48 research outputs found
Relation between Skin Pharmacokinetics and Efficacy in AmBisome Treatment of Murine Cutaneous Leishmaniasis
AmBisome® (LAmB), a liposomal formulation of amphotericin B (AmB), is a second-line treatment for the parasitic skin disease cutaneous leishmaniasis (CL). Little is known about its tissue distribution and pharmacodynamics to inform clinical use in CL. Here, we compared the skin pharmacokinetics of LAmB with Fungizone® (DAmB), the deoxycholate form of AmB, in murine models of Leishmania major CL. Drug levels at the target site (the localized lesion) 48 hours after single intravenous (IV) dosing of the individual AmB formulations (1 mg/kg of body weight) were similar, but were 3-fold higher for LAmB than for DAmB on day 10 after multiple administrations (1 mg/kg on days 0, 2, 4, 6 and 8). After single and multiple dosing, intralesional concentrations were respectively 5- and 20-fold higher compared to those in the healthy control skin of the same infected mice. We then evaluated how drug levels in the lesion after LAmB treatment relate to therapeutic outcomes. After five administrations of the drug at 0, 6.25 or 12.5 mg/kg (IV), there was a clear correlation between dose level, intralesional AmB concentration and relative reduction in parasite load and lesion size (R2 values > 0.9). This study confirms the improved efficacy of the liposomal over the deoxycholate AmB formulation in experimental CL, which is related to higher intralesional drug accumulation
Quantification and role of innate lymphoid cell subsets in Chronic Obstructive Pulmonary Disease
Objectives
Innate lymphoid cells (ILCs) secrete cytokines, such as IFN-γ, IL-13 and IL-17, which are linked to chronic obstructive pulmonary disease (COPD). Here, we investigated the role of pulmonary ILCs in COPD pathogenesis.
Methods
Lung ILC subsets in COPD and control subjects were quantified using flow cytometry and associated with clinical parameters. Tissue localisation of ILC and T-cell subsets was determined by immunohistochemistry. Mice were exposed to air or cigarette smoke (CS) for 1, 4 or 24 weeks to investigate whether pulmonary ILC numbers and activation are altered and whether they contribute to CS-induced innate inflammatory responses.
Results
Quantification of lung ILC subsets demonstrated that ILC1 frequency in the total ILC population was elevated in COPD and was associated with smoking and severity of respiratory symptoms (COPD Assessment Test [CAT] score). All three ILC subsets localised near lymphoid aggregates in COPD. In the COPD mouse model, CS exposure in C57BL/6J mice increased ILC numbers at all time points, with relative increases in ILC1 in bronchoalveolar lavage (BAL) fluid. Importantly, CS exposure induced increases in neutrophils, monocytes and dendritic cells that remained elevated in Rag2/Il2rg-deficient mice that lack adaptive immune cells and ILCs. However, CS-induced CXCL1, IL-6, TNF-α and IFN-γ levels were reduced by ILC deficiency.
Conclusion
The ILC1 subset is increased in COPD patients and correlates with smoking and severity of respiratory symptoms. ILCs also increase upon CS exposure in C57BL/6J mice. In the absence of adaptive immunity, ILCs contribute to CS-induced pro-inflammatory mediator release, but are redundant in CS-induced innate inflammation
A microRNA-21-mediated SATB1/S100A9/NF-κB axis promotes chronic obstructive pulmonary disease pathogenesis.
[Figure: see text]
Emergence and spread of SARS-CoV-2 lineage B.1.620 with variant of concern-like mutations and deletions
Distinct SARS-CoV-2 lineages, discovered through various genomic surveillance initiatives, have emerged during the pandemic following unprecedented reductions in worldwide human mobility. We here describe a SARS-CoV-2 lineage - designated B.1.620 - discovered in Lithuania and carrying many mutations and deletions in the spike protein shared with widespread variants of concern (VOCs), including E484K, S477N and deletions HV69Delta, Y144Delta, and LLA241/243Delta. As well as documenting the suite of mutations this lineage carries, we also describe its potential to be resistant to neutralising antibodies, accompanying travel histories for a subset of European cases, evidence of local B.1.620 transmission in Europe with a focus on Lithuania, and significance of its prevalence in Central Africa owing to recent genome sequencing efforts there. We make a case for its likely Central African origin using advanced phylogeographic inference methodologies incorporating recorded travel histories of infected travellers
Chronic obstructive pulmonary disease and related phenotypes: polygenic risk scores in population-based and case-control cohorts
Background Genetic factors influence chronic obstructive pulmonary disease (COPD) risk, but the individual variants
that have been identified have small effects. We hypothesised that a polygenic risk score using additional variants
would predict COPD and associated phenotypes.
Methods We constructed a polygenic risk score using a genome-wide association study of lung function (FEV1 and
FEV1/forced vital capacity [FVC]) from the UK Biobank and SpiroMeta. We tested this polygenic risk score in nine
cohorts of multiple ethnicities for an association with moderate-to-severe COPD (defined as FEV1/FVC <0·7 and FEV1
<80% of predicted). Associations were tested using logistic regression models, adjusting for age, sex, height, smoking
pack-years, and principal components of genetic ancestry. We assessed predictive performance of models by area
under the curve. In a subset of studies, we also studied quantitative and qualitative CT imaging phenotypes that
reflect parenchymal and airway pathology, and patterns of reduced lung growth.
Findings The polygenic risk score was associated with COPD in European (odds ratio [OR] per SD 1·81
[95% CI 1·74–1·88] and non-European (1·42 [1·34–1·51]) populations. Compared with the first decile, the tenth decile
of the polygenic risk score was associated with COPD, with an OR of 7·99 (6·56–9·72) in European ancestry and
4·83 (3·45–6·77) in non-European ancestry cohorts. The polygenic risk score was superior to previously described
genetic risk scores and, when combined with clinical risk factors (ie, age, sex, and smoking pack-years), showed
improved prediction for COPD compared with a model comprising clinical risk factors alone (AUC 0·80 [0·79–0·81]
vs 0·76 [0·75–0·76]). The polygenic risk score was associated with CT imaging phenotypes, including wall area
percent, quantitative and qualitative measures of emphysema, local histogram emphysema patterns, and destructive
emphysema subtypes. The polygenic risk score was associated with a reduced lung growth pattern.
Interpretation A risk score comprised of genetic variants can identify a small subset of individuals at markedly
increased risk for moderate-to-severe COPD, emphysema subtyp
Genome wide association study of Preserved Ratio Impaired Spirometry (PRISm)
Background: Preserved Ratio Impaired Spirometry (PRISm) is defined as FEV1 <80% predicted, FEV1/FVC ≥0.70. PRISm is associated with respiratory symptoms and co-morbidities. Our objective was to discover novel genetic signals for PRISm and see if they provide insight into the pathogenesis of PRISm and associated co-morbidities.Methods: We undertook a genome-wide association study (GWAS) of PRISm in UK Biobank participants (Stage 1), and selected SNPs reaching genome-wide significance for replication in 13 cohorts (Stage 2). A combined meta-analysis of Stage 1 and Stage 2 was done to determine top SNPs. We used cross-trait Linkage Disequilibrium score regression to estimate genome-wide genetic correlation between PRISM and pulmonary and extra-pulmonary traits. Phenome-wide association studies of top SNPs was performed. Results: 22 signals reached significance in the joint meta-analysis, including four signals novel for lung function. A strong genome-wide genetic correlation (rg) between PRISm and spirometric COPD (rg = 0.62, p-value <0.001) was observed, and genetic correlation with type II diabetes (rg = 0.12, p-value 0.007). PheWAS showed that 18 of 22 signals were associated with diabetic traits and 7 with blood pressure traits.Discussion: This is the first GWAS to successfully identify SNPs associated with PRISm. Four of the signals; rs7652391 (nearest gene MECOM), rs9431040 (HLX), rs62018863 (TMEM114) and rs185937162 (HLA-B) have not been described in association with lung function before, demonstrating the utility of using different lung function phenotypes in GWAS. Genetic factors associated with PRISm are strongly correlated with risk of both other lung diseases and extra-pulmonary co-morbidity.<br/
Emergence and spread of SARS-CoV-2 lineage B.1.620 with variant of concern-like mutations and deletions.
Distinct SARS-CoV-2 lineages, discovered through various genomic surveillance initiatives, have emerged during the pandemic following unprecedented reductions in worldwide human mobility. We here describe a SARS-CoV-2 lineage - designated B.1.620 - discovered in Lithuania and carrying many mutations and deletions in the spike protein shared with widespread variants of concern (VOCs), including E484K, S477N and deletions HV69Δ, Y144Δ, and LLA241/243Δ. As well as documenting the suite of mutations this lineage carries, we also describe its potential to be resistant to neutralising antibodies, accompanying travel histories for a subset of European cases, evidence of local B.1.620 transmission in Europe with a focus on Lithuania, and significance of its prevalence in Central Africa owing to recent genome sequencing efforts there. We make a case for its likely Central African origin using advanced phylogeographic inference methodologies incorporating recorded travel histories of infected travellers
Chronic obstructive pulmonary disease and related phenotypes:polygenic risk scores in population-based and case-control cohorts
Author Correction: Multi-ancestry genome-wide association analyses improve resolution of genes and pathways influencing lung function and chronic obstructive pulmonary disease risk
Chronic obstructive pulmonary disease and related phenotypes: polygenic risk scores in population-based and case-control cohorts
Background:
Genetic factors influence chronic obstructive pulmonary disease
(COPD) risk, but the individual variants that have been identified have
small effects. We hypothesised that a polygenic risk score using
additional variants would predict COPD and associated phenotypes.
Methods:
We constructed a polygenic risk score using a genome-wide association study of lung function (FEV1 and FEV1/forced
vital capacity [FVC]) from the UK Biobank and SpiroMeta. We tested this
polygenic risk score in nine cohorts of multiple ethnicities for an
association with moderate-to-severe COPD (defined as FEV1/FVC 1
<80% of predicted). Associations were tested using logistic
regression models, adjusting for age, sex, height, smoking pack-years,
and principal components of genetic ancestry. We assessed predictive
performance of models by area under the curve. In a subset of studies,
we also studied quantitative and qualitative CT imaging phenotypes that
reflect parenchymal and airway pathology, and patterns of reduced lung
growth.
Findings:
The polygenic risk score was associated with COPD in European
(odds ratio [OR] per SD 1·81 [95% CI 1·74-1·88] and non-European (1·42
[1·34-1·51]) populations. Compared with the first decile, the tenth
decile of the polygenic risk score was associated with COPD, with an OR
of 7·99 (6·56-9·72) in European ancestry and 4·83 (3·45-6·77) in
non-European ancestry cohorts. The polygenic risk score was superior to
previously described genetic risk scores and, when combined with
clinical risk factors (ie, age, sex, and smoking pack-years), showed
improved prediction for COPD compared with a model comprising clinical
risk factors alone (AUC 0·80 [0·79-0·81] vs 0·76 [0·75-0·76]). The
polygenic risk score was associated with CT imaging phenotypes,
including wall area percent, quantitative and qualitative measures of
emphysema, local histogram emphysema patterns, and destructive emphysema
subtypes. The polygenic risk score was associated with a reduced lung
growth pattern.
Interpretation:
A risk score comprised of genetic variants can identify a small
subset of individuals at markedly increased risk for moderate-to-severe
COPD, emphysema subtypes associated with cigarette smoking, and patterns
of reduced lung growth.
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