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1.
Anal Bioanal Chem ; 416(7): 1745-1757, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38324070

RESUMO

Mass spectrometry (MS) and MS imaging (MSI) are used extensively for both the spatial and bulk characterization of samples in lipidomics and proteomics workflows. These datasets are typically generated independently due to different requirements for sample preparation. However, modern omics technologies now provide higher sample throughput and deeper molecular coverage, which, in combination with more sophisticated bioinformatic and statistical pipelines, make generating multiomics data from a single sample a reality. In this workflow, we use spatial lipidomics data generated by matrix-assisted laser desorption/ionization MSI (MALDI-MSI) on prostate cancer (PCa) radical prostatectomy cores to guide the definition of tumor and benign tissue regions for laser capture microdissection (LCM) and bottom-up proteomics all on the same sample and using the same mass spectrometer. Accurate region of interest (ROI) mapping was facilitated by the SCiLS region mapper software and dissected regions were analyzed using a dia-PASEF workflow. A total of 5525 unique protein groups were identified from all dissected regions. Lysophosphatidylcholine acyltransferase 1 (LPCAT1), a lipid remodelling enzyme, was significantly enriched in the dissected regions of cancerous epithelium (CE) compared to benign epithelium (BE). The increased abundance of this protein was reflected in the lipidomics data with an increased ion intensity ratio for pairs of phosphatidylcholines (PC) and lysophosphatidylcholines (LPC) in CE compared to BE.


Assuntos
Multiômica , Neoplasias da Próstata , Masculino , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Microdissecção e Captura a Laser , Fosfatidilcolinas/metabolismo
2.
Br J Cancer ; 130(5): 741-754, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38216720

RESUMO

BACKGROUND: Peroxisomes are central metabolic organelles that have key roles in fatty acid homoeostasis. As prostate cancer (PCa) is particularly reliant on fatty acid metabolism, we explored the contribution of peroxisomal ß-oxidation (perFAO) to PCa viability and therapy response. METHODS: Bioinformatic analysis was performed on clinical transcriptomic datasets to identify the perFAO enzyme, 2,4-dienoyl CoA reductase 2 (DECR2) as a target gene of interest. Impact of DECR2 and perFAO inhibition via thioridazine was examined in vitro, in vivo, and in clinical prostate tumours cultured ex vivo. Transcriptomic and lipidomic profiling was used to determine the functional consequences of DECR2 inhibition in PCa. RESULTS: DECR2 is upregulated in clinical PCa, most notably in metastatic castrate-resistant PCa (CRPC). Depletion of DECR2 significantly suppressed proliferation, migration, and 3D growth of a range of CRPC and therapy-resistant PCa cell lines, and inhibited LNCaP tumour growth and proliferation in vivo. DECR2 influences cell cycle progression and lipid metabolism to support tumour cell proliferation. Further, co-targeting of perFAO and standard-of-care androgen receptor inhibition enhanced suppression of PCa cell proliferation. CONCLUSION: Our findings support a focus on perFAO, specifically DECR2, as a promising therapeutic target for CRPC and as a novel strategy to overcome lethal treatment resistance.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Metabolismo dos Lipídeos/genética , Linhagem Celular Tumoral , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Androgênios/metabolismo , Proliferação de Células , Ácidos Graxos
3.
Biomedicines ; 11(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38137495

RESUMO

Haematopoietic stem cell transplantation (HSCT) is a curative approach for blood cancers, yet its efficacy is undermined by a range of acute and chronic complications. In light of mounting evidence to suggest that these complications are linked to a dysbiotic gut microbiome, we aimed to evaluate the feasibility of faecal microbiota transplantation (FMT) delivered during the acute phase after HSCT. Of note, this trial opted for FMT prepared using the individual's own stool (autologous FMT) to mitigate the risks of disease transmission from a donor stool. Adults (>18 years) with multiple myeloma were recruited from a single centre. The stool was collected prior to starting first line therapy. Patients who progressed to HSCT were offered FMT via 3 × retention enemas before day +5 (HSCT = day 0). The feasibility was determined by the recruitment rate, number and volume of enemas administered, and the retention time. Longitudinally collected stool samples were also collected to explore the influence of auto-FMT using 16S rRNA gene sequencing. n = 4 (2F:2M) participants received auto-FMT in 12 months. Participants received an average of 2.25 (1-3) enemas 43.67 (25-50) mL total, retained for an average of 60.78 (10-145) min. No adverse events (AEs) attributed to the FMT were identified. Although the minimum requirements were met for the volume and retention of auto-FMT, the recruitment was significantly impacted by the logistical challenges of the pretherapy stool collection. This ultimately undermined the feasibility of this trial and suggests that third party (donor) FMT should be prioritised.

4.
Science ; 381(6658): 682-686, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37561843

RESUMO

Synthetic biology has developed sophisticated cellular biosensors to detect and respond to human disease. However, biosensors have not yet been engineered to detect specific extracellular DNA sequences and mutations. Here, we engineered naturally competent Acinetobacter baylyi to detect donor DNA from the genomes of colorectal cancer (CRC) cells, organoids, and tumors. We characterized the functionality of the biosensors in vitro with coculture assays and then validated them in vivo with sensor bacteria delivered to mice harboring colorectal tumors. We observed horizontal gene transfer from the tumor to the sensor bacteria in our mouse model of CRC. This cellular assay for targeted, CRISPR-discriminated horizontal gene transfer (CATCH) enables the biodetection of specific cell-free DNA.


Assuntos
Acinetobacter , Técnicas Biossensoriais , Ácidos Nucleicos Livres , Neoplasias Colorretais , DNA de Neoplasias , Animais , Humanos , Camundongos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , DNA de Neoplasias/análise , Mutação , Acinetobacter/genética , Ácidos Nucleicos Livres/análise , Bioengenharia
6.
Cell Rep Med ; 4(3): 100971, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36871558

RESUMO

Identifying the molecular mechanisms that promote optimal immune responses to coronavirus disease 2019 (COVID-19) vaccination is critical for future rational vaccine design. Here, we longitudinally profile innate and adaptive immune responses in 102 adults after the first, second, and third doses of mRNA or adenovirus-vectored COVID-19 vaccines. Using a multi-omics approach, we identify key differences in the immune responses induced by ChAdOx1-S and BNT162b2 that correlate with antigen-specific antibody and T cell responses or vaccine reactogenicity. Unexpectedly, we observe that vaccination with ChAdOx1-S, but not BNT162b2, induces an adenoviral vector-specific memory response after the first dose, which correlates with the expression of proteins with roles in thrombosis with potential implications for thrombosis with thrombocytopenia syndrome (TTS), a rare but serious adverse event linked to adenovirus-vectored vaccines. The COVID-19 Vaccine Immune Responses Study thus represents a major resource that can be used to understand the immunogenicity and reactogenicity of these COVID-19 vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Vacinas , Adulto , Humanos , Adenoviridae/genética , Anticorpos , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , RNA Mensageiro/genética
7.
Commun Biol ; 6(1): 221, 2023 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-36841913

RESUMO

Viruses are increasingly recognised as important components of the human microbiome, fulfilling numerous ecological roles including bacterial predation, immune stimulation, genetic diversification, horizontal gene transfer, microbial interactions, and augmentation of metabolic functions. However, our current view of the human gut virome is tainted by previous sequencing requirements that necessitated the amplification of starting nucleic acids. In this study, we performed an original longitudinal analysis of 40 healthy control, 19 Crohn's disease, and 20 ulcerative colitis viromes over three time points without an amplification bias, which revealed and highlighted the interpersonal individuality of the human gut virome. In contrast to a 16 S rRNA gene analysis of matched samples, we show that α- and ß-diversity metrics of unamplified viromes are not as efficient at discerning controls from patients with inflammatory bowel disease. Additionally, we explored the intrinsic properties of unamplified gut viromes and show there is considerable interpersonal variability in viral taxa, infrequent longitudinal persistence of intrapersonal viruses, and vast fluctuations in the abundance of temporal viruses. Together, these properties of unamplified faecal viromes confound the ability to discern disease associations but significantly advance toward an unbiased and accurate representation of the human gut virome.


Assuntos
Colite Ulcerativa , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Vírus , Humanos , Viroma/genética , Microbioma Gastrointestinal/genética , Vírus/genética , Colite Ulcerativa/genética , Colite Ulcerativa/microbiologia , Doenças Inflamatórias Intestinais/genética
8.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834715

RESUMO

The interaction between leukocytes and cytokine-activated retinal endothelium is an initiating step in non-infectious uveitis involving the posterior eye, mediated by cell adhesion molecules. However, because cell adhesion molecules are required for immune surveillance, therapeutic interventions would ideally be employed indirectly. Using 28 primary human retinal endothelial cell isolates, this study sought to identify transcription factor targets for reducing levels of the key retinal endothelial cell adhesion molecule, intercellular adhesion molecule (ICAM)-1, and limiting leukocyte binding to the retinal endothelium. Five candidate transcription factors-C2CD4B, EGR3, FOSB, IRF1, and JUNB-were identified by differential expression analysis of a transcriptome generated from IL-1ß- or TNF-α-stimulated human retinal endothelial cells, interpreted in the context of the published literature. Further filtering involved molecular studies: of the five candidates, C2CD4B and IRF1 consistently demonstrated extended induction in IL-1ß- or TNF-α-activated retinal endothelial cells and demonstrated a significant decrease in both ICAM-1 transcript and ICAM-1 membrane-bound protein expression by cytokine-activated retinal endothelial cells following treatment with small interfering RNA. RNA interference of C2CD4B or IRF1 significantly reduced leukocyte binding in a majority of human retinal endothelial cell isolates stimulated by IL-1ß or TNF-α. Our observations suggest that the transcription factors C2CD4B and IRF1 may be potential drug targets for limiting leukocyte-retinal endothelial cell interactions in non-infectious uveitis involving the posterior eye.


Assuntos
Células Endoteliais , Molécula 1 de Adesão Intercelular , Humanos , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Citocinas/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos/metabolismo , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
9.
Transl Vis Sci Technol ; 11(8): 27, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36018584

RESUMO

Purpose: Molecular profiling of human retinal endothelial cells provides opportunities to understand the roles of this cell population in maintenance of the blood-ocular barrier, and its involvements in diverse retinal vasculopathies. We aimed to generate a transcriptome of human retinal endothelial cells in the unstimulated state, and following treatment with inflammatory cytokines linked to cell dysfunction. Methods: Endothelial cells were isolated from retinae of five human cadaveric donors, and treated for 60 minutes and 24 hours with interleukin-1ß or tumor necrosis factor-α, or exposed to medium alone for the same intervals. Expression of intercellular adhesion molecule-1 was measured by RT-qPCR to confirm cytokine-induced activation of the cells. RNA was sequenced on the Illumina NovaSeq 6000 platform. Reads were aligned to the human GRCh38 genome, and reads that aligned to Ensembl-annotated genes were counted. Quality control of sequencing was performed with FastQC, and sequences were classified by Kraken. Results: A human retinal endothelial cell RNA-sequencing dataset with mean of 99% reads aligned to the human genome was produced as raw RNA sequence data (FASTQ files) and processed read data (XLSX files). Multidimensional scaling analysis showed a strong donor effect, which was readily controlled by ComBat. Conclusions: Our dataset may be useful for human retinal endothelial cell transcriptomic assemblies, functional gene annotating and/or gene expression and enrichment analyses, as well as cross-dataset harmonization. Translational Relevance: The molecular profile of the human retinal endothelium is a source of candidate biologic targets for retinal vasculopathies.


Assuntos
Células Endoteliais , Transcriptoma , Citocinas , Humanos , RNA , Retina
10.
STAR Protoc ; 3(1): 101220, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35284839

RESUMO

We present this protocol using a mouse model to assess the impact of early-life antibiotic exposure on mammalian lifespan and the composition of the gut microbiota over time. We describe longitudinal fecal sampling and health monitoring following early-life antibiotic exposure. We detail DNA extraction and 16S rRNA gene sequencing to longitudinally profile the composition of the fecal microbiota. Finally, we discuss how to address potential confounders such as the stochastic recolonization of the gut microbiota following antibiotic exposure. For complete details on the use and execution of this protocol, please refer to Lynn et al. (2021).


Assuntos
Antibacterianos , Microbioma Gastrointestinal , Animais , Antibacterianos/efeitos adversos , Fezes , Microbioma Gastrointestinal/genética , Longevidade , Mamíferos/genética , Camundongos , RNA Ribossômico 16S/genética
11.
BMC Med ; 20(1): 26, 2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35027067

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly infectious respiratory virus which is responsible for the coronavirus disease 2019 (COVID-19) pandemic. It is increasingly clear that recovered individuals, even those who had mild COVID-19, can suffer from persistent symptoms for many months after infection, a condition referred to as "long COVID", post-acute sequelae of COVID-19 (PASC), post-acute COVID-19 syndrome, or post COVID-19 condition. However, despite the plethora of research on COVID-19, relatively little is known about the molecular underpinnings of these long-term effects. METHODS: We have undertaken an integrated analysis of immune responses in blood at a transcriptional, cellular, and serological level at 12, 16, and 24 weeks post-infection (wpi) in 69 patients recovering from mild, moderate, severe, or critical COVID-19 in comparison to healthy uninfected controls. Twenty-one of these patients were referred to a long COVID clinic and > 50% reported ongoing symptoms more than 6 months post-infection. RESULTS: Anti-Spike and anti-RBD IgG responses were largely stable up to 24 wpi and correlated with disease severity. Deep immunophenotyping revealed significant differences in multiple innate (NK cells, LD neutrophils, CXCR3+ monocytes) and adaptive immune populations (T helper, T follicular helper, and regulatory T cells) in convalescent individuals compared to healthy controls, which were most strongly evident at 12 and 16 wpi. RNA sequencing revealed significant perturbations to gene expression in COVID-19 convalescents until at least 6 months post-infection. We also uncovered significant differences in the transcriptome at 24 wpi of convalescents who were referred to a long COVID clinic compared to those who were not. CONCLUSIONS: Variation in the rate of recovery from infection at a cellular and transcriptional level may explain the persistence of symptoms associated with long COVID in some individuals.


Assuntos
COVID-19 , Anticorpos Antivirais , COVID-19/complicações , Humanos , Sistema Imunitário , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
12.
STAR Protoc ; 3(4): 101914, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36595955

RESUMO

Understanding how changes in gut microbiota in early life impact immune programming can be difficult to study due to variations in the assembly of the microbiota. In this protocol, we describe how to colonize gnotobiotic/germ-free mice in early life with different microbiota community types (e.g., PAMI and PAMII). We detail several assays to determine whether differential colonization alters immune programming in early life. We also describe how to propagate mouse fecal microbiota transplant material if the donor fecal sample is limited. For complete details on the use and execution of this protocol, please refer to Lynn et al. (2021).1.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Camundongos , Transplante de Microbiota Fecal , Vida Livre de Germes , Fezes
13.
Vaccine ; 40(11): 1594-1605, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33895015

RESUMO

In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.


Assuntos
Difteria , Vacinas Anti-Haemophilus , Tétano , Coqueluche , Animais , Anticorpos Antibacterianos , Vacina BCG , Difteria/prevenção & controle , Vacina contra Difteria, Tétano e Coqueluche , Feminino , Imunização , Camundongos , Tétano/prevenção & controle , Vacinação , Coqueluche/prevenção & controle
14.
Cell Rep ; 36(8): 109564, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34433065

RESUMO

Studies investigating whether there is a causative link between the gut microbiota and lifespan have largely been restricted to invertebrates or to mice with a reduced lifespan because of a genetic deficiency. We investigate the effect of early-life antibiotic exposure on otherwise healthy, normal chow-fed, wild-type mice, monitoring these mice for more than 700 days in comparison with untreated control mice. We demonstrate the emergence of two different low-diversity community types, post-antibiotic microbiota (PAM) I and PAM II, following antibiotic exposure. PAM II but not PAM I mice have impaired immunity, increased insulin resistance, and evidence of increased inflammaging in later life as well as a reduced lifespan. Our data suggest that differences in the composition of the gut microbiota following antibiotic exposure differentially affect host health and longevity in later life.


Assuntos
Antibacterianos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/imunologia , Longevidade/imunologia , Animais , Longevidade/efeitos dos fármacos , Camundongos
15.
Front Immunol ; 12: 644153, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968035

RESUMO

During recent Zika epidemics, adults infected with Zika virus (ZIKV) have developed organ-specific inflammatory complications. The most serious Zika-associated inflammatory eye disease is uveitis, which is commonly anterior in type, affecting both eyes and responding to corticosteroid eye drops. Mechanisms of Zika-associated anterior uveitis are unknown, but ZIKV has been identified in the aqueous humor of affected individuals. The iris pigment epithelium is a target cell population in viral anterior uveitis, and it acts to maintain immune privilege within the anterior eye. Interactions between ZIKV and human iris pigment epithelial cells were investigated with infectivity assays and RNA-sequencing. Primary cell isolates were prepared from eyes of 20 cadaveric donors, and infected for 24 hours with PRVABC59 strain ZIKV or incubated uninfected as control. Cytoimmunofluorescence, RT-qPCR on total cellular RNA, and focus-forming assays of culture supernatant showed cell isolates were permissive to infection, and supported replication and release of infectious ZIKV. To explore molecular responses of cell isolates to ZIKV infection at the whole transcriptome level, RNA was sequenced on the Illumina NextSeq 500 platform, and results were aligned to the human GRCh38 genome. Multidimensional scaling showed clear separation between transcriptomes of infected and uninfected cell isolates. Differential expression analysis indicated a vigorous molecular response of the cell to ZIKV: 7,935 genes were differentially expressed between ZIKV-infected and uninfected cells (FDR < 0.05), and 99% of 613 genes that changed at least two-fold were up-regulated. Reactome and KEGG pathway and Gene Ontology enrichment analyses indicated strong activation of viral recognition and defense, in addition to biosynthesis processes. A CHAT network included 6275 molecular nodes and 24 contextual hubs in the cell response to ZIKV infection. Receptor-interacting serine/threonine kinase 1 (RIPK1) was the most significantly connected contextual hub. Correlation of gene expression with read counts assigned to the ZIKV genome identified a negative correlation between interferon signaling and viral load across isolates. This work represents the first investigation of mechanisms of Zika-associated anterior uveitis using an in vitro human cell model. The results suggest the iris pigment epithelium mounts a molecular response that limits intraocular pathology in most individuals.


Assuntos
Células Epiteliais , Regulação Viral da Expressão Gênica/imunologia , Epitélio Pigmentado Ocular , RNA Viral/imunologia , Infecção por Zika virus , Zika virus/imunologia , Células Cultivadas , Células Epiteliais/imunologia , Células Epiteliais/patologia , Células Epiteliais/virologia , Genoma Viral/imunologia , Humanos , Iris/imunologia , Iris/patologia , Iris/virologia , Epitélio Pigmentado Ocular/imunologia , Epitélio Pigmentado Ocular/patologia , Epitélio Pigmentado Ocular/virologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/patologia
16.
Appl Environ Microbiol ; 87(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33579683

RESUMO

The gut microbiota has a significant impact on host health. Dietary interventions using probiotics, prebiotics and postbiotics have the potential to alter microbiota composition and function. Other therapeutic interventions such as antibiotics and faecal microbiota transplantation have also been shown to significantly alter the microbiota and its metabolites. Supplementation of a faecal fermentation model of the human gut with a postbiotic product Lactobacillus LB led to changes in microbiome composition (i.e. increase in beneficial bifidobacteria) and associated metabolic changes (i.e. increased acid production). Lactobacillus LB is a heat-treated preparation of cellular biomass and a fermentate generated by Limosilactobacillus fermentum CNCM MA65/4E-1b (formerly known as Lactobacillus fermentum CNCM MA65/4E-1b) and Lactobacillus delbrueckii ssp. delbrueckii CNCM MA65/4E-2z, medically relevant strains used to produce antidiarrheal preparations. In pure culture, Lactobacillus LB also stimulates the growth of a range of bifidobacterial species and strains. Lactobacillus LB-like preparations generated using other Lactobacillaceae, including commercially available probiotic bacteria, did not have the same impact on a model strain (Bifidobacterium longum subsp. infantis ATCC 15697). This bifidogenic activity is heat- and enzyme-stable and cannot be attributed to lactose, which is a major constituent of Lactobacillus LB. L fermentum CNCM MA65/4E-1b is largely responsible for the observed activity and there is a clear role for compounds smaller than 1 kDa.Importance In general, disruptions to the gut microbiota are associated with multiple disorders in humans. The presence of high levels of Bifidobacterium spp. in the human gut is commonly considered to be beneficial. Bifidobacteria can be supplemented in the diet (as probiotics) or those bifidobacteria already present in the gut can be stimulated by the consumption of prebiotics such as inulin. We demonstrate that Lactobacillus LB (a product consisting of two heat-killed lactic acid bacteria and their metabolites) can stimulate the growth of bifidobacteria in human fermented faecal communities and in pure culture. Given the heat-treatment applied during the production process, there is no risk of the lactic acid bacteria colonising (or causing bacteraemia) in vulnerable consumers (infants, immunocompromised, etc). Lactobacillus LB has the potential to affect human health by selectively promoting the growth of beneficial bacteria.

17.
Cell Rep Med ; 2(12): 100464, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-35028606

RESUMO

Immune agonist antibodies (IAAs) are promising immunotherapies that target co-stimulatory receptors to induce potent anti-tumor immune responses, particularly when combined with checkpoint inhibitors. Unfortunately, their clinical translation is hampered by serious dose-limiting, immune-mediated toxicities, including high-grade and sometimes fatal liver damage, cytokine release syndrome (CRS), and colitis. We show that the immunotoxicity, induced by the IAAs anti-CD40 and anti-CD137, is dependent on the gut microbiota. Germ-free or antibiotic-treated mice have significantly reduced colitis, CRS, and liver damage following IAA treatment compared with conventional mice or germ-free mice recolonized via fecal microbiota transplant. MyD88 signaling is required for IAA-induced CRS and for anti-CD137-induced, but not anti-CD40-induced, liver damage. Importantly, antibiotic treatment does not impair IAA anti-tumor efficacy, alone or in combination with anti-PD1. Our results suggest that microbiota-targeted therapies could overcome the toxicity induced by IAAs without impairing their anti-tumor activity.


Assuntos
Antineoplásicos/farmacologia , Antígenos CD40/imunologia , Microbioma Gastrointestinal , Imunoterapia/efeitos adversos , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Antibacterianos/farmacologia , Ácidos e Sais Biliares/metabolismo , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/patologia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal/efeitos dos fármacos , Vida Livre de Germes , Inflamação/patologia , Interferon Tipo I/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
18.
Gut ; 70(3): 499-510, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32536605

RESUMO

OBJECTIVE: The microbiome contributes to the pathogenesis of inflammatory bowel disease (IBD) but the relative contribution of different lifestyle and environmental factors to the compositional variability of the gut microbiota is unclear. DESIGN: Here, we rank the size effect of disease activity, medications, diet and geographic location of the faecal microbiota composition (16S rRNA gene sequencing) in patients with Crohn's disease (CD; n=303), ulcerative colitis (UC; n = 228) and controls (n=161), followed longitudinally (at three time points with 16 weeks intervals). RESULTS: Reduced microbiota diversity but increased variability was confirmed in CD and UC compared with controls. Significant compositional differences between diseases, particularly CD, and controls were evident. Longitudinal analyses revealed reduced temporal microbiota stability in IBD, particularly in patients with changes in disease activity. Machine learning separated disease from controls, and active from inactive disease, when consecutive time points were modelled. Geographic location accounted for most of the microbiota variance, second to the presence or absence of CD, followed by history of surgical resection, alcohol consumption and UC diagnosis, medications and diet with most (90.3%) of the compositional variance stochastic or unexplained. CONCLUSION: The popular concept of precision medicine and rational design of any therapeutic manipulation of the microbiota will have to contend not only with the heterogeneity of the host response, but also with widely differing lifestyles and with much variance still unaccounted for.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/microbiologia , Estilo de Vida , Canadá , Dieta , Feminino , Geografia , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Irlanda , Estudos Longitudinais , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
19.
BMC Biol ; 18(1): 173, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33218339

RESUMO

BACKGROUND: It has become increasingly accepted that establishing and maintaining a complex and diverse gut microbiota is fundamental to human health. There are growing efforts to identify means of modulating and influencing the microbiota, especially in individuals who have experienced a disruption in their native microbiota. Faecal microbiota transplantation (FMT) is one method that restores diversity to the microbiota of an individual by introducing microbes from a healthy donor. FMT introduces the total microbial load into the recipient, including the bacteria, archaea, yeasts, protists and viruses. In this study, we investigated whether an autochthonous faecal viral transfer (FVT), in the form of a sterile faecal filtrate, could impact the recovery of a bacteriome disrupted by antibiotic treatment. RESULTS: Following antibiotic disruption of the bacteriome, test mice received an FVT harvested prior to antibiotic treatment, while control mice received a heat- and nuclease-treated FVT. In both groups of mice, the perturbed microbiome reverted over time to one more similar to the pre-treatment one. However, the bacteriomes of mice that received an FVT, in which bacteriophages predominate, separated from those of the control mice as determined by principal co-ordinate analysis (PCoA). Moreover, analysis of the differentially abundant taxa indicated a closer resemblance to the pre-treatment bacteriome in the test mice that had received an FVT. Similarly, metagenomic sequencing of the virome confirmed that faecal bacteriophages of FVT and control mice differed over time in both abundance and diversity, with the phages constituting the FVT persisting in mice that received them. CONCLUSIONS: An autochthonous virome transfer reshaped the bacteriomes of mice post-antibiotic treatment such that they more closely resembled the pre-antibiotic microbiota profile compared to mice that received non-viable phages. Thus, FVT may have a role in addressing antibiotic-associated microbiota alterations and potentially prevent the establishment of post-antibiotic infection. Given that bacteriophages are biologically inert in the absence of their host bacteria, they could form a safe and effective alternative to whole microbiota transplants that could be delivered during/following perturbation of the gut flora.


Assuntos
Antibacterianos/efeitos adversos , Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Transplante de Microbiota Fecal , Fezes/microbiologia , Metagenoma , Microbiota , Animais , Antibacterianos/administração & dosagem , Bactérias/efeitos dos fármacos , Camundongos
20.
Cell Host Microbe ; 26(6): 764-778.e5, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31757768

RESUMO

The human gut virome is thought to significantly impact the microbiome and human health. However, most virome analyses have been performed on a limited fraction of known viruses. Using whole-virome analysis on a published keystone inflammatory bowel disease (IBD) cohort and an in-house ulcerative colitis dataset, we shed light on the composition of the human gut virome in IBD beyond this identifiable minority. We observe IBD-specific changes to the virome and increased numbers of temperate phage sequences in individuals with Crohn's disease. Unlike prior database-dependent methods, no changes in viral richness were observed. Among IBD subjects, the changes in virome composition reflected alterations in bacterial composition. Furthermore, incorporating both bacteriome and virome composition offered greater classification power between health and disease. This approach to analyzing whole virome across cohorts highlights significant IBD signals, which may be crucial for developing future biomarkers and therapeutics.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/virologia , Metagenômica , Bactérias/classificação , Bactérias/genética , Bacteriófagos/classificação , Bacteriófagos/genética , Colite Ulcerativa/microbiologia , Colite Ulcerativa/virologia , Doença de Crohn/microbiologia , Doença de Crohn/virologia , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Masculino , Vírus/classificação , Vírus/genética
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