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1.
Parasit Vectors. 2014 May 30;7(1):252. doi: 10.1186/1756-3305-7-252.

Infection with dengue-2 virus alters proteins in naturally expectorated saliva of Aedes aegypti mosquitoes.

Author information

  • 1Department of Pathobiological Sciences, Vector-borne Disease Laboratories, Louisiana State University, School of Veterinary Medicine, Baton Rouge, LA, USA. cmores@lsu.edu.

Abstract

BACKGROUND:

Dengue virus (DENV) is responsible for up to approximately 300 million infections and an increasing number of deaths related to severe manifestations each year in affected countries throughout the tropics. It is critical to understand the drivers of this emergence, including the role of vector-virus interactions. When a DENV-infected Aedes aegypti mosquito bites a vertebrate, the virus is deposited along with a complex mixture of salivary proteins. However, the influence of a DENV infection upon the expectorated salivary proteome of its vector has yet to be determined.

METHODS:

Therefore, we conducted a proteomic analysis using 2-D gel electrophoresis coupled with mass spectrometry based protein identification comparing the naturally expectorated saliva of Aedes aegypti infected with DENV-2 relative to that of uninfected Aedes aegypti.

RESULTS:

Several proteins were found to be differentially expressed in the saliva of DENV-2 infected mosquitoes, in particular proteins with anti-hemostatic and pain inhibitory functions were significantly reduced. Hypothetical consequences of these particular protein reductions include increased biting rates and transmission success, and lead to alteration of transmission potential as calculated in our vectorial capacity model.

CONCLUSIONS:

We present our characterizations of these changes with regards to viral transmission and mosquito blood-feeding success. Further, we conclude that our proteomic analysis of Aedes aegypti saliva altered by DENV infection provides a unique opportunity to identify pro-viral impacts key to virus transmission.

PMID:
24886023
[PubMed - in process]
PMCID:
PMC4057903
Free PMC Article
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2.
Am J Trop Med Hyg. 2014 Mar;90(3):431-7. doi: 10.4269/ajtmh.13-0412. Epub 2014 Jan 20.

Effect of dengue-2 virus infection on protein expression in the salivary glands of Aedes aegypti mosquitoes.

Author information

  • 1School of Veterinary Medicine, Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana; Faculty of Health, Department of Microbiology, University of Pamplona, Pamplona, Norte de Santander, Colombia.

Abstract

Dengue virus (DENV) is the most important mosquito-transmitted flavivirus that is transmitted throughout the tropical and subtropical regions of the world. The primary mosquito vector of DENV in urban locations is Aedes aegypti. Key to understanding the transmission of DENV is the relationship between pathogen and vector. Accordingly, we report our preliminary characterization of the differentially expressed proteins from Ae. aegypti mosquitoes after DENV infection. We investigated the virus-vector interaction through changes in the proteome of the salivary glands of mosquitoes with disseminated DENV serotype 2 (DENV-2) infections using two-dimensional gel electrophoresis and identification by mass spectrometry. Our findings indicate that DENV-2 infection in the Ae. aegypti salivary gland alters the expression of structural, secreted, and metabolic proteins. These changes in the salivary gland proteome highlight the virally influenced environment caused by a DENV-2 infection and warrant additional investigation to determine if these differences extend to the expectorated saliva.

PMID:
24445208
[PubMed - indexed for MEDLINE]
PMCID:
PMC3945687
[Available on 2015/3/5]
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3.
PLoS One. 2013 Dec 2;8(12):e81211. doi: 10.1371/journal.pone.0081211. eCollection 2013.

Use of anti-Aedes aegypti salivary extract antibody concentration to correlate risk of vector exposure and dengue transmission risk in Colombia.

Author information

  • 1Louisiana State University, Baton Rouge, Louisiana, United States of America ; Universidad de Pamplona, Pamplona, Colombia.

Abstract

Norte de Santander is a region in Colombia with a high incidence of dengue virus (DENV). In this study, we examined the serum concentration of anti-Aedes salivary gland extract (SGE) antibodies as a biomarker of DENV infection and transmission, and assessed the duration of anti-SGE antibody concentration after exposure to the vector ceased. We also determined whether SGE antibody concentration could differentiate between positive and negative DENV infected individuals and whether there are differences in exposure for each DENV serotype. We observed a significant decrease in the concentration of IgG antibodies at least 40 days after returning to an "Ae. aegypti-free" area. In addition, we found significantly higher anti-SGE IgG concentrations in DENV positive patients with some difference in exposure to mosquito bites among DENV serotypes. We conclude that the concentration of IgG antibodies against SGE is an accurate indicator of risk of dengue virus transmission and disease presence.

PMID:
24312537
[PubMed - indexed for MEDLINE]
PMCID:
PMC3846924
Free PMC Article
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4.
Acta Trop. 2012 Jan;121(1):6-12. doi: 10.1016/j.actatropica.2011.09.005. Epub 2011 Sep 29.

Genetic diversity in the merozoite surface protein 1 and 2 genes of Plasmodium falciparum from the Artibonite Valley of Haiti.

Author information

  • 1Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA 70112, USA. berlinlondo@yahoo.com

Abstract

Describing genetic diversity of the Plasmodium falciparum parasite provides important information about the local epidemiology of malaria. In this study, we examined the genetic diversity of P. falciparum isolates from the Artibonite Valley in Haiti using the allelic families of merozoite surface protein 1 and 2 genes (msp-1 and msp-2). The majority of study subjects infected with P. falciparum had a single parasite genotype (56% for msp-1 and 69% for msp-2: n=79); 9 distinct msp-1 genotypes were identified by size differences on agarose gels. K1 was the most polymorphic allelic family with 5 genotypes (amplicons from 100 to 300 base pairs [bp]); RO33 was the least polymorphic, with a single genotype (120-bp). Although both msp-2 alleles (3D7/IC1, FC27) had similar number of genotypes (n=4), 3D7/IC1 was more frequent (85% vs. 26%). All samples were screened for the presence of the K76T mutation on the P. falciparum chloroquine resistance transporter (pfcrt) gene with 10 of 79 samples positive. Of the 2 (out of 10) samples from individuals follow-up for 21 days, P. falciparum parasites were present through day 7 after treatment with chloroquine. No parasites were found on day 21. Our results suggest that the level of genetic diversity is low in this area of Haiti, which is consistent with an area of low transmission.

Copyright © 2011 Elsevier B.V. All rights reserved.

PMID:
21982798
[PubMed - indexed for MEDLINE]
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5.
J Med Entomol. 2010 Nov;47(6):1156-63.

Antibody response against Anopheles albimanus (Diptera: Culicidae) salivary protein as a measure of mosquito bite exposure in Haiti.

Author information

  • 1Department of Tropical Medicine, SPHTM, Tulane University, New Orleans, LA 70112, USA. blondono@tulane.edu

Abstract

Antibodies against arthropod saliva have shown to be a good marker of bite exposure. Because Anopheles albimanus Wiedemann (Diptera: Culicidae) is the principal malaria vector in Haiti, we evaluated the immune response against salivary gland extract (SGE) of this species in malaria-positive and malaria-negative subjects from this country. The results showed that the level of anti-SGE immunoglobulin (Ig)G antibodies was higher in patients with clinical malaria than those in malaria uninfected people living in the same region. In addition, a significant positive correlation between the level of anti-An. albimanus IgG and IgM antibody levels was observed. These results suggest that antibodies against An. albimanus saliva, especially IgG, are useful markers of mosquito bite exposure in Haiti.

PMID:
21175067
[PubMed - indexed for MEDLINE]
6.
Emerg Infect Dis. 2009 May;15(5):735-40. doi: 10.3201/eid1505.081063.

Chloroquine-resistant haplotype Plasmodium falciparum parasites, Haiti.

Author information

  • 1Tulane University, New Orleans, Louisiana, USA.

Abstract

Plasmodium falciparum parasites have been endemic to Haiti for >40 years without evidence of chloroquine (CQ) resistance. In 2006 and 2007, we obtained blood smears for rapid diagnostic tests (RDTs) and filter paper blots of blood from 821 persons by passive and active case detection. P. falciparum infections diagnosed for 79 persons by blood smear or RDT were confirmed by PCR for the small subunit rRNA gene of P. falciparum. Amplification of the P. falciparum CQ resistance transporter (pfcrt) gene yielded 10 samples with amplicons resistant to cleavage by ApoI. A total of 5 of 9 samples had threonine at position 76 of pfcrt, which is consistent with CQ resistance (haplotypes at positions 72-76 were CVIET [n = 4] and CVMNT [n = 1]); 4 had only the wild-type haplotype associated with CQ susceptibility (CVMNK). These results indicate that CQ-resistant haplotype P. falciparum malaria parasites are present in Haiti.

PMID:
19402959
[PubMed - indexed for MEDLINE]
PMCID:
PMC2686998
Free PMC Article
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7.
Emerg Infect Dis. 2007 Oct;13(10):1494-6. doi: 10.3201/eid1310.070567.

Prevalence of Plasmodium falciparum infection in rainy season, Artibonite Valley, Haiti, 2006.

Author information

  • 1Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana 70112, USA. teisele@tulane.edu

Abstract

We conducted a population-based survey to estimate the prevalence of Plasmodium falciparum infection among persons older than 1 month in the Artibonite Valley of Haiti during the high malaria transmission season in 2006. Results from PCR for 714 persons showed a prevalence of 3.1% for P. falciparum infection.

PMID:
18257993
[PubMed - indexed for MEDLINE]
PMCID:
PMC2851522
Free PMC Article
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8.
Phytother Res. 2006 Jun;20(6):444-7.

Prevention of sporogony of Plasmodium vivax in Anopheles albimanus by steroids of Solanum nudum Dunal (Solanaceae).

Author information

  • 1Grupo Malaria, Universidad de Antioquia, Medellín, Colombia.

Abstract

The sporontocidal activity of three steroids (SN-1, SN-2 and SN-4) from Solanum nudum Dunal (Solanaceae) was determined against naturally circulating isolates of Plasmodium vivax in Anopheles albimanus. Laboratory-reared Anopheles albimanus mosquitoes were infected with P. vivax from gametocytemic blood of volunteers resident in Buenaventura, Valle del Cauca (Colombian Pacific Coast) by using an artificial membrane feeder. Prior to mosquito feeding, gametocytemic blood was centrifuged, plasma was separated, packed blood red cells were washed with RPMI 1640 and then resuspended in non-immune AB serum, then the steroids were added at different doses. On day 7 after infection, the presence and number of oocysts in mosquitoes was determined. The steroid SN-2 reduced the infection of mosquitoes by 90% and the mean number of oocysts by 60%. These data confirmed that the experimental steroid is capable of interrupting the sporogonic development of P. vivax in Anopheles albimanus. This experimental steroid has potential for transmission blocking in vivax malaria.

PMID:
16619357
[PubMed - indexed for MEDLINE]
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9.
Phytother Res. 2006 Apr;20(4):267-73.

Effect of Solanum nudum Dunal (Solanaceae) steroids on hepatic trophozoites of Plasmodium vivax.

Author information

  • 1Grupo Malaria, Universidad de Antioquia, Medellín, Colombia.

Erratum in

  • Phytother Res. 2006 Jun;20(6):518.

Abstract

Steroids isolated from the plant Solanum nudum showed antiplasmodial activity against the blood stages of Plasmodium falciparum. It has been demonstrated that these steroids are neither mutagenic in vitro nor clastogenic in vivo. This study evaluated the effect of five steroids of S. nudum (SN-1, SN-2, SN-3, SN-4 and SN-5) on hepatic trophozoites of P. vivax, using an experimental design, non-balanced, with blind determination of the effect expressed as the percentage reduction of hepatic trophozoites. The sporozoites used to inoculate human hepatoma cells HepG2-A16 were obtained from gametocytemic blood of volunteers infected only with P. vivax, and passed into laboratory-reared Anopheles albimanus mosquitoes. Steroids were added at three different doses (100, 10 and 1 microg/mL) just after inoculation of the cells with sporozoites. The effect was determined by indirect immunofluorescence assays using the monoclonal antibodies Pv210 or Pv47E-2E10 and steroid cytotoxicity on HepG2-A16 cells was assessed by the MTT method. All the steroids reduced the number of hepatic P. vivax trophozoites, SN-2 and SN-4 reduced the number of hepatic trophozoites by 47% and 39% (p < 0.05), respectively.

Copyright 2006 John Wiley & Sons, Ltd.

PMID:
16557608
[PubMed - indexed for MEDLINE]
Icon for John Wiley & Sons, Inc.
10.
Biomedica. 2002 Dec;22(4):466-75.

[Comparison between OptiMAL and the thick smear tests for malaria diagnosis in an endemic area during a non-epidemic period].

[Article in Spanish]

Author information

  • 1Grupo Malaria, Facultad de Medicina, Universidad de Antioquia.

Abstract

The capacity of Optimal to diagnose malaria was compared with the thick smear test in two representative samples, one with acute febrile syndrome (AFS) n = 107, and another diagnosed by thick smear test (AFS + M) n = 82. The samples were chosen from patients at the malaria diagnostic clinic in Turbo, Antioquia, Colombia, between June and August 2000. The study was designed to be descriptive, prospective, and cross-sectional. The two tests were applied simultaneously in the AFS group (parallel, double blind design), and in sequential form in the AFS + M group. The thick smear test was the standard test. Optimal tests were carried out according to the manufacturer's instructions. In the parallel design, Optimal showed, for Plasmodium falciparum, a sensitivity of 40% [95% CI: 18-67], a specificity of 98% (95% CI: 92-100) and positive and negative predictive values of 75% (95% CI: 36-96) and 91% (95% CI: 83-96%), respectively. For Plasmodium vivax, it showed a sensitivity of 97% (95% CI: 82-100), a specificity of 89% (95% CI: 80-95) and positive and negative predictive values of 79% (95% CI: 62-90) and 98% (95% CI: 91-100). With the sequential design, Optimal showed a sensitivity of 67% (95% CI: 52-79) and 97% (95% CI: 83-100) for P. falciparum and P. vivax, respectively. For P. falciparum, the sensitivity was directly proportional to the parasitemia, while the sensitivity for P. vivax was independent from the parasitemia. The diagnostic values and operative characteristics of the thick smear test surpassed the Optimal test in its sensitivity for P. falciparum; the specificities were similar. Both tests were nearly identical in their diagnostic capacity for P. vivax. These results recommend that the thick smear test be retained as a routine or reference test for malaria diagnosis, with Optimal used as an ancillary test.

PMID:
12596444
[PubMed - indexed for MEDLINE]

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