RESUMO
To prevent the progression of type 2 diabetes mellitus (T2DM), early detection and intervention are important. Several studies have already shown that the serum adiponectin level could be useful for evaluating the future risk of T2DM. Recently, plasma free amino acid (PFAA) concentrations have also emerged as potential biomarkers that predict the future onset of T2DM. In this study, we aimed to further characterise PFAA profiles by elucidating the association with the serum high molecular weight (HMW) adiponectin level in this cross-sectional study. A total of 1000 Japanese subjects who underwent medical check-ups were enrolled, and their plasma concentrations of 21 amino acids and clinical parameters were measured. The subjects without T2DM were divided into quartiles (Q1-4) by serum HMW adiponectin level, and the association with between PFAA concentrations was analysed. Concentrations of glutamate, alanine, proline, tyrosine, histidine, methionine, lysine, branched-chain amino acids (BCAAs) and tryptophan varied significantly according to the adiponectin quartile. Furthermore, serum adiponectin levels showed significant inverse correlations with these amino acids. The change in the PFAA profile in the group with the lowest adiponectin concentrations (Q1) was similar to that of T2DM patients. Although both adiponectin levels and PFAA concentrations are known to be altered by the accumulation of visceral fat and insulin resistance, the levels of glutamate, BCAA, lysine and tryptophan remain significantly associated with adiponectin level after adjustment for age, body mass index and homeostasis model assessment of insulin resistance, showing the direct association between PFAA concentrations and the serum HMW adiponectin level. Registration number: University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) UMIN000029920, registered on Nov 13th 2017 (prospectively registered).
Assuntos
Adiponectina , Aminoácidos , Diabetes Mellitus Tipo 2 , Humanos , Adiponectina/sangue , Aminoácidos/sangue , Estudos Transversais , População do Leste Asiático , Glutamatos , Resistência à Insulina , Lisina , Peso Molecular , TriptofanoRESUMO
A plethora of dimeric natural products exist with diverse chemical structures and biological activities. A major strategy for dimerization is aryl coupling catalyzed by cytochrome P450 or laccase. Actinorhodin (ACT) from Streptomyces coelicolor A3(2) has a dimeric pyranonaphthoquinone structure connected by a C-C bond. In this study, we identified an NmrA-family dimerizing enzyme, ActVA-ORF4, and a cofactor-independent oxidase, ActVA-ORF3, both involved in the last step of ACT biosynthesis. ActVA-ORF4 is a unique NAD(P)H-dependent enzyme that catalyzes the intermolecular C-C bond formation using 8-hydroxydihydrokalafungin (DHK-OH) as the sole substrate. On the other hand, ActVA-ORF3 was found to be a quinone-forming enzyme that produces the coupling substrate, DHK-OH and the final product, ACT. Consequently, the functional assignment of all essential enzymes in the biosynthesis of ACT, one of the best-known model natural products, has been completed.
Assuntos
Antraquinonas , Quinonas , Quinonas/química , Antraquinonas/química , Oxigenases de Função MistaRESUMO
Actinorhodin (ACT) is a benzoisochromanequinone antibiotic produced by Streptomyces coelicolor A3(2), which has served as a favored model organism for comprehensive studies of antibiotic biosynthesis and its regulation. (S)-DNPA undergoes various modifications as an intermediate in the ACT biosynthetic pathway, including enoyl reduction to DDHK. It has been suggested that actVI-ORF2 encodes an enoyl reductase (ER). However, its function has not been characterized in vitro. In this study, biochemical analysis of recombinant ActVI-ORF2 revealed that (S)-DNPA is converted to DDHK in a stereospecific manner with NADPH acting as a cofactor. (R)-DNPA was also reduced to 3-epi-DDHK with the comparable efficacy as (S)-DNPA, suggesting that the stereospecificity of ActVI-ORF2 was not affected by the stereochemistry at the C-3 of DNPA. ActVI-ORF2 is a new example of a discrete ER, which is distantly related to known ERs according to phylogenetic analysis.
Assuntos
Streptomyces coelicolor , Streptomyces , Antraquinonas/química , Antibacterianos/metabolismo , Oxirredutases/metabolismo , Filogenia , Piranos/metabolismo , Streptomyces/metabolismo , Streptomyces coelicolor/metabolismoRESUMO
"Idiopathic" is the most common category of uveitis, representing cases in which a specific diagnosis has not been established despite work-up. Sarcoidosis is a systemic granulomatous disorder affecting multiple organs including the lungs, skin, kidneys, and eyes. We used microRNA (miRNA) microarrays to investigate serum miRNA profiles of patients with ocular sarcoidosis as diagnosed by specific criteria (diagnosed ocular sarcoidosis), and patients with idiopathic uveitis characterized by ocular manifestations of sarcoidosis (suspected ocular sarcoidosis). Principal component analysis (PCA) and hierarchical clustering showed that serum miRNA profiles of diagnosed ocular sarcoidosis and suspected ocular sarcoidosis were both clearly distinguishable from healthy controls. Furthermore, comparative analysis of the miRNA profiles showed highly similar patterns between diagnosed ocular sarcoidosis and suspected ocular sarcoidosis. Pathway analysis revealed common pathways were involved in the two groups, including those of WNT signaling and TGF-beta signaling. Our study demonstrated a high overlap of differentially expressed serum miRNAs in patients with diagnosed ocular sarcoidosis and suspected ocular sarcoidosis, suggesting that these groups share a similar underlying pathology and may represent possible variants of the disease. Characterization of serum miRNA profiles may provide an opportunity for earlier diagnosis and treatment, and may inform more accurate clinical prognosis in patients with an ocular sarcoidosis phenotype.
Assuntos
Endoftalmite , MicroRNAs , Sarcoidose , Uveíte , Olho/patologia , Humanos , MicroRNAs/genética , Sarcoidose/diagnóstico , Sarcoidose/patologia , Fator de Crescimento Transformador beta , Uveíte/diagnóstico , Uveíte/genéticaRESUMO
Flavin-dependent monooxygenases are ubiquitous in living systems and are classified into single- or two-component systems. Actinorhodin, produced by Streptomyces coelicolor, is a representative polycyclic polyketide that is hydroxylated through the action of the two-component ActVA-5/ActVB hydroxylase system. These homologous systems are widely distributed in bacteria, but their reaction mechanisms remain unclear. This in vitro investigation has provided chemical proof of two consecutive hydroxylations via hydroxynaphthalene intermediates involved in actinorhodin biosynthesis. The ActVA-5 oxygenase component catalyzed a stepwise dihydroxylation of the substrate, whereas the ActVB flavin reductase not only supplied a reduced cofactor, but also regulated the quinone-hydroquinone interconversion of an intermediate. Our study provides clues for understanding the general biosynthetic mechanisms of highly functionalized aromatic natural products with structural diversity.
Assuntos
Antibacterianos/biossíntese , Oxigenases de Função Mista/metabolismo , Streptomyces coelicolor/metabolismo , Antraquinonas/metabolismo , Proteínas de Bactérias/metabolismo , Hidroxilação , CinéticaRESUMO
BACKGROUND: Gastric cancer after Helicobacter pylori (HP) eradication is a crucial clinical challenge today as HP eradication therapy is widely performed. Detecting gastric cancer after HP eradication tends to be difficult with normal white-light endoscopy. In the present study, we aimed to identify easily-evaluated endoscopic findings that indicate the presence of gastric cancer after HP eradication so that endoscopists can consider additional detailed examinations at the site. METHODS: We analyzed the endoscopic images of 43 patients who underwent endoscopic submucosal dissection for early gastric cancer after HP eradication and 119 patients with an HP eradication history who underwent esophagogastroduodenoscopy for a medical checkup. Endoscopic findings were evaluated according to the Kyoto classification of gastritis (atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness) and map-like redness. RESULTS: Patients with gastric cancer had significantly higher total Kyoto risk scores; more atrophy, intestinal metaplasia, and diffuse redness; and a significantly higher prevalence of map-like redness compared with those without gastric cancer, in the univariate analyses. We used logistic regression analysis with forward selection based on the likelihood ratio to develop a model using atrophy and diffuse redness. Receiver operating characteristic analysis showed that a score of A2 in the Kyoto classification of gastritis (open-type atrophic pattern in the Kimura-Takemoto classification) was an endoscopic marker for the presence of post-HP-eradication gastric cancer. CONCLUSIONS: Endoscopic severe gastric mucosal atrophy is useful to screen patients for gastric cancer after HP eradication.
Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Atrofia/patologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/patologia , Humanos , Metaplasia/patologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgiaRESUMO
BACKGROUND: The present comparative study with healthy volunteers was conducted to investigate the depressive status and temperament in patients with chronic thromboembolic pulmonary hypertension (CTEPH).MethodsâandâResults:The results of the temperament and personality scale test, and the Quick Inventory of Depressive Symptomatology-Self Report revealed that CTEPH patients have a significantly higher depressive status than healthy volunteers. CONCLUSIONS: It may be that CTEPH patients are more likely to have a depressive temperament in origin. It is expected that the relationship between the biological traits of CTEPH (e.g., genetics) and patients' depressive temperament will be elucidated in the future.
Assuntos
Depressão/psicologia , Hipertensão Pulmonar/psicologia , Embolia Pulmonar/psicologia , Idoso , Doença Crônica , Depressão/epidemiologia , Feminino , Humanos , Hipertensão Pulmonar/epidemiologia , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/epidemiologiaRESUMO
BACKGROUND AND AIMS: Infliximab is an efficacious agent used for the induction and maintenance of remission in Crohn's disease (CD), and recent studies suggested that it may also prevent the recurrence of this disease after surgery. The present study was performed to assess the efficacy and safety of infliximab in the postoperative setting, and to identify whether combination treatment with thiopurines had any additional beneficial effect as compared to mono-therapy. METHODS: We performed a retrospective cohort study to compare the efficacy of infliximab mono-therapy and combination treatment with a thiopurine in preventing recurrence after surgery. RESULTS: Forty-one patients who received infliximab as maintenance treatment following surgery from May 2002 to April 2010 were identified. Twenty-four were naive to infliximab, and 17 who underwent surgery during infliximab treatment were continued on it following surgery. The median follow-up period was 27 months (range 12-66 months). All patients continued infliximab as maintenance treatment, but 10 required dose intensification due to clinical recurrence. Kaplan-Meier analysis demonstrated that the use of concomitant thiopurine was correlated with the continuation of infliximab treatment at an 8-week interval (log-rank test p = 0.018). The rate of adverse event was 9.8% with no patient experiencing severe adverse reactions. CONCLUSION: Infliximab appears to be safe and it prevented clinical recurrence after surgery. Concomitant thiopurine use predicted response toward continuation of therapy at an 8-week interval. Prospective controlled studies to assess the efficacy of combination treatment in the postoperative setting are warranted.
Assuntos
Doença de Crohn/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Infliximab/uso terapêutico , Quimioterapia de Manutenção , Tionucleosídeos/uso terapêutico , Adulto , Doença de Crohn/prevenção & controle , Doença de Crohn/cirurgia , Quimioterapia Combinada/métodos , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Recidiva , Estudos Retrospectivos , Prevenção SecundáriaRESUMO
BACKGROUND: We evaluated the clinical efficacy of adalimumab (ADA) for Crohn's disease (CD) and analyzed predictive factors for clinical remission and long-term prognosis. METHODS: We retrospectively reviewed the medical records of 45 patients treated with ADA for CD at Keio University Hospital between October 2010 and March 2014. Clinical remission was defined as a Harvey-Bradshaw index of ≤4. RESULTS: Twenty-eight of 45 patients (62.2%) achieved clinical remission at week 4. Among these 28 patients, 18 patients (64.3%) maintained clinical remission at week 26, and among these, 16 patients (88.9%) maintained clinical remission at week 52. Absence of a history of bowel resection and absence of prior anti-tumor necrosis factor (anti-TNF) therapy were significant predictive factors for clinical remission at week 4 upon multivariate logistic regression analyses. Younger age and a disease duration of ≤3 years correlated with clinical remission at week 26 upon univariate analyses. Patients without a history of bowel resection showed significantly better long-term prognosis than those with a history of bowel resection (p = 0.01). None of the patients contracted a serious infectious disease. CONCLUSIONS: Younger age, shorter duration of disease, being naive to anti-TNF antagonists, and absence of a history of bowel resection were associated with the efficacy of ADA in CD patients.
Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Doença de Crohn/tratamento farmacológico , Adalimumab , Adolescente , Adulto , Idoso , Intervenção Médica Precoce , Feminino , Humanos , Intestinos/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto JovemRESUMO
BACKGROUND AND AIMS: Infliximab (IFX) is a monoclonal antibody used to treat patients with Crohn's disease (CD). Intra-abdominal abscess formation is a major complication of CD with negative effects on patient prognosis. We have analyzed risk factors for abscess formation in CD patients treated with IFX. METHODS: CD patients who received IFX between January 2000 and April 2011 at Keio University Hospital were analyzed retrospectively. Risk factors for abscess formation were assessed by univariate and multivariate logistic regression analyses. RESULTS: Intra-abdominal abscess was seen in 15 of 258 patients. Univariate analyses showed serum C-reactive protein (CRP) concentration at 14 weeks after initiation of IFX (p = 0.021), serum albumin concentration at week 0 (p = 0.022) and week 14 (p = 0.004), the presence of anal lesions (p = 0.036), progression of intestine deformation (p = 0.015) and early loss of response to IFX (p < 0.0001) to be risk factors. Multivariate analysis showed that CRP concentration at 14 weeks [odds ratio (OR) 1.361] and loss of IFX response within 6 months (OR 5.361) were independent risk factors. CONCLUSIONS: Abscess formation should be suspected in patients with symptoms of CD recurrence during IFX therapy. Uncontrolled CRP concentration and early loss of response to IFX are risk factors.
Assuntos
Abscesso Abdominal/etiologia , Anticorpos Monoclonais/uso terapêutico , Doença de Crohn/complicações , Doença de Crohn/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Abscesso Abdominal/epidemiologia , Abscesso Abdominal/cirurgia , Proteína C-Reativa/análise , Progressão da Doença , Feminino , Humanos , Infliximab , Masculino , Estudos Retrospectivos , Medição de Risco , Fatores de RiscoRESUMO
The bacterial alarmone ppGpp is present only in bacteria and the chloroplasts of plants, but not in mammalian cells or eukaryotic micro-organisms such as yeasts and fungi. The importance of the ppGpp signalling system in eukaryotes has therefore been largely overlooked. Here, we demonstrated that heterologous expression of a relA-spoT homologue (Sj-RSH) isolated from the halophilic plant Suaeda japonica in the yeast Saccharomyces cerevisiae results in accumulation of ppGpp, accompanied by enhancement of tolerance against various stress stimuli, such as osmotic stress, ethanol, hydrogen peroxide, high temperature and freezing. Unlike bacterial ppGpp accumulation, ppGpp was accumulated in the early growth phase but not in the late growth phase. Moreover, nutritional downshift resulted in a decrease in ppGpp level, suggesting that the observed Sj-RSH activity to synthesize ppGpp is not starvation-dependent, contrary to our expectations based on bacteria. Accumulated ppGpp was found to be present solely in the cytosolic fraction and not in the mitochondrial fraction, perhaps reflecting the ribosome-independent ppGpp synthesis in S. cerevisiae cells. Unlike bacterial inosine monophosphate (IMP) dehydrogenases, the IMP dehydrogenase of S. cerevisiae was insensitive to ppGpp. Microarray analysis showed that ppGpp accumulation gave rise to marked changes in gene expression, with both upregulation and downregulation, including changes in mitochondrial gene expression. The most prominent upregulation (38-fold) was detected in the hypothetical gene YBR072C-A of unknown function, followed by many other known stress-responsive genes. S. cerevisiae may provide new opportunities to uncover and analyse the ppGpp signalling system in eukaryotic cells.
Assuntos
Chenopodiaceae/enzimologia , Expressão Gênica , Nucleotídeos de Guanina/metabolismo , Ligases/genética , Proteínas de Plantas/genética , Pirofosfatases/genética , Saccharomyces cerevisiae/fisiologia , Chenopodiaceae/genética , Regulação Fúngica da Expressão Gênica , Ligases/metabolismo , Proteínas de Plantas/metabolismo , Pirofosfatases/metabolismo , Saccharomyces cerevisiae/genética , Estresse FisiológicoRESUMO
An oxygenated derivative of dihydrokalafungin (DHK) was isolated from a deletion mutant of the actVA-ORF4 gene involved in the biosynthesis of a dimeric benzoisochromanequinone (BIQ) antibiotic, actinorhodin (ACT), in Streptomyces coelicolor A3(2). Spectroscopic analysis elucidated its structure as 8-hydroxy-DHK, corresponding to the monomeric unit of ACT. Further metabolite analysis identified its related compound, clearly derived from the reduction of 8-hydroxy-DHK. The structures of these metabolites indicate the essential role of ActVA-ORF4 in ACT biosynthesis, specifically in dimerization of a BIQ intermediate via C-C bond formation.
Assuntos
Antibacterianos/biossíntese , Proteínas de Bactérias/metabolismo , Streptomyces coelicolor/metabolismo , Antraquinonas/análise , Antraquinonas/metabolismo , Antibacterianos/análise , Proteínas de Bactérias/genética , Cromatografia Líquida de Alta Pressão , Deleção de Genes , Espectroscopia de Ressonância Magnética , Mutação , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Lamina propria macrophages (LPMs) spontaneously produce large amounts of anti-inflammatory IL-10 and play a central role in regulation of immune responses against commensal bacteria. MCP-1 is a chemokine that plays an important role in recruitment of monocytes and macrophages to inflamed tissues. We demonstrated that, in addition to IL-10, LPMs produced large amounts of MCP-1, even in a steady state. MCP-1 deficiency caused impaired IL-10 production by LPMs and led to exacerbation of dextran sulfate sodium-induced acute colitis. As an explanation of this impaired IL-10 production by LPMs, we found that LPMs could be separated into two subsets with distinct side-scattered properties, namely LPM1 (CD11b(+)F4/80(+)CD11c(-)SSC(hi)) and LPM2 (CD11b(+)F4/80(+)CD11c(-)SSC(lo)). Unlike LPM1, the LPM2 subset migrated in response to MCP-1 and produced a larger amount of IL-10 in response to commensal bacteria. LPMs isolated from MCP-1-deficient mice produced less IL-10 as a consequence of the lack of the MCP-1-dependent LPM2 population. This imbalanced composition in LPM population may be involved in the susceptibility to DSS-induced colitis in MCP-1-deficient mice. Our results suggest that endogenous MCP-1 contributes to the composition of resident LPM subsets in the intestine. Moreover, MCP-1-dependent LPM2 subset may play an important role in maintenance of gut homeostasis in the steady state, and in the termination of excess inflammatory responses in the intestine, by producing IL-10.
Assuntos
Quimiocina CCL2/fisiologia , Inflamação/metabolismo , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Animais , Antígenos de Bactérias/imunologia , Antígeno CD11b/metabolismo , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Sulfato de Dextrana , Enterococcus faecalis/imunologia , Feminino , Citometria de Fluxo , Homeostase , Interleucina-10/genética , Intestinos/patologia , Ativação de Macrófagos/imunologia , Macrófagos/classificação , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/metabolismoRESUMO
PURPOSE: Crohn's disease (CD) commonly recurs after surgery, and a number of patients need repeated surgery, especially smokers and those with repeated surgeries or penetrating disease. Whether infliximab prevents postsurgical recurrence in high-risk CD remains unknown. In the present pilot open-labeled study, we investigated the safety and efficacy of scheduled infliximab, which was started early after surgery, in maintaining remission of CD patients who have undergone multiple surgeries due to penetrating disease. METHODS: Eleven patients (nine male, two female; age range, 26-48 years) who had undergone repeated surgeries (median, 4; range, 2-5) for penetrating disease were enrolled. Two to 4 weeks after surgery, the patients were started on intravenous infliximab (5 mg/kg) at an 8-week interval. The primary end points were the proportion of patients in clinical remission at the end of the study, the rate of endoscopic/radiologic remission at 24 months, and the rate of adverse effects. RESULTS: One patient dropped out due to non-compliance, and ten patients were eligible for analysis. Clinical remission was maintained in six of ten patients (60.0%) at the end of the study. At 24 months, four out of ten patients were in endoscopic or radiological remission (40.0%). Two patients experienced adverse effects (18.2%), one of whom elected to withdraw from the study. CONCLUSION: The findings of no major safety concern and possible clinical benefit in our study suggest that further investigation of infliximab as a treatment for prevention of postsurgical recurrence in high-risk CD is warranted.
Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/prevenção & controle , Adulto , Doença de Crohn/cirurgia , Feminino , Seguimentos , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Indução de Remissão , Prevenção Secundária , Resultado do TratamentoRESUMO
Intestinal macrophages play a central role in regulation of immune responses against commensal bacteria. In general, intestinal macrophages lack the expression of innate-immune receptor CD14 and do not produce proinflammatory cytokines against commensal bacteria. In this study, we identified what we believe to be a unique macrophage subset in human intestine. This subset expressed both macrophage (CD14, CD33, CD68) and DC markers (CD205, CD209) and produced larger amounts of proinflammatory cytokines, such as IL-23, TNF-alpha, and IL-6, than typical intestinal resident macrophages (CD14-CD33+ macrophages). In patients with Crohn disease (CD), the number of these CD14+ macrophages were significantly increased compared with normal control subjects. In addition to increased numbers of cells, these cells also produced larger amounts of IL-23 and TNF-alpha compared with those in normal controls or patients with ulcerative colitis. In addition, the CD14+ macrophages contributed to IFN-gamma production rather than IL-17 production by lamina propria mononuclear cells (LPMCs) dependent on IL-23 and TNF-alpha. Furthermore, the IFN-gamma produced by LPMCs triggered further abnormal macrophage differentiation with an IL-23-hyperproducing phenotype. Collectively, these data suggest that this IL-23/IFN-gamma-positive feedback loop induced by abnormal intestinal macrophages contributes to the pathogenesis of chronic intestinal inflammation in patients with CD.
Assuntos
Doença de Crohn/genética , Interferon gama/metabolismo , Interleucina-23/metabolismo , Receptores de Lipopolissacarídeos/biossíntese , Macrófagos/metabolismo , Antígenos CD/biossíntese , Antígenos de Diferenciação Mielomonocítica/biossíntese , Diferenciação Celular , Separação Celular , Doença de Crohn/metabolismo , Citometria de Fluxo , Humanos , Inflamação , Mucosa Intestinal/patologia , Modelos Biológicos , Monócitos/metabolismo , Mucosa/metabolismo , Lectina 3 Semelhante a Ig de Ligação ao Ácido SiálicoRESUMO
BACKGROUND & AIMS: Mucosal natural killer (NK) cells that produce interleukin (IL)-22 mediate intestinal homeostasis and inflammation in mice. However, their role in the pathogenesis of human inflammatory bowel diseases (IBDs) is not known. We investigated intestinal NK cells in intestinal mucosa samples of patients with Crohn's disease (CD). METHODS: We isolated lamina propria NK cells from intestinal mucosal samples of patients with IBD and subjects without IBD (controls) and analyzed expression patterns of cell surface molecules and cytokine production. Interactions between lamina propria NK cells and intestinal macrophages were examined. RESULTS: In intestinal mucosa samples from controls, NKp44 and NKp46 were expressed differentially on CD3(-)CD56(+) NK cells, NKp44(+)NKp46(-) (NKp44(+)) NK cells expressed CD127 and the transcription factor retinoic acid-related orphan receptor C (RORC) and produced IL-22 whereas NKp44(-)NKp46(+) (NKp46(+)) NK cells did not express CD127 or RORC and produced interferon (IFN)-gamma. NKp46(+) NK cells were predominant in intestinal mucosa of patients with CD compared with controls or patients with ulcerative colitis. Upon interaction with intestinal inflammatory macrophages NKp46(+), NK cells from patients with CD were activated via IL-23 and produced IFN-gamma; this activation required cell-to-cell contact. CONCLUSIONS: The balance of NKp44(+)/NKp46(+) NK cells is disrupted in intestinal mucosa of patients with CD. NKp46(+) NK cells might mediate the pathogenesis of CD by producing IFN-gamma.
Assuntos
Doença de Crohn/imunologia , Mucosa Intestinal/imunologia , Intestino Grosso/imunologia , Células Matadoras Naturais/imunologia , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Receptor 2 Desencadeador da Citotoxicidade Natural/metabolismo , Complexo CD3/metabolismo , Antígeno CD56/metabolismo , Estudos de Casos e Controles , Comunicação Celular , Células Cultivadas , Técnicas de Cocultura , Doença de Crohn/patologia , Enterococcus faecalis/imunologia , Escherichia coli/imunologia , Humanos , Imunofenotipagem , Interferon gama/metabolismo , Interleucina-23/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Interleucinas/metabolismo , Mucosa Intestinal/patologia , Intestino Grosso/patologia , Células Matadoras Naturais/microbiologia , Macrófagos/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Interleucina 22RESUMO
Th17 cells and Th1 cells coordinate to play a critical role in the formation of inflammatory bowel diseases. To examine how Th17 and Th1 cells are regulated at inflammatory sites, we used Th1-dominant CD4(+)CD45RB(high) T cell-transferred RAG-2(-/-) and Th1/Th17-mixed IL-10(-/-) mice. Interestingly, not only did colitic RAG-2(-/-) mice that were parabiosed with WT mice show significant amelioration of colitis, but amelioration of disease was also observed in those parabiosed with colitic IL-10(-/-) mice. To assess the interference between Th1 and Th17 colitogenic T cells, we co-transferred colitogenic CD4(+) T cells from the lamina propria (LP) of CD4(+)CD45RB(high) T cell-transferred RAG-2(-/-) mice and IL-10(-/-) mice into RAG-2(-/-) mice. Surprisingly, the co-transferred RAG-2(-/-) mice showed a vast cellular infiltration of LP CD4(+) T cells similar to that seen in RAG-2(-/-) mice re-transferred with the cells from colitic RAG-2(-/-) mice alone, but the co-transferred RAG-2(-/-) mice did not have the wasting symptoms, which are also absent in RAG-2(-/-) mice transferred with cells from colitic IL-10(-/-) mice alone. Furthermore, the percentages of Th1 and Th17 cells originating from IL-10(-/-) mice and those of Th1 cells originating from colitic RAG-2(-/-) mice were all significantly decreased in the co-transferred mice as compared with the singly-transferred paired RAG-2(-/-) mice, suggesting that Th1 and Th17 cells are in competition, and that their orchestration results in a merged clinical phenotype of the two types of murine colitis.
Assuntos
Comunicação Celular , Colite/imunologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa/imunologia , Células Th1/metabolismo , Transferência Adotiva , Animais , Antígenos CD4/biossíntese , Comunicação Celular/imunologia , Colite/patologia , Colite/fisiopatologia , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Humanos , Interleucina-10/genética , Interleucina-17/metabolismo , Antígenos Comuns de Leucócito/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mucosa/patologia , Parabiose , Células Th1/imunologia , Células Th1/patologiaRESUMO
The biosynthetic gene cluster of the aromatic polyketide antibiotic actinorhodin (ACT) in Streptomyces coelicolor A3(2) carries a pair of genes, actVA-ORF5 and actVB, that encode a two-component flavin-dependent monooxygenase (FMO). Our previous studies have demonstrated that the ActVA-ORF5/ActVB system functions as a quinone-forming C-6 oxygenase in ACT biosynthesis. Furthermore, we found that this enzyme system exhibits an additional oxygenation activity with dihydrokalafungin (DHK), a proposed intermediate in the ACT biosynthetic pathway, and generates two reaction products. These compounds were revealed to be monooxygenated derivatives of kalafungin, which is spontaneously formed through oxidative lactonization of DHK. Their absolute structures were elucidated from their NMR spectroscopic data and by computer modeling and X-ray crystallography as (5S,14R)-epoxykalafungin and (5R,14S)-epoxykalafungin, demonstrating an additional epoxyquinone-forming activity of the ActVA-ORF5/ActVB system in vitro.
Assuntos
Antibacterianos/metabolismo , Compostos de Epóxi/química , Flavinas/metabolismo , Oxigenases de Função Mista/metabolismo , Quinonas/metabolismo , Antraquinonas/metabolismo , Catálise , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Quinonas/químicaRESUMO
Intestinal APCs are considered critical in maintaining the balance between the response against harmful pathogens and the induction of tolerance to commensal bacteria and food Ags. Recently, several studies indicated the presence of gut-specific APC subsets, which possess both macrophage and dendritic cell (DC) markers. These unique APC subsets play important roles in gut immunity, especially for immune regulation against commensal bacteria. Herein, we examined a unique macrophage subset, which coexpressed the macrophage (Mphi) marker CD14 and the DC marker CD209 in human intestinal lamina propria (LP). The LP Mphi subset in both normal control subjects or Crohn's disease (CD) patients induced proliferation of naive CD4(+) T cells as well as monocyte-derived DCs, and it expressed retinoic acid synthetic enzyme retinaldehyde dehydrogenase 2 and retinol dehydrogenase 10, which induced expression of gut homing receptors on T cells in a retinoic acid-dependent manner. Moreover, the LP Mphi subset strongly evoked differentiation of Th1 cells and slightly induced Th17 cells in both normal control subjects and CD patients; the inducing potential was highest in CD patients. In CD patients, Th17, but not Th1, induction by the LP Mphi subset was enhanced in the presence of commensal bacteria Ags. This enhancement was not observed in normal control subjects. The Th17 induction by the LP Mphi subset was inhibited by neutralization of IL-6 and IL-1beta, but it was enhanced by blockade of retinoic acid signaling. These observations highlight a role for LP Mphi in the enhanced Th1, and potentially in Th17 differentiation, at the inflammatory site of inflammatory bowel diseases.
Assuntos
Apresentação de Antígeno/imunologia , Receptores de Lipopolissacarídeos , Macrófagos/imunologia , Mucosa/imunologia , Estudos de Casos e Controles , Moléculas de Adesão Celular , Diferenciação Celular , Doença de Crohn , Humanos , Inflamação/imunologia , Interleucina-17 , Intestinos/citologia , Intestinos/imunologia , Lectinas Tipo C , Teste de Cultura Mista de Linfócitos , Receptores de Superfície Celular , Células Th1RESUMO
Predicting the response of patients with ulcerative colitis (UC) to a biologic such as vedolizumab (VDZ) before administration is an unmet need for optimizing individual patient treatment. We hypothesized that the machine-learning approach with daily clinical information can be a new, promising strategy for developing a drug-efficacy prediction tool. Random forest with grid search and cross-validation was employed in Cohort 1 to determine the contribution of clinical features at baseline (week 0) to steroid-free clinical remission (SFCR) with VDZ at week 22. Among 49 clinical features including sex, age, height, body weight, BMI, disease duration/phenotype, treatment history, clinical activity, endoscopic activity, and blood test items, the top eight features (partial Mayo score, MCH, BMI, BUN, concomitant use of AZA, lymphocyte fraction, height, and CRP) were selected for logistic regression to develop a prediction model for SFCR at week 22. In the validation using the external Cohort 2, the positive and negative predictive values of the prediction model were 54.5% and 92.3%, respectively. The prediction tool appeared useful for identifying patients with UC who would not achieve SFCR at week 22 during VDZ therapy. This study provides a proof-of-concept that machine learning using real-world data could permit personalized treatment for UC.