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Biology subjects

Braybrooke, R.

Publications and source records attributed to Braybrooke, R..

4 recordsLinked to original sources

A lung targeted miR-29 Mimic as a Therapy for Pulmonary Fibrosis

microRNAs are non-coding RNAs that negatively regulate gene networks. Previously, we reported a systemically delivered miR-29 mimic MRG-201 that reduced fibrosis in animal models, but at doses prohibiting clinical translation. Here, we generated MRG-229, a next-gen miR-29 mimic with improved chemical stability, conjugated with the internalization moiety BiPPB (PDGFbetaR-specific bicyclic peptide). In TGF-b-treated human lung fibroblasts and precision cut lung slices, MRG-229 decreased COL1A1 and ACTA2 gene expression and reduced collagen production. In bleomycin-treated mice, intravenous or subcutaneous delivery of MRG-229 downregulated profibrotic gene programs at doses more than ten-fold lower than the original compound. In rats and non-human primates, and at clinically relevant doses, MRG-229 was well tolerated, with no adverse findings observed. In human peripheral blood decreased mir-29 concentrations were associated with increased mortality in two cohorts potentially identified as a target population for treatment. Collectively, our results provide support for the development of MRG-229 as a potential therapy in humans with IPF. One Sentence SummaryOne Sentence Summary: A stabilized, next-generation miR-29 mimic has been developed that demonstrates efficacy at commercially viable doses with a robust safety margin in non-human primates.

molecular biology↗

Genome-wide association study of susceptibility to idiopathic pulmonary fibrosis

RationaleIdiopathic pulmonary fibrosis (IPF) is a complex lung disease characterised by scarring of the lung that is believed to result from an atypical response to injury of the epithelium. The mechanisms by which this arises are poorly understood and it is likely that multiple pathways are involved. The strongest genetic association with IPF is a variant in the promoter of MUC5B where each copy of the risk allele confers a five-fold risk of disease. However, genome-wide association studies have reported additional signals of association implicating multiple pathways including host defence, telomere maintenance, signalling and cell-cell adhesion.\n\nObjectivesTo improve our understanding of mechanisms that increase IPF susceptibility by identifying previously unreported genetic associations.\n\nMethods and measurementsWe performed the largest genome-wide association study undertaken for IPF susceptibility with a discovery stage comprising up to 2,668 IPF cases and 8,591 controls with replication in an additional 1,467 IPF cases and 11,874 controls. Polygenic risk scores were used to assess the collective effect of variants not reported as associated with IPF.\n\nMain resultsWe identified and replicated three new genome-wide significant (P<5x10-8) signals of association with IPF susceptibility (near KIF15, MAD1L1 and DEPTOR) and confirm associations at 11 previously reported loci. Polygenic risk score analyses showed that the combined effect of many thousands of as-yet unreported IPF risk variants contribute to IPF susceptibility.\n\nConclusionsNovel association signals support the importance of mTOR signalling in lung fibrosis and suggest a possible role of mitotic spindle-assembly genes in IPF susceptibility.

genomics↗

Biomarkers of collagen synthesis predict progression in the PROFILE idiopathic pulmonary fibrosis cohort

Idiopathic pulmonary fibrosis (IPF) is characterised by excessive extracellular matrix (ECM) deposition and remodelling. Measuring this activity provides an opportunity to develop tools capable of identifying individuals at-risk of progression. Longitudinal change in markers of ECM synthesis was assessed in 145 newly-diagnosed individuals with IPF. Serum levels of collagen synthesis neoepitopes, PRO-C3 and PRO-C6 (collagen type 3 and 6), were elevated in IPF compared with controls at baseline, and progressive disease versus stable disease during follow up, (PRO-C3 p<0.001; PRO-C6 p=0.029). Assessment of rate of change in neoepitope levels from baseline to 3 months (defined as slope to month 3: HIGH slope, slope > 0 vs. LOW slope, slope <=0) demonstrated no relationship with mortality for these markers (PRO-C3 (HR 1.62, p=0.080); PINP (HR 0.76, p=0.309); PRO-C6 (HR 1.14, p=0.628)). As previously reported, rising concentrations of collagen degradation markers C1M, C3M, C6M and CRPM were associated with an increased risk of overall mortality (HR=1.84, CI 1.03 - 3.27, p=0.038, HR=2.44, CI 1.39-4.31, p=0.002; HR= 2.19, CI 1.25-3.82, p=0.006; HR= 2.13 CI 1.21-3.75, p=0.009 respectively). Elevated levels of PRO-C3 and PRO-C6 associate with IPF disease progression. Collagen synthesis and degradation biomarkers have the potential to enhance clinical trials in IPF and may inform prognostic assessment and therapeutic decision making in the clinic.

clinical trials↗

Patient reported distress can aid clinical decision making in idiopathic pulmonary fibrosis: analysis of the PROFILE cohort

Idiopathic pulmonary fibrosis is a progressive and fatal interstitial lung disease. We aimed to determine if patient response to a palliative assessment survey could predict disease progression or death. We undertook a cross-sectional study in a UK clinical cohort of incident cases. Rasch-based methodology provided a disease distress value from an abridged 11 item model of the original 45 item survey. Distress values were compared with measures of lung function. Disease progression or mortality alone was predicted at twelve months from survey completion, with risk of death assessed at three, six and twelve months. Disease distress values were negatively correlated with lung function (r=-0.275 percent predicted DLCO). Expected survey scores computed from distress values could distinguish disease progression, 8.8 (p=0.004), and people who died, 10.2 (p=0.002), from those who did not progress, 6.9. Actual survey scores predicted disease progression and mortality with an area under the curve of 0.60 and 0.64, respectively. Each point increment in actual score increased risk of twelve-month mortality by 10%, almost 43% of people scoring above 18 did not survive beyond 105 days. We define a short questionnaire that can score disease distress and predict prognosis, assisting clinical decision making in progressive fibrosis.

clinical trials↗