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1.
Nature ; 596(7870): 114-118, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34262174

RESUMO

Pathogenic fungi reside in the intestinal microbiota but rarely cause disease. Little is known about the interactions between fungi and the immune system that promote commensalism. Here we investigate the role of adaptive immunity in promoting mutual interactions between fungi and host. We find that potentially pathogenic Candida species induce and are targeted by intestinal immunoglobulin A (IgA) responses. Focused studies on Candida albicans reveal that the pathogenic hyphal morphotype, which is specialized for adhesion and invasion, is preferentially targeted and suppressed by intestinal IgA responses. IgA from mice and humans directly targets hyphal-enriched cell-surface adhesins. Although typically required for pathogenesis, C. albicans hyphae are less fit for gut colonization1,2 and we show that immune selection against hyphae improves the competitive fitness of C. albicans. C. albicans exacerbates intestinal colitis3 and we demonstrate that hyphae and an IgA-targeted adhesin exacerbate intestinal damage. Finally, using a clinically relevant vaccine to induce an adhesin-specific immune response protects mice from C. albicans-associated damage during colitis. Together, our findings show that adaptive immunity suppresses harmful fungal effectors, with benefits to both C. albicans and its host. Thus, IgA uniquely uncouples colonization from pathogenesis in commensal fungi to promote homeostasis.


Assuntos
Imunidade Adaptativa , Candida albicans/imunologia , Candida albicans/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Simbiose/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos de Fungos/imunologia , Candida albicans/patogenicidade , Colite/imunologia , Colite/microbiologia , Colite/patologia , Feminino , Vacinas Fúngicas/imunologia , Microbioma Gastrointestinal/imunologia , Humanos , Hifas/imunologia , Imunoglobulina A/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
2.
Am J Hum Genet ; 108(3): 431-445, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33600772

RESUMO

Whether or not populations diverge with respect to the genetic contribution to risk of specific complex diseases is relevant to understanding the evolution of susceptibility and origins of health disparities. Here, we describe a large-scale whole-genome sequencing study of inflammatory bowel disease encompassing 1,774 affected individuals and 1,644 healthy control Americans with African ancestry (African Americans). Although no new loci for inflammatory bowel disease are discovered at genome-wide significance levels, we identify numerous instances of differential effect sizes in combination with divergent allele frequencies. For example, the major effect at PTGER4 fine maps to a single credible interval of 22 SNPs corresponding to one of four independent associations at the locus in European ancestry individuals but with an elevated odds ratio for Crohn disease in African Americans. A rare variant aggregate analysis implicates Ca2+-binding neuro-immunomodulator CALB2 in ulcerative colitis. Highly significant overall overlap of common variant risk for inflammatory bowel disease susceptibility between individuals with African and European ancestries was observed, with 41 of 241 previously known lead variants replicated and overall correlations in effect sizes of 0.68 for combined inflammatory bowel disease. Nevertheless, subtle differences influence the performance of polygenic risk scores, and we show that ancestry-appropriate weights significantly improve polygenic prediction in the highest percentiles of risk. The median amount of variance explained per locus remains the same in African and European cohorts, providing evidence for compensation of effect sizes as allele frequencies diverge, as expected under a highly polygenic model of disease.


Assuntos
Calbindina 2/genética , Predisposição Genética para Doença , Doenças Inflamatórias Intestinais/genética , Receptores de Prostaglandina E Subtipo EP4/genética , Negro ou Afro-Americano/genética , Idoso , Idoso de 80 Anos ou mais , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Doença de Crohn/genética , Doença de Crohn/patologia , Feminino , Frequência do Gene , Estudo de Associação Genômica Ampla , Humanos , Doenças Inflamatórias Intestinais/patologia , Masculino , Herança Multifatorial/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Sequenciamento Completo do Genoma
3.
Artigo em Inglês | MEDLINE | ID: mdl-37743037

RESUMO

BACKGROUND & AIMS: Although biologics have revolutionized the treatment of Crohn's disease (CD), an efficacy ceiling has been reached. Combining biologic therapies may improve remission rates. METHODS: EXPLORER, a phase 4, single-arm, open-label study, evaluated triple combination therapy with vedolizumab (300 mg on day 1, weeks 2 and 6, and then every 8 weeks), adalimumab (160 mg on day 2, 80 mg at week 2, then 40 mg every 2 weeks), and methotrexate (15 mg weekly) in biologic-naïve patients with newly diagnosed, moderate- to high-risk CD. Endoscopic remission at week 26 (primary end point; Simple Endoscopic Score for CD ≤2), clinical remission at weeks 10 and 26 (secondary end point; Crohn's Disease Activity Index <150), and incidences of adverse events and serious adverse events were evaluated. RESULTS: Among 55 enrolled patients, the mean CD duration was 0.4 years, the mean baseline Simple Endoscopic Score for CD was 12.6, and the mean baseline Crohn's Disease Activity Index was 265.5. At week 26, 19 patients (34.5%) were in endoscopic remission. At weeks 10 and 26, 34 (61.8%) and 30 patients (54.5%), respectively, were in clinical remission. Post hoc Bayesian analysis showed that the probabilities that triple combination therapy produced a higher endoscopic remission rate (33.5%; 95% credible interval, 22.4-45.7) than placebo (14%), vedolizumab monotherapy (27%), or adalimumab monotherapy (30%) were 99.9% or higher, 86.3%, and 71.4%, respectively. Six patients had serious adverse events. CONCLUSIONS: Combination therapy resulted in endoscopic and clinical remission at week 26 in 34.5% and 54.5% of patients, respectively, with no safety signal related to the treatment regimen. This supports further evaluation of combination therapy in CD. CLINICALTRIALS: gov number: NCT02764762.

4.
Gastroenterology ; 161(3): 837-852.e9, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34052278

RESUMO

BACKGROUND & AIMS: This study compared the effectiveness of the Specific Carbohydrate Diet (SCD) to the Mediterranean diet (MD) as treatment for Crohn's disease (CD) with mild to moderate symptoms. METHODS: Adult patients with CD and with mild-to-moderate symptoms were randomly assigned 1:1 to consume the MD or SCD for 12 weeks. For the first 6 weeks, participants received prepared meals and snacks according to their assigned diet. After 6 weeks, participants were instructed to follow the diet independently. The primary outcome was symptomatic remission at week 6. Key secondary outcomes at week 6 included fecal calprotectin (FC) response (FC <250 µg/g and reduction by >50% among those with baseline FC >250 µg/g) and C-reactive protein (CRP) response (high-sensitivity CRP <5 mg/L and >50% reduction from baseline among those with high-sensitivity CRP >5 mg/L). RESULTS: The study randomized 194 patients, and 191 were included in the efficacy analyses. The percentage of participants who achieved symptomatic remission at week 6 was not superior with the SCD (SCD, 46.5%; MD, 43.5%; P = .77). FC response was achieved in 8 of 23 participants (34.8%) with the SCD and in 4 of 13 participants (30.8%) with the MD (P = .83). CRP response was achieved in 2 of 37 participants (5.4%) with the SCD and in 1 of 28 participants (3.6%) with the MD (P = .68). CONCLUSIONS: The SCD was not superior to the MD to achieve symptomatic remission, FC response, and CRP response. CRP response was uncommon. Given these results, the greater ease of following the MD and other health benefits associated with the MD, the MD may be preferred to the SCD for most patients with CD with mild to moderate symptoms. ClinicalTrials.gov Identifier: NCT03058679.


Assuntos
Doença de Crohn/dietoterapia , Dieta Mediterrânea , Carboidratos da Dieta/administração & dosagem , Adulto , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Pesquisa Comparativa da Efetividade , Doença de Crohn/sangue , Doença de Crohn/diagnóstico , Doença de Crohn/microbiologia , Dieta Mediterrânea/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Fezes/química , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal , Humanos , Mediadores da Inflamação/sangue , Complexo Antígeno L1 Leucocitário/metabolismo , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
5.
Clin Gastroenterol Hepatol ; 17(9): 1807-1813.e1, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30267862

RESUMO

BACKGROUND & AIMS: Individuals with inflammatory bowel diseases (IBDs) have an increased risk of developing colorectal cancer (CRC). Although family history of CRC is a well-established risk factor in healthy individuals, its role in patients with IBD is less clear. We aimed to estimate the risk of CRC in a cohort of patients with IBD from Utah and the significance of family history of CRC in a first-degree relative (FDR). METHODS: We identified Utah residents with IBD, using the Intermountain Healthcare and University of Utah Health Sciences databases, from January 1, 1996, through December 31, 2011. CRCs were identified using the Utah Cancer Registry and linked to pedigrees from the Utah Population Database. CRC incidence was compared with that of the state population by standardized incidence ratios (SIRs). RESULTS: A cohort of 9505 individuals with IBD was identified and 101 developed CRC during the study period. The SIR for CRC in patients with Crohn's disease was 3.4 (95% CI, 2.3-4.4), and in patients with ulcerative colitis was 5.2 (95% CI, 3.9-6.6). Patients with IBD and a concurrent diagnosis of primary sclerosing cholangitis had the greatest risk of CRC (SIR, 14.8; 95% CI, 8.3-21.2). A history of CRC in a FDR was associated with a nearly 8-fold increase in risk of CRC in patients with IBD (SIR, 7.9; 95% CI, 1.6-14.3), compared with the state population. CONCLUSIONS: Patients with IBD have a 3- to 5-fold increase in risk of CRC, and those with CRC in a FDR have an almost 8-fold increase in risk. Family history may act as a simple measure to identify individuals with IBD at highest risk for CRC and indicates the need for enhanced surveillance in this population.


Assuntos
Colangite Esclerosante/epidemiologia , Colite Ulcerativa/epidemiologia , Neoplasias Colorretais/epidemiologia , Doença de Crohn/epidemiologia , Anamnese , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Risco , Utah/epidemiologia , Adulto Jovem
6.
Gastroenterology ; 155(4): 1098-1108.e9, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29964043

RESUMO

BACKGROUND & AIMS: Parenteral methotrexate induces clinical remission but not endoscopic improvement of mucosal inflammation in patients with ulcerative colitis (UC). We performed a randomized, placebo-controlled trial to assess the efficacy of parenteral methotrexate in maintaining steroid-free response or remission in patients with UC after induction therapy with methotrexate and steroids. METHODS: We performed a 48-week trial, from February 2012 through May 2016, of 179 patients with active UC (Mayo score of 6-12 with endoscopy subscore ≥ 2) despite previous conventional or biological therapy. The study comprised a 16-week open label methotrexate induction period followed by a 32-week double-blind, placebo-controlled maintenance period. Patients were given subcutaneous methotrexate (25 mg/wk) and a 12-week steroid taper. At week 16, steroid-free responders were randomly assigned to groups that either continued methotrexate (25 mg/wk, n = 44) or were given placebo (n = 40) until week 48. We compared the efficacy of treatment by analyzing the proportion of patients who remained relapse free and were in remission at week 48 without use of steroids or other medications to control disease activity. RESULTS: Ninety-one patients (51%) achieved response at week 16, and 84 patients were included in the maintenance period study. During this period, 60% of patients in the placebo group (24/40) and 66% in the methotrexate group (29/44) had a relapse of UC (P = .75). At week 48, 30% of patients in the placebo group (12/40) and 27% of patients in the methotrexate group (12/44) were in steroid-free clinical remission without need for additional therapies (P = .86). No new safety signals for methotrexate were detected. CONCLUSIONS: Parenteral methotrexate (25 mg/wk) was not superior to placebo in preventing relapses of UC in patients who achieved steroid-free response during induction therapy. ClinicalTrials.gov, Number: NCT01393405.


Assuntos
Anti-Inflamatórios/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/administração & dosagem , Metotrexato/administração & dosagem , Esteroides/administração & dosagem , Adulto , Idoso , Anti-Inflamatórios/efeitos adversos , Colite Ulcerativa/diagnóstico , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Feminino , Fármacos Gastrointestinais/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Masculino , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Indução de Remissão , Esteroides/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
9.
Dig Dis Sci ; 62(8): 2126-2132, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28050782

RESUMO

BACKGROUND AND AIMS: The molecular, endoscopic, and histological features of IBD-associated CRC differ from sporadic CRC. The objective of this study was to describe the prevalence, clinical features, and prognosis of IBD-associated CRC compared to patients with sporadic CRC in a US statewide population-based cohort. METHODS: All newly diagnosed cases of CRC between 1996 and 2011 were obtained from Utah Cancer Registry. IBD was identified using a previously validated algorithm, from statewide databases of Intermountain Healthcare, University of Utah Health Sciences, and the Utah Population Database. Logistic regression was performed to identify risk factors associated with IBD-associated cancer and Cox regression for differences in survival. RESULTS: Among 12,578 patients diagnosed with CRC, 101 (0.8%) had a prior history of IBD (61 ulcerative colitis and 40 Crohn's disease). The mean age at CRC diagnosis was greater for patients without IBD than those with IBD (67.1 vs 52.8 years, P < 0.001). Individuals with IBD-associated CRC were more likely to be men (odds ratio [OR] 1.90, 95% CI 1.23-2.92), aged less than 65 years (OR 6.77, 95% CI 4.06-11.27), and have CRC located in the proximal colon (OR 2.79, 95% CI 1.85-4.20) than those with sporadic CRC. Nearly 20% of the IBD-associated CRCs had evidence of primary sclerosing cholangitis. After adjustment for age, gender, and stage at diagnosis, the excess hazard of death after CRC diagnosis was 1.7 times higher in IBD than in non-IBD patients (95% CI 1.27-2.33). CONCLUSIONS: The features of patients with CRC and IBD differ significantly from those without IBD and may be associated with increased mortality.


Assuntos
Colite Ulcerativa/complicações , Neoplasias Colorretais/etiologia , Doença de Crohn/complicações , Adulto , Fatores Etários , Idade de Início , Idoso , Colangite Esclerosante/complicações , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/patologia , Colo/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Doença de Crohn/epidemiologia , Doença de Crohn/patologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores Sexuais , Utah/epidemiologia
10.
Gastroenterology ; 149(6): 1575-1586, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26278503

RESUMO

BACKGROUND & AIMS: Inflammatory bowel disease (IBD) has familial aggregation in African Americans (AAs), but little is known about the molecular genetic susceptibility. Mapping studies using the Immunochip genotyping array expand the number of susceptibility loci for IBD in Caucasians to 163, but the contribution of the 163 loci and European admixture to IBD risk in AAs is unclear. We performed a genetic mapping study using the Immunochip to determine whether IBD susceptibility loci in Caucasians also affect risk in AAs and identify new associated loci. METHODS: We recruited AAs with IBD and without IBD (controls) from 34 IBD centers in the United States; additional controls were collected from 4 other Immunochip studies. Association and admixture loci were mapped for 1088 patients with Crohn's disease, 361 with ulcerative colitis, 62 with IBD type unknown, and 1797 controls; 130,241 autosomal single-nucleotide polymorphisms (SNPs) were analyzed. RESULTS: The strongest associations were observed between ulcerative colitis and HLA rs9271366 (P = 7.5 × 10(-6)), Crohn's disease and 5p13.1 rs4286721 (P = 3.5 × 10(-6)), and IBD and KAT2A rs730086 (P = 2.3 × 10(-6)). Additional suggestive associations (P < 4.2 × 10(-5)) were observed between Crohn's disease and IBD and African-specific SNPs in STAT5A and STAT3; between IBD and SNPs in IL23R, IL12B, and C2orf43; and between ulcerative colitis and SNPs near HDAC11 and near LINC00994. The latter 3 loci have not been previously associated with IBD, but require replication. Established Caucasian associations were replicated in AAs (P < 3.1 × 10(-4)) at NOD2, IL23R, 5p15.3, and IKZF3. Significant admixture (P < 3.9 × 10(-4)) was observed for 17q12-17q21.31 (IZKF3 through STAT3), 10q11.23-10q21.2, 15q22.2-15q23, and 16p12.2-16p12.1. Network analyses showed significant enrichment (false discovery rate <1 × 10(-5)) in genes that encode members of the JAK-STAT, cytokine, and chemokine signaling pathways, as well those involved in pathogenesis of measles. CONCLUSIONS: In a genetic analysis of 3308 AA IBD cases and controls, we found that many variants associated with IBD in Caucasians also showed association evidence with these diseases in AAs; we also found evidence for variants and loci not previously associated with IBD. The complex genetic factors that determine risk for or protection against IBD in different populations require further study.


Assuntos
Negro ou Afro-Americano/genética , Doenças Inflamatórias Intestinais/genética , Polimorfismo de Nucleotídeo Único , População Branca/genética , Adulto , Idoso , Colite Ulcerativa/genética , Doença de Crohn/genética , Feminino , Loci Gênicos , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos/etnologia , Adulto Jovem
11.
J Immunol ; 193(3): 1024-34, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24973447

RESUMO

Increasing evidence suggests that type 1 IFN (IFN-αß) is associated with pathogenesis of Th1-mediated type 1 diabetes (T1D). A major source of IFN-αß is plasmacytoid dendritic cells (pDCs). In this study, we analyzed peripheral blood pDC numbers and functions in at-risk, new-onset, and established T1D patients and controls. We found that subjects at risk for T1D and new-onset and established T1D subjects possessed significantly increased pDCs but similar number of myeloid DCs when compared with controls. pDC numbers were not affected by age in T1D subjects but declined with increasing age in control subjects. It was demonstrated that IFN-α production by PBMCs stimulated with influenza viruses was significantly higher in T1D subjects than in controls, and IFN-α production was correlated with pDC numbers in PBMCs. Of interest, only T1D-associated Coxsackievirus serotype B4 but not B3 induced majority of T1D PBMCs to produce IFN-α, which was confirmed to be secreted by pDCs. Finally, in vitro studies demonstrated IFN-α produced by pDCs augmented Th1 responses, with significantly greater IFN-γ-producing CD4(+) T cells from T1D subjects. These findings indicate that increased pDCs and their IFN-αß production may be associated with this Th1-mediated autoimmune disease, especially under certain viral infections linked to T1D pathogenesis.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/patologia , Diabetes Mellitus Tipo 1/imunologia , Interferon-alfa/biossíntese , Células Th1/imunologia , Regulação para Cima/imunologia , Adolescente , Adulto , Contagem de Células Sanguíneas , Diferenciação Celular/imunologia , Células Cultivadas , Criança , Pré-Escolar , Células Dendríticas/virologia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/virologia , Feminino , Humanos , Lactente , Interferon-alfa/fisiologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/virologia , Masculino , Orthomyxoviridae/imunologia , Células Th1/patologia , Células Th1/virologia , Adulto Jovem
12.
J Theor Biol ; 363: 404-11, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25117472

RESUMO

It is well established that in most belligerent countries in World Wars 1 and 2, sex ratios (proportions male at birth) rose during and just after hostilities: then, a year or so later, they declined to normal levels. There is no established explanation for these phenomena. I have previously written on this problem. Here, I elaborate on my previous papers in three ways. First, further evidence (some analytic and some synthetic) is adduced to support the hypothesis that the rises were caused by high parental coital rates. Second, further evidence is adduced to suggest that these high coital rates occurred disproportionately often in couples of whom the man was (or had been) in the armed services. Thirdly, evidence is offered to suggest why such rises in sex ratio were not reported in other conflicts.


Assuntos
Modelos Biológicos , Razão de Masculinidade , Comportamento Sexual/história , Feminino , História do Século XX , Humanos , Masculino , Projetos de Pesquisa , Inquéritos e Questionários , I Guerra Mundial , II Guerra Mundial
13.
J Crohns Colitis ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38224550

RESUMO

BACKGROUND: Mesenchymal stromal cells are suggested to play a critical role in the Crohn's Disease (CD) associated fibrosis. MAPKAPK2 (MK2) has emerged as a potential therapeutic target to reduce inflammation in CD. However, cell-specific pattern of pMK2 activation and its role in the CD associated fibrosis are unknown. The objectives of this study were to evaluate cell-specific changes in MK2 activity between predominantly inflammatory CD versus CD with fibrotic complication and define the role of stromal cell-specific MK2 activation in CD-associated fibrosis. METHODS: CD tissue, CD tissue derived mesenchymal stromal cells known as myo-/fibroblasts (CD-MFs), fibroblast specific MK2 conditional KO mice were used. RESULTS: We observed that in the inflamed area of predominantly inflammatory CD, high MK2 activity was equally distributed between mesenchymal and hematopoietic cells. By contrast, in CD with fibrotic complications, high MK2 activity was mostly associated with mesenchymal stromal cells. Using ex vivo CD tissue explants and IL-10KO murine colitis model, we demonstrated that pro-fibrotic responses are significantly reduced by treatment with the MK2 inhibitor PF-3644022. Inhibition of MK2 activity in primary cultures of CD-MFs significantly reduced basal and TGF-ß1-induced profibrotic responses. Using fibroblast-specific MK2 knockout mice in chronic DSS colitis, we demonstrated that fibroblast intrinsic MK2 signaling is among the key processes involved in the chronic inflammation induced profibrotic responses. CONCLUSIONS: Our data suggest that activation of MK2 within fibroblasts contributes to the chronic inflammation induced fibrosis in CD and that targeting MK2 has potential for the development of novel therapeutic approaches for fibrosis in CD.

14.
Toxicol Res (Camb) ; 13(1): tfad120, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38223529

RESUMO

Fialuridine (FIAU) is a nucleoside-based drug that caused liver failure and deaths in a human clinical trial that were not predicted by nonclinical safety studies. A recent report concluded that a TK-NOG humanized liver (hu-liver) mouse model detected human-specific FIAU liver toxicity, and broader use of that model could improve drug safety testing. We further evaluated this model at similar dose levels to assess FIAU sensitivity and potential mechanistic biomarkers. Although we were unable to reproduce the marked acute liver toxicity with two separate studies (including one with a "sensitized" donor), we identified molecular biomarkers reflecting the early stages of FIAU mitochondrial toxicity, which were not seen with its stereoisomer (FIRU). Dose dependent FIAU-induced changes in hu-liver mice included more pronounced reductions in mitochondrial to nuclear DNA (mtDNA/nucDNA) ratios in human hepatocytes compared to mouse hepatocytes and kidneys of the same animals. FIAU treatment also triggered a p53 transcriptional response and opposing changes in transcripts of nuclear- and mitochondrial-encoded mitochondrial proteins. The time dependent accumulation of FIAU into mtDNA is consistent with the ≥9-week latency of liver toxicity observed for FIAU in the clinic. Similar changes were observed in an in vitro micro-patterned hepatocyte coculture system. In addition, FIAU-dependent mtDNA/nucDNA ratio and transcriptional alterations, especially reductions in mitochondrially encoded transcripts, were seen in livers of non-engrafted TK-NOG and CD-1 mice dosed for a shorter period. Conclusion: These mechanistic biomarker findings can be leveraged in an in vitro model and in a more routine preclinical model (CD-1 mice) to identify nucleosides with such a FIAU-like mitochondrial toxicity mechanistic liability potential. Further optimization of the TK-NOG hu-liver mouse model is necessary before broader adoption for drug safety testing.

15.
medRxiv ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38370739

RESUMO

Background and aims: Inflammatory Bowel Diseases (IBD) are chronic inflammatory conditions influenced heavily by environmental factors. DNA methylation is a form of epigenetic regulation linking environmental stimuli to gene expression changes and inflammation. Here, we investigated how DNA methylation of the TNF promoter differs between inflamed and uninflamed mucosa of IBD patients, including anti-TNF responders and non-responders. Methods: We obtained mucosal biopsies from 200 participants (133 IBD and 67 controls) and analyzed TNF promoter methylation using bisulfite sequencing, comparing inflamed with uninflamed segments, in addition to paired inflamed/uninflamed samples from individual patients. We conducted similar analyses on purified intestinal epithelial cells from bowel resections. We also compared TNF methylation levels of inflamed and uninflamed mucosa from a separate cohort of 15 anti-TNF responders and 17 non-responders. Finally, we sequenced DNA methyltransferase genes to identify rare variants in IBD patients and functionally tested them using rescue experiments in a zebrafish genetic model of DNA methylation deficiency. Results: TNF promoter methylation levels were decreased in inflamed mucosa of IBD patients and correlated with disease severity. Isolated IECs from inflamed tissue showed proportional decreases in TNF methylation. Anti-TNF non-responders showed lower levels of TNF methylation than responders in uninflamed mucosa. Our sequencing analysis revealed two missense variants in DNMT1, one of which had reduced function in vivo. Conclusions: Our study reveals an association of TNF promoter hypomethylation with mucosal inflammation, suggesting that IBD patients may be particularly sensitive to inflammatory environmental insults affecting DNA methylation. Together, our analyses indicate that TNF promoter methylation analysis may aid in the characterization of IBD status and evaluation of anti-TNF therapy response.

17.
Clin Gastroenterol Hepatol ; 11(3): 286-92; quiz e24, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23200982

RESUMO

BACKGROUND & AIMS: Some women with inflammatory bowel disease require therapy with tumor necrosis factor (TNF) antagonists during pregnancy. It is not clear whether these drugs are transferred to the fetus via the placenta and then cleared, or whether structurally different TNF antagonists have different rates of transfer. METHODS: We studied 31 pregnant women with inflammatory bowel disease receiving infliximab (IFX, n = 11), adalimumab (ADA, n = 10), or certolizumab (CZP, n = 10). Serum concentrations of the drugs were measured at birth in the mother, infant, and in cord blood, and then monthly in the infant until the drugs were undetectable. Drug concentrations in the cord and the infant at birth were compared with those of the mother. RESULTS: Concentrations of IFX and ADA, but not CZP, were higher in infants at birth and their cords than in their mothers. The levels of CZP in infants and their cords were less than 2 µg/mL. The median level of IFX in the cord was 160% that of the mother, the median level of ADA in the cord was 153% that of the mother, and the median level of CZP in the cord was 3.9% that of the mother. IFX and ADA could be detected in the infants for as long as 6 months. No congenital anomalies or serious complications were reported. CONCLUSIONS: The TNF antagonists IFX and ADA are transferred across the placenta and can be detected in infants at birth; the drugs were detected in infants up to 6 months after birth. CZP has the lowest level of placental transfer, based on levels measured in cords and infants at birth, of the drugs tested.


Assuntos
Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais/farmacocinética , Fatores Imunológicos/farmacocinética , Doenças Inflamatórias Intestinais/tratamento farmacológico , Polietilenoglicóis/farmacocinética , Complicações na Gravidez/tratamento farmacológico , Soro/química , Adalimumab , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Certolizumab Pegol , Feminino , Sangue Fetal/química , Seguimentos , Humanos , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Lactente , Recém-Nascido , Infliximab , Polietilenoglicóis/administração & dosagem , Gravidez , Fator de Necrose Tumoral alfa/antagonistas & inibidores
18.
Am J Gastroenterol ; 108(12): 1891-900, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24126633

RESUMO

OBJECTIVES: In Crohn's disease (CD), clinical symptoms correspond poorly to inflammatory disease activity. Biomarkers reflective of mucosal and bowel wall inflammation would be useful to monitor disease activity. The EMBARK study evaluated disease activity in patients with ulcerative colitis (UC) and CD, and used endoscopy with or without cross-sectional imaging for biomarker discovery. METHODS: UC (n=107) and CD (n=157) patients were characterized and underwent ileocolonoscopy (ICO). A subset of CD patients (n=66) also underwent computed tomography enterography (CTE). ICO and CTE were scored by a gastroenterologist and radiologist who incorporated findings of inflammation into a single score (ICO-CTE) for patients that underwent both procedures. Serum and fecal biomarkers were evaluated for association with the Mayo Clinic endoscopy score in UC patients and with ICO alone or ICO-CTE in CD patients. Individual biomarkers with a moderate degree of correlation (P≤0.3) were evaluated using multivariate analysis with model selection using a stepwise procedure. RESULTS: In UC, ordinal logistic regression using Mayo Clinic endoscopy subscore selected the combination of fecal calprotectin and serum matrix metalloproteinase 9 (MMP9; pseudo R(2)=0.353). In CD, we found that use of the ICO-CTE increased specificity of known biomarkers. Using ICO-CTE as the dependent variable for biomarker discovery, the selected biomarkers were the combination of fecal calprotectin, serum MMP9, and serum IL-22 (r=0.699). CONCLUSIONS: Incorporation of both ICO and CTE into a single measure increased biomarker performance in CD. Combinations of fecal calprotectin and serum MMP9 for UC, and combinations of fecal calprotectin, serum MMP9, and serum interleukin-22 in CD, demonstrated the strongest association with imaging/endoscopy-defined inflammation.


Assuntos
Biomarcadores/metabolismo , Doença de Crohn/metabolismo , Fezes/química , Interleucinas/sangue , Complexo Antígeno L1 Leucocitário/metabolismo , Metaloproteinase 9 da Matriz/sangue , Adolescente , Adulto , Idoso , Colonoscopia , Doença de Crohn/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Interleucina 22
19.
Endosc Int Open ; 11(7): E653-E659, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37614326

RESUMO

Background and study aims In gastrointestinal endoscopy, biopsies must transit through the accessory channel and cap, presenting an opportunity for loss of tissue. We sought to determine the incidence of specimen retention in the accessory channel or cap and identify procedure characteristics associated with specimen retention. Patients and methods After completion of standard endoscopic procedures in which biopsies were obtained, the biopsy cap and accessory channel were inspected, brushed, and irrigated for any retained biopsy specimens according to a standard protocol. For controls, the same protocol was applied to procedures in which biopsies were not obtained. Specimen bottles from the recovery protocol were sent for pathological examination regardless of whether any visible tissue was present. Results A total of 216 outpatient procedures were included: 55 esophagogastroduodenoscopies (EGDs) and 50 colonoscopies in which biopsies were obtained and 56 EGDs and 55 colonoscopies in the control group. Retained specimens were found in either the cap or channel in 50 of 105 (48%). In 20 of 105 (19%), retained specimens were found just in the cap, in six of 105 (5.7%), retained specimens were found just in the channel, while in 24 of 105 (23%), retained specimens were found in both the cap and channel. Retained specimens were more likely to be found in EGDs compared to colonoscopies (58% vs. 36%, P = 0.031). No retained specimens were found in the control group. Conclusions Retained specimens are startingly common in standard gastrointestinal endoscopic procedures and could potentially change diagnoses and management. Quality improvement measures should be instituted to monitor prevalence of retained biopsies and methods to prevent them should be developed.

20.
Lancet Gastroenterol Hepatol ; 8(1): 43-55, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36240801

RESUMO

BACKGROUND: Etrolizumab is a gut-targeted anti-ß7 monoclonal antibody targeting α4ß7 and αEß7 integrins. We aimed to compare the safety and efficacy of two doses of etrolizumab with placebo in patients with Crohn's disease. METHODS: BERGAMOT was a randomised, placebo-controlled, double-blind, phase 3 study done at 326 treatment centres worldwide. We included patients aged 18-80 years with moderately to severely active Crohn's disease (Crohn's Disease Activity Index [CDAI] score of 220-480, and a mean daily stool frequency score of ≥6 or a mean daily stool frequency score of >3, and a mean daily abdominal pain score of >1, as well as the presence of active inflammation on screening ileocolonoscopy) who had intolerance, inadequate response, or no response to one or more of corticosteroids, immunosuppressants, or anti-TNF therapy within the past 5 years. BERGAMOT consisted of three induction cohorts (a placebo-controlled, double-blind exploratory cohort [cohort 1]; an active treatment cohort not containing a placebo control [cohort 2]; and a placebo-controlled, double-blind pivotal cohort [cohort 3]) and one maintenance cohort. In induction cohort 3, during the 14-week induction, patients were randomly assigned (2:3:3) to receive matched placebo, 105 mg etrolizumab subcutaneously every 4 weeks (at weeks 0, 4, 8, and 12) or 210 mg etrolizumab subcutaneously (at weeks 0, 2, 4, 8, and 12), stratified by concomitant treatment with oral corticosteroids, concomitant treatment with immunosuppressants, baseline disease activity, and previous exposure to anti-TNF therapy. To preserve masking, all patients received two injections at weeks 0, 4, 8, and 12 and one injection at week 2. Week 14 etrolizumab responders from all cohorts were re-randomly assigned (1:1) to receive 105 mg etrolizumab (etrolizumab maintenance group) or placebo (placebo maintenance group) every 4 weeks for 52 weeks; patients in the induction placebo group underwent a sham re-randomisation to preserve masking. During maintenance, randomisation was stratified by CDAI remission status, concomitant treatment with oral corticosteroids, induction dose regimen, and previous exposure to anti-TNF therapy. All participants and study site personnel were masked to treatment assignment for both induction and maintenance. Co-primary induction endpoints at week 14 (placebo vs 210 mg etrolizumab) were clinical remission (mean stool frequency ≤3 and mean abdominal pain ≤1, with no worsening) and endoscopic improvement (≥50% reduction in Simple Endoscopic Score for Crohn's Disease [SES-CD]). Co-primary maintenance endpoints at week 66 (placebo vs etrolizumab) were clinical remission and endoscopic improvement. Efficacy was analysed using a modified intention-to-treat (mITT) population, defined as all randomised patients who received at least one dose of study drug (induction) and as all patients re-randomised into maintenance who received at least one dose of study drug in the maintenance phase (maintenance). Safety analyses included all patients who received at least one dose of study drug. Maintenance safety analyses include all adverse events occurring in both induction and maintenance. This trial is registered with ClinicalTrials.gov, NCT02394028, and is closed to recruitment. FINDINGS: Between March 20, 2015, and Sept 7, 2021, 385 patients (209 [54%] male and 326 [85%] white) were randomly assigned in induction cohort 3 to receive placebo (n=97), 105 mg etrolizumab (n=143), or 210 mg etrolizumab (n=145). 487 patients had a CDAI-70 response in any of the induction cohorts and were enrolled into the maintenance cohort, of whom 434 had a response to etrolizumab and were randomly assigned to placebo (n=217) or 105 mg etrolizumab (n=217). At week 14, 48 (33%) of 145 patients in the 210 mg induction etrolizumab group versus 28 (29%) of 96 patients in the placebo induction group were in clinical remission (adjusted treatment difference 3·8% [95% CI -8·3 to 15·3]; p=0·52), and 40 (27%) versus 21 (22%) showed endoscopic improvement (5·8% [-5·4 to 17·1]; p=0·32). At week 66, a significantly higher proportion of patients receiving etrolizumab than those receiving placebo had clinical remission (76 [35%] of 217 vs 52 [24%] of 217; adjusted treatment difference 11·3% [95% CI 2·7-19·7]; p=0·0088) and endoscopic improvement (51 [24%] vs 26 [12%]; 11·5% [4·1-18·8]; p=0·0026). Similar proportions of patients reported one or more adverse events during induction (95 [66%] of 143 in the 105 mg etrolizumab group, 85 [59%] of 145 in the 210 mg etrolizumab group, and 51 [53%] of 96 in the placebo group) and maintenance (189 [87%] of 217 in the etrolizumab group and 190 [88%] of 217 in the placebo group). During induction, the most common treatment-related adverse events were injection site erythema (six [4%] of 143 in the 105 mg etrolizumab group, four [3%] of 145 in the 210 mg etrolizumab group, and none of 96 in the placebo group), and arthralgia (two [1%], one [1%], and four [4%]). In the maintenance cohort, the most common treatment-related adverse events were injection site erythema (six [3%] of 217 in the etrolizumab group vs 14 [6%] of 217 in the placebo: group), arthralgia (five [2%] vs eight [4%]), and headache (five [2%] vs seven [3%]). The most common serious adverse event was exacerbation of Crohn's disease (14 [6%] of 217 patients taking placebo and four [2%] of 217 patients taking 105 mg etrolizumab in the maintenance cohort). INTERPRETATION: A significantly higher proportion of patients with moderately to severely active Crohn's disease achieved clinical remission and endoscopic improvement with etrolizumab than placebo during maintenance, but not during induction. FUNDING: F Hoffmann-La Roche.


Assuntos
Doença de Crohn , Humanos , Masculino , Feminino , Doença de Crohn/tratamento farmacológico , Doença de Crohn/induzido quimicamente , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Quimioterapia de Indução , Imunossupressores/efeitos adversos , Dor Abdominal/induzido quimicamente
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