indirect Immunofluorescence Antibody Test, IFAT and Enzyme Linked Immunosorbent Assay, ELISA) in six rural county of Adrianópolis Municipality during 1998-1999 showed that 15.1% (24/159) of dogs were sera reactive. No lesions were observed in dogs and no parasite was isolated from lymph node aspirates and biopsies. In wild reservoirs study, only seven animals (Cricetidae, Desmodus sp. and edentates) were captured, but no parasites were found in culture from deep organs. The paper presents results of our 10 years study on cutaneous leishmaniasis survey in the Ribeira River Valley, East Region of Paraná State, Brazil. Environment changes in this region are also discussed. PMID:15652328
de Castro, Edilene Alcântara; Luz, Ennio; Telles, Flávio Queiroz; Pandey, Ashok; Biseto, Alceu; Dinaiski, Marlene; Sbalqueiro, Ives; Soccol, Vanete Thomaz
An American cutaneous leishmaniasis outbreak, with cases clustering during 1993 in Tartagal city, Salta, was reported. The outbreak involved 102 individuals, 43.1% of them with multiple ulcers. Age (mean: 33 years old) and sex distribution of cases (74.5% males), as well as working activity (70 forest-related), support the hypothesis of classical forest transmission leishmaniasis, despite the fact that the place of permanent residence was in periurban Tartagal. Moreover, during July, sandflies were only collected from one of the 'deforestation areas'. Lutzomyia intermedia was the single species of the 491 phlebotomines captured, reinforcing the vector incrimination of this species. Most infections must have been acquired during the fall (April to June), a pattern consistent with previous sandfly population dynamics data. Based on the epidemiological and entomological results, it was advised not to do any vector-targeted periurban control measures during July. Further studies should be done to assess if the high rate of multiple lesions was due to parasite factors or to infective vector density factors. PMID:11340485
Salomon, O D; Zaidenberg, M; Burgos, R; Heredia, V I; Caropresi, S L
Leishmania vaccines that protect against needle challenge fail against the potency of a Leishmania-infected sand fly transmission. Here, we demonstrate that intradermal immunization of mice with 500?ng of the sand fly salivary recombinant protein LJM11 (rLJM11) from Lutzomyia longipalpis, in the absence of adjuvant, induces long-lasting immunity that results in ulcer-free protection against Leishmania major delivered by vector bites. This protection is antibody independent and abrogated by depletion of CD4+ T cells. Two weeks after challenge, early induction of IFN-? specifically to rLJM11 correlates to diminished parasite replication in protected animals. At this time point, Leishmania-specific induction of IFN-? in these mice is low in comparison with its high level in non-protected controls. We hypothesize that early control of parasites in a T-cell helper type 1 environment induced by immunity to LJM11 permits the slow development of Leishmania-specific immunity in the absence of open ulcers. Leishmania-specific immunity observed 5 weeks after infection in rLJM11-immunized mice shows a twofold increase over controls in the percentage of IFN-?-producing CD4+ T cells. We propose LJM11 as an immunomodulator that drives an efficient and controlled protective immune response to a sand fly–transmitted Leishmania somewhat mimicking “leishmanization”-induced protective immunity but without its associated lesions.
Gomes, Regis; Oliveira, Fabiano; Teixeira, Clarissa; Meneses, Claudio; Gilmore, Dana C; Elnaiem, Dia-Eldin; Kamhawi, Shaden; Valenzuela, Jesus G
Synthetic blends of chemicals identified previously from human skin emanations were evaluated against mosquito and biting fly populations at the Lower Suwannee Wildlife Refuge near Cedar Key, FL. Mosquito Magnet-Experimental traps were baited with the Red (400 ml acetone: 10 ml 1-hexen-3-ol:10 ml 1-octen-3-ol), Blue (400 ml acetone: 1 g/liter lactic acid:20 ml glycolic acid), or Green blend (400 ml acetone:1.5 g/liter lactic acid:20 ml dimethyl disulfide) plus CO2 or with CO2 alone (control). A relative index of efficacy was determined by dividing each mean blend trap catch by the mean control trap catch. Five mosquitoes (Aedes infirmatus, Ae. taeniorhynchus, Ae. triseriatus, Anopheles crucians, and Culex nigripalpus), 2 ceratopogonid (Culicoides floridensis and C. furens), and 1 tabanid (Diachlorus ferrugatus) and phlebotomine (Lutzomyia shannoni) species were trapped. The Red blend + CO2 treatment significantly increased collections of Ae. taeniorhynchus (3.4x), An. crucians (2.8X), total mosquitoes (2.7x), C. furens (17.6x), and L. shannoni (10.8x) compared with control traps. Traps baited with either the Blue or Green blends generally captured fewer insects than traps baited with the other 2 treatments. However, traps baited with the Green blend caught 7 x as many C. furens as the control traps. Responses clearly varied according to species; therefore, "one size does not fit all" when it comes to attractant blends. PMID:22894125
Kline, Daniel L; Bernier, Ulrich R; Hogsette, Jerome A
A review of the literature regarding bartonellosis or Carrion's disease in Colombia and Ecuador is presented, together with observations made by the author in areas of both countries from which the disease has been recorded. There is evidence from pre-Columbian artifacts that verruga peruana, the cutaneous form of the disease, was present in Ecuador at least 1,000 years prior to the arrival of Europeans. These artifacts were discovered in the coastal province of Manabi, a low-lying area very different from the high Andean valleys of Peru with which bartonellosis is normally associated. Most of the cases recorded in recent years from this coastal area. The disease does not appear to have occurred in Colombia before the 1930s and only one case has been reported during the past 40 years. The possibility of many more subclinical cases being present in both Ecuador and Colombia is discussed, together with the possibility that the acquired immunodeficiency syndrome epidemic will reveal a higher prevalence among the inhabitants of endemic areas than previously suspected. Although the suspected vector of Bartonella bacilliformis, the sand fly Lutzomyia verrucarum, has not been recorded from Ecuador or Colombia, related species are present in endemic areas and may be involved in transmission. PMID:7741177
The life-cycle of Plasmodium depends on transmission of the parasite from the vertebrate host into its vector when the insect takes a bloodmeal. Transmission success may depend in part on the parasite's gametocyte density and sex ratio in the blood. P. mexicanum, a parasite of fence lizards in California, USA, exploits the sandfly Lutzomyia vexator as its vector. In experimental transmissions using naturally infected lizards as donors of blood, transmission success (measured as percentage of vectors infected and number of parasite oocysts on the insect's midgut) was positively related to gametocyte density, although density above 20/1000 erythrocytes did not improve transmission. Sex ratio (proportion of microgametocytes in the infection) was positively correlated with gametocyte density. Transmission improved with higher proportion of microgametocytes, but partial correlations revealed that this was a result only of higher gametocyte densities. These results agree with the theory of virulence and sex ratios because single clone infections should produce a more female-biased sex ratio and grow to the minimum parasitaemia that would maximize clonal transmission, whereas multiple clone infections will be closer to a 1:1 sex ratio and yield a higher parasitaemia when each clone competes for transmission to the vector. PMID:11155927
Schall, J J
Two species of sandflies (Lutzomyia) are competent vectors of Plasmodium mexicanum, a malaria parasite of lizards. The very patchy distribution of sites with high P. mexicanum prevalence in the lizards, and often low or even nil sandfly density at such sites, provoked an evaluation of 2 common lizard ectoparasites, the tick Ixodes pacificus and the mite Geckobiella occidentalis, as potential passive vectors. Plasmodium sp.-specific polymerase chain primers were used to amplify a long segment of the mitochondrial cytochrome b gene that is unlikely to survive intact if the parasite cells are killed within a blood-feeding arthropod. The segment was strongly amplified from sandflies (the positive control for the method) from 1 to 96 hr postfeeding on an infected lizard. For ticks, the gene fragment was poorly amplified at 0 hr postfeed, and not amplified after 2 hr. In contrast, strong amplification of the parasite DNA was observed from mites from 0 to 20 hr postfeed, and weak amplification even at 96 hr. PMID:16729709
Schall, Jos J; Smith, Thomas C
Chitinases of trypanosomatid parasites have been proposed to fulfil various roles in their blood-feeding arthropod vectors but so far none have been directly tested using a molecular approach. We characterized the ability of Leishmania mexicana episomally transfected with LmexCht1 (the L. mexicana chitinase gene) to survive and grow within the permissive sand fly vector, Lutzomyia longipalpis. Compared with control plasmid transfectants, the overexpression of chitinase was found to increase the average number of parasites per sand fly and accelerate the escape of parasites from the peritrophic matrix-enclosed blood meal as revealed by earlier arrival at the stomodeal valve. Such flies also exhibited increased damage to the structure of the stomodeal valve, which may facilitate transmission by regurgitation. When exposed individually to BALB/c mice, those flies with chitinase-overexpressing parasites spent on average 2.4–2.5 times longer in contact with their host during feeding, compared with flies with control infections. Furthermore, the lesions that resulted from these single fly bite infections were both significantly larger and with higher final parasite burdens than controls. These data show that chitinase is a multifunctional virulence factor for L. mexicana which assists its survival in Lu. longipalpis. Specifically, this enzyme enables the parasites to colonize the anterior midgut of the sand fly more quickly, modify the sand fly stomodeal valve and affect its blood feeding, all of which combine to enhance transmission.
Rogers, Matthew E; Hajmova, Martina; Joshi, Manju B; Sadlova, Jovana; Dwyer, Dennis M; Volf, Petr; Bates, Paul A
Background Insecticide thermal fogging (ITF) is a tool to control vector borne diseases. Insecticide application success for vector control has been associated with housing materials and architecture. Vector abundance is correlated with weather changes. Nevertheless, housing quality and weather impacts on vector abundance have been unaccounted for in most New World insecticide control trials for leishmaniasis vectors. Methods We conducted a 15 month insecticide control trial that included two deltamethrin [6 mg a.i.m-2] based ITF interventions in 12 of 24 monitored houses at Trinidad de Las Minas, a hyperendemic cutaneous leishmaniasis transmission village in western Panamá. During the study we followed sand fly (SF) abundance, keeping track of rainfall and quantified housing quality using an index based on architecture and construction materials. Results We found a 50 to 80% reduction in SF density in the fogged houses when compared with control houses, while controlling for seasonal changes in SF abundance associated with rainfall. We found heterogeneities in the reductions, as abundance changed according to SF species: Lutzomyia gomezi, Lu. panamensis, Lu. dysponeta and Lu. triramula reduced in density between 40% and 90% after ITF. In contrast, Lu. trapidoi density increased 5% after ITF. Differences in the impact of ITF were associated with housing quality, the most destitute houses, i.e., those with features that ease insect entrance, had a disproportionally larger SF abundance, in some cases with increased domiciliary SF density following the ITF. Conclusion Our results suggest the potential of insecticide application to control SF density and leishmaniasis transmission could depend on housing quality beyond insecticide efficiency.
Leishmania infantum is the etiologic agent of visceral leishmaniasis (VL) in the Americas, Mediterranean basin and West and Central Asia. Although the geographic structure of L. infantum populations from the Old World have been described, few studies have addressed the population structure of this parasite in the Neotropical region. We employed 14 microsatellites to analyze the population structure of the L. infantum strains isolated from humans and dogs from most of the Brazilian states endemic for VL and from Paraguay. The results indicate a low genetic diversity, high inbreeding estimates and a depletion of heterozygotes, which together indicate a predominantly clonal breeding system, but signs of sexual events are also present. Three populations were identified from the clustering analysis, and they were well supported by F statistics inferences and partially corroborated by distance-based. POP1 (111 strains) was observed in all but one endemic area. POP2 (31 strains) is also well-dispersed, but it was the predominant population in Mato Grosso (MT). POP3 (31 strains) was less dispersed, and it was observed primarily in Mato Grosso do Sul (MS). Strains originated from an outbreak of canine VL in Southern Brazil were grouped in POP1 with those from Paraguay, which corroborates the hypothesis of dispersal from Northeastern Argentina and Paraguay. The distribution of VL in MS seems to follow the west-east construction of the Bolivia-Brazil pipeline from Corumbá municipality. This may have resulted in a strong association of POP3 and Lutzomyia cruzi, which is the main VL vector in Corumbá, and a dispersion of this population in this region that was shaped by human interference. This vector also occurs in MT and may influence the structure of POP2. This paper presents significant advances in the understanding of the population structure of L. infantum in Brazil and its association with eco-epidemiological aspects of VL. PMID:22606248
Ferreira, Gabriel Eduardo Melim; dos Santos, Barbara Neves; Dorval, Maria Elizabeth Cavalheiros; Ramos, Tereza Pompilio Bastos; Porrozzi, Renato; Peixoto, Alexandre Afranio; Cupolillo, Elisa
Leishmania infantum is the etiologic agent of visceral leishmaniasis (VL) in the Americas, Mediterranean basin and West and Central Asia. Although the geographic structure of L. infantum populations from the Old World have been described, few studies have addressed the population structure of this parasite in the Neotropical region. We employed 14 microsatellites to analyze the population structure of the L. infantum strains isolated from humans and dogs from most of the Brazilian states endemic for VL and from Paraguay. The results indicate a low genetic diversity, high inbreeding estimates and a depletion of heterozygotes, which together indicate a predominantly clonal breeding system, but signs of sexual events are also present. Three populations were identified from the clustering analysis, and they were well supported by F statistics inferences and partially corroborated by distance-based. POP1 (111 strains) was observed in all but one endemic area. POP2 (31 strains) is also well-dispersed, but it was the predominant population in Mato Grosso (MT). POP3 (31 strains) was less dispersed, and it was observed primarily in Mato Grosso do Sul (MS). Strains originated from an outbreak of canine VL in Southern Brazil were grouped in POP1 with those from Paraguay, which corroborates the hypothesis of dispersal from Northeastern Argentina and Paraguay. The distribution of VL in MS seems to follow the west-east construction of the Bolivia-Brazil pipeline from Corumbá municipality. This may have resulted in a strong association of POP3 and Lutzomyia cruzi, which is the main VL vector in Corumbá, and a dispersion of this population in this region that was shaped by human interference. This vector also occurs in MT and may influence the structure of POP2. This paper presents significant advances in the understanding of the population structure of L. infantum in Brazil and its association with eco-epidemiological aspects of VL.
Ferreira, Gabriel Eduardo Melim; dos Santos, Barbara Neves; Dorval, Maria Elizabeth Cavalheiros; Ramos, Tereza Pompilio Bastos; Porrozzi, Renato; Peixoto, Alexandre Afranio; Cupolillo, Elisa
BACKGROUND: Insecticide thermal fogging (ITF) is a tool to control vector borne diseases. Insecticide application success for vector control has been associated with housing materials and architecture. Vector abundance is correlated with weather changes. Nevertheless, housing quality and weather impacts on vector abundance have been unaccounted for in most New World insecticide control trials for leishmaniasis vectors. METHODS: We conducted a 15 month insecticide control trial that included two deltamethrin [6 mg a.i.m-2] based ITF interventions in 12 of 24 monitored houses at Trinidad de Las Minas, a hyperendemic cutaneous leishmaniasis transmission village in western Panama. During the study we followed sand fly (SF) abundance, keeping track of rainfall and quantified housing quality using an index based on architecture and construction materials. RESULTS: We found a 50 to 80% reduction in SF density in the fogged houses when compared with control houses, while controlling for seasonal changes in SF abundance associated with rainfall. We found heterogeneities in the reductions, as abundance changed according to SF species: Lutzomyia gomezi, Lu. panamensis, Lu. dysponeta and Lu. triramula reduced in density between 40% and 90% after ITF. In contrast, Lu. trapidoi density increased 5% after ITF. Differences in the impact of ITF were associated with housing quality, the most destitute houses, i.e., those with features that ease insect entrance, had a disproportionally larger SF abundance, in some cases with increased domiciliary SF density following the ITF. CONCLUSION: Our results suggest the potential of insecticide application to control SF density and leishmaniasis transmission could depend on housing quality beyond insecticide efficiency. PMID:23742709
Chaves, Luis Fernando; Calzada, Jose E; Rigg, Chystrie; Valderrama, Anayansi; Gottdenker, Nicole L; Saldaña, Azael
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 parental lines bearing independent drug markers, doubly-drug resistant hybrid progeny were selected, from which 96 clonal lines were analyzed for DNA content and genotyped for parent alleles at 4-6 unlinked nuclear loci as well as the maxicircle DNA. As seen previously, the majority of hybrids showed '2n' DNA contents, but with a significant number of '3n' and one '4n' offspring. In the natural vector, 97% of the nuclear loci showed both parental alleles; however, 3% (4/150) showed only one parental allele. In the unnatural vector, the frequency of uniparental inheritance rose to 10% (27/275). We attribute this to loss of heterozygosity after mating, most likely arising from aneuploidy which is both common and temporally variable in Leishmania. As seen previously, only uniparental inheritance of maxicircle kDNA was observed. Hybrids were recovered at similar efficiencies in all pairwise crosses tested, suggesting that L. major lacks detectable 'mating types' that limit free genetic exchange. In the natural vector, comparisons of the timing of hybrid formation with the presence of developmental stages suggest nectomonads as the most likely sexually competent stage, with hybrids emerging well before the first appearance of metacyclic promastigotes. These studies provide an important perspective on the prevalence of genetic exchange in natural populations of L. major and a guide for experimental studies to understand the biology of mating. PMID:23935521
Inbar, Ehud; Akopyants, Natalia S; Charmoy, Melanie; Romano, Audrey; Lawyer, Phillip; Elnaiem, Dia-Eldin A; Kauffmann, Florence; Barhoumi, Mourad; Grigg, Michael; Owens, Katherine; Fay, Michael; Dobson, Deborah E; Shaik, Jahangheer; Beverley, Stephen M; Sacks, David
The recent scientific literature on plant-derived agents with potential or effective use in the control of the arthropod vectors of human tropical diseases is reviewed. Arthropod-borne tropical diseases include: amebiasis, Chagas disease (American trypanosomiasis), cholera, cryptosporidiosis, dengue (hemorrhagic fever), epidemic typhus (Brill-Zinsser disease), filariasis (elephantiasis), giardia (giardiasis), human African trypanosomiasis (sleeping sickness), isosporiasis, leishmaniasis, Lyme disease (lyme borreliosis), malaria, onchocerciasis, plague, recurrent fever, sarcocystosis, scabies (mites as causal agents), spotted fever, toxoplasmosis, West Nile fever, and yellow fever. Thus, coverage was given to work describing plant-derived extracts, essential oils (EOs), and isolated chemicals with toxic or noxious effects on filth bugs (mechanical vectors), such as common houseflies (Musca domestica Linnaeus), American and German cockroaches (Periplaneta americana Linnaeus, Blatella germanica Linnaeus), and oriental latrine/blowflies (Chrysomya megacephala Fabricius) as well as biting, blood-sucking arthropods such as blackflies (Simulium Latreille spp.), fleas (Xenopsylla cheopis Rothschild), kissing bugs (Rhodnius Stål spp., Triatoma infestans Klug), body and head lice (Pediculus humanus humanus Linnaeus, P. humanus capitis De Geer), mosquitoes (Aedes Meigen, Anopheles Meigen, Culex L., and Ochlerotatus Lynch Arribálzaga spp.), sandflies (Lutzomyia longipalpis Lutz & Neiva, Phlebotomus Loew spp.), scabies mites (Sarcoptes scabiei De Geer, S. scabiei var hominis, S. scabiei var canis, S. scabiei var suis), and ticks (Ixodes Latreille, Amblyomma Koch, Dermacentor Koch, and Rhipicephalus Koch spp.). Examples of plant extracts, EOs, and isolated chemicals exhibiting noxious or toxic activity comparable or superior to the synthetic control agents of choice (pyrethroids, organophosphorous compounds, etc.) are provided in the text for many arthropod vectors of tropical diseases. PMID:21432748
Pohlit, Adrian Martin; Rezende, Alex Ribeiro; Lopes Baldin, Edson Luiz; Lopes, Norberto Peporine; Neto, Valter Ferreira de Andrade
Background Salivary hyaluronidases have been described in a few bloodsucking arthropods. However, very little is known about the presence of this enzyme in various bloodsucking insects and no data are available on its effect on transmitted microorganisms. Here, we studied hyaluronidase activity in thirteen bloodsucking insects belonging to four different orders. In addition, we assessed the effect of hyaluronidase coinoculation on the outcome of Leishmania major infection in BALB/c mice. Principal Findings High hyaluronidase activity was detected in several Diptera tested, namely deer fly Chrysops viduatus, blackflies Odagmia ornata and Eusimilium latipes, mosquito Culex quinquefasciatus, biting midge Culicoides kibunensis and sand fly Phlebotomus papatasi. Lower activity was detected in cat flea Ctenocephalides felis. No activity was found in kissing bug Rhodnius prolixus, mosquitoes Anopheles stephensi and Aedes aegypti, tse-tse fly Glossina fuscipes, stable fly Stomoxys calcitrans and human louse Pediculus humanus. Hyaluronidases of different insects vary substantially in their molecular weight, the structure of the molecule and the sensitivity to reducing conditions or sodium dodecyl sulphate. Hyaluronidase exacerbates skin lesions caused by Leishmania major; more severe lesions developed in mice where L. major promastigotes were coinjected with hyaluronidase. Conclusions High hyaluronidase activities seem to be essential for insects with pool-feeding mode, where they facilitate the enlargement of the feeding lesion and serve as a spreading factor for other pharmacologically active compounds present in saliva. As this enzyme is present in all Phlebotomus and Lutzomyia species studied to date, it seems to be one of the factors responsible for enhancing activity present in sand fly saliva. We propose that salivary hyaluronidase may facilitate the spread of other vector-borne microorganisms, especially those transmitted by insects with high hyaluronidase activity, namely blackflies (Simuliidae), biting midges (Ceratopogonidae) and horse flies (Tabanidae).
Volfova, Vera; Hostomska, Jitka; Cerny, Martin; Votypka, Jan; Volf, Petr
Background Immune responses to sandfly saliva have been shown to protect animals against Leishmania infection. Yet very little is known about the molecular characteristics of salivary proteins from different sandflies, particularly from vectors transmitting visceral leishmaniasis, the fatal form of the disease. Further knowledge of the repertoire of these salivary proteins will give us insights into the molecular evolution of these proteins and will help us select relevant antigens for the development of a vector based anti-Leishmania vaccine. Results Two salivary gland cDNA libraries from female sandflies Phlebotomus argentipes and P. perniciosus were constructed, sequenced and proteomic analysis of the salivary proteins was performed. The majority of the sequenced transcripts from the two cDNA libraries coded for secreted proteins. In this analysis we identified transcripts coding for protein families not previously described in sandflies. A comparative sandfly salivary transcriptome analysis was performed by using these two cDNA libraries and two other sandfly salivary gland cDNA libraries from P. ariasi and Lutzomyia longipalpis, also vectors of visceral leishmaniasis. Full-length secreted proteins from each sandfly library were compared using a stand-alone version of BLAST, creating formatted protein databases of each sandfly library. Related groups of proteins from each sandfly species were combined into defined families of proteins. With this comparison, we identified families of salivary proteins common among all of the sandflies studied, proteins to be genus specific and proteins that appear to be species specific. The common proteins included apyrase, yellow-related protein, antigen-5, PpSP15 and PpSP32-related protein, a 33-kDa protein, D7-related protein, a 39- and a 16.1- kDa protein and an endonuclease-like protein. Some of these families contained multiple members, including PPSP15-like, yellow proteins and D7-related proteins suggesting gene expansion in these proteins. Conclusion This comprehensive analysis allows us the identification of genus- specific proteins, species-specific proteins and, more importantly, proteins common among these different sandflies. These results give us insights into the repertoire of salivary proteins that are potential candidates for a vector-based vaccine.
Anderson, Jennifer M; Oliveira, Fabiano; Kamhawi, Shaden; Mans, Ben J; Reynoso, David; Seitz, Amy E; Lawyer, Phillip; Garfield, Mark; Pham, MyVan; Valenzuela, Jesus G
We report for the first time that saliva of the hard tick and Lyme disease vector, Ixodes scapularis, is a potent inhibitor of angiogenesis. Saliva (< or = 1:500 dilutions) or salivary gland (0.1-0.5 pairs/assay) dose-dependently inhibits microvascular endothelial cell (MVEC) proliferation. Inhibition was also detected with the saliva of the cattle tick Boophilus microplus but not with the salivary gland of Anopheles gambiae, An. stephensi, Lutzomyia longipalpis, Phlebotomus papatasi, Aedes aegypti, Culex quinquefasciatus, and Cimex lectularius. Inhibition of MVEC proliferation by I. Scapularis saliva was accompanied by a change in cell shape (shrinkage of the cytoplasm with loss of cell-cell interactions) and apoptosis which was estimated by expression of phosphatidylserine using the Apopercentage dye, and by a typical pattern of chromatin margination, condensation, and fragmentation as revealed by nuclear staining with Hoechst 33258. The effect of saliva appears to be mediated by endothelial cell alpha5beta1 integrin, because monoclonal antibodies against this but not alphavbeta3, alphavbeta5, alpha9beta1, or alpha2beta1 integrins remarkably block its effect. In addition, SDS/PAGE shows that saliva specifically degrades purified alpha5beta1 but not alphavbeta5 or alphavbeta3 integrins. Incubation of saliva with EDTA and 1,10-phenanthroline, but not phenylmethylsulfonyl fluoride (PMSF), inhibits saliva-dependent degradation of purified alpha5beta1 integrin, suggesting that a metalloprotease is responsible for the activity. Finally, saliva at < or = 1:1,000 dilutions blocks sprouting formation from chick embryo aorta implanted in Matrigel, an in vitro model of angiogenesis. These findings introduce the concept that tick saliva is a negative modulator of angiogenesis-dependent wound healing and tissue repair, therefore allowing ticks to feed for days. Inhibition of angiogenesis was hitherto an unidentified biologic property of the saliva of any blood-sucking arthropod studied so far. Its presence in tick saliva may be regarded as an additional source of angiogenesis inhibitors with potential applications for the study of both vector and vascular biology. PMID:16113800
Francischetti, Ivo M B; Mather, Thomas N; Ribeiro, José M C
Bloodsucking arthropods are a rich source of salivary molecules (sialogenins) which inhibit platelet aggregation, neutrophil function and angiogenesis. Here we review the literature on salivary disintegrins and their targets. Disintegrins were first discovered in snake venoms, and were instrumental in our understanding of integrin function and also for the development of anti-thrombotic drugs. In hematophagous animals, most disintegrins described so far have been discovered in the salivary gland of ticks and leeches. A limited number have also been found in hookworms and horseflies, and none identified in mosquitoes or sand flies. The vast majority of salivary disintegrins reported display a RGD motif and were described as platelet aggregation inhibitors, and few others as negative modulator of neutrophil or endothelial cell functions. This notably low number of reported disintegrins is certainly an underestimation of the actual complexity of this family of proteins in hematophagous secretions. Therefore an algorithm was created in order to identify the tripeptide motifs RGD, KGD, VGD, MLD, KTS, RTS, WGD, or RED (flanked by cysteines) in sialogenins deposited in GenBank database. The search included sequences from various blood-sucking animals such as ticks (e.g., Ixodes sp., Argas sp., Rhipicephalus sp., Amblyommasp.), tabanids (e.g., Tabanus sp.), bugs (e.g., Triatoma sp., Rhodnius prolixus), mosquitoes (e.g., Anopheles sp., Aedes sp., Culex sp.), sand flies (e.g., Lutzomyia sp., Phlebotomus sp.), leeches (e.g., Macrobdella sp., Placobdella sp.) and worms (e.g., Ancylostoma sp.). This approach allowed the identification of a remarkably high number of novel putative sialogenins with tripeptide motifs typical of disintegrins (>450 sequences) whose biological activity remains to be verified. This database is accessible online as a hyperlinked worksheet and displays biochemical, taxonomic, and gene ontology aspects for each putative disintegrin. It is also freely available for download (right click with the mouse) at links http://exon.niaid.nih.gov/transcriptome/RGD/RGD-Peps-WEB.xlsx (web version) and http://exon.niaid.nih.gov/transcriptome/RGD/RGD-sialogenins.zip (stand alone version). PMID:22778902
Assumpcao, Teresa C F; Ribeiro, José M C; Francischetti, Ivo M B