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1.
Chemosphere ; 250: 126248, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32092573

ABSTRACT

Medium density fiberboard (MDF) wastes were converted into an efficient char able to uptake Food Red 17 dye (FR17) from colored effluents. The yield of the pyrolysis process, in terms of char, was 29%. The produced char presented micro and mesoporous, with surface area of 218.8 m2 g-1 and total pore volume of 0.122 cm3 g-1. Regarding to the FR17 adsorption, removal percentages of 90% were found at pH 2 and using 0.5 g L-1 of char. Pseudo-first and pseudo-second order models were adequate to represent the adsorption kinetic profile, being the equilibrium reached within 20 min. Freundlich model was selected to represent the equilibrium data. The maximum adsorption capacity was 210 mg g-1. The adsorption of FR17 on the char was endothermic and physical in nature. The char was efficient for 8 adsorption-desorption cycles, maintaining the same adsorption capacity. In brief, this work demonstrated a useful practice in terms of cleaner production. It was possible add value to MDF wastes, generating an efficient and reusable adsorbent to treat colored effluents containing FR 17 dye.


Subject(s)
Azo Compounds/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Adsorption , Coloring Agents , Hydrogen-Ion Concentration , Kinetics , Pyrolysis , Water , Water Pollutants, Chemical/analysis
2.
Environ Geochem Health ; 42(9): 2771-2788, 2020 Sep.
Article in English | MEDLINE | ID: mdl-31900823

ABSTRACT

The chemical reactions of dry-disposed ash dump, ingressed oxygen, carbon dioxide, and infiltrating rainwater affect mineralogical transformation, redistribution, and migration of chemical species. Composite samples of weathered coal fly ash taken at various depths and fresh coal fly ash were examined using organic petrographic, X-ray diffraction, X-ray fluorescence techniques, and successive extraction procedures. Results obtained show relative enrichment of glass, Al-Fe-oxides, calcite, and tridymite in the weathered CFA, but the fresh CFA is enriched in mullite, inertinite, maghemite, and ettringite. The enrichment of the weathered CFA in amorphous glass suggests higher reactivity when compared to fresh CFA. The evident depletion of soluble oxides in the weathered CFA is attributed to flushing of the soluble salts by percolating rainwater. Comparative enrichment of examined elements in water-soluble, exchangeable, reducible, and residual fractions of the weathered CFA is partly due to the slow release of adsorbed chemical species from the alumina-silicate matrix and diffusion from the deeper sections of the particles of coal fly ash. Sodium and potassium show enrichment in the oxidisable fraction of fresh CFA. The estimated mobility factor indicates mobility for Ca, Mg, Na, Se, Mo, and Sb and K, Sr, V, Cu, Cr, Se, and B in fresh and weathered CFAs, respectively.


Subject(s)
Coal Ash/chemistry , Metals/analysis , Waste Management/methods , Carbon Dioxide/chemistry , Chemical Fractionation , Coal Ash/analysis , Metals/chemistry , Soil/chemistry , Solubility , South Africa , Spectrometry, X-Ray Emission , Waste Disposal Facilities , Weather , X-Ray Diffraction
3.
Clinical and vaccine immunology ; 18(11): 1823-1833, Nov.2011.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062096

ABSTRACT

countries. Intimate adhesion of the bacteria to intestinal cells occurs via binding of the adhesin intimin to theTIR receptor exposed on cell surfaces. Here, Lactobacillus casei expressing a fragment of -intimin (L.casei-Intcv) was tested as mucosal vaccines in mice against intestinal colonization with the murine pathogenCitrobacter rodentium. Oral or sublingual immunization of C57BL/6 mice with L. casei-Intcv induced anti-IntcvIgA in feces but no IgG in sera. Conversely, anti-Intcv IgG was induced in the sera of mice after sublingualimmunization with purified Intcv. All vaccines were able to decrease C. rodentium recovery from feces. However,this reduction was more evident and sustained over time in mice immunized with L. casei-Intcv by thesublingual route. These mice also displayed an increase in interleukin 6 (IL-6) and gamma interferon (IFN- )secretion by spleen cells 10 days after infection. Additionally, oral or sublingual immunization of C3H/HePasmice, which are highly susceptible to C. rodentium infection, with L. casei-Intcv induced anti-Intcv antibodiesand significantly increased survival after challenge. Immunohistological analysis of colon sections revealedthat C. rodentium was located in deep fractions of the tissue from C3H/HePas mice immunized with L. casei whereas superficial staining was observed in colon sections from mice immunized with L. casei-Intcv. The results indicate that vaccines composed of L. casei expressing intimin may represent a promising approach and that the C3H/HePas infection model with C. rodentium can be used to evaluate potential vaccines against EPEC.


Subject(s)
Rats , Administration, Oral , Administration, Sublingual , Interferon-gamma , Spleen/anatomy & histology , Spleen/immunology , Citrobacter rodentium/pathogenicity , Lacticaseibacillus casei/genetics
4.
Clin Vaccine Immunol ; 18(11): 1823-33, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21900533

ABSTRACT

Enteropathogenic Escherichia coli (EPEC) is a common cause of diarrhea in children from developing countries. Intimate adhesion of the bacteria to intestinal cells occurs via binding of the adhesin intimin to the TIR receptor exposed on cell surfaces. Here, Lactobacillus casei expressing a fragment of ß-intimin (L. casei-Int(cv)) was tested as mucosal vaccines in mice against intestinal colonization with the murine pathogen Citrobacter rodentium. Oral or sublingual immunization of C57BL/6 mice with L. casei-Int(cv) induced anti-Int(cv) IgA in feces but no IgG in sera. Conversely, anti-Int(cv) IgG was induced in the sera of mice after sublingual immunization with purified Int(cv). All vaccines were able to decrease C. rodentium recovery from feces. However, this reduction was more evident and sustained over time in mice immunized with L. casei-Int(cv) by the sublingual route. These mice also displayed an increase in interleukin 6 (IL-6) and gamma interferon (IFN-γ) secretion by spleen cells 10 days after infection. Additionally, oral or sublingual immunization of C3H/HePas mice, which are highly susceptible to C. rodentium infection, with L. casei-Int(cv) induced anti-Int(cv) antibodies and significantly increased survival after challenge. Immunohistological analysis of colon sections revealed that C. rodentium was located in deep fractions of the tissue from C3H/HePas mice immunized with L. casei whereas superficial staining was observed in colon sections from mice immunized with L. casei-Int(cv.) The results indicate that vaccines composed of L. casei expressing intimin may represent a promising approach and that the C3H/HePas infection model with C. rodentium can be used to evaluate potential vaccines against EPEC.


Subject(s)
Adhesins, Bacterial/immunology , Bacterial Vaccines/immunology , Citrobacter rodentium/immunology , Drug Carriers , Enterobacteriaceae Infections/prevention & control , Escherichia coli Proteins/immunology , Genetic Vectors , Lacticaseibacillus casei/genetics , Adhesins, Bacterial/genetics , Administration, Oral , Administration, Sublingual , Animals , Antibodies, Bacterial/blood , Bacterial Vaccines/administration & dosage , Citrobacter rodentium/genetics , Colon/pathology , Enterobacteriaceae Infections/immunology , Enterobacteriaceae Infections/microbiology , Enterobacteriaceae Infections/mortality , Escherichia coli Proteins/genetics , Feces/microbiology , Female , Humans , Immunization/methods , Interferon-gamma/metabolism , Interleukin-6/metabolism , Leukocytes, Mononuclear/immunology , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Spleen/immunology , Survival Analysis , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology
5.
Trans R Soc Trop Med Hyg ; 105(8): 473-8, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21684567

ABSTRACT

The identification of appropriate laboratory measures to confirm clinical hypotheses is important in routine paracoccidioidomycosis medical care. The clinical records and laboratory reports of 401 paracoccidioidomycosis patients attended at the Tropical Diseases Area, Faculdade de Medicina de Botucatu, from 1974 to 2008 were reviewed. Direct mycological (DM), cell block (CB), histopathological (HP), and double immunodiffusion (DID) tests were evaluated before treatment. Typical Paracoccidioides brasiliensis yeast forms were observed in clinical specimens of 86% of the patients, but 14% were detected only by serological test. DM of 51 different tissue specimens produced 74.5% sensitivity, and 62.5% sensitivity was observed in 112 sputum samples. CB in 483 sputum samples generated 55.3% sensitivity. HP performed in 239 samples from different tissues revealed 96.7% sensitivity. Serology carried out in 351 patients and 200 healthy controls provided 90.0% sensitivity, 100.0% specificity, 100.0% positive predictive value, 85.1% negative predictive value and 93.6% accuracy. Comparisons of laboratory measurements performed in the same patient showed that sensitivity decreases from HP to DID to CB and DM, with the last two assays providing similar sensitivities. This study demonstrated that P. brasiliensis identification by HP, CB, and/or DM associated with DID is sufficient to establish the laboratorial diagnosis of paracoccidioidomycosis in practically all cases.


Subject(s)
Immunodiffusion , Paracoccidioides/isolation & purification , Paracoccidioidomycosis/immunology , Sputum/immunology , Adult , Brazil/epidemiology , Diagnostic Tests, Routine , Female , Hospitals, University , Humans , Immunodiffusion/methods , Male , Middle Aged , Paracoccidioidomycosis/diagnosis , Paracoccidioidomycosis/epidemiology , Retrospective Studies
6.
Braz. j. med. biol. res ; 44(6): 500-513, June 2011. ilus, tab
Article in English | LILACS, Sec. Est. Saúde SP | ID: lil-589971

ABSTRACT

Aluminum salts have been widely used in vaccine formulations and, after their introduction more than 80 years ago, only few vaccine formulations using new adjuvants were developed in the last two decades. Recent advances in the understanding of how innate mechanisms influence the adaptive immunity opened up the possibility for the development of new adjuvants in a more rational design. The purpose of this review is to discuss the recent advances in this field regarding the attempts to determine the molecular basis and the general mechanisms underlying the development of new adjuvants, with particular emphasis on the activation of receptors of innate immune recognition. One can anticipate that the use of these novel adjuvants will also provide a window of opportunities for the development of new vaccines.


Subject(s)
Animals , Humans , Adaptive Immunity/immunology , Immunity, Innate/immunology , Receptors, Pattern Recognition/immunology , Vaccines/immunology , Virulence Factors/immunology , Adjuvants, Immunologic/chemistry , Aluminum Compounds/immunology , Immunity, Cellular/immunology , Pertussis Vaccine/immunology , Toll-Like Receptors/immunology , Vaccines, Attenuated/immunology , Vaccines/chemistry
7.
Braz J Med Biol Res ; 44(6): 500-13, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21584443

ABSTRACT

Aluminum salts have been widely used in vaccine formulations and, after their introduction more than 80 years ago, only few vaccine formulations using new adjuvants were developed in the last two decades. Recent advances in the understanding of how innate mechanisms influence the adaptive immunity opened up the possibility for the development of new adjuvants in a more rational design. The purpose of this review is to discuss the recent advances in this field regarding the attempts to determine the molecular basis and the general mechanisms underlying the development of new adjuvants, with particular emphasis on the activation of receptors of innate immune recognition. One can anticipate that the use of these novel adjuvants will also provide a window of opportunities for the development of new vaccines.


Subject(s)
Adaptive Immunity/immunology , Immunity, Innate/immunology , Receptors, Pattern Recognition/immunology , Vaccines/immunology , Virulence Factors/immunology , Adjuvants, Immunologic/chemistry , Aluminum Compounds/immunology , Animals , Humans , Immunity, Cellular/immunology , Pertussis Vaccine/immunology , Toll-Like Receptors/immunology , Vaccines/chemistry , Vaccines, Attenuated/immunology
8.
Current Microbiology ; 60(2): 134-142, 2010.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062309

ABSTRACT

Leptospirosis is a zoonotic disease of global distribution, which affects both animals and humans. Pathogenic leptospires, the bacteria that cause this disease, require iron for their growth, and these spirochetes probably use their hemolysins, such as the sphingomyelinases, as a way to obtain this important nutrient from host red blood cells during infection. We expressed and purified the leptospiral sphingomyelinases Sph1, Sph2, Sph4, and SphH in a heterologous system. However, the recombinant proteins were not able to lyse sheep erythrocytes, despite having regular secondary structures. Transcripts for all sphingomyelinases tested were detected by RT-PCR analyses, but only Sph2 and SphH native proteins could be detected in Western blot assays using Leptospira whole extracts as well as in renal tubules of infected hamsters. Moreover, antibodies present in the serum of a human patient with laboratory-confirmed leptospirosis recognized Sph2, indicating that this sphingomyelinase is expressed and exposed to the immune system during infection in humans. However, in an animal challenge model, none of the sphingomyelinases tested conferred protection against leptospirosis.


Subject(s)
Animals , Sphingomyelins , Leptospira , Leptospirosis/microbiology , Gene Expression Profiling
9.
Mol. biotechnol ; 46(3): 279-286, 2010.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1064785

ABSTRACT

Deficiency of the lysosomal glucocerebrosidase (GCR) enzyme results in Gaucher's disease, the most common inherited storage disorder. Treatment consists of enzyme replacement therapy by the administration of recombinant GCR produced in Chinese hamster ovary cells. The production of anti-GCR antibodies has already been described with placenta-derived human GCR that requires successive chromatographic procedures. Here, we report a practical and efficient method to obtain anti-GCR polyclonal antibodies against recombinant GCR produced in Escherichia coli and further purified by a single step through nickel affinity chromatography. The purified GCR was used to immunize BALB/c mice and the induction of anti-GCR antibodies was evaluated by enzyme-linked immunosorbent assay. The specificity of the antiserum was also evaluated by western blot analysis against recombinant GCR produced by COS-7 cells or against endogenous GCR of human cell lines. GCR was strongly recognized by the produced antibodies, either as cell-associated or as secreted forms. The detected molecular masses of 59-66 kDa are in accordance to the expected size for glycosylated GCR. The GCR produced in E. coli would facilitate the production of polyclonal (shown here) and monoclonal antibodies and their use in the characterization of new biosimilar recombinant GCRs coming in the near future.


Subject(s)
Mice , Gaucher Disease/therapy , Escherichia coli/genetics , Escherichia coli/immunology , Glucosylceramidase/immunology , Recombinant Proteins/analysis , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Antibody Formation/immunology , Immune Sera
10.
Clinical and Vaccine Immunology ; 16(5): 636-645, May.2009.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062092

ABSTRACT

Pneumococcal surface protein A (PspA) and PspC are virulence factors that are involved in the adhesion of Streptococcus pneumoniae to epithelial cells and/or evasion from the immune system. Here, the immune responses induced by mucosal vaccines composed of both antigens as recombinant proteins or delivered by Lactobacillus casei were evaluated. None of the PspC vaccines protected mice against an invasive challenge with pneumococcal strain ATCC 6303. On the other hand, protection was observed for immunization with vaccines composed of PspA from clade 5 (PspA5 or L. casei expressing PspA5) through the intranasal route. The protective response was distinguished by a Th1 profile with high levels of immunoglobulin G2a production, efficient complement deposition, release of proinflammatory cytokines, and infiltration of neutrophils. Intra- nasal immunization with PspA5 elicited the highest level of protection, characterized by increased levels of secretion of interleukin-17 and gamma interferon by lung and spleen cells, respectively, and low levels of tumor necrosis factor alpha in the respiratory tract.


Subject(s)
Female , Animals , Mice , Pneumococcal Infections/genetics , Pneumococcal Infections/immunology , Pneumococcal Infections/prevention & control , Lung/immunology , Streptococcus pneumoniae/immunology , Sequence Analysis, DNA , Bacterial Proteins/genetics , Bacterial Proteins/immunology , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/immunology , Vaccines, Synthetic/genetics
11.
Microbial Pathogenesis ; 47(3): 157-163, May. 23,2009.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1064753

ABSTRACT

The differences between the immune response elicited during a self-limiting and a life-threatening lung infection with Streptococcus pneumoniae was analyzed in a mouse model of intranasal challenge using two different pneumococcal strains. M10, a serotype 11A strain, induced an early response within the first 12 h after the challenge, which was characterized by the early local secretion of TNF-á and IL-6, followed by a sharp and rapid neutrophil influx. Bacterial loads in the lungs already started to fall at 12 h after the challenge and no pneumococci could be recovered after 36 h, at the time point when the animals started to show improvement in disease symptoms. ATCC6303, a serotype 3 strain, on the other hand, showed only a late increase in local TNF-á and IL-6 levels, when bacterial growth already seems to be out of control. Although cell influx was also observed, neutrophil rise was not as marked as with M10 (type 11A). Pneumococcal loads increased constantly and bacteria started to be recovered from the blood at 30 h after the challenge. After this time point, animals showed worsening of symptoms and became lethargic. The resolution of the acute infection could be thus correlated with the early induction of proinflammatory cytokines, which could be due to the presence of a thinner polysaccharide capsule in M10 (type 11A), rendering bacterial components capable of activating the innate immune response more accessible.


Subject(s)
Animals , Rats , Streptococcus pneumoniae/immunology , Administration, Intranasal , Autoimmunity
12.
FEBS Letters ; 583(8): 1381-1385, Apr 17,2009.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062804

ABSTRACT

The role of TlyA, TlyB and TlyC proteins in the biology of Leptospira is still uncertain. Although these proteins have been considered as putative hemolysins, we demonstrate that leptospiral recombinant TlyB and TlyC do not possess hemolytic activity. However, further experiments showed that TlyC is a surface-exposed protein that seems to bind to laminin, collagen IV and fibronectin. The expression of both proteins was detected both in vitro and in vivo. Our findings suggest that TlyB and TlyC are not directly involved in hemolysis, and that TlyC may contribute to Leptospira binding to extracellular matrix (ECM) during host infection.


Subject(s)
Leptospira interrogans , Leptospirosis/microbiology , Hemolysis , Bacterial Proteins
13.
Clin Vaccine Immunol ; 16(5): 636-45, 2009 May.
Article in English | MEDLINE | ID: mdl-19279169

ABSTRACT

Pneumococcal surface protein A (PspA) and PspC are virulence factors that are involved in the adhesion of Streptococcus pneumoniae to epithelial cells and/or evasion from the immune system. Here, the immune responses induced by mucosal vaccines composed of both antigens as recombinant proteins or delivered by Lactobacillus casei were evaluated. None of the PspC vaccines protected mice against an invasive challenge with pneumococcal strain ATCC 6303. On the other hand, protection was observed for immunization with vaccines composed of PspA from clade 5 (PspA5 or L. casei expressing PspA5) through the intranasal route. The protective response was distinguished by a Th1 profile with high levels of immunoglobulin G2a production, efficient complement deposition, release of proinflammatory cytokines, and infiltration of neutrophils. Intranasal immunization with PspA5 elicited the highest level of protection, characterized by increased levels of secretion of interleukin-17 and gamma interferon by lung and spleen cells, respectively, and low levels of tumor necrosis factor alpha in the respiratory tract.


Subject(s)
Bacterial Proteins/immunology , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/immunology , Pneumonia, Pneumococcal/prevention & control , Streptococcus pneumoniae/immunology , Administration, Intranasal , Animals , Antibodies, Bacterial/immunology , Bacterial Proteins/genetics , Cells, Cultured , Cytokines/metabolism , Female , Genetic Vectors , Lacticaseibacillus casei/genetics , Leukocytes, Mononuclear/immunology , Lung/immunology , Mice , Mice, Inbred C57BL , Molecular Sequence Data , Neutrophils/immunology , Sequence Analysis, DNA , Spleen/immunology , Vaccines, Synthetic/genetics , Virulence Factors/immunology
14.
Environ Geochem Health ; 31(4): 475-85, 2009 Aug.
Article in English | MEDLINE | ID: mdl-18677575

ABSTRACT

The current paper presents the concentration, distribution, and modes of occurrence of trace elements of 13 coals from south Brazil. The samples were collected in the state of Santa Catarina. Chemical analyses and the high ash yields indicate that all studied coals are rich in mineral matter, with SiO(2) and Al(2)O(3) dominating as determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Quartz is the main mineral species and is associated with minor levels of feldspars, kaolinite, hematite, and iron-rich carbonates. The contents of trace elements, including As, Pb, Cd, Ni, Cr, Mn, Be, V, U, Zn, Li, Cu, Tl, and Ni, in coals were determined. A comparison of ranges and means of elemental concentrations in Santa Catarina, Brazil, and world coals shows that the ranges of most elements in Santa Catarina coal are very close to the usual worldwide concentration ranges in coal.


Subject(s)
Coal/analysis , Environmental Pollutants/analysis , Trace Elements/analysis , Brazil , Carbon/chemistry , Coal/classification , Coal Ash , Coal Mining , Environmental Monitoring , Humans , Particulate Matter/chemistry
15.
FEMS Immunology and Medical Microbiology ; 54(2): 245-254, Sept 17, 2008.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062812

ABSTRACT

Enteropathogenic Escherichia coli (EPEC) are frequently isolated as a cause of infantile diarrhea in developing countries. Its pathogenicity is distinguished by histopathological alterations at the site of infection, known as attaching and effacing (A/E) lesions, in which bacterial virulence factors and host proteins participate. Intimin, a bacterial adhesin expressed by all EPEC described to date, is responsible for the intimate adherence of the bacteria to host cells and is essential for the formation of A/E lesions. Mucosal vaccination may represent an efficacious intervention to prevent EPEC infection and lower morbidity and mortality rates. Strategies for mucosal vaccinations that use lactic acid bacteria for the delivery of heterologous antigens rely on their safety profile and ability to stimulate the immune system. In the present work, we have constructed Lactobacillus casei strains expressing different fragments of intimin â, a subtype that is frequently expressed by EPEC strains. Mucosal immunization of mice with L. casei expressing intimin fragments induced specific systemic and mucosal antibodies. These antibodies were able to recognize native intimin on the surface of EPEC and to inhibit in vitro EPEC binding to epithelial cells.


Subject(s)
Animals , Mice , Diarrhea, Infantile/therapy , Escherichia coli Infections/therapy , Lacticaseibacillus casei , Immunization
16.
Infect Immun ; 74(8): 4939-44, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16861686

ABSTRACT

One of the candidate proteins for a mucosal vaccine antigen against Streptococcus pneumoniae is PsaA (pneumococcal surface antigen A). Vaccines targeting mucosal immunity may raise concerns as to possible alterations in the normal microbiota, especially in the case of PsaA, which was shown to have homologs with elevated sequence identity in other viridans group streptococci. In this work, we demonstrate that intranasal immunization with a cholera toxin B subunit-PsaA fusion protein is able to protect mice against colonization with S. pneumoniae but does not significantly alter the natural oral or nasopharyngeal microbiota of mice.


Subject(s)
Antibodies, Bacterial/blood , Bacterial Proteins/administration & dosage , Cholera Toxin/administration & dosage , Pneumococcal Vaccines/administration & dosage , Recombinant Fusion Proteins/administration & dosage , Streptococcus pneumoniae/immunology , Administration, Intranasal , Animals , Bacterial Proteins/genetics , Bacterial Proteins/immunology , Bacterial Proteins/metabolism , Cholera Toxin/genetics , Cholera Toxin/immunology , Cholera Toxin/metabolism , Female , Gram-Positive Bacteria/growth & development , Gram-Positive Bacteria/isolation & purification , Immunization , Immunoglobulin A/blood , Immunoglobulin G/blood , Mice , Mice, Inbred C57BL , Mouth/microbiology , Nasopharynx/microbiology , Pneumococcal Infections/immunology , Pneumococcal Infections/microbiology , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines/immunology , Recombinant Fusion Proteins/immunology , Streptococcus pneumoniae/growth & development
17.
Infection and Immunity ; 74(8): 4939-4944, May 23, 2006.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1063417

ABSTRACT

One of the candidate proteins for a mucosal vaccine antigen against Streptococcus pneumoniae is PsaA (pneumococcal surface antigen A). Vaccines targeting mucosal immunity may raise concerns as to possible alterations in the normal microbiota, especially in the case of PsaA, which was shown to have homologs with elevated sequence identify in other viridans group streptococci. In this work, we demonstrate that intranasal immunization with a cholera toxin B subunit-PsaA fusion protein is able to protect mice against colonization with S. pneumoniae but does not significantly alter the natural oral or nasopharyngeal microbiota of mice.


Subject(s)
Female , Animals , Rats , Pneumococcal Infections/immunology , Pneumococcal Infections/microbiology , Pneumococcal Infections/prevention & control , Nasopharynx/microbiology , Streptococcus pneumoniae/growth & development , Streptococcus pneumoniae/immunology , Pneumococcal Vaccines/administration & dosage , Pneumococcal Vaccines/immunology , Gram-Positive Bacteria/growth & development , Immunoglobulin A/blood , Immunoglobulin G/blood , Bacterial Proteins/administration & dosage , Bacterial Proteins/immunology , Cholera Toxin/genetics , Cholera Toxin/immunology
18.
Journal of Medical Microbiology ; 55(4): 375-378, 2006.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1064294

ABSTRACT

Pneumococcal surface protein A (PspA) is a promising candidate for the development of cost-effective vaccines against Streptococcus pneumoniae. In the present study, BALB/c mice were immunized with DNA vaccine vectors expressing the N-terminal region of PspA. Animals immunized with a vector expressing secreted PspA developed higher levels of antibody than mice immunized with the vector expressing the antigen in the cytosol. However, both immunogens elicited similar levels of protection against intraperitoneal challenge. Furthermore, immunization with exactly the same fragment in the form of a recombinant protein, with aluminium hydroxide as an adjuvant, elicited even higher antibody levels, but this increased humoral response did not correlate with enhanced protection. These results show that DNA vaccines expressing PspA are able to elicit protection levels comparable to recombinant protein, even though total anti-PspA IgG response is considerably lower.


Subject(s)
Female , Animals , Mice , Immunoglobulin G/blood , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Pneumococcal Vaccines/genetics , Pneumococcal Vaccines/immunology , Vaccines, DNA/immunology
19.
Microbes and Infection ; 8(4): 1016-1024, 2006.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1064741

ABSTRACT

Mucosal epithelia constitute the first barriers to be overcome by pathogens during infection. The induction of protective IgA in this location is important for the prevention of infection and can be achieved through different mucosal immunization strategies. Lactic acid bacteria have been tested in the last few years as live vectors for the delivery of antigens at mucosal sites, with promising results. In this work, Streptococcus pneumoniae PsaA antigen was expressed in different species of lactic acid bacteria, such as Lactococcus lactis, Lactobacillus casei, Lactobacillus plantarum, and Lactobacillus helveticus. After nasal inoculation of C57Bl/6 mice, their ability to induce both systemic (IgG in serum) and mucosal (IgA in saliva, nasal and bronchial washes) anti-PsaA antibodies was determined. Immunization with L. lactis MG1363 induced very low levels of IgA and IgG, possibly by the low amount of PsaA expressed in this strain and its short persistence in the nasal mucosa. All three lactobacilli persisted in the nasal mucosa for 3 days and produced a similar amount of PsaA protein (150-250 ng per 109 CFU). However, L. plantarum NCDO1193 and L. helveticus ATCC15009 elicited the highest antibody response (IgA and IgG). Vaccination with recombinant lactobacilli but not with recombinant L. lactis led to a decrease in S. pneumoniae recovery from nasal mucosa upon a colonization challenge. Our results confirm that certain Lactobacillus strains have intrinsic properties that make them suitable candidates for mucosal vaccination experiments.


Subject(s)
Animals , Mice , Immunoglobulin A/analysis , Immunoglobulin A/blood , Pneumococcal Infections/immunology , Pneumococcal Infections/prevention & control , Lactobacillus/genetics , Lactobacillus/metabolism , Streptococcus pneumoniae/immunology , Adhesins, Bacterial/biosynthesis , Administration, Intranasal , Antibodies, Bacterial/blood , Respiratory Mucosa/immunology
20.
FEMS Microbiology Letters ; 227(1): 25-31, Sept 3, 2003.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062814

ABSTRACT

number of recent research works in lactic acid bacteria aim towards the design of new strains that could be used as live vectors for the delivery of antigens for oral vaccination, or other therapeutic molecules. In this work, an inducible expression system based on the Lactobacillus casei lactose operon promoter was used to express three important surface antigens of Streptococcus pneumoniae in this lactic acid bacterium: a virulence-related pneumococcal surface antigen (PsaA) and two variants of the virulence factor PspA (pneumococcal surface protein A). Expression of the three proteins was induced upon growth on lactose and strongly repressed by glucose. These proteins were produced intracellularly. Also, secretion to the growth medium was achieved by means of a fusion to the secreting and processing signals from the L. casei surface proteinase. Interestingly, while secreted PspA proteins were found in the culture supernatants, PsaA remained trapped in the cell wall. Expression of pneumococcal antigens in a food-grade organism opens an alternative for mucosal vaccination against this important pathogen. © 2003 Federation of European Microbiological Societies.


Subject(s)
Lacticaseibacillus casei/genetics , Lacticaseibacillus casei/metabolism , Streptococcus pneumoniae/genetics , Pneumococcal Vaccines/pharmacology , Pneumococcal Vaccines/genetics , Pneumococcal Vaccines/immunology , Adhesins, Bacterial , Gene Expression , Lipoproteins/genetics , Lipoproteins/immunology , Lipoproteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Carrier Proteins/genetics , Carrier Proteins/metabolism
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