RESUMO
Chronic inflammation drives the progression of colorectal cancer (CRC). Increased expression of interleukin (IL)-17A is associated with poor prognosis, and IL-17A blockade curbs tumor progression in preclinical models of CRC. Here we examined the impact of IL-1 signaling, a key regulator of the IL-17 pathway, in different cell types within the CRC microenvironment. Genetic deletion of the IL-1 receptor (IL-1R1) in epithelial cells alleviated tumorigenesis in the APC model of CRC, demonstrating a cell-autonomous role for IL-1 signaling in early tumor seed outgrowth. T cell specific ablation of IL-1R1 decreased tumor-elicited inflammation dependent on IL-17 and IL-22, thereby reducing CRC progression. The pro-tumorigenic roles of IL-1 were counteracted by its effects on myeloid cells, particularly neutrophils, where IL-1R1 ablation resulted in bacterial invasion into tumors, heightened inflammation and aggressive CRC progression. Thus, IL-1 signaling elicits cell-type-specific responses, which, in aggregate, set the inflammatory tone of the tumor microenvironment and determine the propensity for disease progression.
Assuntos
Neoplasias Colorretais/imunologia , Inflamação/metabolismo , Interleucina-17/metabolismo , Interleucina-1/metabolismo , Neutrófilos/imunologia , Salmonelose Animal/imunologia , Salmonella/imunologia , Animais , Carcinogênese , Células Cultivadas , Humanos , Interleucina-1/genética , Interleucina-1/imunologia , Interleucinas/metabolismo , Camundongos , Camundongos Knockout , Neutrófilos/ultraestrutura , Especificidade de Órgãos , Receptores de Interleucina-1/genética , Transdução de Sinais , Microambiente Tumoral , Interleucina 22RESUMO
Although commensal flora is involved in the regulation of immunity, the interplay between cytokine signaling and microbiota in atherosclerosis remains unknown. We found that interleukin (IL)-23 and its downstream target IL-22 restricted atherosclerosis by repressing pro-atherogenic microbiota. Inactivation of IL-23-IL-22 signaling led to deterioration of the intestinal barrier, dysbiosis, and expansion of pathogenic bacteria with distinct biosynthetic and metabolic properties, causing systemic increase in pro-atherogenic metabolites such as lipopolysaccharide (LPS) and trimethylamine N-oxide (TMAO). Augmented disease in the absence of the IL-23-IL-22 pathway was mediated in part by pro-atherogenic osteopontin, controlled by microbial metabolites. Microbiota transfer from IL-23-deficient mice accelerated atherosclerosis, whereas microbial depletion or IL-22 supplementation reduced inflammation and ameliorated disease. Our work uncovers the IL-23-IL-22 signaling as a regulator of atherosclerosis that restrains expansion of pro-atherogenic microbiota and argues for informed use of cytokine blockers to avoid cardiovascular side effects driven by microbiota and inflammation.
Assuntos
Aterosclerose/etiologia , Aterosclerose/metabolismo , Dieta , Microbioma Gastrointestinal , Homeostase , Interleucina-23/metabolismo , Interleucinas/metabolismo , Animais , Aterosclerose/patologia , Biomarcadores , Modelos Animais de Doenças , Progressão da Doença , Expressão Gênica , Imunofenotipagem , Interleucina-23/deficiência , Metabolismo dos Lipídeos , Camundongos , Camundongos Knockout , Osteopontina/genética , Osteopontina/metabolismo , Transdução de Sinais , Interleucina 22RESUMO
An efficacious human immunodeficiency virus (HIV) vaccine will likely require induction of both mucosal and systemic immune responses. We compared the immunogenicity and protective efficacy of two mucosal/systemic vaccine regimens and investigated their effects on the rectal microbiome. Rhesus macaques were primed twice mucosally with replication-competent adenovirus type 5 host range mutant (Ad5hr)-simian immunodeficiency virus (SIV) recombinants and boosted twice intramuscularly with ALVAC-SIV recombinant plus SIV gp120 protein or with DNA for SIV genes and rhesus interleukin-12 plus SIV gp120 protein. Controls received empty Ad5hr vector and alum adjuvant only. Both regimens elicited strong, comparable mucosal and systemic cellular and humoral immunity. Prevaccination rectal microbiomes of males and females differed and significantly changed over the course of immunization, most strongly in females after Ad5hr immunizations. Following repeated low-dose intrarectal SIV challenges, both vaccine groups exhibited modestly but significantly reduced acute viremia. Male and female controls exhibited similar acute viral loads; however, vaccinated females, but not males, exhibited lower levels of acute viremia, compared to same-sex controls. Few differences in adaptive immune responses were observed between the sexes. Striking differences in correlations of the rectal microbiome of males and females with acute viremia and immune responses associated with protection were seen and point to effects of the microbiome on vaccine-induced immunity and viremia control. Our study clearly demonstrates direct effects of a mucosal SIV vaccine regimen on the rectal microbiome and validates our previously reported SIV vaccine-induced sex bias. Sex and the microbiome are critical factors that should not be overlooked in vaccine design and evaluation.IMPORTANCE Differences in HIV pathogenesis between males and females, including immunity postinfection, have been well documented, as have steroid hormone effects on the microbiome, which is known to influence mucosal immune responses. Few studies have applied this knowledge to vaccine trials. We investigated two SIV vaccine regimens combining mucosal priming immunizations and systemic protein boosting. We again report a vaccine-induced sex bias, with female rhesus macaques but not males displaying significantly reduced acute viremia. The vaccine regimens, especially the mucosal primes, significantly altered the rectal microbiome. The greatest effects were in females. Striking differences between female and male macaques in correlations of prevalent rectal bacteria with viral loads and potentially protective immune responses were observed. Effects of the microbiome on vaccine-induced immunity and viremia control require further study by microbiome transfer. However, the findings presented highlight the critical importance of considering effects of sex and the microbiome in vaccine design and evaluation.
Assuntos
Imunização Secundária/métodos , Macaca mulatta/imunologia , Microbiota/efeitos dos fármacos , Reto/microbiologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Viremia/imunologia , Vacinas contra a AIDS/imunologia , Adenoviridae/genética , Animais , Feminino , Imunidade Humoral , Imunidade nas Mucosas , Masculino , Microbiota/fisiologia , Reto/imunologia , Vacinas contra a SAIDS/imunologiaRESUMO
In humans, bone marrow (BM) failure syndromes, both constitutional and acquired, predispose to myeloid malignancies. We have modeled acquired immune aplastic anemia, the paradigmatic disease of these syndromes, in the mouse by infusing lymph node cells from specific pathogen-free (SPF) CD45.1 congenic C57BL/6 (B6) donors into hybrid CByB6F1 recipients housed either in conventional (CVB) or SPF facilities. The severity of BM damage was reduced in CVB recipients; they also had reduced levels of CD44+ CD62L- effector memory T cells, reduced numbers of donor-type CD44+ T cells, and reduced expansion of donor-type CD8 T cells carrying T-cell receptor ß-variable regions 07, 11, and 17. Analyses of fecal samples through 16S ribosomal RNA amplicon sequencing revealed greater gut microbial alpha diversity in CVB mice relative to that of SPF mice. Thus, the presence of a broader spectrum of gut microorganisms in CVB-housed CByB6F1 could have primed recipient animal's immune system leading to suppression of allogeneic donor T-cell activation and expansion and attenuation of host BM destruction. These results suggest the potential benefit of diverse gut microbiota in patients receiving BM transplants.
Assuntos
Anemia Aplástica/terapia , Transplante de Medula Óssea/métodos , Medula Óssea/imunologia , Microbioma Gastrointestinal/imunologia , Linfócitos T/imunologia , Anemia Aplástica/imunologia , Anemia Aplástica/patologia , Animais , Medula Óssea/patologia , Fezes/microbiologia , Receptores de Hialuronatos/imunologia , Receptores de Hialuronatos/metabolismo , Memória Imunológica/imunologia , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Organismos Livres de Patógenos Específicos , Linfócitos T/metabolismo , Linfócitos T/transplante , Imunologia de Transplantes , Transplante HomólogoRESUMO
Low grade, chronic inflammation is a critical risk factor for immunologic dysfunction including autoimmune diseases. However, the multiplicity of complex mechanisms and lack of relevant murine models limit our understanding of the precise role of chronic inflammation. To address these hurdles, we took advantage of multi-omics data and a unique murine model with a low but chronic expression of IFN-γ, generated by replacement of the AU-rich element (ARE) in the 3' UTR region of IFN-γ mRNA with random nucleotides. Herein, we demonstrate that low but differential expression of IFN-γ in mice by homozygous or heterozygous ARE replacement triggers distinctive gut microbial alterations, of which alteration is female-biased with autoimmune-associated microbiota. Metabolomics data indicates that gut microbiota-dependent metabolites have more robust sex-differences than microbiome profiling, particularly those involved in fatty acid oxidation and nuclear receptor signaling. More importantly, homozygous ARE-Del mice have dramatic changes in tryptophan metabolism, bile acid and long-chain lipid metabolism, which interact with gut microbiota and nuclear receptor signaling similarly with sex-dependent metabolites. Consistent with these findings, nuclear receptor signaling, encompassing molecules such as PPARs, FXR, and LXRs, was detectable as a top canonical pathway in comparison of blood and tissue-specific gene expression between female homozygous vs heterozygous ARE-Del mice. Further analysis implies that dysregulated autophagy in macrophages is critical for breaking self-tolerance and gut homeostasis, while pathways interact with nuclear receptor signaling to regulate inflammatory responses. Overall, pathway-based integration of multi-omics data provides systemic and cellular insights about how chronic inflammation driven by IFN-γ results in the development of autoimmune diseases with specific etiopathological features.
Assuntos
Doenças Autoimunes/imunologia , Disbiose/imunologia , Inflamação/imunologia , Interferon gama/metabolismo , Macrófagos/imunologia , Regiões 3' não Traduzidas/genética , Elementos Ricos em Adenilato e Uridilato/genética , Animais , Autofagia , Doença Crônica , Feminino , Microbioma Gastrointestinal/imunologia , Interferon gama/genética , Masculino , Camundongos , Camundongos Knockout , Receptores Citoplasmáticos e Nucleares/metabolismo , Sexismo , Transdução de SinaisRESUMO
Commensal bacteria are critical for physiological functions in the gut, and dysbiosis in the gut may cause diseases. In this article, we report that mice deficient in cathelin-related antimicrobial peptide (CRAMP) were defective in the development of colon mucosa and highly sensitive to dextran sulfate sodium (DSS)-elicited colitis, as well as azoxymethane-mediated carcinogenesis. Pretreatment of CRAMP-/- mice with antibiotics markedly reduced the severity of DSS-induced colitis, suggesting CRAMP as a limiting factor on dysbiosis in the colon. This was supported by observations that wild-type (WT) mice cohoused with CRAMP-/- mice became highly sensitive to DSS-induced colitis, and the composition of fecal microbiota was skewed by CRAMP deficiency. In particular, several bacterial species that are typically found in oral microbiota, such as Mogibacterium neglectum, Desulfovibrio piger, and Desulfomicrobium orale, were increased in feces of CRAMP-/- mice and were transferred to WT mice during cohousing. When littermates of CRAMP+/- parents were examined, the composition of the fecal microbiota of WT pups and heterozygous parents was similar. In contrast, although the difference in fecal microbiota between CRAMP-/- and WT pups was small early on after weaning and single mouse housing, there was an increasing divergence with prolonged single housing. These results indicate that CRAMP is critical in maintaining colon microbiota balance and supports mucosal homeostasis, anti-inflammatory responses, and protection from carcinogenesis.
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Peptídeos Catiônicos Antimicrobianos/metabolismo , Colo/metabolismo , Colo/microbiologia , Microbioma Gastrointestinal/fisiologia , Homeostase/fisiologia , Microbiota/fisiologia , Animais , Colite/metabolismo , Colite/microbiologia , Modelos Animais de Doenças , Fezes/microbiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas/metabolismo , CatelicidinasRESUMO
Specific-pathogen-free (SPF) mice have improved hematopoietic characteristics relative to germ-free mice, however, it is not clear whether improvements in hematopoietic traits will continue when the level of microorganism exposure is further increased. We co-housed SPF C57BL/6 mice in a conventional facility (CVT) and found a significant increase in gut microbiota diversity along with increased levels of myeloid cells and T cells, especially effector memory T cells. Through single cell RNA sequencing of sorted KL (c-Kit+Lin-) cells, we imputed a decline in long-term hematopoietic stem cells and an increase in granulocyte-monocyte progenitors in CVT mice with up-regulation of genes associated with cell survival. Bone marrow transplantation through competitive repopulation revealed a significant increase in KSL (c-Kit+Sca-1+Lin-) cell reconstitution in recipients of CVT donor cells which occurred when donors were co-housed for both one and twelve months. However, there was minimal to no gain in mature blood cell engraftment in recipients of CVT donor cells relative to those receiving SPF donor cells. We conclude that co-housing SPF mice with mice born in a conventional facility increased gut microbiota diversity, augmented myeloid cell production and T cell activation, stimulated KSL cell reconstitution, and altered hematopoietic gene expression.
Assuntos
Bactérias/classificação , Perfilação da Expressão Gênica/métodos , Hematopoese , Células Mieloides/metabolismo , Análise de Sequência de RNA/métodos , Linfócitos T/metabolismo , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Transplante de Medula Óssea , Microbioma Gastrointestinal , Regulação da Expressão Gênica , Abrigo para Animais , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Filogenia , Análise de Célula Única , Organismos Livres de Patógenos EspecíficosRESUMO
Individuals with type 1 diabetes (T1D) often have higher than normal blood glucose levels, causing advanced glycation end product formation and inflammation and increasing the risk of vascular complications years or decades later. To examine the urinary proteome in juveniles with T1D for signatures indicative of inflammatory consequences of hyperglycemia, we profiled the proteome of 40 T1D patients with an average of 6.3 years after disease onset and normal or elevated HbA1C levels, in comparison with a cohort of 41 healthy siblings. Using shotgun proteomics, 1036 proteins were identified, on average, per experiment, and 50 proteins showed significant abundance differences using a Wilcoxon signed-rank test (FDR q-value ≤ 0.05). Thirteen lysosomal proteins were increased in abundance in the T1D versus control cohort. Fifteen proteins with functional roles in vascular permeability and adhesion were quantitatively changed, including CD166 antigen and angiotensin-converting enzyme 2. α-N-Acetyl-galactosaminidase and α-fucosidase 2, two differentially abundant lysosomal enzymes, were detected in western blots with often elevated quantities in the T1D versus control cohort. Increased release of proteins derived from lysosomes and vascular epithelium into urine may result from hyperglycemia-associated inflammation in the kidney vasculature.
Assuntos
Diabetes Mellitus Tipo 1/urina , Enzimas/urina , Proteoma/metabolismo , Proteômica/métodos , Irmãos , Molécula de Adesão de Leucócito Ativado/metabolismo , Molécula de Adesão de Leucócito Ativado/urina , Adolescente , Enzima de Conversão de Angiotensina 2 , Western Blotting , Criança , Cromatografia Líquida , Estudos de Coortes , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/metabolismo , Enzimas/metabolismo , Feminino , Humanos , Lisossomos/enzimologia , Lisossomos/metabolismo , Masculino , Peptidil Dipeptidase A/metabolismo , Peptidil Dipeptidase A/urina , Espectrometria de Massas em Tandem , alfa-L-Fucosidase/metabolismo , alfa-L-Fucosidase/urina , alfa-N-Acetilgalactosaminidase/metabolismo , alfa-N-Acetilgalactosaminidase/urinaRESUMO
Accurately calling indels with next-generation sequencing (NGS) data is critical for clinical application. The precisionFDA team collaborated with the U.S. Food and Drug Administration's (FDA's) National Center for Toxicological Research (NCTR) and successfully completed the NCTR Indel Calling from Oncopanel Sequencing Data Challenge, to evaluate the performance of indel calling pipelines. Top performers were selected based on precision, recall, and F1-score. The performance of many other pipelines was close to the top performers, which produced a top cluster of performers. The performance was significantly higher in high confidence regions and coding regions, and significantly lower in low complexity regions. Oncopanel capture and other issues may have occurred that affected the recall rate. Indels with higher variant allele frequency (VAF) may generally be called with higher confidence. Many of the indel calling pipelines had good performance. Some of them performed generally well across all three oncopanels, while others were better for a specific oncopanel. The performance of indel calling can further be improved by restricting the calls within high confidence intervals (HCIs) and coding regions, and by excluding low complexity regions (LCR) regions. Certain VAF cut-offs could be applied according to the applications.
Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Mutação INDEL , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The COVID-19 pandemic had disproportionate effects on the Veteran population due to the increased prevalence of medical and environmental risk factors. Synthetic electronic health record (EHR) data can help meet the acute need for Veteran population-specific predictive modeling efforts by avoiding the strict barriers to access, currently present within Veteran Health Administration (VHA) datasets. The U.S. Food and Drug Administration (FDA) and the VHA launched the precisionFDA COVID-19 Risk Factor Modeling Challenge to develop COVID-19 diagnostic and prognostic models; identify Veteran population-specific risk factors; and test the usefulness of synthetic data as a substitute for real data. The use of synthetic data boosted challenge participation by providing a dataset that was accessible to all competitors. Models trained on synthetic data showed similar but systematically inflated model performance metrics to those trained on real data. The important risk factors identified in the synthetic data largely overlapped with those identified from the real data, and both sets of risk factors were validated in the literature. Tradeoffs exist between synthetic data generation approaches based on whether a real EHR dataset is required as input. Synthetic data generated directly from real EHR input will more closely align with the characteristics of the relevant cohort. This work shows that synthetic EHR data will have practical value to the Veterans' health research community for the foreseeable future.
RESUMO
BACKGROUND: In a high-throughput environment, to PCR amplify and sequence a large set of viral isolates from populations that are potentially heterogeneous and continuously evolving, the use of degenerate PCR primers is an important strategy. Degenerate primers allow for the PCR amplification of a wider range of viral isolates with only one set of pre-mixed primers, thus increasing amplification success rates and minimizing the necessity for genome finishing activities. To successfully select a large set of degenerate PCR primers necessary to tile across an entire viral genome and maximize their success, this process is best performed computationally. RESULTS: We have developed a fully automated degenerate PCR primer design system that plays a key role in the J. Craig Venter Institute's (JCVI) high-throughput viral sequencing pipeline. A consensus viral genome, or a set of consensus segment sequences in the case of a segmented virus, is specified using IUPAC ambiguity codes in the consensus template sequence to represent the allelic diversity of the target population. PCR primer pairs are then selected computationally to produce a minimal amplicon set capable of tiling across the full length of the specified target region. As part of the tiling process, primer pairs are computationally screened to meet the criteria for successful PCR with one of two described amplification protocols. The actual sequencing success rates for designed primers for measles virus, mumps virus, human parainfluenza virus 1 and 3, human respiratory syncytial virus A and B and human metapneumovirus are described, where >90% of designed primer pairs were able to consistently successfully amplify >75% of the isolates. CONCLUSIONS: Augmenting our previously developed and published JCVI Primer Design Pipeline, we achieved similarly high sequencing success rates with only minor software modifications. The recommended methodology for the construction of the consensus sequence that encapsulates the allelic variation of the targeted population and is a key step prior to designing degenerate primers is also formally described.
Assuntos
Primers do DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Vírus/genética , Genoma Viral , Humanos , Reação em Cadeia da Polimerase , Vírus/isolamento & purificaçãoRESUMO
Gut dysbiosis is commonly observed in patients with cirrhosis and chronic gastrointestinal disorders; however, its effect on antitumor immunity in the liver is largely unknown. Here we studied how the gut microbiome affects antitumor immunity in cholangiocarcinoma. Primary sclerosing cholangitis (PSC) or colitis, two known risk factors for cholangiocarcinoma which promote tumor development in mice, caused an accumulation of CXCR2+ polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC). A decrease in gut barrier function observed in mice with PSC and colitis allowed gut-derived bacteria and lipopolysaccharide to appear in the liver and induced CXCL1 expression in hepatocytes through a TLR4-dependent mechanism and an accumulation of CXCR2+ PMN-MDSCs. In contrast, neomycin treatment blocked CXCL1 expression and PMN-MDSC accumulation and inhibited tumor growth even in the absence of liver disease or colitis. Our study demonstrates that the gut microbiome controls hepatocytes to form an immunosuppressive environment by increasing PMN-MDSCs to promote liver cancer. SIGNIFICANCE: MDSCs have been shown to be induced by tumors and suppress antitumor immunity. Here we show that the gut microbiome can control accumulation of MDSCs in the liver in the context of a benign liver disease or colitis.See related commentary by Chagani and Kwong, p. 1014.This article is highlighted in the In This Issue feature, p. 995.
Assuntos
Colangiocarcinoma/patologia , Bactérias Gram-Negativas/fisiologia , Hepatócitos/fisiologia , Neoplasias Hepáticas/patologia , Células Supressoras Mieloides/fisiologia , Animais , Modelos Animais de Doenças , Microbioma Gastrointestinal , Humanos , CamundongosRESUMO
The physiological homeostasis of gut mucosal barrier is maintained by both genetic and environmental factors and its impairment leads to pathogenesis such as inflammatory bowel disease. A cytokine like molecule, FAM3D (mouse Fam3D), is highly expressed in mouse gastrointestinal tract. Here, we demonstrate that deficiency in Fam3D is associated with impaired integrity of colonic mucosa, increased epithelial hyper-proliferation, reduced anti-microbial peptide production and increased sensitivity to chemically induced colitis associated with high incidence of cancer. Pretreatment of Fam3D-/- mice with antibiotics significantly reduces the severity of chemically induced colitis and wild type (WT) mice co-housed with Fam3D-/- mice phenocopy Fam3D-deficiency showing increased sensitivity to colitis and skewed composition of fecal microbiota. An initial equilibrium of microbiota in cohoused WT and Fam3D-/- mice is followed by an increasing divergence of the bacterial composition after separation. These results demonstrate the essential role of Fam3D in colon homeostasis, protection against inflammation associated cancer and normal microbiota composition.
Assuntos
Carcinogênese , Colo , Citocinas/metabolismo , Animais , Colite , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Neoplasias Colorretais , Modelos Animais de Doenças , Microbioma Gastrointestinal , Inflamação , Doenças Inflamatórias Intestinais , Mucosa Intestinal/crescimento & desenvolvimento , Mucosa Intestinal/patologia , Camundongos , Proteínas Citotóxicas Formadoras de Poros/metabolismoRESUMO
Aerococcus urinae (Au) and Globicatella sanguinis (Gs) are gram-positive bacteria belonging to the family Aerococcaceae and colonize the human immunocompromised and catheterized urinary tract. We identified both pathogens in polymicrobial urethral catheter biofilms (CBs) with a combination of 16S rDNA sequencing, proteomic analyses, and microbial cultures. Longitudinal sampling of biofilms from serially replaced catheters revealed that each species persisted in the urinary tract of a patient in cohabitation with 1 or more gram-negative uropathogens. The Gs and Au proteomes revealed active glycolytic, heterolactic fermentation, and peptide catabolic energy metabolism pathways in an anaerobic milieu. A few phosphotransferase system (PTS)-based sugar uptake and oligopeptide ABC transport systems were highly expressed, indicating adaptations to the supply of nutrients in urine and from exfoliating squamous epithelial and urothelial cells. Differences in the Au vs Gs metabolisms pertained to citrate lyase and utilization and storage of glycogen (evident only in Gs proteomes) and to the enzyme Xfp that degrades d-xylulose-5'-phosphate and the biosynthetic pathways for 2 protein cofactors, pyridoxal 6'-phosphate and 4'-phosphopantothenate (expressed only in Au proteomes). A predicted ZnuA-like transition metal ion uptake system was identified for Gs while Au expressed 2 LPXTG-anchored surface proteins, one of which had a predicted pilin D adhesion motif. While these proteins may contribute to fitness and virulence in the human host, it cannot be ruled out that Au and Gs fill a niche in polymicrobial biofilms without being the direct cause of injury in urothelial tissues.
RESUMO
Despite studies indicating the effects of IL-21 signaling in intestinal inflammation, its roles in intestinal homeostasis and infection are not yet clear. Here, we report potent effects of commensal microbiota on the phenotypic manifestations of IL-21 receptor deficiency. IL-21 is produced highly in the small intestine and appears to be critical for mounting an IgA response against atypical commensals such as segmented filamentous bacteria and Helicobacter, but not to the majority of commensals. In the presence of these atypical commensals, IL-21R-deficient mice exhibit reduced numbers of germinal center and IgA+ B cells and expression of activation-induced cytidine deaminase in Peyer's patches as well as a significant decrease in small intestine IgA+ plasmablasts and plasma cells, leading to higher bacterial burdens and subsequent expansion of Th17 and Treg cells. These microbiota-mediated secondary changes in turn enhance T cell responses to an oral antigen and strikingly dampen Citrobacter rodentium-induced immunopathology, demonstrating a complex interplay between IL-21-mediated mucosal immunity, microbiota, and pathogens.
Assuntos
Formas Bacterianas Atípicas/fisiologia , Linfócitos B/fisiologia , Citrobacter rodentium/fisiologia , Infecções por Enterobacteriaceae/imunologia , Helicobacter/fisiologia , Imunoglobulina A/metabolismo , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Receptores de Interleucina-21/genética , Animais , Carga Bacteriana , Diferenciação Celular , Células Cultivadas , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Homeostase , Humanos , Imunidade Humoral , Imunidade nas Mucosas , Mucosa Intestinal/microbiologia , Intestino Delgado/microbiologia , Camundongos , Camundongos Knockout , Receptores de Interleucina-21/metabolismo , Linfócitos T Reguladores/imunologia , Células Th17/imunologiaRESUMO
The factors that determine host susceptibility to tuberculosis (TB) are poorly defined. The microbiota has been identified as a key influence on the nutritional, metabolic, and immunological status of the host, although its role in the pathogenesis of TB is currently unclear. Here, we investigated the influence of Mycobacterium tuberculosis exposure on the microbiome and conversely the impact of the intestinal microbiome on the outcome of M. tuberculosis exposure in a rhesus macaque model of tuberculosis. Animals were infected with different strains and doses of M. tuberculosis in three independent experiments, resulting in a range of disease severities. The compositions of the microbiotas were then assessed using a combination of 16S rRNA and metagenomic sequencing in fecal samples collected pre- and postinfection. Clustering analyses of the microbiota compositions revealed that alterations in the microbiome after M. tuberculosis infection were of much lower magnitude than the variability seen between individual monkeys. However, the microbiomes of macaques that developed severe disease were noticeably distinct from those of the animals with less severe disease as well as from each other. In particular, the bacterial families Lachnospiraceae and Clostridiaceae were enriched in monkeys that were more susceptible to infection, while numbers of Streptococcaceae were decreased. These findings in infected nonhuman primates reveal that certain baseline microbiome communities may strongly associate with the development of severe tuberculosis following infection and can be more important disease correlates than alterations to the microbiota following M. tuberculosis infection itself.IMPORTANCE Why some but not all individuals infected with Mycobacterium tuberculosis develop disease is poorly understood. Previous studies have revealed an important influence of the microbiota on host resistance to infection with a number of different disease agents. Here, we investigated the possible role of the individual's microbiome in impacting the outcome of M. tuberculosis infection in rhesus monkeys experimentally exposed to this important human pathogen. Although M. tuberculosis infection itself caused only minor alterations in the composition of the gut microbiota in these animals, we observed a significant correlation between an individual monkey's microbiome and the severity of pulmonary disease. More importantly, this correlation between microbiota structure and disease outcome was evident even prior to infection. Taken together, our findings suggest that the composition of the microbiome may be a useful predictor of tuberculosis progression in infected individuals either directly because of the microbiome's direct influence on host resistance or indirectly because of its association with other host factors that have this influence. This calls for exploration of the potential of the microbiota composition as a predictive biomarker through carefully designed prospective studies.
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Suscetibilidade a Doenças/microbiologia , Microbioma Gastrointestinal , Tuberculose/microbiologia , Animais , Disbiose/microbiologia , Feminino , Macaca mulatta/microbiologia , Masculino , Metagenômica , Mycobacterium tuberculosis/patogenicidade , Estudos Prospectivos , RNA Ribossômico 16S/genéticaRESUMO
It is unknown whether the gut microbiome affects HIV transmission. In our recent SHIV vaccine study, we found that the naive rhesus macaques from two different sources had significantly different rates of infection against repeated low-dose intrarectal challenge with SHIVSF162P4 virus. Exploring causes, we found that the more susceptible group of seven macaques had significantly more activated CD4+CCR5+Ki67+ T cells in the rectal mucosa than the more resistant group of 11 macaques from a different source. The prevalence of pre-challenge activated rectal CD4 T cells in the naive macaques correlated inversely with the number of challenges required to infect. Because the two naive groups came from different sources, we hypothesized that their microbiomes may differ and might explain the activation difference. Indeed, after sequencing 16s rRNA, we found differences between the two naive groups that correlated with immune activation status. Distinct gut microbiota induced different levels of immune activation ex vivo. Significantly lower ratios of Bacteroides to Prevotella, and significantly lower levels of Firmicutes were found in the susceptible cohort, which were also inversely correlated with high levels of immune activation in the rectal mucosa. Thus, host-microbiome interactions might influence HIV/SIV mucosal transmission through effects on mucosal immune activation.
Assuntos
Bacteroides/fisiologia , Linfócitos T CD4-Positivos/imunologia , Firmicutes/fisiologia , Microbioma Gastrointestinal/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Mucosa Intestinal/imunologia , Prevotella/fisiologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/fisiologia , Animais , Suscetibilidade a Doenças , Infecções por HIV/microbiologia , Humanos , Mucosa Intestinal/microbiologia , Antígeno Ki-67/metabolismo , Ativação Linfocitária , Macaca , RNA Ribossômico 16S/análise , Receptores CCR5/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/microbiologiaRESUMO
Primary liver tumors and liver metastasis currently represent the leading cause of cancer-related death. Commensal bacteria are important regulators of antitumor immunity, and although the liver is exposed to gut bacteria, their role in antitumor surveillance of liver tumors is poorly understood. We found that altering commensal gut bacteria in mice induced a liver-selective antitumor effect, with an increase of hepatic CXCR6+ natural killer T (NKT) cells and heightened interferon-γ production upon antigen stimulation. In vivo functional studies showed that NKT cells mediated liver-selective tumor inhibition. NKT cell accumulation was regulated by CXCL16 expression of liver sinusoidal endothelial cells, which was controlled by gut microbiome-mediated primary-to-secondary bile acid conversion. Our study suggests a link between gut bacteria-controlled bile acid metabolism and liver antitumor immunosurveillance.
Assuntos
Ácidos e Sais Biliares/metabolismo , Microbioma Gastrointestinal/imunologia , Vigilância Imunológica , Neoplasias Hepáticas/imunologia , Fígado/metabolismo , Células T Matadoras Naturais/imunologia , Animais , Quimiocina CXCL16/metabolismo , Clostridium/metabolismo , Humanos , Fígado/imunologia , Fígado/patologia , Neoplasias Hepáticas/patologia , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Receptores CXCR6/metabolismoRESUMO
BACKGROUND: Effective treatment of Mycobacterium tuberculosis (Mtb) infection requires at least 6 months of daily therapy with multiple orally administered antibiotics. Although this drug regimen is administered annually to millions worldwide, the impact of such intensive antimicrobial treatment on the host microbiome has never been formally investigated. Here, we characterized the longitudinal outcome of conventional isoniazid-rifampin-pyrazinamide (HRZ) TB drug administration on the diversity and composition of the intestinal microbiota in Mtb-infected mice by means of 16S rRNA sequencing. We also investigated the effects of each of the individual antibiotics alone and in different combinations. RESULTS: While inducing only a transient decrease in microbial diversity, HRZ treatment triggered a marked, immediate and reproducible alteration in community structure that persisted for the entire course of therapy and for at least 3 months following its cessation. Members of order Clostridiales were among the taxa that decreased in relative frequencies during treatment and family Porphyromonadaceae significantly increased post treatment. Experiments comparing monotherapy and different combination therapies identified rifampin as the major driver of the observed alterations induced by the HRZ cocktail but also revealed unexpected effects of isoniazid and pyrazinamide in certain drug pairings. CONCLUSIONS: This report provides the first detailed analysis of the longitudinal changes in the intestinal microbiota due to anti-tuberculosis therapy. Importantly, many of the affected taxa have been previously shown in other systems to be associated with modifications in immunologic function. Together, our findings reveal that the antibiotics used in conventional TB treatment induce a distinct and long lasting dysbiosis. In addition, they establish a murine model for studying the potential impact of this dysbiosis on host resistance and physiology.
Assuntos
Antituberculosos/efeitos adversos , Disbiose/etiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/patologia , Isoniazida/efeitos adversos , Pirazinamida/efeitos adversos , Rifampina/efeitos adversos , Animais , Antituberculosos/administração & dosagem , Antituberculosos/uso terapêutico , Clostridiales/genética , Clostridiales/isolamento & purificação , Combinação de Medicamentos , Microbioma Gastrointestinal/genética , Intestinos/microbiologia , Isoniazida/administração & dosagem , Isoniazida/uso terapêutico , Camundongos , Mycobacterium tuberculosis/efeitos dos fármacos , Porphyromonas/genética , Porphyromonas/isolamento & purificação , Pirazinamida/administração & dosagem , Pirazinamida/uso terapêutico , RNA Ribossômico 16S , Rifampina/administração & dosagem , Rifampina/uso terapêutico , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologiaRESUMO
While insulin replacement therapy restores the health and prevents the onset of diabetic complications (DC) for many decades, some T1D patients have elevated hemoglobin A1c values suggesting poor glycemic control, a risk factor of DC. We surveyed the stool microbiome and urinary proteome of a cohort of 220 adolescents and children, half of which had lived with T1D for an average of 7 years and half of which were healthy siblings. Phylogenetic analysis of the 16S rRNA gene did not reveal significant differences in gut microbial alpha-diversity comparing the two cohorts. The urinary proteome of T1D patients revealed increased abundances of several lysosomal proteins that correlated with elevated HbA1c values. In silico protein network analysis linked such proteins to extracellular matrix components and the glycoprotein LRG1. LRG1 is a prominent inflammation and neovascularization biomarker. We hypothesize that these changes implicate aberrant glycation of macromolecules that alter lysosomal function and metabolism in renal tubular epithelial cells, cells that line part of the upper urinary tract.