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1.
Front Pharmacol ; 12: 644671, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841163

RESUMO

Hermansky-Pudlak Syndrome (HPS) is a rare, genetic, multisystem disorder characterized by oculocutaneous albinism (OCA), bleeding diathesis, immunodeficiency, granulomatous colitis, and pulmonary fibrosis. HPS pulmonary fibrosis (HPS-PF) occurs in 100% of patients with subtype HPS-1 and has a similar presentation to idiopathic pulmonary fibrosis. Upon onset, individuals with HPS-PF have approximately 3 years before experiencing signs of respiratory failure and eventual death. This review aims to summarize current research on HPS along with its associated pulmonary fibrosis and its implications for the development of novel treatments. We will discuss the genetic basis of the disease, its epidemiology, and current therapeutic and clinical management strategies. We continue to review the cellular processes leading to the development of HPS-PF in alveolar epithelial cells, lymphocytes, mast cells, and fibrocytes, along with the molecular mechanisms that contribute to its pathogenesis and may be targeted in the treatment of HPS-PF. Finally, we will discuss emerging new cellular and molecular approaches for studying HPS, including lentiviral-mediated gene transfer, induced pluripotent stem cells (iPSCs), organoid and 3D-modelling, and CRISPR/Cas9-based gene editing approaches.

2.
Microb Pathog ; 149: 104580, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33080359

RESUMO

Leptospirosis is a global disease that affects humans and animals, impacting public health and the economy. The symptoms caused by Leptospira infection can vary from mild to severe, affecting liver, lungs, and kidneys. The host-pathogen interaction in leptospirosis is still poorly understood, but there is evidence for the role of the host immune response in the pathogenesis. Chemokines are a family of structurally-related low-molecular-mass proteins (8-14 kDa) that signal the recruitment of leukocytes. In this study the profile of 22 chemokines were evaluated in liver and kidney of three mice strains with different phenotypes of susceptibility to leptospirosis. We extended our previously reported observations showing that expression of chemokines with homeostatic function, activation and chemotaxis of leukocytes are essential to modulate and to induce resistance to leptospirosis. Our findings support that an early induction of CXC chemokines in resistant BALB/c mice can be associated with the control of the infection. The correlation of chemokine expression between liver and kidney observed in BALB/c suggests that a balance of chemokine induction in the organs may contribute to resistance to leptospirosis.


Assuntos
Leptospirose , Animais , Quimiocinas , Rim , Fígado , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H
3.
PLoS One ; 15(3): e0230460, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32218590

RESUMO

Pathogenic spirochetes from genus Leptospira are etiologic agents of leptospirosis. Cellular vaccines against Leptospira infection often elicit mainly response against the LPS antigen of the serovars present in the formulation. There is no suitable protein candidate capable of replacing whole-cell vaccines, thus requiring new approaches on vaccine development to improve leptospirosis prevention. Our goal was to develop a whole-cell vaccine sorovar-independent based on LPS removal and conservation of protein antigens exposure, to evaluate the protective capacity of monovalent or bivalent vaccines against homologous and heterologous virulent Leptospira in hamster. Leptospire were subjected to heat inactivation, or to LPS extraction with butanol and in some cases further inactivation with formaldehyde. Hamsters were immunized and challenged with homologous or heterologous virulent serovars, blood and organs were collected from the survivors for bacterial quantification, chemokine evaluation, and analysis of sera antibody reactivity and cross-reactivity by Western blot. Immunization with either heated or low LPS vaccines with serovar Copenhageni or Canicola resulted in 100% protection of the animals challenged with homologous virulent bacteria. Notably, different from the whole-cell vaccine, the low LPS vaccines produced with serovar Canicola provided only partial protection in heterologous challenge with the virulent Copenhageni serovar. Immunization with bivalent formulation results in 100% protection of immunized animals challenged with virulent serovar Canicola. All vaccines produced were able to eliminate bacteria from the kidney of challenged animals. All the vaccines raised antibodies capable to recognize antigens of serovars not present in the vaccine formulation. Transcripts of IFNγ, CXCL16, CCL5, CXCL10, CXCR6, and CCR5, increased in all immunized animals. Conclusion: Our results showed that bivalent vaccines with reduced LPS may be an interesting strategy for protection against heterologous virulent serovars. Besides the desirable multivalent protection, the low LPS vaccines are specially promising due to the expected lower reatogenicity.


Assuntos
Vacinas Bacterianas , Leptospira/imunologia , Leptospirose/imunologia , Lipopolissacarídeos/química , Vacinação , Animais , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/química , Vacinas Bacterianas/imunologia , Cricetinae , Leptospira/química , Leptospirose/prevenção & controle
4.
Microb Pathog, v. 149, 104580, dez. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3285

RESUMO

Leptospirosis is a global disease that affects humans and animals, impacting public health and the economy. The symptoms caused by Leptospira infection can vary from mild to severe, affecting liver, lungs, and kidneys. The host-pathogen interaction in leptospirosis is still poorly understood, but there is evidence for the role of the host immune response in the pathogenesis. Chemokines are a family of structurally-related low-molecular-mass proteins (8–14 kDa) that signal the recruitment of leukocytes. In this study the profile of 22 chemokines were evaluated in liver and kidney of three mice strains with different phenotypes of susceptibility to leptospirosis. We extended our previously reported observations showing that expression of chemokines with homeostatic function, activation and chemotaxis of leukocytes are essential to modulate and to induce resistance to leptospirosis. Our findings support that an early induction of CXC chemokines in resistant BALB/c mice can be associated with the control of the infection. The correlation of chemokine expression between liver and kidney observed in BALB/c suggests that a balance of chemokine induction in the organs may contribute to resistance to leptospirosis.

5.
PloS One, v. 15, n. 3, e0230460, mar. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2989

RESUMO

Pathogenic spirochetes from genus Leptospira are etiologic agents of leptospirosis. Cellular vaccines against Leptospira infection often elicit mainly response against the LPS antigen of the serovars present in the formulation. There is no suitable protein candidate capable of replacing whole-cell vaccines, thus requiring new approaches on vaccine development to improve leptospirosis prevention. Our goal was to develop a whole-cell vaccine sorovar-independent based on LPS removal and conservation of protein antigens exposure, to evaluate the protective capacity of monovalent or bivalent vaccines against homologous and heterologous virulent Leptospira in hamster. Leptospire were subjected to heat inactivation, or to LPS extraction with butanol and in some cases further inactivation with formaldehyde. Hamsters were immunized and challenged with homologous or heterologous virulent serovars, blood and organs were collected from the survivors for bacterial quantification, chemokine evaluation, and analysis of sera antibody reactivity and cross-reactivity by Western blot. Immunization with either heated or low LPS vaccines with serovar Copenhageni or Canicola resulted in 100% protection of the animals challenged with homologous virulent bacteria. Notably, different from the whole-cell vaccine, the low LPS vaccines produced with serovar Canicola provided only partial protection in heterologous challenge with the virulent Copenhageni serovar. Immunization with bivalent formulation results in 100% protection of immunized animals challenged with virulent serovar Canicola. All vaccines produced were able to eliminate bacteria from the kidney of challenged animals. All the vaccines raised antibodies capable to recognize antigens of serovars not present in the vaccine formulation. Transcripts of IFN?, CXCL16, CCL5, CXCL10, CXCR6, and CCR5, increased in all immunized animals. Conclusion: Our results showed that bivalent vaccines with reduced LPS may be an interesting strategy for protection against heterologous virulent serovars. Besides the desirable multivalent protection, the low LPS vaccines are specially promising due to the expected lower reatogenicity

6.
Andrology, v. 7, n. 3, p. 373-381, mai. 2019
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2725

RESUMO

Background Sperm DNA integrity is crucial for transmission of genetic information to future generations and DNA damage can occur during chromatin packaging. Chromatin packaging involves the replacement of somatic nucleosomal histones by nuclear proteins called protamines. Protamine 1 (PRM1) is transcribed and translated in spermatids of all mammals; however, protamine 2 (PRM2) is transcribed in low levels in spermatids and it is not yet described in bull mature spermatozoa. Objectives The aim of this study was to assess gene and protein expression of PRM2 and corroborate gene and protein expression of PRM1 in bull spermatozoa and testis. Materials and methods For this purpose, absolute q-RT-PCR was performed to calculate the number of copies of PRM1 and PRM2 mRNAs in bovine epididymal spermatozoa and testicular tissue. Western blot and mass spectrometry were performed to identify PRM1 and PRM2 in samples of bovine epididymal spermatozoa. Samples of bovine testicular tissue were collected to identify PRM1 and PRM2 by immunohistochemistry. Results We evaluated that the number of PRM1 mRNA copies was about hundred times higher than PRM2 mRNA copies in sperm and testicular samples (p < 0.0001). In addition, we estimated the PRM1: PRM2 ratio based on mRNA number of copies. In spermatozoa, the ratio was 1: 0.014, and in testicle, the ratio was 1: 0.009. We also evaluated the immunolocalization for PRM1 and PRM2 in bovine testis, and both proteins were detected in spermatids. Western blot and mass spectrometry in bovine epididymal spermatozoa confirmed these results. Conclusion Our work identifies, for the first time, PRM2 in bovine epididymal spermatozoa and in testis. Further studies are still needed to understand the role of PRM2 on the chromatin of the spermatozoa and to verify how possible changes in PRM2 levels may influence the bull fertility.

7.
Acta Trop ; 140: 193-201, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240208

RESUMO

The Schistosoma mansoni transcriptome revealed new members of the dynein light chain family (DLC/LC8). The antigenicity and immunogenicity of these proteins, and their potential as vaccine candidates were investigated. Two DLC genes (DLC12_JI392413.1 and DLC13_JI387686.1) were cloned and the recombinant proteins produced in E. coli. The immunization of mice with the rDLCs, using alhydrogel as adjuvant, resulted in high titers of antibodies, indicated that these proteins are highly immunogenic. The anti-DLCs antibodies presented cross reactivity with both recombinant antigens and also recognized proteins from S. mansoni adult worm extracts. The DLC12 and DLC13 immunized animals were challenged by infection with cercariae and a protective profile was observed in three different assays, with a significant decreased in worm burden, of 43% and 51% respectively, when compared to the non-vaccinated group. The granulomas formation due to egg retention in the hepatic tissues was evaluated 45 days after infection. Smaller granulomas were observed in the liver of DLC immunized animals, up to 70% reduction in comparison to the granulomas size in the non-vaccinated animals. Fifty-five days after infection, the average size of the hepatic granulomas was still 25-35% smaller in the DLCs vaccinated groups. The interference of DLC immunization on the hepatic granuloma formation may reflect the lower worm burden and consequent decrease on the number of eggs retained in the liver, resulting in lower pro-inflammatory level in the tissue. The protective effect of DLCs immunization, decreasing the worm burden and delaying the rate of granuloma formation, suggests that these antigens should be further studied as potential vaccine candidates.


Assuntos
Antígenos de Helmintos/imunologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/prevenção & controle , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Vacinação , Vacinas de DNA/imunologia
8.
PLoS One ; 9(7): e101678, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25047537

RESUMO

The prokaryotic ubiquitous Toxin-Antitoxin (TA) operons encode a stable toxin and an unstable antitoxin. The most accepted hypothesis of the physiological function of the TA system is the reversible cessation of cellular growth under stress conditions. The major TA family, VapBC is present in the spirochaete Leptospira interrogans. VapBC modules are classified based on the presence of a predicted ribonucleasic PIN domain in the VapC toxin. The expression of the leptospiral VapC in E. coli promotes a strong bacterial growth arrestment, making it difficult to express the recombinant protein. Nevertheless, we showed that long term induction of expression in E. coli enabled the recovery of VapC in inclusion bodies. The recombinant protein was successfully refolded by high hydrostatic pressure, providing a new method to obtain the toxin in a soluble and active form. The structural integrity of the recombinant VapB and VapC proteins was assessed by circular dichroism spectroscopy. Physical interaction between the VapC toxin and the VapB antitoxin was demonstrated in vivo and in vitro by pull down and ligand affinity blotting assays, respectively, thereby indicating the ultimate mechanism by which the activity of the toxin is regulated in bacteria. The predicted model of the leptospiral VapC structure closely matches the Shigella's VapC X-ray structure. In agreement, the ribonuclease activity of the leptospiral VapC was similar to the activity described for Shigella's VapC, as demonstrated by the cleavage of tRNAfMet and by the absence of unspecific activity towards E. coli rRNA. This finding suggests that the cleavage of the initiator transfer RNA may represent a common mechanism to a larger group of bacteria and potentially configures a mechanism of post-transcriptional regulation leading to the inhibition of global translation.


Assuntos
Antitoxinas/metabolismo , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Leptospira interrogans/metabolismo , Glicoproteínas de Membrana/metabolismo , RNA de Transferência de Metionina/metabolismo , Ribonucleases/metabolismo , Sequência de Aminoácidos , Animais , Antitoxinas/química , Antitoxinas/genética , Antitoxinas/isolamento & purificação , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Toxinas Bacterianas/isolamento & purificação , Clonagem Molecular , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/isolamento & purificação , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Leptospira interrogans/química , Leptospira interrogans/genética , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/isolamento & purificação , Camundongos Endogâmicos BALB C , Modelos Moleculares , Dados de Sequência Molecular , Óperon , Redobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
9.
J Biotechnol ; 168(4): 511-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24084635

RESUMO

Schistosomiasis is an important parasitic disease, with about 240 million people infected worldwide. Humans and animals can be infected, imposing an enormous social and economic burden. The only drug available for chemotherapy, praziquantel, does not control reinfections, and an efficient vaccine for prophylaxis is still missing. However, the tegumental protein Sm29 of Schistosoma mansoni was shown to be a promising antigen to compose an anti-schistosomiasis vaccine. Though, recombinant Sm29 is expressed in Escherichia coli as insoluble inclusion bodies requiring an efficient process of refolding, thus, hampering its production in large scale. We present in this work studies to refold the recombinant Sm29 using high hydrostatic pressure, a mild condition to dissociate aggregated proteins, leading to refolding on a soluble conformation. Our studies resulted in high yield of rSm29 (73%) as a stably soluble and structured protein. The refolded antigen presented protective effect against S. mansoni development in immunized mice. We concluded that the refolding process by application of high hydrostatic pressure succeeded, and the procedure can be scaled-up, allowing industrial production of Sm29.


Assuntos
Antígenos de Helmintos/imunologia , Proteínas de Helminto/imunologia , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes/biossíntese , Schistosoma/imunologia , Esquistossomose/prevenção & controle , Vacinas/biossíntese , Animais , Dicroísmo Circular , Escherichia coli/genética , Humanos , Corpos de Inclusão/genética , Corpos de Inclusão/patologia , Camundongos , Dobramento de Proteína , Proteínas Recombinantes/genética , Schistosoma/genética , Schistosoma/patogenicidade , Esquistossomose/genética , Esquistossomose/imunologia
10.
São Paulo; s.n; 2010. 177 p.
Tese em Português | Sec. Est. Saúde SP | ID: biblio-1079163

RESUMO

A leptospirose é uma doença de importância global que acomete humanos e alguns animais, causada por bactérias do gênero Leptospira. No Brasil são notificados cerca de três mil casos da doença em humanos por ano e 10% chegam a óbito. A leptospirose é um problema sério especialmente nos grandes centros urbanos devido á quantidade de roedores que são reservatórios de leptospira. A melhor forma de controle da leptospirose seria a prevenção com medidas de saneamento básico e conscientização da população. O projeto para sequenciamento do genoma da Leptospira Interrogans sorovar Copenhageni coordenado por um grupo de pesquisadores do Instituto Butantan e projeto Genoma funcional para desenvolvimento da vacina contra leptospirose, no qual nosso trabalho se insere, foram incentivados para necessidade de uma vacina eficaz para humanos...


Leptospirosis is a disease of global importance that affects humans and animals, caused by bacteria of the genus Leptospira. In Brasil, about three thousands human cases are notified every year 10% of the patients die. Leptospirosis is a serious issue, especialy in urban centre, due to the amount of rodents that are reservoirs of leptospira. The best way to control leptospirosis prevention with better sanitation measures and public awereness. The project for sequencing the genome of Leptospira interrogans serovar Copenhageni, coordinated by a group of researchers from Instituto Butantan and the Funtional genome for vaccine development, in wich our work belong, were encouraged by the need of an effective vaccine for humans...


Assuntos
Cricetinae , Camundongos , Antígenos/administração & dosagem , Antígenos/isolamento & purificação , Antígenos/uso terapêutico , Leptospira interrogans serovar australis/genética , Leptospira interrogans serovar australis/isolamento & purificação , Leptospirose/prevenção & controle , Leptospirose/transmissão , Expressão Gênica/genética , Expressão Gênica/imunologia , Fatores de Virulência/genética , Fatores de Virulência/imunologia
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