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1.
Cell Physiol Biochem ; 55(4): 460-476, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34363385

RESUMO

BACKGROUND/AIMS: Cancer is the second most deadly disease in the world. The bladder cancer is one of the most aggressive types and shows a continuous increase in the number of cases. The use of bacteria as live vectors to deliver molecules directly to the tumor is a promising tool and has been used as an adjuvant treatment against several types of cancer. The aim of this study was to investigate the antitumor effect of Interleukin 2 (IL-2), TNF-related apoptosis-inducing ligand (TRAIL) and protein MIX against murine bladder cancer cells, lineage MB49. METHODS: The attenuated Salmonella strain SL3261 was transformed by inserting the IL-2 and TRAIL genes. The effects of proteins on cell viability (MTT method), cell morphology (optical microscopy), cell recovery (clonogenic assay), cell membrane (lactate dehydrogenase release - LDH), on oxidative stress pathway (levels of nitric oxide, NO) and apoptosis (flow cytometry and high resolution epifluorescence images) were evaluated at intervals of 24 and 48 hours of action. RESULTS: The results showed that there was a decrease in cell viability via damage to the cell membrane, alteration of cell morphology, non-recovery of cells, increase in the production of NO and incubate for of cells in the state of apoptosis in the two periods analyzed. CONCLUSION: The data presented suggest that IL-2, TRAIL and their MIX proteins in MB49 cells have cytotoxic potential and that this is associated with oxidative stress and apoptosis pathways. These results may contribute to the development of new therapeutic strategies for bladder cancer.


Assuntos
Interleucina-2/imunologia , Microrganismos Geneticamente Modificados/imunologia , Salmonella/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/terapia , Animais , Linhagem Celular Tumoral , Interleucina-2/biossíntese , Interleucina-2/genética , Camundongos , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/metabolismo , Salmonella/genética , Salmonella/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/biossíntese , Ligante Indutor de Apoptose Relacionado a TNF/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
2.
Sci Rep ; 11(1): 17214, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446765

RESUMO

Salmonella enterica serovar Gallinarum is a host-restricted bacterial pathogen that causes a serious systemic disease exclusively in birds of all ages. Salmonella enterica serovar Typhimurium is a host-generalist serovar. Dendritic cells (DCs) are key antigen-presenting cells that play an important part in Salmonella host-restriction. We evaluated the differential response of chicken blood monocyte-derived dendritic cells (chMoDCs) exposed to S. Gallinarum or S. Typhimurium. S. Typhimurium was found to be more invasive while S. Gallinarum was more cytotoxic at the early phase of infection and later showed higher resistance against chMoDCs killing. S. Typhimurium promoted relatively higher upregulation of costimulatory and other immune function genes on chMoDCs in comparison to S. Gallinarum during early phase of infection (6 h) as analyzed by real-time PCR. Both Salmonella serovars strongly upregulated the proinflammatory transcripts, however, quantum was relatively narrower with S. Gallinarum. S. Typhimurium-infected chMoDCs promoted relatively higher proliferation of naïve T-cells in comparison to S. Gallinarum as assessed by mixed lymphocyte reaction. Our findings indicated that host restriction of S. Gallinarum to chicken is linked with its profound ability to interfere the DCs function. Present findings provide a valuable roadmap for future work aimed at improved vaccine strategies against this pathogen.


Assuntos
Células Dendríticas/imunologia , Monócitos/imunologia , Salmonella typhimurium/imunologia , Salmonella/imunologia , Animais , Antígeno B7-1/genética , Antígeno B7-1/imunologia , Antígenos CD40/genética , Antígenos CD40/imunologia , Galinhas , Citocinas/genética , Citocinas/imunologia , Citotoxicidade Imunológica/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Expressão Gênica/imunologia , Interações Hospedeiro-Patógeno/imunologia , Viabilidade Microbiana/imunologia , Monócitos/citologia , Salmonella/fisiologia , Salmonella typhimurium/fisiologia , Especificidade da Espécie , Linfócitos T/imunologia , Linfócitos T/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia
3.
Emerg Microbes Infect ; 10(1): 1471-1480, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34197273

RESUMO

Food-borne infections with Salmonella are among the most common causes of human diseases worldwide, and infections with the serovar Infantis are becoming increasingly important. So far, diverse phenotypes and genotypes of S. Infantis have been reported. Therefore, the present study aimed to investigate the infection dynamics of two different S. Infantis strains in broilers. For this purpose, 15 birds were infected on day 2 of life with 108 CFU/ml of a pESI+ or a pESI- S. Infantis strain, respectively. Ten uninfected birds served as in-contact birds to monitor transmission. In both groups, an increase of infection was observed from 7 days of age onwards, reaching its peak at 28 days. However, the pESI+ strain proved significantly more virulent being re-isolated from most cloacal swabs and organs by direct plating. In contrast, the pESI- strain could be re-isolated from cloacal swabs and caeca only when enrichment was applied. Although the excretion of this strain was limited, the transmission level to in-contact birds was similar to the pESI+ strain. Differences in infection dynamics were also reflected in the antibody response: whereas the pESI+ strain provoked a significant increase in antibodies, antibody levels following infection with the pESI- strain remained in the range of negative control birds. The actual findings provide for the first time evidence of S. Infantis strain-specific infectivity in broilers and confirm previous observations in the field regarding differences in persistence on farms and resistance against disinfectants.


Assuntos
Plasmídeos/genética , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella/genética , Animais , Anticorpos Antibacterianos/sangue , Galinhas , Patrimônio Genético , Plasmídeos/metabolismo , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/transmissão , Salmonella/classificação , Salmonella/imunologia , Salmonella/patogenicidade , Salmonelose Animal/sangue , Salmonelose Animal/transmissão , Virulência
4.
Res Vet Sci ; 138: 125-136, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34139624

RESUMO

Salmonella enterica subspecies diarizonae serovar 61:(k):1, 5, (7) (sheep associated S. diarizonae, SASd) is the most common Salmonella serotype identified in sheep flocks. Despite the involvement with animal and human infections, there is limited information regarding virulence profiles of SASds and their antibiotic resistance gene complement, particularly for those circulating in the U.S. In this study, we genetically characterized three SASds, 20-265, 20-269, and 20-312, isolated from sheep placental tissues during an abortion storm affecting a flock in Connecticut during 2020. SASds were the only bacteria isolated from analyzed sheep tissues. The isolates were sensitive to all the antibiotics tested, but all these SASd isolates carry the aminoglycoside resistance gene, aac(6')-Iaa, and a chromosomal substitution in the parC gene. The proportion of pseudogenes (5.3-5.5%) was similar among the isolates, and these SASds carry IncX1 type plasmids. Comparing with the SASds isolates from Enterobase, the three isolates showed an identical genomic virulence profile carrying virulence genes in the conserved set of other SASd isolates except for steC, iagB, iacP, sseI, and slrP genes. In the SNP-based phylogenetic analysis, SASd sequences were grouped into group A-C, and the group C was further subdivided into subgroup C1-C6. The three isolates clustered with other SASd isolates from the U.S. and Canada in subgroup C6. SASd isolates in the identical phylogenetic groups tended to have similar geographical origin. The results of our study did not provide conclusive evidence about which are the genetic traits that trigger SASds to become virulent in sheep, but our data will provide a point for comparative studies of this Salmonella serovar.


Assuntos
Aborto Animal/microbiologia , Salmonelose Animal/microbiologia , Salmonella/genética , Doenças dos Ovinos/microbiologia , Ovinos/microbiologia , Aborto Animal/epidemiologia , Animais , Farmacorresistência Bacteriana/genética , Feminino , Humanos , Filogenia , Placenta/microbiologia , Plasmídeos/genética , Polimorfismo de Nucleotídeo Único/genética , Gravidez , Salmonella/imunologia , Salmonella/isolamento & purificação , Salmonella/patogenicidade , Salmonelose Animal/epidemiologia , Sorogrupo , Doenças dos Ovinos/epidemiologia , Estados Unidos/epidemiologia , Virulência/genética
5.
Front Immunol ; 12: 667897, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34108968

RESUMO

A therapy that includes an oral vaccine for type 1 diabetes (T1D) using live attenuated Salmonella MvP728 (ΔhtrA/ΔpurD), cytokines (IL10 and TGFß) and preproinsulin (PPI) antigen in combination with a sub-therapeutic dose of anti-CD3 mAb was developed by our team. The vaccine combination therapy reduced insulitis and prevented and reversed diabetes in non-obese diabetic (NOD) mice. Here, we show the effectiveness of an alternative Salmonella mutant (ΔmsbB) as a carrier strain, which is anticipated to have lower risks of an inflammatory response and septicemia as a result of modification in the lipopolysaccharide (LPS) via detoxification of lipid A. This mutant strain proved to have highly reduced pathogenic side effects. Salmonella strain ΔmsbB expressed autoantigens and in combination with cytokines and anti-CD3 mAb, successfully prevented and reversed T1D to levels comparable to the previously used carrier strain ΔhtrA/ΔpurD. Additionally, the Salmonella msbB mutant resulted in higher rates of host cell infection. These results further demonstrate the potential of an oral Salmonella-based combined therapy in the treatment of early T1D.


Assuntos
Aciltransferases/genética , Proteínas de Bactérias/genética , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/prevenção & controle , Vetores Genéticos , Mutação , Salmonella/genética , Vacinas de DNA/administração & dosagem , Administração Oral , Animais , Anticorpos Monoclonais/administração & dosagem , Biomarcadores/sangue , Complexo CD3/antagonistas & inibidores , Complexo CD3/imunologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Modelos Animais de Doenças , Feminino , Insulina/administração & dosagem , Insulina/genética , Interleucina-10/administração & dosagem , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos NOD , Precursores de Proteínas/administração & dosagem , Precursores de Proteínas/genética , Células RAW 264.7 , Salmonella/imunologia , Salmonella/patogenicidade , Fator de Crescimento Transformador beta1/administração & dosagem , Fator de Crescimento Transformador beta1/genética , Vacinas Atenuadas/administração & dosagem , Vacinas de DNA/genética , Vacinas de DNA/imunologia
6.
Nature ; 594(7863): 413-417, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33981034

RESUMO

Humans and their microbiota have coevolved a mutually beneficial relationship in which the human host provides a hospitable environment for the microorganisms and the microbiota provides many advantages for the host, including nutritional benefits and protection from pathogen infection1. Maintaining this relationship requires a careful immune balance to contain commensal microorganisms within the lumen while limiting inflammatory anti-commensal responses1,2. Antigen-specific recognition of intestinal microorganisms by T cells has previously been described3,4. Although the local environment shapes the differentiation of effector cells3-5 it is unclear how microbiota-specific T cells are educated in the thymus. Here we show that intestinal colonization in early life leads to the trafficking of microbial antigens from the intestine to the thymus by intestinal dendritic cells, which then induce the expansion of microbiota-specific T cells. Once in the periphery, microbiota-specific T cells have pathogenic potential or can protect against related pathogens. In this way, the developing microbiota shapes and expands the thymic and peripheral T cell repertoire, allowing for enhanced recognition of intestinal microorganisms and pathogens.


Assuntos
Células Dendríticas/imunologia , Microbioma Gastrointestinal/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Timo/citologia , Timo/imunologia , Envelhecimento/imunologia , Animais , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/metabolismo , Receptor 1 de Quimiocina CX3C/metabolismo , DNA Bacteriano/análise , Células Dendríticas/metabolismo , Escherichia coli/imunologia , Feminino , Masculino , Camundongos , Especificidade de Órgãos , Salmonella/imunologia , Simbiose/imunologia , Timo/metabolismo
7.
Front Immunol ; 12: 648710, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868285

RESUMO

The global rise of antibiotic-resistant strains of Salmonella has necessitated the development of alternative therapeutic strategies. Recent studies have shown that targeting host factors may provide an alternative approach for the treatment of intracellular pathogens. Host-directed therapy (HDT) modulates host cellular factors that are essential to support the replication of the intracellular pathogens. In the current study, we identified Gefitinib as a potential host directed therapeutic drug against Salmonella. Further, using the proteome analysis of Salmonella-infected macrophages, we identified EGFR, a host factor, promoting intracellular survival of Salmonella via mTOR-HIF-1α axis. Blocking of EGFR, mTOR or HIF-1α inhibits the intracellular survival of Salmonella within the macrophages and in mice. Global proteo-metabolomics profiling indicated the upregulation of host factors predominantly associated with ATP turn over, glycolysis, urea cycle, which ultimately promote the activation of EGFR-HIF1α signaling upon infection. Importantly, inhibition of EGFR and HIF1α restored both proteomics and metabolomics changes caused by Salmonella infection. Taken together, this study identifies Gefitinib as a host directed drug that holds potential translational values against Salmonella infection and might be useful for the treatment of other intracellular infections.


Assuntos
Gefitinibe/farmacologia , Metabolômica/métodos , Proteômica/métodos , Infecções por Salmonella/prevenção & controle , Salmonella/efeitos dos fármacos , Animais , Células Cultivadas , Receptores ErbB/imunologia , Receptores ErbB/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/imunologia , Inibidores de Proteínas Quinases/farmacologia , Salmonella/imunologia , Salmonella/fisiologia , Infecções por Salmonella/imunologia , Infecções por Salmonella/microbiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Células THP-1
8.
PLoS One ; 16(4): e0247938, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33822791

RESUMO

Salmonella is a zoonotic pathogen that persists in poultry. Salmonella vaccines that can be delivered in-ovo can be cost-effective and can decrease Salmonella load in poultry. This study evaluates the efficacy of a Salmonella chitosan-nanoparticle (CNP) vaccine, administered in-ovo, in broilers. CNP vaccine was synthesized with Salmonella Enteritidis (SE) outer-membrane-proteins (OMPs) and flagellin proteins. At embryonic-d18, one-hundred-thirty-six eggs were injected with 200µl PBS or 1000µg CNP into the amniotic cavity. At d1-of-age, 132 chicks were allocated in 6 pens/treatment with 11 chicks/pen. At d7, birds were orally challenged with 1×109 CFU/bird SE. At d1, 8h-post-challenge, d14, and d21, serum anti-SE-OMPs IgY were analyzed. At d14 and d21, cloacal swabs and bile anti-SE-OMPs IgA, CD4+/CD8+-T-cell ratios, and ceca SE loads were analyzed. At d21, cecal tonsil IL-1ß, IL-10, and iNOS mRNA were analyzed. Body-weight-gain (BWG) and feed-conversion-ratio (FCR) were recorded weekly. Data were analyzed by Student's t-test at P<0.05. There were no significant differences in BWG or FCR between vaccinated birds compared to control. At d1, CNP-vaccinated birds had 5.62% greater levels (P<0.05) of anti-SE-OMPs IgY, compared to control. At 8h-post-challenge, CNP-vaccinated birds had 6.39% greater levels (P<0.05) of anti-SE-OMPs IgY, compared to control. At 2wk-post-challenge, CNP-vaccinated birds had 7.34% lower levels (P<0.05) of anti-SE-OMPs IgY, compared to control. At 1wk-post-challenge, CNP-vaccinated birds had 15.30% greater levels (P<0.05) of bile anti-SE-OMPs IgA, compared to control. At d14 and d21, CNP-vaccinated birds had 0.62 and 0.85 Log10 CFU/g, decreased SE ceca load (P<0.05), respectively, compared to control. There were no significant differences in CD4+/CD8+-T-cell ratios between vaccinated birds compared to control. There were no significant differences in IL-1ß, IL-10, iNOS mRNA between vaccinated birds compared to control. Findings demonstrate that the in-ovo administration of CNP vaccine can induce an antigen-specific immune response against SE and can decrease SE cecal load in broilers.


Assuntos
Galinhas/imunologia , Nanopartículas/uso terapêutico , Vacinas contra Salmonella/imunologia , Animais , Quitosana/imunologia , Quitosana/farmacologia , Flagelina/imunologia , Nanopartículas/química , Doenças das Aves Domésticas/prevenção & controle , Salmonella/imunologia , Salmonella/patogenicidade , Salmonelose Animal/imunologia , Salmonella enteritidis/imunologia , Vacinas/administração & dosagem
9.
Vet Immunol Immunopathol ; 236: 110236, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33892385

RESUMO

Disease outbreaks heavily impact the economic viability of animal industries. Little is known about the mechanisms of immune system-related diseases in geese. Toll-like receptors (TLRs) play a major role in the anti-inflammatory immunity process in most animal species, but they have not been studied in the Magang goose. To elucidate the role of TLRs, reverse transcription polymerase chain reaction (RT-PCR) and PCR amplification of cDNA ends (Smart RACE) were used to clone the Magang goose TLR5 gene (mgTLR5). The full-length cDNA of mgTLR5 was 2967 bp in length, including a 5'-terminal untranslated region (UTR) of 215 bp, a 3'-terminal UTR of 384 bp, and an open reading frame of 2583 bp that encodes a protein of 860 amino acids. Structurally, mgTLR5 has a toll/interleukin-receptor (TIR) domain, a transmembrane domain, and seven leucine-rich repeats (LRRs) domains. Homology alignment of TLR5 and its TIR domains with other species revealed that mgTLR5 shared 98 % and 81.3 % of sequence similarity with white goose TLR5 and chicken TLR5, respectively. Quantitative RT-PCR showed that the mgTLR5 gene of the goose is widely expressed in all tested tissues, with the highest expression in the kidney and spleen. The increase in NF-κB promoter activity stimulated by flagellin was dependent on mgTLR5 expression in 293 T cells. Salmonella pullorum and flagellin significantly upregulated the expression of TLR5, IL-8, and IL-1 mRNA in peripheral blood mononucleotide cells of Magang goose cultured in vitro. Stimulation by S. pullorum for 24 h upregulated mgTLR5 expression in the cecum and kidney. We conclude that Magang goose TLR5 is a functional TLR5 homologue of the protein in other species and plays an important role in bacterial recognition.


Assuntos
Gansos/genética , Gansos/imunologia , Receptor 5 Toll-Like/genética , Receptor 5 Toll-Like/imunologia , Animais , Clonagem Molecular , Flagelina/farmacologia , Regulação da Expressão Gênica , Células HEK293 , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Salmonella/imunologia
10.
Front Immunol ; 12: 615930, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33717106

RESUMO

Since the first reported spontaneous regression of tumors in patients with streptococcus infection, cancer biological therapy was born and it evolved into today's immunotherapy over the last century. Although the original strategy was unable to impart maximal therapeutic benefit at the beginning, it laid the foundations for the development of immune checkpoint blockade and CAR-T which are currently used for cancer treatment in the clinics. However, clinical applications have shown that current cancer immunotherapy can cause a series of adverse reactions and are captious for patients with preexisting autoimmune disorders. Salmonellae was first reported to exert antitumor effect in 1935. Until now, numerous studies have proved its potency as an antitumor agent in the near future. In this review, we summarize the currently available data on the antitumor effects of Salmonella, and discussed a possibility of integrating Salmonella into cancer immunotherapy to overcome current obstacles.


Assuntos
Terapia Biológica/métodos , Imunoterapia/métodos , Neoplasias/terapia , Salmonella , Animais , Apoptose/genética , Apoptose/imunologia , Autofagia/genética , Autofagia/imunologia , Ensaios Clínicos como Assunto , Terapia Combinada/métodos , Citocinas/metabolismo , Gerenciamento Clínico , Humanos , Mediadores da Inflamação , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Salmonella/imunologia , Resultado do Tratamento , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
11.
Avian Pathol ; 50(2): 109-111, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33464927

RESUMO

The use of novel vector vaccines (viral, bacterial and apicomplexan) can have a significant impact on the control of poultry disease. They offer a cost effective, convenient and effective means of mass vaccine delivery combined with the ability to switch on both antibody and cell-mediated immunity. In addition, recent viral vector constructs have enabled farmers to vaccinate against up to three important pathogens with a single in ovo administration. As the technology develops, it is likely that this means of vaccine administration will be utilized further and it will play a key role in the control of both existing and new emerging diseases of poultry in the future.


Assuntos
Doenças Transmissíveis Emergentes/prevenção & controle , Eimeria/imunologia , Vírus da Varíola das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , Salmonella/imunologia , Vacinas/administração & dosagem , Animais , Doenças Transmissíveis Emergentes/patologia , Vírus da Varíola das Aves Domésticas/genética , Vetores Genéticos , Imunidade Celular , Imunidade Humoral , Aves Domésticas , Doenças das Aves Domésticas/patologia , Vacinação/veterinária , Vacinas Sintéticas
12.
Food Chem ; 343: 128518, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33160767

RESUMO

Here we present an innovative label-free immunochromatographic strip (ICTS) sensor, in which salt-induced aggregated gold nanoparticles (SIA-AuNPs) act as the signal probe, allowing in 14 min the identification and sensitive quantification of Salmonella as model targets. It has been evidenced that SIA-AuNPs could be absorbed on the surface of bacteria based on van der Waals forces. The SIA-AuNPs@Salmonella complex was captured by anti-Salmonella polyclonal antibody deposited on the test zone. With the label-free ICTS sensor, we successfully detected Salmonella in a concentration range of 103-108 CFU/mL and a visual detection limit of 1 × 103 CFU/mL. The band of test zone could be distinguished at a concentration of 103 CFU/mL by naked eye, which is 100-fold lower than the cationic AuNPs based method. The strip sensor was further validated with real samples including cabbage and drinking water with excellent precision and showed to provide excellent recovery.


Assuntos
Cromatografia de Afinidade/métodos , Microbiologia de Alimentos/métodos , Nanopartículas Metálicas/química , Salmonella , Anticorpos/imunologia , Brassica/microbiologia , Cromatografia de Afinidade/instrumentação , Contagem de Colônia Microbiana , Microbiologia de Alimentos/instrumentação , Ouro/química , Limite de Detecção , Salmonella/imunologia
13.
Front Immunol ; 11: 565142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33162979

RESUMO

Chagas disease caused by the protozoan parasite Trypanosoma cruzi is endemic in 21 Latin American countries and the southern United States and now is spreading into several other countries due to migration. Despite the efforts to control the vector throughout the Americas, currently, there are almost seven million infected people worldwide, causing ~10,000 deaths per year, and 70 million people at risk to acquire the infection. Chagas disease treatment is restricted only to two parasiticidal drugs, benznidazole and nifurtimox, which are effective during the acute and early infections but have not been found to be as effective in chronic infection. No prophylactic or therapeutic vaccine for human use has been communicated at this moment. Here, we evaluate in a mouse model a therapeutic DNA vaccine combining Cruzipain (Cz), a T. cruzi cysteine protease that proved to be protective in several settings, and Chagasin (Chg), which is the natural Cz inhibitor. The DNAs of both antigens, as well as a plasmid encoding GM-CSF as adjuvant, were orally administrated and delivered by an attenuated Salmonella strain to treat mice during the acute phase of T. cruzi infection. The bicomponent vaccine based on Salmonella carrying Cz and Chg (SChg+SCz) was able to improve the protection obtained by each antigen as monocomponent therapeutic vaccine and significantly increased the titers of antigen- and parasite-specific antibodies. More importantly, the bicomponent vaccine triggered a robust cellular response with interferon gamma (IFN-γ) secretion that rapidly reduced the parasitemia during the acute phase and decreased the tissue damage in the chronic stage of the infection, suggesting it could be an effective tool to ameliorate the pathology associated to Chagas disease.


Assuntos
Doença de Chagas/prevenção & controle , Cisteína Endopeptidases/imunologia , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia , Trypanosoma cruzi/imunologia , Vacinação/métodos , Vacinas de DNA/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Oral , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Doença de Chagas/parasitologia , Modelos Animais de Doenças , Feminino , Imunidade Celular , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Vacinas Protozoárias/administração & dosagem , Salmonella/imunologia , Resultado do Tratamento , Vacinas Atenuadas , Vacinas de DNA/administração & dosagem
14.
Vet Microbiol ; 250: 108867, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33010573

RESUMO

SalmonellaPathogenicity Island 19 (SPI-19) encoded type VI secretion system (T6SS) is a virulence factor present in few serotypes of S. enterica, including S. Dublin, S. Gallinarum and S. Pullorum. Comparative genomic sequence analysis revealed that the gene clusters of SPI-19 showed high homology to T6SS2 locus from avian pathogenic Escherichia coli, implying the similar T6SS locus is potentially related to the host adaption of both pathogens. Deletion of SPI-19 in S. Pullorum caused the dramatically decreased invasion into chicken LMH epithelial cells and HD-11 macrophages, and affected survival of Salmonella within both cells. In addition, deletion of SPI-19 caused the decreased colonization of S. Pullorum in chicken liver, spleen, ileum, and cecum at the initial infection stage, and induced rapid bacterial clearance. However, the SPI-19/T6SS had no effect on bacterial killing activity and induction of cytotoxicity to HD-11 macrophages. Further analysis demonstrated SPI-19/T6SS was involved in mediating the inhibition of host Th1 and Th2 immune responses, resulting in persistent colonization of S. Pullorum in hosts.


Assuntos
Interações entre Hospedeiro e Microrganismos , Macrófagos/microbiologia , Salmonella/imunologia , Salmonella/fisiologia , Sistemas de Secreção Tipo VI/genética , Animais , Linhagem Celular Tumoral , Galinhas , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Genômica , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/imunologia , Família Multigênica , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Sorogrupo , Células Th1/imunologia , Células Th2/imunologia , Sistemas de Secreção Tipo VI/metabolismo
15.
Sci Rep ; 10(1): 18439, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116156

RESUMO

The control of antibody specificity plays pivotal roles in key technological fields such as diagnostics and therapeutics. During the development of immunoassays (IAs) for the biosensing of pathogens in food matrices, we have found a way to rationalize and control the specificity of polyclonal antibodies (sera) for a complex analytical target (the Salmonella genus), in terms of number of analytes (Salmonella species) and potential cross-reactivity with similar analytes (other bacteria strains). Indeed, the biosensing of Salmonella required the development of sera and serum mixtures displaying homogeneous specificity for a large set of strains showing broad biochemical variety (54 Salmonella serovars tested in this study), which partially overlaps with the molecular features of other class of bacteria (like specific serogroups of E. coli). To achieve a trade-off between specificity harmonisation and maximization, we have developed a strategy based on the conversion of the specificity profiles of individual sera in to numerical descriptors, which allow predicting the capacity of serum mixtures to detect multiple bacteria strains. This approach does not imply laborious purification steps and results advantageous for process scaling-up, and may help in the customization of the specificity profiles of antibodies needed for diagnostic and therapeutic applications such as multi-analyte detection and recombinant antibody engineering, respectively.


Assuntos
Anticorpos Antibacterianos/imunologia , Especificidade de Anticorpos , Salmonella/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Escherichia coli/imunologia
16.
Recent Pat Biotechnol ; 14(4): 312-324, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32990553

RESUMO

BACKGROUND: Cholera triggered by Vibrio cholerae remains the main reason for morbidity and mortality all over the world. In addition, salmonellosis is regarded as an infectious disease that makes it essential for the identification and detection of Salmonella. With a beta-barrel structure consisting of eight non-parallel beta strands, OmpW family is widely distributed among gram-negative bacteria. Moreover, OmpW isolated from S. typhimurium and Vibrio cholerae can be used in vaccine design. METHODS: Topology prediction was determined. T-cell and B-cell epitopes were selected from exposed areas, and sequence conservancy was evaluated. The remaining loops and inaccessible residues were removed to prepare OmpW-1. High antigenicity peptides were detected to replace inappropriate residues to obtain OmpW-2. Physicochemical properties were assessed, and antigenicity, hydrophobicity, flexibility, and accessibility were compared to the native Omp-W structure. Low score areas were removed from the designed structure for preparing the OmpW-3. To construct OmpW-4, TTFrC was used as T-CD4+ cell-stimulating factor and CTB as adjuvant to the end of the C-terminal of this sequence, which can increase the antigenicity and sequence density. The sequences were re-analyzed to delete the unfavorable residues. Besides, the solubility of the mature OmpW and the designed structure were predicted while overexpressed in E. coli. RESULTS: The designed vaccine is a stable protein that has immune cells recognizing epitopes and is considered as an antigen. The construct can be overexpressed in an E. coli. CONCLUSION: The multi-epitope vaccine is a suitable stimulator for the immune system and would be a candidate for experimental research. Recent patents describe numerous inventions related to the clinical facets of vaccine peptide against human infectious disease.


Assuntos
Antígenos de Bactérias , Proteínas da Membrana Bacteriana Externa , Vacinas Bacterianas , Salmonella , Vibrio cholerae , Antígenos de Bactérias/química , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Cólera/microbiologia , Biologia Computacional , Simulação por Computador , Epitopos/química , Epitopos/imunologia , Humanos , Patentes como Assunto , Salmonella/química , Salmonella/imunologia , Infecções por Salmonella/microbiologia , Vacinas de Subunidades , Vibrio cholerae/química , Vibrio cholerae/imunologia
17.
PLoS One ; 15(9): e0238190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966297

RESUMO

Salmonella is an important human pathogen and poultry products constitute an important source of human infections. This study investigated prevalence; identified serotypes based on whole genome sequence, described spatial distribution of Salmonella serotypes and predicted risk factors that could influence the prevalence of Salmonella infection in commercial poultry farms in Nigeria. A cross sectional approach was employed to collect 558 pooled shoe socks and dust samples from 165 commercial poultry farms in North West Nigeria. On-farm visitation questionnaires were administered to obtain information on farm management practices in order to assess risk factors for Salmonella prevalence. Salmonella was identified by culture, biotyping, serology and polymerase chain reaction (PCR). PCR confirmed isolates were paired-end Illumina- sequenced. Following de novo genome assembly, draft genomes were used to obtain serotypes by SeqSero2 and SISTR pipeline and sequence types by SISTR and Enterobase. Risk factor analysis was performed using the logit model. A farm prevalence of 47.9% (CI95 [40.3-55.5]) for Salmonella was observed, with a sample level prevalence of 15.9% (CI95 [12.9-18.9]). Twenty-three different serotypes were identified, with S. Kentucky and S. Isangi as the most prevalent (32.9% and 11%). Serotypes showed some geographic variation. Salmonella detection was strongly associated with disposal of poultry waste and with presence of other livestock on the farm. Salmonella was commonly detected on commercial poultry farms in North West Nigeria and S. Kentucky was found to be ubiquitous in the farms.


Assuntos
Fazendas/estatística & dados numéricos , Aves Domésticas/microbiologia , Salmonella/isolamento & purificação , Animais , Nigéria , Prevalência , Fatores de Risco , Salmonella/classificação , Salmonella/imunologia , Sorogrupo
18.
Immunity ; 53(3): 533-547.e7, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32735843

RESUMO

Programmed cell death contributes to host defense against pathogens. To investigate the relative importance of pyroptosis, necroptosis, and apoptosis during Salmonella infection, we infected mice and macrophages deficient for diverse combinations of caspases-1, -11, -12, and -8 and receptor interacting serine/threonine kinase 3 (RIPK3). Loss of pyroptosis, caspase-8-driven apoptosis, or necroptosis had minor impact on Salmonella control. However, combined deficiency of these cell death pathways caused loss of bacterial control in mice and their macrophages, demonstrating that host defense can employ varying components of several cell death pathways to limit intracellular infections. This flexible use of distinct cell death pathways involved extensive cross-talk between initiators and effectors of pyroptosis and apoptosis, where initiator caspases-1 and -8 also functioned as executioners when all known effectors of cell death were absent. These findings uncover a highly coordinated and flexible cell death system with in-built fail-safe processes that protect the host from intracellular infections.


Assuntos
Apoptose/imunologia , Macrófagos/imunologia , Necroptose/imunologia , Piroptose/imunologia , Infecções por Salmonella/imunologia , Salmonella/imunologia , Animais , Caspase 1/deficiência , Caspase 1/genética , Caspase 12/deficiência , Caspase 12/genética , Caspase 8/genética , Caspases Iniciadoras/deficiência , Caspases Iniciadoras/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Proteína Serina-Treonina Quinases de Interação com Receptores/genética
19.
Infect Immun ; 88(10)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32601109

RESUMO

Salmonella causes grave systemic infections in humans and other animals and provides a paradigm for other diseases in which the bacteria have both intracellular and extracellular lifestyles. New generations of vaccines rely on the essential contribution of the antibody responses for their protection. The quality, antigen specificity, and functions associated with antibody responses to this pathogen have been elusive for a long time. Recent approaches that combine studies in humans and genetically manipulated experimental models and that exploit awareness of the location and within-host life cycle of the pathogen are shedding light on how humoral immunity to Salmonella operates. However, this area of research remains full of controversy and discrepancies. The overall scenario indicates that antibodies are essential for resistance against systemic Salmonella infections and can express the highest protective function when operating in conjunction with cell-mediated immunity. Antigen specificity, isotype profile, Fc-gamma receptor usage, and complement activation are all intertwined factors that still arcanely influence antibody-mediated protection to Salmonella.


Assuntos
Anticorpos Antibacterianos/imunologia , Infecções por Salmonella/imunologia , Salmonella/imunologia , Animais , Especificidade de Anticorpos/imunologia , Ativação do Complemento , Humanos , Imunidade Celular , Imunidade Humoral , Isotipos de Imunoglobulinas/imunologia , Receptores de IgG , Salmonella/crescimento & desenvolvimento , Salmonella/patogenicidade , Infecções por Salmonella/microbiologia
20.
BMC Microbiol ; 20(1): 197, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631309

RESUMO

BACKGROUND: Salmonella is one of the main causative agents of diarrhea which results in substantial disease burden. To determine the prevalence, serotype distribution, and antimicrobial resistance profiles of clinical Salmonella isolates in Shenzhen, a 6-year surveillance study was conducted. RESULTS: A total of 297 (5.7%) Salmonella strains were isolated from stool samples from 5239 patients. Among the 42 serotypes identified, serotype Typhimurium was the most common one which represented 39.7% of the isolates (118), followed by serotype Enteritidis (71, 23.9%), London (12, 4.0%), 4, 5, 12: i: - (11, 3.7%), and Senftenberg (8, 2.7%). A high frequency of resistance was found in ampicillin (70.6%), piperacillin (64.5%), tetracycline (63.5%), and streptomycin (54.3%). Resistance to ampicillin and tetracycline was observed in 95.3% of S. Typhimurium isolates; and nalidixic acid in 93.1% of S. Enteritidis isolates. Resistance to 5 or more antimicrobial agents was found in 78.8% of S. Typhimurium and 69.0% of S. Enteritidis isolates. A decreased susceptibility to ciprofloxacin and levofloxacin was associated with amino acid alteration in gyrA gene. Point mutations without amino acid changes were seen in gyrB, parC, and parE genes. CONCLUSIONS: A broad range of serotypes are responsible for Salmonellosis in Shenzhen, with Enteritidis and Typhimurium being the most common serotypes. The high level of antibiotic resistance is of public health significance and ongoing monitoring combined with rational use of antibiotics are recommended. Point mutations in gyrA gene might play an important role in the resistance to fluoroquinolones.


Assuntos
Antibacterianos/farmacologia , Diarreia/microbiologia , Farmacorresistência Bacteriana , Infecções por Salmonella/epidemiologia , Salmonella/classificação , Adolescente , Adulto , Criança , Pré-Escolar , China/epidemiologia , Diarreia/epidemiologia , Diarreia/imunologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Filogenia , Vigilância da População , Prevalência , Salmonella/efeitos dos fármacos , Salmonella/imunologia , Salmonella/isolamento & purificação , Infecções por Salmonella/imunologia , Sorogrupo , Adulto Jovem
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