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Journal articleSinganayagam A, Glanville N, Cuthbertson L, et al., 2019, , Science Translational Medicine, Vol: 11, Pages: 1-13, ISSN: 1946-6234
Bacterial infection commonly complicates inflammatory airway diseases such as chronic obstructive pulmonary disease (COPD). The mechanisms of increased infection susceptibility and how use of the commonly prescribed therapy inhaled corticosteroids (ICS) accentuates pneumonia risk in COPD are poorly understood. Here, using analysis of samples from patients with COPD, we show that ICS use is associated with lung microbiota disruption leading to proliferation of streptococcal genera, an effect that could be recapitulated in ICS-treated mice. To study mechanisms underlying this effect, we used cellular and mouse models of streptococcal expansion with Streptococcus pneumoniae, an important pathogen in COPD, to demonstrate that ICS impairs pulmonary clearance of bacteria through suppression of the antimicrobial peptide cathelicidin. ICS impairment of pulmonary immunity was dependent on suppression of cathelicidin because ICS had no effect on bacterial loads in mice lacking cathelicidin (Camp-/-) and exogenous cathelicidin prevented ICS-mediated expansion of streptococci within the microbiota and improved bacterial clearance. Suppression of pulmonary immunity by ICS was mediated by augmentation of the protease cathepsin D. Collectively, these data suggest a central role for cathepsin D/cathelicidin in the suppression of antibacterial host defense by ICS in COPD. Therapeutic restoration of cathelicidin to boost antibacterial immunity and beneficially modulate the lung microbiota might be an effective strategy in COPD.
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Journal articleBates KA, Shelton JMG, Mercier VL, et al., 2019, , Frontiers in Microbiology, Vol: 10, ISSN: 1664-302X
The emerging fungal pathogen, Batrachochytrium salamandrivorans (Bsal) is responsible for the catastrophic decline of European salamanders and poses a threat to amphibians globally. The amphibian skin microbiome can influence disease outcome for several host-pathogen systems, yet little is known of its role in Bsal infection. In addition, many experimental in-vivo amphibian disease studies to date have relied on specimens that have been kept in captivity for long periods without considering the influence of environment on the microbiome and how this may impact the host response to pathogen exposure. We characterized the impact of captivity and exposure to Bsal on the skin bacterial and fungal communities of two co-occurring European newt species, the smooth newt, Lissotriton vulgaris and the great-crested newt, Triturus cristatus. We show that captivity led to significant losses in bacterial and fungal diversity of amphibian skin, which may be indicative of a decline in microbe-mediated protection. We further demonstrate that in both L. vulgaris and T. cristatus, Bsal infection was associated with changes in the composition of skin bacterial communities with possible negative consequences to host health. Our findings advance current understanding of the role of host-associated microbiota in Bsal infection and highlight important considerations for ex-situ amphibian conservation programmes.
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Journal articleAllegretti JR, Mullish BH, Kelly C, et al., 2019, , Lancet, Vol: 394, Pages: 420-431
Developments in high-throughput microbial genomic sequencing and other systems biology techniques have given novel insight into the potential contribution of the gut microbiota to health and disease. As a result, an increasing number of diseases have been characterised by distinctive changes in the composition and functionality of the gut microbiota; however, whether such changes are cause, consequence, or incidental to the disease in question remains largely uncertain. Restoration of the gut microbiota to a premorbid state is a key novel therapeutic approach of interest, and faecal microbiota transplantation-the transfer of prescreened stool from healthy donors into the gastrointestinal tract of patients-is gaining increasing importance in both the clinical and research settings. At present, faecal microbiota transplantation is only recommended in the treatment of recurrent Clostridioides difficile infection, although a large number of trials are ongoing worldwide exploring other potential therapeutic indications.
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Conference paperRiaz Z, Wright M, Atkinson S, et al., 2019,
Malignant and cirrhotic ascites demonstrate a similar microbiome profile
, British Association for the Study of the Liver (BASL) Annual Meeting -
Journal articleAllegretti JA, Kassam Z, Carrellas M, et al., 2019, , American Journal of Gastroenterology, Vol: 114, Pages: 1071-1079, ISSN: 1572-0241
Background: Primary sclerosing cholangitis (PSC) is a cholestatic liver disease with no effective medical therapies. A perturbation of the gut microbiota has been described in association with PSC, and fecal microbiota transplantation (FMT) has been reported to restore the microbiome in other disease states. Accordingly, we aimed to evaluate the safety, change in liver enzymes, microbiota and metabolomic profiles in PSC patients after FMT.Methods: Open-label pilot study of PSC patients with concurrent inflammatory bowel disease (IBD) and ALP > 1.5X the upper limit of normal. Participants underwent a single FMT by colonoscopy. Liver enzyme profiles and stool microbiome and metabolomic analysis was conducted at baseline and week 1, 4, 8, 12 and 24 post-FMT. The primaryoutcome was safety and secondary outcomes include a decrease in ALP ≥50% from baseline by week 24 post-FMT, as well as stool microbiota (by 16S rRNA gene profiling) and metabonomic dynamics were assessed.Results. Ten patients underwent FMT. Nine patients had ulcerative colitis and 1 with Crohn’s colitis. The mean baseline ALP was 489 U/L. There were no related adverse events. Overall, 30% (3/10) experienced a ≥50% decrease ALP. The diversity increased in all patients post-FMT, as early as week 1 (p<0.01). Importantly, abundance of engrafter operational taxanomic units (OTUs) in patients post-FMT correlated with decreased ALP (p=0.02).Conclusion: To our knowledge, this first study to demonstrate that FMT in PSC is safe. Additionally, increases in bacterial diversity and engraftment may correlate with an improvement in ALP among PSC patients.
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Journal articleNathwani R, Mullish BH, Kockerling D, et al., 2019, , Gut, Vol: 69, Pages: 726-780, ISSN: 0017-5749
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Conference paperGhani R, Gan C, Mullish BH, et al., 2019, , British Association of Urological Surgeons Annual Scientific Meeting, Publisher: SAGE Publications, Pages: 83-85, ISSN: 2051-4158
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Journal articleMcDonald JA, Perez JL, Mullish BH, et al., 2019, , Gastroenterology, Vol: 156, Pages: S-898, ISSN: 0016-5085
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Journal articleChurchward MA, Michaud ER, Blanco JM, et al., 2019, , Gastroenterology, Vol: 156, Pages: S-455, ISSN: 0016-5085
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Journal articleAllegretti JR, Hurtado J, Carrellas M, et al., 2019, , Gastroenterology, Vol: 156, ISSN: 0016-5085
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