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p. 1-16 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-11-24T12:47:30Z No. of bitstreams: 1 Tatiana R. de Moura.pdf: 2866121 bytes, checksum: aef5ca382007e522140bb8e55395da18 (MD5) Approved for entry into archive by Delba Rosa (delba@ufba.br) on 2015-05-11T14:57:14Z (GMT) No. of bitstreams: 1 Tatiana R. de Moura.pdf: 2866121 bytes, checksum: aef5ca382007e522140bb8e55395da18 (MD5) Made available in DSpace on 2015-05-11T14:57:14Z (GMT). No. of bitstreams: 1 Tatiana R. de Moura.pdf: 2866121 bytes, checksum: aef5ca382007e522140bb8e55395da18 (MD5) Previous issue date: 2013 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-γ-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.

Texto completo: acesso restrito. p. 985–995 Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2014-04-29T14:11:17Z No. of bitstreams: 1 1-s2.0-S1549963413001755-main.pdf: 1378587 bytes, checksum: 7f7ed57efe858a0fe0a69d986cc9e5a5 (MD5) Approved for entry into archive by Rodrigo Meirelles (rodrigomei@ufba.br) on 2014-09-09T14:49:36Z (GMT) No. of bitstreams: 1 1-s2.0-S1549963413001755-main.pdf: 1378587 bytes, checksum: 7f7ed57efe858a0fe0a69d986cc9e5a5 (MD5) Made available in DSpace on 2014-09-09T14:49:36Z (GMT). No. of bitstreams: 1 1-s2.0-S1549963413001755-main.pdf: 1378587 bytes, checksum: 7f7ed57efe858a0fe0a69d986cc9e5a5 (MD5) Previous issue date: 2013 We recently demonstrated that immunization with polyester poly(lactide-co-glycolide acid) (PLGA) nanoparticles loaded with the 11-kDa Leishmania vaccine candidate kinetoplastid membrane protein 11 (KMP-11) significantly reduced parasite load in vivo. Presently, we explored the ability of the recombinant PLGA nanoparticles to stimulate innate responses in macrophages and the outcome of infection with Leishmania braziliensis in vitro. Incubation of macrophages with KMP-11-loaded PLGA nanoparticles significantly decreased parasite load. In parallel, we observed the augmented production of nitric oxide, superoxide, TNF-α and IL-6. An increased release of CCL2/MCP-1 and CXCL1/KC was also observed, resulting in macrophage and neutrophil recruitment in vitro. Lastly, the incubation of macrophages with KMP-11-loaded PLGA nanoparticles triggered the activation of caspase-1 and the secretion of IL-1β and IL-18, suggesting inflammasome participation. Inhibition of caspase-1 significantly increased the parasite load. We conclude that KMP-11-loaded PLGA nanoparticles promote the killing of intracellular Leishmania parasites through the induction of potent innate responses.

p. 1-16 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-11-24T12:47:30Z No. of bitstreams: 1 Tatiana R. de Moura.pdf: 2866121 bytes, checksum: aef5ca382007e522140bb8e55395da18 (MD5) Approved for entry into archive by Delba Rosa (delba@ufba.br) on 2015-05-11T14:57:14Z (GMT) No. of bitstreams: 1 Tatiana R. de Moura.pdf: 2866121 bytes, checksum: aef5ca382007e522140bb8e55395da18 (MD5) Made available in DSpace on 2015-05-11T14:57:14Z (GMT). No. of bitstreams: 1 Tatiana R. de Moura.pdf: 2866121 bytes, checksum: aef5ca382007e522140bb8e55395da18 (MD5) Previous issue date: 2013 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-γ-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.

Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-08-28T15:12:55Z No. of bitstreams: 1 journal.pntd.0000712-1.pdf: 2303990 bytes, checksum: d1b2cada44c96cb500082a7a33d1bc46 (MD5) Approved for entry into archive by Rodrigo Meirelles (rodrigomei@ufba.br) on 2013-10-31T18:07:57Z (GMT) No. of bitstreams: 1 journal.pntd.0000712-1.pdf: 2303990 bytes, checksum: d1b2cada44c96cb500082a7a33d1bc46 (MD5) Made available in DSpace on 2013-10-31T18:07:57Z (GMT). No. of bitstreams: 1 journal.pntd.0000712-1.pdf: 2303990 bytes, checksum: d1b2cada44c96cb500082a7a33d1bc46 (MD5) Previous issue date: 2010 Background: During blood feeding, sand flies inject Leishmania parasites in the presence of saliva. The types and functions of cells present at the first host-parasite contact are critical to the outcome on infection and sand fly saliva has been shown to play an important role in this setting. Herein, we investigated the in vivo chemotactic effects of Lutzomyia intermedia saliva, the vector of Leishmania braziliensis, combined or not with the parasite. Methods and Findings: We tested the initial response induced by Lutzomyia intermedia salivary gland sonicate (SGS) in BALB/c mice employing the air pouch model of inflammation. L. intermedia SGS induced a rapid influx of macrophages and neutrophils. In mice that were pre-sensitized with L. intermedia saliva, injection of SGS was associated with increased neutrophil recruitment and a significant up-regulation of CXCL1, CCL2, CCL4 and TNF-α expression. Surprisingly, in mice that were pre-exposed to SGS, a combination of SGS and L. braziliensis induced a significant migration of neutrophils and an important modulation in cytokine and chemokine expression as shown by decreased CXCL10 expression and increased IL-10 expression. Conclusion: These results confirm that sand fly saliva modulates the initial host response. More importantly, pre-exposure to L. intermedia saliva significantly modifies the host's response to L. braziliensis, in terms of cellular recruitment and expression of cytokines and chemokines. This particular immune modulation may, in turn, favor parasite multiplication.

Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-08-28T15:12:55Z No. of bitstreams: 1 journal.pntd.0000712-1.pdf: 2303990 bytes, checksum: d1b2cada44c96cb500082a7a33d1bc46 (MD5) Approved for entry into archive by Rodrigo Meirelles (rodrigomei@ufba.br) on 2013-10-31T18:07:57Z (GMT) No. of bitstreams: 1 journal.pntd.0000712-1.pdf: 2303990 bytes, checksum: d1b2cada44c96cb500082a7a33d1bc46 (MD5) Made available in DSpace on 2013-10-31T18:07:57Z (GMT). No. of bitstreams: 1 journal.pntd.0000712-1.pdf: 2303990 bytes, checksum: d1b2cada44c96cb500082a7a33d1bc46 (MD5) Previous issue date: 2010 Background: During blood feeding, sand flies inject Leishmania parasites in the presence of saliva. The types and functions of cells present at the first host-parasite contact are critical to the outcome on infection and sand fly saliva has been shown to play an important role in this setting. Herein, we investigated the in vivo chemotactic effects of Lutzomyia intermedia saliva, the vector of Leishmania braziliensis, combined or not with the parasite. Methods and Findings: We tested the initial response induced by Lutzomyia intermedia salivary gland sonicate (SGS) in BALB/c mice employing the air pouch model of inflammation. L. intermedia SGS induced a rapid influx of macrophages and neutrophils. In mice that were pre-sensitized with L. intermedia saliva, injection of SGS was associated with increased neutrophil recruitment and a significant up-regulation of CXCL1, CCL2, CCL4 and TNF-α expression. Surprisingly, in mice that were pre-exposed to SGS, a combination of SGS and L. braziliensis induced a significant migration of neutrophils and an important modulation in cytokine and chemokine expression as shown by decreased CXCL10 expression and increased IL-10 expression. Conclusion: These results confirm that sand fly saliva modulates the initial host response. More importantly, pre-exposure to L. intermedia saliva significantly modifies the host's response to L. braziliensis, in terms of cellular recruitment and expression of cytokines and chemokines. This particular immune modulation may, in turn, favor parasite multiplication.