Salivary gland lysates from the sand fly Lutzomyia longipalpis enhance Leishmania infectivity

ABSTRACT In this report, we describe an investigation of the effects of Lutzomyia longipalpis sand fly salivary gland homogenates (SGH) on cytokine production and expression of costimulatory molecules on human monocytes, macrophages (Mφs), and dendritic cells (DCs). SGH of L. longipalpis induced an increase in interleukin-6 (IL-6), IL-8 and IL-12p40 production but a decrease in tumor necrosis factor alpha and IL-10 production by lipopolysaccharida (LPS)-stimulated monocytes. We also examined the expression of costimulatory molecules on the surface of monocytes, Mφs, and DCs. Whereas SGH affected the expression of these molecules on monocytes and Mφs, it had little effect on these molecules on DCs. However, when DCs were generated from human monocytes in the presence of SGH, SGH inhibited the expression of costimulatory molecules. In addition, a decrease in the maturation of DCs induced by CD40L was observed in the presence of SGH. Finally, preincubating SGH with human sera containing anti-SGH-specific antibodies abolished the effects of SGH on cytokine production by LPS-stimulated monocytes.

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The salivary apyrase of the blood-sucking sand fly Phlebotomus papatasi belongs to the novel Cimex family of apyrases

Journal of Experimental Biology ◽

10.1242/jeb.204.2.229 ◽

2001 ◽

Vol 204 (2) ◽

pp. 229-237 ◽

Cited By ~ 1

Author(s):

J.G. Valenzuela ◽

Y. Belkaid ◽

E. Rowton ◽

J.M. Ribeiro

Keyword(s):

Salivary Gland ◽

Fruit Fly ◽

Sand Fly ◽

Lutzomyia Longipalpis ◽

The Novel ◽

Phlebotomus Papatasi ◽

Blood Sucking ◽

Enzyme Sequence ◽

Enzyme Functions ◽

Sugar Kinase

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.

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An Integrated Approach Using Spatial Analysis to Study the Risk Factors for Leishmaniasis in Area of Recent Transmission

BioMed Research International ◽

10.1155/2015/621854 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Júlia Alves Menezes ◽

Eduardo de Castro Ferreira ◽

José Dilermando Andrade-Filho ◽

Alessandra Mara de Sousa ◽

Mayron Henrique Gomes Morais ◽

...

Keyword(s):

Spatial Analysis ◽

Integrated Approach ◽

Climatic Conditions ◽

Sand Fly ◽

Leishmania Braziliensis ◽

Lutzomyia Longipalpis ◽

Recent Transmission ◽

Current Transmission ◽

Canine Infection ◽

The City

Some epidemiological aspects of leishmaniasis in the municipality of Formiga, Brazil, an important touristic site, were evaluated. Those included phlebotomine sand fly vectors, canine infection, and geoprocessing analysis for determining critical transmission areas. Sand flies (224 insects) belonging to ten different species were captured. The most captured species includedLutzomyia longipalpis(35.3%),Lutzomyia cortelezzii(33.5%), andLutzomyia whitmani(18.3%). A significant correlation between sand fly densities and climatic conditions was detected. Serological diagnosis (DPP and ELISA) was performed in 570 dogs indicating a prevalence of 5.8%. After sequencing the main species circulating in the area wereLeishmania infantumandLeishmania braziliensis. Spatial analysis demonstrated that vegetation and hydrography may be related to sand fly distribution and infected dogs. The municipality of Formiga has proven leishmaniasis vectors and infected dogs indicating the circulation of the parasite in the city. Correlation of those data with environmental and human cases has identified the critical areas for control interventions (south, northeast, and northwest). In conclusion, there is current transmission of visceral and canine human cases and the city is on the risk for the appearance of cutaneous cases.

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DISTINCT CELLULAR MIGRATION INDUCED BY Leishmania infantum chagasi AND SALIVA FROM Lutzomyia longipalpis IN A HEMORRHAGIC POOL MODEL

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652014000100003 ◽

2014 ◽

Vol 56 (1) ◽

pp. 21-27 ◽

Cited By ~ 4

Author(s):

Camila Oliveira Vasconcelos ◽

Zirlane C. Branco Coelho ◽

Cristina de Souza Chaves ◽

Clarissa Romero Teixeira ◽

Margarida M. Lima Pompeu ◽

...

Keyword(s):

Cell Population ◽

Cellular Migration ◽

Sand Fly ◽

Leishmania Infection ◽

Lutzomyia Longipalpis ◽

Specific Cell ◽

Air Pouch ◽

Leukocyte Accumulation ◽

Pool Model ◽

Sand Fly Vectors

Recruitment of a specific cell population after Leishmania infection can influence the outcome of the disease. Cellular migration in response to Leishmania or vector saliva has been reported in air pouch model, however, cellular migration induced by Leishmania associated with host's blood and vector saliva in this model has not been described. Herein we investigated cellular migration into air pouch of hamster after stimulation with combination of L. chagasi and host's blood and Lutzomyia longipalpis saliva. Migration induced by saliva was 3-fold more than those induced by L. chagasi alone. Additionally, L. chagasi associated with blood and saliva induced significantly even more leukocytes into air pouch than Leishmania alone. L. chagasi recruited a diverse cell population; however, most of these cells seem to have not migrated to the inflammatory exudate, remaining in the pouch lining tissue. These results indicate that L. chagasi can reduce leukocyte accumulation to the initial site of infection, and when associated with vector saliva in the presence of blood components, increase the influx of more neutrophils than macrophages, suggesting that the parasite has developed a strategy to minimize the initial inflammatory response, allowing an unlimited progression within the host. This work reinforces the importance of studies on the salivary components of sand fly vectors of leishmaniasis in the transmission process and the establishment of the infection.

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Odour of domestic dogs infected with Leishmania infantum is attractive to female but not male sand flies: Evidence for parasite manipulation

PLoS Pathogens ◽

10.1371/journal.ppat.1009354 ◽

2021 ◽

Vol 17 (3) ◽

pp. e1009354

Author(s):

Monica E. Staniek ◽

James G. C. Hamilton

Keyword(s):

Leishmania Infantum ◽

Etiologic Agent ◽

Human Infection ◽

T Test ◽

Sand Fly ◽

Lutzomyia Longipalpis ◽

Sand Flies ◽

Control Female ◽

Behavioural Experiments ◽

Paired T Test

Globally visceral leishmaniasis (VL) causes thousands of human deaths every year. In South America, the etiologic agent, Leishmania infantum, is transmitted from an infected canine reservoir to human hosts by the bite of the sand fly vector; predominantly Lutzomyia longipalpis. Previous evidence from model rodent systems have suggested that the odour of infected hosts is altered by the parasite making them more attractive to the vector leading to an increased biting rate and improved transmission prospects for the pathogen. However, there has been no assessment of the effect of Le infantum infection on the attractiveness of dogs, which are the natural reservoirs for human infection. Hair collected from infected and uninfected dogs residing in a VL endemic city in Brazil was entrained to collect the volatile chemical odours present in the headspace. Female and male Lu. longipalpis sand flies were offered a choice of odour entrained from infected and uninfected dogs in a series of behavioural experiments. Odour of uninfected dogs was equally attractive to male or female Lu. longipalpis when compared to a solvent control. Female Lu. longipalpis were significantly more attracted to infected dog odour than uninfected dog odour in all 15 experimental replicates (average 45.7±0.87 females attracted to infected odour; 23.9±0.82 to uninfected odour; paired T-test, P = 0.000). Male Lu. longipalpis did not significantly prefer either infected or uninfected odour (average 36.1±0.4 males to infected odour; 35.7±0.6 to uninfected odour; paired T-test, P = 0.722). A significantly greater proportion of females chose the infected dog odour compared to the males (paired T-test, P = 0.000). The results showed that the odour of dogs infected with Le. infantum was significantly more attractive to blood-seeking female sand flies than it was to male sand flies. This is strong evidence for parasite manipulation of the host odour in a natural transmission system and indicates that infected dogs may have a disproportionate significance in maintaining infection in the canine and human population.

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