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1.
Nat Commun ; 11(1): 543, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992714

RESUMO

Health care-associated infections such as Pseudomonas aeruginosa bacteremia pose a major clinical risk for hospitalized patients. However, these systemic infections are presumed to be a "dead-end" for P. aeruginosa and to have no impact on transmission. Here, we use a mouse infection model to show that P. aeruginosa can spread from the bloodstream to the gallbladder, where it replicates to extremely high numbers. Bacteria in the gallbladder can then seed the intestines and feces, leading to transmission to uninfected cage-mate mice. Our work shows that the gallbladder is crucial for spread of P. aeruginosa from the bloodstream to the feces during bacteremia, a process that promotes transmission in this experimental system. Further research is needed to test to what extent these findings are relevant to infections in patients.


Assuntos
Bacteriemia/microbiologia , Bacteriemia/transmissão , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/transmissão , Pseudomonas aeruginosa/patogenicidade , Animais , Bacteriemia/patologia , Modelos Animais de Doenças , Epitélio/microbiologia , Fezes/microbiologia , Feminino , Vesícula Biliar/microbiologia , Vesícula Biliar/patologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/patologia , Humanos , Intestinos/microbiologia , Intestinos/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pneumonia/microbiologia , Infecções por Pseudomonas/patologia , Sistemas de Secreção Tipo III
2.
PLoS One ; 15(1): e0227500, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923228

RESUMO

A new species of the Campylobacter genus is described, isolated from the preputial mucosa of bulls (Bos taurus). The five isolates obtained exhibit characteristics of Campylobacter, being Gram-negative non-motile straight rods, oxidase positive, catalase negative and microaerophilic. Phenotypic characteristics and nucleotide sequence analysis of 16S rRNA and hsp60 genes demonstrated that these isolates belong to a novel species within the genus Campylobacter. Based on hsp60 gene phylogenetic analysis, the most related species are C. ureolyticus, C. blaseri and C. corcagiensis. The whole genome sequence analysis of isolate FMV-PI01 revealed that the average nucleotide identity with other Campylobacter species was less than 75%, which is far below the cut-off for isolates of the same species. However, whole genome sequence analysis identified coding sequences highly homologous with other Campylobacter spp. These included several virulence factor coding genes related with host cell adhesion and invasion, transporters involved in resistance to antimicrobials, and a type IV secretion system (T4SS), containing virB2-virB11/virD4 genes, highly homologous to the C. fetus subsp. venerealis. The genomic G+C content of isolate FMV-PI01 was 28.3%, which is one of the lowest values reported for species of the genus Campylobacter. For this species the name Campylobacter portucalensis sp. nov. is proposed, with FMV-PI01 (= LMG 31504, = CCUG 73856) as the type strain.


Assuntos
Campylobacter/genética , Pênis/microbiologia , Animais , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Campylobacter/classificação , Campylobacter/isolamento & purificação , Campylobacter/metabolismo , Bovinos , Chaperonina 60/classificação , Chaperonina 60/genética , Chaperonina 60/metabolismo , Epitélio/microbiologia , Genótipo , Masculino , Fenótipo , Filogenia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Sequenciamento Completo do Genoma
3.
Arq Bras Cir Dig ; 32(4): e1480, 2019.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31859933

RESUMO

BACKGROUND: The presence of intestinal metaplasia in the distal esophagus (Barrett's esophagus) is an important precursor of adenocarcinoma. Knowledge of the risk factors and the process by which the Barrett develops is very important and Helicobacter pylori (HP) can contribute to this development. AIM: To analyze the impact of HP in the gastric mucosa with intestinal metaplasia in the distal esophagus in areas of columnar epithelialization smaller than 10 mm in length and epidemiological data on prevalence. METHOD: A retrospective study in which were included 373 consecutive patients diagnosed with columnar epithelium in the distal esophagus was done. In all, HP was investigated by urease and histology, exclusion and inclusion factors were applied and patients were divided into two groups: the first grouping the ones without histological diagnosis of Barrett's esophagus (235-63%) and the second with it (138-37%). RESULTS: There was no significant difference between HP and non-HP patients in relation to the probability of having intestinal metaplasia (p=0.587). When related to the general group, there was an inverse association between the bacterium and the columnar epithelia in the distal esophagus. Age (p=0.031), gender (p=0.013) and HP (p=0.613) when related together to intestinal metaplasia showed no significant relation. In isolation, when related to age and gender, regardless of HP, results confirmed that patients in more advanced age and women present a higher incidence of intestinal metaplasia. CONCLUSION: There is an inverse relation between HP and the areas of columnar epithelization in the distal esophagus, regardless of the presence or absence of intestinal metaplasia. Age and gender, regardless of HP, showed higher prevalence in women and in older the number of cases with intestinal metaplasia in the distal esophagus.


Assuntos
Esôfago de Barrett/patologia , Epitélio/patologia , Infecções por Helicobacter/patologia , Helicobacter pylori , Adulto , Fatores Etários , Idoso , Esôfago de Barrett/microbiologia , Epitélio/microbiologia , Feminino , Humanos , Masculino , Metaplasia/microbiologia , Metaplasia/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Sexuais
4.
J Fish Dis ; 42(10): 1433-1446, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31429104

RESUMO

Amoebic gill disease (AGD) is emerging as one of the most significant health challenges affecting farmed Atlantic salmon in the marine environment. It is caused by the amphizoic amoeba Neoparamoeba perurans, with infestation of gills causing severe hyperplastic lesions, compromising overall gill integrity and function. This study used histology, transmission electron microscopy (TEM), immunohistochemistry and transcript expression to relate AGD-associated pathological changes to changes in the morphology and distribution of chloride cells (CCs) in the gills of Atlantic salmon (Salmo salar L.) showing the progression of an AGD infection. A marked reduction in numbers of immunolabelled CCs was detected, and a changing pattern in distribution and morphology was closely linked with the level of basal epithelial hyperplasia in the gill. In addition, acute degenerative ultrastructural changes to CCs at the lesion site were observed with TEM. These findings were supported by the early-onset downregulation of Na+ /K+ -ATPase transcript expression. This study provides supportive evidence that histological AGD lesion assessment was a good qualitative tool for AGD scoring and corresponded well with qPCR genomic Paramoeba perurans quantification. Ultrastructural changes induced in salmon CCs as a result of AGD are reported here for the first time.


Assuntos
Amebíase/veterinária , Doenças dos Peixes/patologia , Brânquias/patologia , Salmo salar , Amebíase/patologia , Animais , Epitélio/microbiologia , Epitélio/patologia , Epitélio/ultraestrutura , Expressão Gênica/fisiologia , Brânquias/citologia , Brânquias/microbiologia , Brânquias/ultraestrutura , Imuno-Histoquímica/veterinária , Microscopia Eletrônica de Transmissão/veterinária
5.
Nat Commun ; 10(1): 3224, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324782

RESUMO

Proteolytic homeostasis is important at mucosal surfaces, but its actors and their precise role in physiology are poorly understood. Here we report that healthy human and mouse colon epithelia are a major source of active thrombin. We show that mucosal thrombin is directly regulated by the presence of commensal microbiota. Specific inhibition of luminal thrombin activity causes macroscopic and microscopic damage as well as transcriptomic alterations of genes involved in host-microbiota interactions. Further, luminal thrombin inhibition impairs the spatial segregation of microbiota biofilms, allowing bacteria to invade the mucus layer and to translocate across the epithelium. Thrombin cleaves the biofilm matrix of reconstituted mucosa-associated human microbiota. Our results indicate that thrombin constrains biofilms at the intestinal mucosa. Further work is needed to test whether thrombin plays similar roles in other mucosal surfaces, given that lung, bladder and skin epithelia also express thrombin.


Assuntos
Bactérias/metabolismo , Biofilmes , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/microbiologia , Trombina/metabolismo , Animais , Linhagem Celular , Colo/microbiologia , Neoplasias do Colo/microbiologia , Epitélio/microbiologia , Homeostase , Humanos , Pulmão , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Pele , Trombina/genética , Bexiga Urinária
6.
Microbiome ; 7(1): 83, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159860

RESUMO

BACKGROUND: The development of the rumen is an important physiological challenge for young ruminants. Previous studies have shown that starter feeding can effectively facilitate the growth and development of the rumen in ruminants. However, the mechanism through which starter feeding stimulates the development of the rumen is not clear. Here, we performed an integrated analysis in ruminal microbiota and a host transcriptomic profile in a lamb model with the intervention of starter feed to understand the ruminal microbiome-host crosstalk in stimulating the development of the ruminal epithelium. RESULTS: Decreased ruminal pH and increased acetate and butyrate concentrations in the rumen, followed by increasing rumen organ index, were observed in lambs supplemented with starter. Using metagenome sequencing in combination with 16S rRNA and 18S rRNA gene amplicon sequencing, the results showed the abundance of acetate-producing Mitsuokella spp., lactate-producing Sharpea spp., lactate-utilizing Megasphaera spp., and Entodinium spp. was enriched in rumen microbial communities in the starter-feed group. The abundances of genes involved in sugar degradation were decreased in starter-feed lambs, but the GH13 encoding α-amylase was obviously increased. Rumen epithelial transcriptome analysis revealed that seven differentially expressed genes, including MAPK1, PIK3CB, TNFSF10, ITGA6, SNAI2, SAV1, and DLG, related to the cell growth module were upregulated, and BAD's promotion of cell death was downregulated. Correlation analysis revealed that the increase in the concentrations of acetate and butyrate significantly correlated with the expression of these genes, which indicates acetate and butyrate likely acted as important drivers in the ruminal microbiome-host crosstalk. CONCLUSIONS: The present study comprehensively describes the symbiotic relationship between the rumen microbiota and the host in lambs after starter feeding. Our data demonstrates that the microbiome-driven generation of acetate and butyrate mediated the growth-related genes' regulation of the growth-associated signalling pathway in the ruminal epithelium. These co-development networks regulated many physiological processes in the epithelium, including papillae morphology and rumen epithelial growth.


Assuntos
Epitélio/fisiologia , Interações entre Hospedeiro e Microrganismos , Microbiota , Rúmen/microbiologia , Transdução de Sinais , Acetatos/metabolismo , Ração Animal , Animais , Bactérias/classificação , Bactérias/metabolismo , Butiratos/metabolismo , Epitélio/microbiologia , Concentração de Íons de Hidrogênio , Metagenoma , RNA Ribossômico 16S/genética , Rúmen/fisiologia , Ovinos/crescimento & desenvolvimento , Ovinos/microbiologia , Transcriptoma
7.
Artigo em Inglês | MEDLINE | ID: mdl-31214514

RESUMO

Epithelial tissues protecting organs from the environment are the first-line of defense against pathogens. Therefore, efficient repair mechanisms after injury are crucial to maintain epithelial integrity. However, these healing processes can be insufficient to restore epithelial integrity, notably in infectious conditions. Pseudomonas aeruginosa infections in cutaneous, corneal, and respiratory tract epithelia are of particular concern because they are the leading causes of hospitalizations, disabilities, and deaths worldwide. Pseudomonas aeruginosa has been shown to alter repair processes, leading to chronic wounds and infections. Because of the current increase in the incidence of multi-drug resistant isolates of P. aeruginosa, complementary approaches to decrease the negative impact of these bacteria on epithelia are urgently needed. Here, we review the recent advances in the understanding of the impact of P. aeruginosa infections on the integrity and repair mechanisms of alveolar, airway, cutaneous and corneal epithelia. Potential therapeutic avenues aimed at counteracting this deleterious impact of infection are also discussed.


Assuntos
Epitélio/microbiologia , Epitélio/fisiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/fisiologia , Células Epiteliais Alveolares , Animais , Farmacorresistência Bacteriana Múltipla , Epitélio/lesões , Epitélio Anterior , Humanos , Incidência , Infecções por Pseudomonas/terapia , Pseudomonas aeruginosa/isolamento & purificação , Mucosa Respiratória
8.
J Dairy Sci ; 102(8): 6738-6749, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31178178

RESUMO

Microbiome modulators such as probiotics are known to modulate oral diseases. Very few probiotics are commercially available for use in the oral cavity. In this context, we selected human-origin Lactobacillus salivarius AR809 as a promising oropharyngeal probiotic and characterized its functional and immunomodulatory properties. Results demonstrated that AR809 could efficiently adhere to pharyngeal epithelial FaDu cells, antagonize Staphylococcus aureus, adapt to the oral environment, and modulate host innate immunity by inducing potentially protective effects. Particularly, AR809 diminished proinflammatory activity by enhancing the production of IL10 and inhibiting the expression of tumor necrosis factor-α, IL1B, inducible nitric oxide synthase, and RELA. Finally, we observed that AR809 grew efficiently when cultured in milk, suggesting that the preparation of a fermented milk product containing AR809 could be a practical way to administer this probiotic to humans. In conclusion, AR809 has high potential to adhere to the pharyngeal mucosa and could be applied in novel milk-based probiotic fermented food products.


Assuntos
Aderência Bacteriana/fisiologia , Imunidade/fisiologia , Lactobacillus salivarius/isolamento & purificação , Lactobacillus salivarius/fisiologia , Boca/microbiologia , Faringe/microbiologia , Animais , Produtos Fermentados do Leite , Epitélio/microbiologia , Humanos , Inflamação/prevenção & controle , Probióticos , Fator de Necrose Tumoral alfa/antagonistas & inibidores
9.
J Clin Invest ; 129(5): 2107-2122, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30985294

RESUMO

Alveolar epithelium plays a pivotal role in protecting the lungs from inhaled infectious agents. Therefore, the regenerative capacity of the alveolar epithelium is critical for recovery from these insults in order to rebuild the epithelial barrier and restore pulmonary functions. Here, we show that sublethal infection of mice with Streptococcus pneumoniae, the most common pathogen of community-acquired pneumonia, led to exclusive damage in lung alveoli, followed by alveolar epithelial regeneration and resolution of lung inflammation. We show that surfactant protein C-expressing (SPC-expressing) alveolar epithelial type II cells (AECIIs) underwent proliferation and differentiation after infection, which contributed to the newly formed alveolar epithelium. This increase in AECII activities was correlated with increased nuclear expression of Yap and Taz, the mediators of the Hippo pathway. Mice that lacked Yap/Taz in AECIIs exhibited prolonged inflammatory responses in the lung and were delayed in alveolar epithelial regeneration during bacterial pneumonia. This impaired alveolar epithelial regeneration was paralleled by a failure to upregulate IκBa, the molecule that terminates NF-κB-mediated inflammatory responses. These results demonstrate that signals governing resolution of lung inflammation were altered in Yap/Taz mutant mice, which prevented the development of a proper regenerative niche, delaying repair and regeneration of alveolar epithelium during bacterial pneumonia.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células Epiteliais Alveolares/citologia , Proteínas de Ciclo Celular/metabolismo , Pneumonia Pneumocócica/patologia , Proteína C Associada a Surfactante Pulmonar/metabolismo , Transativadores/metabolismo , Animais , Diferenciação Celular , Núcleo Celular/metabolismo , Proliferação de Células , Células Epiteliais/metabolismo , Epitélio/microbiologia , Células HEK293 , Humanos , Inflamação/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/metabolismo , Regeneração , Transdução de Sinais , Células-Tronco/citologia , Streptococcus pneumoniae
10.
J Dairy Sci ; 102(6): 5361-5378, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31005320

RESUMO

The feeding of high-grain diets to dairy cows commonly results in lowered pH and ruminal dysbiosis, characterized by changes in absorption dynamics of short-chain fatty acids (SCFA) across the reticuloruminal wall, epithelial function, and the epithelial bacteria community structure. Therefore, the present study evaluated the effect of high-grain feeding persistence on the absorption kinetics of reticuloruminal SCFA, gene expression in the rumen epithelium, and the associated shifts in the epithelial bacteria in cows recovering from either a long-term continuous high-grain feeding model or a long-term transient high-grain feeding model. In a crossover study design, 8 nonlactating Holstein cows were fed 60% concentrate either continuously for 4 wk (continuous) or with a 1-wk break in the second week of the high-grain feeding (transient). After the high-grain feeding, all animals were fed a diet of 100% forage (recovery) for an additional 8 wk. Rumen papilla biopsies and SCFA absorption measurements were taken at the start of the trial (baseline), after the 4-wk high-grain feeding (49 d), after 2-wk recovery forage feeding (63 d), and after 8-wk recovery forage (105 d). Absorption of SCFA was determined in vivo using the washed and isolated reticulorumen technique. Rumen papillae biopsies were used for adherent bacterial DNA and host RNA extraction. The epithelial bacteria were determined using Illumina MiSeq (Microsynth AG, Balgach, Switzerland) sequencing of the 16S rRNA gene. No significant effects of the high-grain feeding model were seen for bacterial diversity. However, bacterial diversity increased with time spent in the recovery forage feeding period regardless of feeding model. The relative abundance of Acidobacteria phyla and Acetivibrio spp. increased when animals were fed a transient high-grain feeding model. A trend toward increased CLDN4 expression was observed in the continuous model. Furthermore, there were interactions between feeding model and sampling day for gene targets CD14, DRA, NHE2, NHE3, and MCT2. When comparing length of recovery, in the continuous model increased relative absorption of SCFA was sustained at 63 d but dropped to baseline measurements at 105 d. A similar pattern was found with the transient model but it did not reach significance. The only gene target that was found to significantly correlate to relative absorption of SCFA was DRA (correlation coefficient ≤ -0.41). Whereas, genera Alkalibaculum, Anaerorhabdus, Coprococcus, and Dethiobacter all showed positive correlations to gene targets for pH regulation (NHE2 and NHE3) and SCFA uptake (MCT1) but negative correlations to SCFA absorption. We conclude that while the rumen absorption and epithelial bacteria were able to recover to baseline levels after 8 wk of forage feeding, the time needed for re-establishment of homeostasis in host gene expression is longer, especially when high-grain feeding is interrupted.


Assuntos
Ração Animal/análise , Bactérias/metabolismo , Bovinos/fisiologia , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal , Animais , Bovinos/microbiologia , Estudos Cross-Over , Dieta/veterinária , Grão Comestível , Epitélio/microbiologia , Feminino , Expressão Gênica , Rúmen/metabolismo
11.
Nat Commun ; 10(1): 1194, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30886143

RESUMO

Chronic infections of the fallopian tubes with Chlamydia trachomatis (Ctr) cause scarring and can lead to infertility. Here we use human fallopian tube organoids and genital Ctr serovars D, K and E for long-term in vitro analysis. The epithelial monolayer responds with active expulsion of the bacteria into the lumen and with compensatory cellular proliferation-demonstrating a role of epithelial homeostasis in the defense against this pathogen. In addition, Ctr infection activates LIF signaling, which we find to be an essential regulator of stemness in the organoids. Infected organoids exhibit a less differentiated phenotype with higher stemness potential, as confirmed by increased organoid forming efficiency. Moreover, Ctr increases hypermethylation of DNA, which is an indicator of accelerated molecular aging. Thus, the chronic organoid infection model suggests that Ctr has a long-term impact on the epithelium. These heritable changes might be a contributing factor in the development of tubal pathologies, including the initiation of high grade serous ovarian cancer.


Assuntos
Infecções por Chlamydia/genética , Chlamydia trachomatis/imunologia , Ilhas de CpG/genética , Metilação de DNA/imunologia , Interações entre Hospedeiro e Microrganismos/genética , Células-Tronco/metabolismo , Fatores Etários , Infecções por Chlamydia/imunologia , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/genética , Doença Crônica , Ilhas de CpG/imunologia , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/imunologia , Cistadenocarcinoma Seroso/microbiologia , Epigênese Genética/genética , Epigênese Genética/imunologia , Epitélio/imunologia , Epitélio/metabolismo , Epitélio/microbiologia , Tubas Uterinas/imunologia , Tubas Uterinas/metabolismo , Tubas Uterinas/microbiologia , Feminino , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Microscopia Intravital , Microscopia Confocal , Organoides/imunologia , Organoides/metabolismo , Organoides/microbiologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/microbiologia , Sorogrupo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Análise de Célula Única , Células-Tronco/imunologia , Células-Tronco/microbiologia , Técnicas de Cultura de Tecidos
12.
Artigo em Inglês | MEDLINE | ID: mdl-30670411

RESUMO

Nacubactam is a novel, broad-spectrum, ß-lactamase inhibitor that is currently under development as combination therapy with meropenem. This study evaluated the efficacy of human-simulated epithelial lining fluid (ELF) exposures of meropenem, nacubactam, and the combination of meropenem and nacubactam against class A serine carbapenemase-producing Enterobacteriaceae isolates in the neutropenic murine lung infection model. Twelve clinical meropenem-resistant Klebsiella pneumoniae, Escherichia coli, and Enterobacter cloacae isolates, all harboring KPC or IMI-type ß-lactamases, were utilized in the study. Meropenem, nacubactam, and meropenem-nacubactam (1:1) combination MICs were determined in triplicate via broth microdilution. At 2 h after intranasal inoculation, neutropenic mice were dosed with regimens that provided ELF profiles mimicking those observed in humans given meropenem at 2 g every 8 h and/or nacubactam at 2 g every 8 h (1.5-h infusions), alone or in combination. Efficacy was assessed as the change in bacterial growth at 24 h, compared with 0-h controls. Meropenem, nacubactam, and meropenem-nacubactam MICs were 8 to >64 µg/ml, 2 to >256 µg/ml, and 0.5 to 4 µg/ml, respectively. The average bacterial density at 0 h across all isolates was 6.31 ± 0.26 log10 CFU/lung. Relative to the 0-h control, the mean values of bacterial growth at 24 h in the untreated control, meropenem human-simulated regimen treatment, and nacubactam human-simulated regimen treatment groups were 2.91 ± 0.27, 2.68 ± 0.42, and 1.73 ± 0.75 log10 CFU/lung, respectively. The meropenem-nacubactam combination human-simulated regimen resulted in reductions of -1.50 ± 0.59 log10 CFU/lung. Meropenem-nacubactam human-simulated ELF exposure produced enhanced efficacy against all class A serine carbapenemase-producing Enterobacteriaceae isolates tested in the neutropenic murine lung infection model.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Epitélio/efeitos dos fármacos , Meropeném/farmacologia , Serina/metabolismo , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismo , Animais , Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/metabolismo , Infecções por Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Epitélio/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana
13.
PLoS Comput Biol ; 15(1): e1006646, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30673699

RESUMO

Infections of stratified epithelia contribute to a large group of common diseases, such as dermatological conditions and sexually transmitted diseases. To investigate how epithelial structure affects infection dynamics, we develop a general ecology-inspired model for stratified epithelia. Our model allows us to simulate infections, explore new hypotheses and estimate parameters that are difficult to measure with tissue cell cultures. We focus on two contrasting pathogens: Chlamydia trachomatis and Human papillomaviruses (HPV). Using cervicovaginal parameter estimates, we find that key infection symptoms can be explained by differential interactions with the layers, while clearance and pathogen burden appear to be bottom-up processes. Cell protective responses to infections (e.g. mucus trapping) generally lowered pathogen load but there were specific effects based on infection strategies. Our modeling approach opens new perspectives for 3D tissue culture experimental systems of infections and, more generally, for developing and testing hypotheses related to infections of stratified epithelia.


Assuntos
Epitélio/imunologia , Epitélio/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Modelos Biológicos , Técnicas de Cultura de Células , Infecções por Chlamydia/imunologia , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/imunologia , Chlamydia trachomatis/patogenicidade , Epitélio/microbiologia , Epitélio/virologia , Feminino , Humanos , Papillomaviridae/imunologia , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Vagina/citologia , Vagina/imunologia
14.
Infect Immun ; 87(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30692180

RESUMO

Studies have implicated Gardnerella vaginalis as an important etiological agent in bacterial vaginosis (BV). It produces a cholesterol-dependent cytolysin, vaginolysin (VLY). In this study, we sought to characterize the interaction between vaginal epithelium, G. vaginalis, and VLY using EpiVaginal tissues from MatTek. These tissues are three-dimensional and have distinct apical and basolateral sides, enabling comparison of the effects of G. vaginalis and VLY following exposure to either side. We measured cytotoxicity, cytokine production, and bacterial growth, following apical versus basolateral exposure. G. vaginalis exhibited more-rapid growth in coculture with the tissue model when it was exposed to the apical side. VLY permeabilized cells on the basolateral side of the tissues but failed to permeabilize apical epithelial cells. Cytokine secretion in response to VLY and G. vaginalis also depended on the polarity of exposure. VLY did not cause significant changes in cytokine levels when exposed apically. Apical tissue challenge by G. vaginalis appeared to dampen the inflammatory response, as decreases in granulocyte-macrophage colony-stimulating factor (GM-CSF) (6.6-fold), RANTES (14.8-fold), and interferon gamma inducible protein 10 kDa (IP-10) (53-fold) and an increase in interleukin-1 receptor antagonist (IL-1ra) (5-fold) were observed. In vivo, G. vaginalis normally colonizes the apical face of the vaginal epithelium. Results from this study suggest that while G. vaginalis may grow on the apical face of the vaginal epithelium, its VLY toxin does not target these cells in this model. This phenomenon could have important implications regarding colonization of the vagina by G. vaginalis and may suggest an explanation for the lack of an overt immune response to this organism.


Assuntos
Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Epitélio/microbiologia , Gardnerella vaginalis/metabolismo , Vagina/microbiologia , Vaginose Bacteriana/microbiologia , Feminino , Gardnerella vaginalis/genética , Gardnerella vaginalis/crescimento & desenvolvimento , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Interleucina-18/genética , Interleucina-18/metabolismo , Vagina/patologia , Vaginose Bacteriana/genética , Vaginose Bacteriana/metabolismo , Vaginose Bacteriana/patologia
15.
J Dairy Sci ; 102(2): 1866-1882, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30580938

RESUMO

The stratified squamous ruminal epithelium is the main site for absorption of key nutrients (e.g., short-chain fatty acids; SCFA) and electrolytes (e.g., sodium and magnesium). The absorptive function has to be highly selective to prevent simultaneous entry of microbes and toxins from the rumen into the blood. As such, epithelial absorption is primarily transcellular, whereas the paracellular pathway appears rather tightly sealed. A network of tight junction (claudin-1, claudin-4, and occludin) and tight junction-associated proteins (e.g., zonula occludens) accomplishes the latter. When microbial fermentation activity is high such as with highly fermentable diets, rumen epithelial functions are often challenged by acidity, high osmolarity, toxins (e.g., endotoxin and histamine), and immune mediators (inflammatory mediators and cytokines) released during local and systemic inflammation. Epithelial damage by low pH in combination with high luminal SCFA concentrations is not immediately reversible and may initially aggravate upon return to physiological pH. In contrast, barrier opening upon hyperosmolarity is acutely transient. The initial insults set by luminal acidity and SCFA and the increasing concentrations of microbial-associated molecular patterns such as lipopolysaccharides are key factors that trigger inflammation not only in the rumen but also in the hindgut (cecum and colon), which reach out to the liver and other organs, causing systemic inflammation. Low feed intake during parturition, transportation, heat stress, or disease is the second most relevant challenge for the ruminal epithelial barrier. The barrier opening is usually only transient and quickly restored upon refeeding. Due to a rapid, dose-dependent, and prolonged decrease in absorption capacity for SCFA, however, any feed restriction increases the odds for postrestriction subacute ruminal acidosis. Inflammation due to acidosis can be alleviated by supplemental thiamine, yeasts, and plant bioactive (phytogenic) compounds. Butyrate is used in weaning calves to support ruminal barrier development; however, excess butyrate may promote hyperkeratosis, parakeratosis, and epithelial injury in the fully developed rumen of adult cows. Further research is needed to enhance the understanding of the various factors that counteract barrier impairment and help barrier restoration during acidogenic feeding, especially when concurring with unavoidable periods of feed restriction.


Assuntos
Bovinos/metabolismo , Epitélio/metabolismo , Rúmen/metabolismo , Animais , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Bovinos/microbiologia , Dieta/veterinária , Epitélio/microbiologia , Ácidos Graxos Voláteis/metabolismo , Feminino , Rúmen/microbiologia
16.
J Agric Food Chem ; 67(1): 551-561, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30520636

RESUMO

A high-grain (HG) diet can result in ruminal subacute acidosis, which is detrimental to gut health and can lead to decreased productivity. This study investigated the ileal epithelial microbiota and its relationship with host epithelial function in goats fed a HG diet (concentrate/hay, 90:10) and a control diet (concentrate/hay, 55:45), aiming to elucidate the mechanisms involved in ileal adaptation to subacute acidosis. The HG challenge increased the ileal volatile fatty acid concentration ( p = 0.030) and altered the ileal epithelial microbiota by increasing (FDR < 0.05) relative abundances of active carbohydrate and protein degraders Synergistetes, Prevotella, Fibrobacter, Clostridium, Treponema, and unclassified Ruminococcaceae by 20.1-, 6.3-, 16.8-, 8.5-, 19.9-, and 7.1-fold, respectively. However, the HG diet tended to reduce (FDR < 0.10) the relative abundance of Candidatus Arthromitus (38.8 ± 36.1 versus 2.1 ± 3.1). Microbial functional potentials inferred using PICRUSt indicated that the HG challenge elevated abundances of pathways associated with metabolism of amino acid, glycan, cofactors, and vitamins, whereras it decreased pathways associated with signal transduction, xenobiotic biodegradation, and metabolism. Additionally, in the ileal epithelium of HG goats, transcriptome analysis identified the increment (FDR < 0.10) of candidate genes involved in metabolism of carbohydrates, lipids, proteins, vitamins, and the proinflammatory cytokine pathway, while downregulating genes encoding antimicrobials and complements (FDR < 0.05). Collectively, the HG challenge shifted the structure and functional potentials of the ileal microbial community and affected the host responses in the ileum of goats toward increased metabolic activities of macro- and micronutrients, together with an increased risk of gut inflammation.


Assuntos
Bactérias/isolamento & purificação , Microbioma Gastrointestinal , Cabras/genética , Cabras/microbiologia , Íleo/microbiologia , Ração Animal/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Citocinas/genética , Citocinas/metabolismo , Grão Comestível/química , Grão Comestível/metabolismo , Epitélio/metabolismo , Epitélio/microbiologia , Cabras/metabolismo , Homeostase , Íleo/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Proteínas/genética , Proteínas/metabolismo , Transcriptoma
17.
PLoS One ; 13(12): e0209341, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30576365

RESUMO

Bacillus aquimaris SH6 spores produce carotenoids that are beneficial to white-leg shrimp (Litopenaeus vannamei) health. However, the optimal dose and mechanisms behind these effects are not well understood. We investigated the fate of SH6 spores in the gut of L. vannamei. Shrimp were divided into six groups administrated with either feed only (negative control) or SH6 spores at 5 × 106 CFU/g pellet (high dose, SH6 spore-H group), 1 × 106 CFU/g pellet (medium dose, SH6 spore-M group), 2 × 105 CFU/g pellet (low dose, SH6 spore-L group), astaxanthin at 0.5 mg/g pellet (Carophyll group), or carotenoids from SH6 vegetative cells at 5 µg/g pellet (SH6 carotenoid group). The growth rate was highest in SH6 spore-H (3.38%/day), followed by SH6 spore-M (2.84%/day) and SH6 spore-L (2.25%/day), which was significantly higher than the control (1.45%/day), Carophyll (1.53%/day) or SH6 carotenoid (1.57%/day) groups. The astaxanthin levels (1.9-2.0 µg/g shrimp) and red-colour scores (21-22) in SH6 spore-H/M were higher than the control (astaxanthin: 1.2 µg/g shrimp; red score: 20) or SH6 spore-L, but lower than the Carophyll and SH6 carotenoids. Feeding with medium and high doses of SH6 spores after 28 days resulted in respective 1.3-2-fold increases in phenol oxidase activity and 8-9 fold increases in Rho mRNA expression compared to the control and low dose group. The live-counts of SH6 in the gut gradually increased during the 28-day feeding period with SH6 spores at different concentrations, starting from 4.1, 8.2, and 5.4 × 104 CFU/g gut at day 1 and reaching 5.3, 5.1, and 4.4 × 105 CFU/g gut in the SH6-H/M/L groups, respectively, at day 28. Gut microbiota became more diversified, resulting in a 2-8-fold increase in total bacterial live-counts compared to the controls. SH6 spore germination was detected by measuring the mRNA expression of a specific sequence coding for SH6 amylase at 4 h, reaching saturation at 24 h. Our results confirm that SH6 spores colonize and germinate in the gut to improve the microbial diversity and boost the immune system of shrimp, exhibiting beneficial effects at >1 × 106 CFU/g pellet.


Assuntos
Carotenoides/administração & dosagem , Microbioma Gastrointestinal/fisiologia , Penaeidae/microbiologia , Probióticos/administração & dosagem , Esporos Bacterianos/metabolismo , Ração Animal/microbiologia , Animais , Aquicultura/métodos , Bacillus/fisiologia , Carotenoides/imunologia , Carotenoides/metabolismo , Cor , Epitélio/microbiologia , Epitélio/fisiologia , Penaeidae/fisiologia , Frutos do Mar , Esporos Bacterianos/imunologia , Vírus da Síndrome da Mancha Branca 1
18.
Front Immunol ; 9: 2710, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30524442

RESUMO

Neisseria gonorrhoeae is an obligate human pathogen that causes mucosal surface infections of male and female reproductive tracts, pharynx, rectum, and conjunctiva. Asymptomatic or unnoticed infections in the lower reproductive tract of women can lead to serious, long-term consequences if these infections ascend into the fallopian tube. The damage caused by gonococcal infection and the subsequent inflammatory response produce the condition known as pelvic inflammatory disease (PID). Infection can lead to tubal scarring, occlusion of the oviduct, and loss of critical ciliated cells. Consequences of the damage sustained on the fallopian tube epithelium include increased risk of ectopic pregnancy and tubal-factor infertility. Additionally, the resolution of infection can produce new adhesions between internal tissues, which can tear and reform, producing chronic pelvic pain. As a bacterium adapted to life in a human host, the gonococcus presents a challenge to the development of model systems for probing host-microbe interactions. Advances in small-animal models have yielded previously unattainable data on systemic immune responses, but the specificity of N. gonorrhoeae for many known (and unknown) host targets remains a constant hurdle. Infections of human volunteers are possible, though they present ethical and logistical challenges, and are necessarily limited to males due to the risk of severe complications in women. It is routine, however, that normal, healthy fallopian tubes are removed in the course of different gynecological surgeries (namely hysterectomy), making the very tissue most consequentially damaged during ascending gonococcal infection available for laboratory research. The study of fallopian tube organ cultures has allowed the opportunity to observe gonococcal biology and immune responses in a complex, multi-layered tissue from a natural host. Forty-five years since the first published example of human fallopian tube being infected ex vivo with N. gonorrhoeae, we review what modeling infections in human tissue explants has taught us about the gonococcus, what we have learned about the defenses mounted by the human host in the upper female reproductive tract, what other fields have taught us about ciliated and non-ciliated cell development, and ultimately offer suggestions regarding the next generation of model systems to help expand our ability to study gonococcal pathogenesis.


Assuntos
Tubas Uterinas , Gonorreia , Modelos Imunológicos , Neisseria gonorrhoeae/imunologia , Doença Inflamatória Pélvica , Animais , Epitélio/imunologia , Epitélio/microbiologia , Epitélio/patologia , Tubas Uterinas/imunologia , Tubas Uterinas/microbiologia , Tubas Uterinas/patologia , Feminino , Gonorreia/imunologia , Gonorreia/patologia , Humanos , Técnicas de Cultura de Órgãos , Doença Inflamatória Pélvica/imunologia , Doença Inflamatória Pélvica/microbiologia , Doença Inflamatória Pélvica/patologia , Gravidez , Gravidez Ectópica/imunologia , Gravidez Ectópica/microbiologia , Gravidez Ectópica/patologia
19.
Nat Immunol ; 19(12): 1286-1298, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30446754

RESUMO

The skin provides both a physical barrier and an immunologic barrier to external threats. The protective machinery of the skin has evolved to provide situation-specific responses to eliminate pathogens and to provide protection against physical dangers. Dysregulation of this machinery can give rise to the initiation and propagation of inflammatory loops in the epithelial microenvironment that result in inflammatory skin diseases in susceptible people. A defective barrier and microbial dysbiosis drive an interleukin 4 (IL-4) loop that underlies atopic dermatitis, while in psoriasis, disordered keratinocyte signaling and predisposition to type 17 responses drive a pathogenic IL-17 loop. Here we discuss the pathogenesis of atopic dermatitis and psoriasis in terms of the epithelial immune microenvironment-the microbiota, keratinocytes and sensory nerves-and the resulting inflammatory loops.


Assuntos
Dermatite Atópica/imunologia , Psoríase/imunologia , Pele/imunologia , Animais , Dermatite Atópica/microbiologia , Dermatite Atópica/fisiopatologia , Disbiose/imunologia , Disbiose/microbiologia , Disbiose/fisiopatologia , Epitélio/imunologia , Epitélio/microbiologia , Epitélio/fisiopatologia , Humanos , Psoríase/microbiologia , Psoríase/fisiopatologia , Pele/microbiologia
20.
J Anim Sci ; 96(10): 4293-4305, 2018 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-30272228

RESUMO

The objective of this study was to evaluate the changes in the ruminal fermentation, epithelium-associated microbiota, and ruminal epithelial barrier function in response to severe feed restriction (SFR) in pregnant ewes. Sixteen pregnant ewes (108 d of gestation) were randomly blocked and assigned to 1 of 2 treatments: control (CON, n = 8) and SFR (n = 8). Ewes were fed a common diet with a 60:40 forage to concentrate ratio for 7-d baseline period followed by a SFR challenge period. Ewes on the SFR treatment were restricted to 30% of the base for 15 d. At the end of the experimental period, all animals were slaughtered and then ruminal contents and ruminal epithelial tissue were collected. Results showed that ruminal pH was greater in SFR group (P = 0.040) compared with CON group, while SFR decreased (P < 0.05) the concentrations of ruminal acetate, propionate, butyrate, and total volatile fatty acid. A plot of principal coordinate analysis and analysis of molecular variance revealed that the composition of ruminal epithelial bacterial communities in the CON group was distinct from that of the ruminal epithelial microbiome in the SFR animals. At the genus level, SFR increased the abundance of unclassified Neisseriaceae, Comamonas, and Papillibacter, and decreased the proportion of Howardella, Desulfobulbus, and Suttonella (P < 0.05) compared with CON group. The metagenome of ruminal epithelium-associated microbiota predicted by PICRUSt revealed that the SFR significantly affected 14 metabolic pathways, and 9 were significantly enriched in the SFR group. In particular, SFR markedly increased relative abundances of dominant gene families involved in amino acid metabolism (P = 0.003), cellular processes and signaling (P = 0.021), and lipid metabolism (P = 0.001). The real-time PCR results showed SFR decreased the mRNA expression of IL-10 (P = 0.003) and upregulated the mRNA expression of IL-6 (P = 0.003) and TLR4 (P = 0.021). The mRNA expression of Claudin-1 (P = 0.001) and ZO-1 (P = 0.009) were lower in the SFR group compared with the CON group. Generally, our data suggest that SFR decreased most ruminal fermentation parameters, altered the composition of rumen epithelium-associated microbiota, and compromised the barrier function of rumen epithelium. These findings are of great importance for understanding the alteration in the rumen function following SFR in pregnant ewes.


Assuntos
Ração Animal/análise , Privação de Alimentos , Microbiota , Ovinos/fisiologia , Animais , Butiratos/análise , Dieta/veterinária , Epitélio/microbiologia , Epitélio/fisiologia , Ácidos Graxos Voláteis/análise , Feminino , Fermentação , Gravidez , Propionatos/análise , Distribuição Aleatória , Rúmen/microbiologia , Rúmen/fisiologia , Ovinos/microbiologia
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