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R M du Bois

Publications and source records attributed to R M du Bois.

At least 19 recordsLinked to original sources
PubMed2006

Expression of CCX CKR in pulmonary sarcoidosis.

OBJECTIVE: CCX CKR is a decoy chemokine receptor that specifically binds the chemokines CCL19, CCL25 and CCL21. CCL19 was previously found to be upregulated in pulmonary sarcoidosis. We have, therefore, investigated CCX CKR expression in this inflammatory disease. METHODS AND RESULTS: CCX CKR mRNA was semiquantitated using RT-PCR in unseparated bronchoalveolar (BAL) cells from sarcoidosis patients (S, n = 29) and healthy control subjects (C, n = 9). CCX CKR transcripts were upregulated in patients (mean +/- SEM); S, 0.82 +/- 0.10; C, 0.44 +/- 0.04; p = 0.01; this upregulation paralleled the disease course as assessed by the chest radiographic stage (p < 0.02). Immunocytochemistry localised the CCX CKR protein to ciliated bronchial cells. Flow cytometric fluorescent ligand uptake assay showed that these cells are able to internalize its ligand. CONCLUSION: These observations implicate CCX CKR in the modulation of the inflammatory response in sarcoidosis.

Bronchoalveolar Lavage Fluid↗
PubMed2006

A polymorphism in the promoter region of the CD86 (B7.2) gene is associated with systemic sclerosis.

Systemic sclerosis (SSc) is a connective tissue disease of unknown aetiology characterized by fibrosis of the skin and internal organs, vascular abnormalities and humoral autoimmunity. Strong T-cell-dependent autoantibody and HLA associations are found in SSc subsets. The co-stimulatory molecule, CD86, expressed by antigen-presenting cells, plays a crucial role in priming naïve lymphocytes. We hypothesized that SSc, or one of the disease subsets, could be associated with single-nucleotide polymorphisms of the CD86 gene. Using sequence specific primer-polymerase chain reaction (SSP-PCR) methodology, we assessed four CD86 polymorphisms in 221 patients with SSc and 227 healthy control subjects from the UK. Haplotypes were constructed by inference and confirmed using PHASE algorithm. We found a strong association between SSc and a specific haplotype (haplotype 5), which was more prevalent in patients than in controls (29% vs 15%, OR = 2.3, chi(2) = 12, P = 0.0005). This association could be attributed to the novel -3479 promoter polymorphism; a significant difference was observed in the distribution of the CD86 -3479 G allele in patients with SSc compared to controls (43.7% vs. 32.4%, OR = 1.7, chi(2) = 12.1, P = 0.0005). TRANSFAC analyses suggest that the CD86-3479T allele contains putative GATA and TBP sites, whereas G allele does not. We assessed the relative DNA protein-binding activity of the -3479 polymorphism in vitro using electromobility gel shift assays (EMSA), which showed that the -3479G allele has less binding affinity compared to the T allele for nuclear proteins. These findings highlight the importance of co-stimulatory pathways in SSc pathogenesis.

Algorithms↗
PubMed2005

Association of tumour necrosis factor-alpha, lymphotoxin-alpha and HLA-DRB1 gene polymorphisms with Löfgren's syndrome in Czech patients with sarcoidosis.

Sarcoidosis is a granulomatous disorder showing a clear association with MHC (HLA) class I and class II genes. In order to investigate whether polymorphisms of nearby pro-inflammatory genes located within the MHC class III region may also contribute to susceptibility to sarcoidosis or to its clinical manifestation, tumour necrosis factor-alpha (TNF-alpha) and lymphotoxin-alpha (LT-alpha) genes were chosen for analysis in a case-control association study. In order to evaluate the findings on the TNF-alpha and LT-alpha genes in connection with the closely linked MHC class II region, 'classical' HLA-DRB1 locus was also investigated. Polymerase chain reaction-based methodologies were used in order to characterize two single-nucleotide polymorphisms (TNF-308*G/A and LTAlpha+252*A/G) and HLA-DRB1 allele groups in 114 Czech patients with pulmonary sarcoidosis and 425 healthy controls. LTA+252*G and HLA-DRB1*13 allele carriers were more frequent in patients, compared to those in controls. By contrast, HLA-DRB1*07 carriers were less frequent among sarcoidosis patients. The overrepresentation of TNF-308*A, LTAlpha+252*G and HLA-DRB1*03 allele carriers was found in a subgroup of sarcoidosis patients presenting with Lofgren's syndrome (LS) by comparison with the subgroup of patients without LS (NLS; phenotype frequency LS vs NLS: 68.8 vs 37.1% for TNF-308*A, 93.8 vs 66.3% for LTA+252*G and 68.8 vs 21.3% for DRB1*03). The data suggest that the LTAlpha and HLA-DRB1 genes themselves or a gene located nearby contributes to the susceptibility to sarcoidosis and that TNF-308*A, LTA+252*G and HLA-DRB1*03 alleles are associated (directly or via linkage with unknown causative locus) with LS as a specific manifestation of the disease.

Adolescent↗
PubMed2005

Genetics of fibrosing lung diseases.

Genetic studies in familial lung fibrosis have demonstrated an association with surfactant protein C genes: two mutations have been found resulting in protein misfolding and causing type-II epithelial cell injury. Remarkably, different histological patterns were observed in the affected subjects, suggesting the influence of modifier genes and/or environmental factors. Surfactant protein C gene variations have not, however, been associated with sporadic cases, i.e. idiopathic pulmonary fibrosis (IPF). Susceptibility to IPF probably involves a combination of polymorphisms related to epithelial cell injury and abnormal wound healing. To date, the genetic associations with IPF that have been reported in different cohorts include the genes encoding tumour necrosis factor (TNF; -308 adenine), interleukin-1 receptor antagonist (+2018 thymidine) and association with severity and progression (interleukin-6/TNF receptor II and transforming growth factor-beta1 (TGFB1; +869 cytosine)), but none of these associations have been replicated by others. Unlike in IPF, immunological inflammation seems to be more prominent in the pathogenesis of scleroderma lung fibrosis, being an autoimmune disease with specific autoantibodies, such as antitopoisomerase antibodies, in patients with diffuse lung disease, and anticentromere antibodies, in patients with pulmonary vascular disease. Antitopoisomerase antibody positivity is associated with the carriage of human leukocyte antigen DRB1*11 and DPB1*1301 alleles, suggesting the recognition of a specific amino-acid motif. Extended haplotype analysis also supports the conclusion that TNF may be the primary association with anticentromere positivity. Intriguingly, associations with TGFB1 and genes involved in extracellular matrix homeostasis have been reported in this disease. In conclusion, significant steps forward have been taken in the understanding of the genetic contribution to fibrosing lung diseases, but major challenges lay ahead. It is the present authors' opinion that only a combined approach studying large numbers of familial and sporadic cases, all clinically well phenotyped, using multiple distinct cohorts, and genotyped according to relevant gene ontologies will be successful. It will be necessary to be particularly vigilant with regard to phenotype; the absence of very strong reproducible associations may be because of the rigidity of phenotype definition, coupled with the possibility that idiopathic pulmonary fibrosis may still be a heterogeneous group of diseases, despite the more rigid definition set out by the European Respiratory Society/American Thoracic Society statement.

Hermanski-Pudlak Syndrome↗
PubMed2004

Single-nucleotide polymorphisms in the SPARC gene are not associated with susceptibility to scleroderma.

OBJECTIVE: SPARC (secreted protein, acidic and rich in cysteine) is a matricellular protein that modulates cell-cell and cell-extracellular matrix interactions. SPARC expression is restricted mainly to sites of tissue remodelling and wound repair, and is prominent in fibrotic disorders. Single-nucleotide polymorphisms (SNPs) in the SPARC gene are reportedly linked to scleroderma in four ethnic groups: Choctaw Indians, Caucasians, African Americans and Mexican Americans. We set out to reproduce and to positionally clone these disease associations in a set of UK Caucasian scleroderma patients and ethnically matched controls. METHODS: One hundred and twenty-one scleroderma subjects and 200 controls were genotyped by polymerase chain reaction with sequence-specific primers differing only in the 3' nucleotide corresponding to each allele of the biallelic SNPs. Scleroderma patients were analysed against controls and on the basis of their fibrosing alveolitis status as judged by high-resolution computed tomography evaluation and the extent of cutaneous involvement. RESULTS: Eight biallelic SNPs were genotyped: three from the last untranslated exon, which had been described previously, and an additional five novel SNPs: two in the promoter region, one in exon three and two in the 3' untranslated region. Six major haplotypes were constructed across all eight SNP positions. No significant differences in genotype, allele or haplotype frequency were observed between scleroderma and controls or within scleroderma subgroups. CONCLUSIONS: SNPs in the SPARC gene are not associated with susceptibility to scleroderma. This research adds to the genetic knowledge of the SPARC gene by identifying five novel SNPs spanning the whole gene and inserting these within the context of clearly defined haplotypes.

Female↗
PubMed2004

No association between interleukin-18 gene polymorphisms and haplotypes in Dutch sarcoidosis patients.

Previously, an association between susceptibility to sarcoidosis and a polymorphism in the interleukin (IL-18) gene (IL-18 -607A/C) has been reported in Japanese. The aim of the present study was to validate this association in a clinically well-characterized population of Dutch Caucasians. Three other polymorphisms at positions -656, -137, and 1248 were included in order to extend the mapping of the IL-18 gene and to enable the construction of haplotypes. Polymorphisms were determined using sequence-specific primers (SSPs) and polymerase chain reaction (PCR). A total of 236 individuals was studied (133 patients and 103 controls). No significant differences were observed in the distribution of the -607 and the other polymorphisms between Dutch sarcoidosis patients and controls. However, significant differences in IL-18 -607 genotype and allele frequency distributions were found between the Dutch and the Japanese. From the investigated IL-18-promoter polymorphisms, we were able to deduce four haplotypes. No differences were observed in haplotype frequencies between Dutch sarcoidosis patients and controls. In conclusion, IL-18 polymorphisms do not appear to influence the susceptibility to sarcoidosis in Dutch Caucasians. Important differences in allele frequencies were observed between Japanese and Dutch sarcoidosis patients and controls.

DNA Primers↗
PubMed2004

Variations in histological patterns of interstitial pneumonia between connective tissue disorders and their relationship to prognosis.

AIMS AND METHODS: Pulmonary parenchymal disease is common in patients with connective tissue disorders (CTDs). However, most reports precede recognition of non-specific interstitial pneumonia (NSIP). We have therefore reviewed 54 lung biopsies from 37 patients with polymyositis/dermatomyositis (PM/DM) (n = 13), Sjögren's syndrome (n = 5), rheumatoid arthritis (n = 17) and systemic lupus erythematosus (SLE) (n = 2) to assess the overall and relative frequencies of patterns of interstitial pneumonia and their impact on prognosis. RESULTS AND CONCLUSIONS: NSIP was the most common pattern with an overall biopsy prevalence of 39% and patient prevalence of 41%. There was variation in prevalence between individual CTDs, with PM/DM commonly showing organizing pneumonia (n = 5), rheumatoid arthritis showing follicular bronchiolitis (n = 6) and Sjögren's syndrome showing chronic bronchiolitis (n = 4). These patterns presented either separately or in association with NSIP, occasionally with different patterns in biopsies from separate lobes. Only four patients showed a pattern of usual interstitial pneumonia (UIP): two with rheumatoid arthritis and one each with PM/DM and SLE. Overall mortality was 24%, the most frequently associated pattern being fibrotic NSIP (n = 5). In nine cases, pulmonary presentation preceded the systemic manifestation of the CTDs. When patients with CTDs present with chronic interstitial lung disease, the most common pattern is NSIP, although there is variation in pattern prevalence between individual disorders and patterns of interstitial pneumonia frequently overlap. These data suggest a different biology for intestitial pneumonias in CTDs when compared with the idiopathic interstitial pneumonias where UIP is the most common pattern. Mortality is similar to that seen in idiopathic NSIP and, coupled with pulmonary presentation occurring prior to the systemic manifestation of disease, this may have a bearing on the origin of some cases of putative idiopathic NSIP.

Adult↗
PubMed2004

Mapping of the immunodominant T cell epitopes of the protein topoisomerase I.

OBJECTIVES: To identify the immunodominant T cell epitopes of the topoisomerase I protein in patients with systemic sclerosis (SSc) and control subjects, using computational analysis software (TEPITOPE) and T cell proliferation assays. METHODS: Six oligopeptides, predicted by TEPITOPE software as potential topoisomerase protein epitopes, were used to perform T cell proliferation assays in 21 patients with SSc and 15 healthy controls. RESULTS: A positive response to at least one of the peptides was seen in 10/21 patients and 7/15 healthy controls. Among responders, the proliferative response was limited to a single peptide in 6/7 healthy controls, whereas 5/10 patients responded to more than one peptide. In responding patients a significant correlation was found between disease duration and number of peptides inducing a response (p = 0.007). CONCLUSIONS: Several T cell epitopes of the topoisomerase I protein have been identified and evidence has been found to suggest epitope spreading in patients with SSc.

Adult↗
PubMed2004

Genetic mutations in surfactant protein C are a rare cause of sporadic cases of IPF.

BACKGROUND: While idiopathic pulmonary fibrosis (IPF) is one of the most common forms of interstitial lung disease, the aetiology of IPF is poorly understood. Familial cases of pulmonary fibrosis suggest a genetic basis for some forms of the disease. Recent reports have linked genetic mutations in surfactant protein C (SFTPC) with familial forms of pulmonary fibrosis, including one large family in which a number of family members were diagnosed with usual interstitial pneumonitis (UIP), the pathological correlate to IPF. Because of this finding in familial cases of pulmonary fibrosis, we searched for SFTPC mutations in a cohort of sporadic cases of UIP and non-specific interstitial pneumonitis (NSIP). METHODS: The gene for SFTPC was sequenced in 89 patients diagnosed with UIP, 46 patients with NSIP, and 104 normal controls. RESULTS: Ten single nucleotide polymorphisms in the SFTPC sequence were found in IPF patients and not in controls. Only one of these created an exonic change resulting in a change in amino acid sequence. In this case, a T to C substitution resulted in a change in amino acid 73 of the precursor protein from isoleucine to threonine. Of the remaining polymorphisms, one was in the 5' UTR, two were exonic without predicted amino acid sequence changes, and six were intronic. One intronic mutation suggested a potential enhancement of a splicing site. CONCLUSIONS: Mutations in SFTPC are identified infrequently in this patient population. These findings indicate that SFTPC mutations do not contribute to the pathogenesis of IPF in the majority of sporadic cases.

Female↗
PubMed2003

Idiopathic pulmonary fibrosis/cryptogenic fibrosing alveolitis.

Idiopathic pulmonary fibrosis (IPF), synonymous with cryptogenic fibrosing alveolitis (CFA), is a progressive and usually fatal disease of unknown cause characterized by sequential acute lung injury with subsequent scarring and end-stage lung disease. Historically, IPF/CFA encompassed a heterogeneous group of different histological and clinical entities arising in an idiopathic setting. Recently, the American Thoracic Society (ATS) and European Respiratory Society (ERS) core committee has redefined diagnostic criteria for both IPF/CFAand idiopathic interstitial pneumonias confining the term IPF/CFA to patients with a histological pattern of usual interstitial pneumonia on lung biopsy. This review attempts to refine the clinico-radiological-pathological features that together define IPF/CFA as it is understood today, and to summarize the rationale of new therapeutic approaches based on the current understanding of the pathogenetic mechanisms.

Humans↗
PubMed2003

A single round PCR method for genotyping human surfactant protein (SP)-A1, SP-A2 and SP-D gene alleles.

The genes coding for the human surfactant proteins (SP)-A and SP-D are located on chromosome 10q22-q23.1. SP-D is the product of a single gene whereas SP-A is the product of two highly homologous genes SP-A1 and SP-A2. Several single nucleotide polymorphisms (SNP) are present in the SP-A1, SP-A2 and SP-D genes. Because of this high degree of sequence homology between the SP-A1 and SP-A2 genes, current genetic analysis studies employ a nested PCR/radioactive hybridization or restriction fragment length polymorphism approach to initially isolate the genes and subsequently to detect the SNP in these isolates. In this manuscript, we report the primers and conditions of a sequence specific primer-PCR methodology that enables the identification of SP-A1, SP-A2 and SP-D gene allelic variants directly on genomic DNA material.

Alleles↗
PubMed2003

Inhibitor kappa B-alpha (IkappaB-alpha) promoter polymorphisms in UK and Dutch sarcoidosis.

The aetiology of sarcoidosis is uncertain; current thinking implicates exposure of genetically susceptible hosts to environmental factors. The nuclear factor kappa B (NF-kappaB) family of transcription factors are critical regulators of immediate transcriptional responses in inflammatory situations and immune responses. Inhibitor kappa B-alpha (IkappaB-alpha) inhibits NF-kappaB and plays a major role in controlling its activity. We investigated IkappaB-alpha promoter polymorphisms using sequence-specific primer-polymerase chain reaction, at positions -881 (A/G), -826 (C/T), and -297 (C/T) in Caucasian sarcoidosis patients (UK and Dutch [NL]), each with their own controls. Disease severity at presentation was assigned using chest radiography and pulmonary function indices. In the combined populations, the -297T allele carriage was more prevalent in patients than in controls (P=0.008). Three common haplotypes were found, of which haplotype 2 (GTT) was significantly associated with sarcoidosis in comparison with control subjects (P=0.01). Subgroup analysis revealed that the -826T allelic carriage was most prevalent in stage II disease, and more prevalent in stage III than in stage IV (P=0.01). The -826T allelic carriage did not show any association with lung function. These results indicate that the NF-kappaB activation pathway might be associated with the inflammation of sarcoidosis.

Disease Progression↗
PubMed2003

Is there a role for microorganisms in the pathogenesis of sarcoidosis?

Sarcoidosis is a granulomatous disease that has the immunopathological features of being antigen-driven. It is a complex disease that appears to arise from the interaction of one or more triggers with an immunologically predisposed host. Previous reports of familial clustering and varying prevalence of sarcoidosis in different populations could reflect differences in ethnic predisposition or differences in local environmental exposures. This review focuses specifically on these areas that have been the subjects of intensive investigation recently. Specific focus is provided on the issue of an infective trigger and highlights popular candidates. It is concluded that microbes are a likely trigger (but not as an infection) in a genetically predisposed individual and that this initial event culminates in the sarcoidosis granulomatous response.

Bacterial Infections↗
PubMed2003

Genetics of pulmonary fibrosis.

Identifying genetic determinants of pulmonary fibrosis is at an early stage of evolution. It is now well recognized that "pulmonary fibrosis" covers a broad range of lung diseases including most topically the idiopathic interstitial pneumonias that have been classified recently. Additionally, it is recognized that the diffuse lung diseases of children that may progress to fibrosis are quite different from those of adults. Defining clinical phenotype is an absolute prerequisite to precise identification of genetic determinants, and this is at least part of the reason why we understand relatively little of these genetic determinants to date. In children, a number of mutations have been identified, particularly with regard to surfactant protein. In adults, families with idiopathic pulmonary fibrosis are being collected but there are no genetic data on these at this point. In sporadic disease, associations have been reported in early phase genes with disease predisposition and also, importantly, with disease severity: future studies will inevitably incorporate issues of severity of disease in analyses.

Journal Article↗
PubMed2003

BAL findings in idiopathic nonspecific interstitial pneumonia and usual interstitial pneumonia.

Idiopathic pulmonary fibrosis (IPF), which has the histological pattern of usual interstitial pneumonia (UIP), is a progressive interstitial lung disease with a poor prognosis. Idiopathic interstitial pneumonias with a histological pattern of nonspecific interstitial pneumonia (NSIP) have a better prognosis than UIP, and may present with a clinical picture identical to IPF. The authors hypothesised that bronchoalveolar lavage (BAL) findings may distinguish between UIP and NSIP, and have prognostic value within disease subgroups. BAL findings were studied retrospectively in 54 patients with histologically proven (surgical biopsy) idiopathic UIP (n=35) or fibrotic NSIP (n=19), all presenting clinically as IPF. These findings were also compared with the BAL profile of patients with other categories of idiopathic interstitial pneumonias. BAL total and differential cell counts did not differ between the two groups. Survival was better in NSIP. In neither group were BAL findings predictive of survival or changes in lung function at 1 yr, even after adjustment for disease severity, smoking and treatment. BAL differential counts in fibrotic NSIP differed from respiratory bronchiolitis-associated interstitial lung disease, but not from desquamative interstitial pneumonia or cellular NSIP. The authors conclude that bronchoalveolar lavage findings do not discriminate between usual interstitial pneumonia and nonspecific interstitial pneumonia in patients presenting with clinical features of idiopathic pulmonary fibrosis, and have no prognostic value, once the distinction between the two has been made histologically.

Bronchoalveolar Lavage↗
PubMed2002

The role of small airways in lung disease.

The small airways constitute one of the least understood areas of the lungs. They play a role in many lung diseases, and small airway pathology results in significant morbidity New approaches to their evaluation may provide insights into this major area of lung disease. Asthma is well recognized as a disease of both large and small airways. Physiological and pathological evidence, from techniques such as post-mortem tissue histological analysis, induced sputum and transbronchial biopsies, has reinforced the concept of the involvement of the entire bronchial tree n the inflammatory process in asthma, In addition to describing the airway pathology in asthma, th s review focuses on the pathogenesis and role of small airway obstruction n other diseases, including chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), sarcoidosis and obliterative bronchiolitis (OB). COPD is characterized by the presence of airflow obstruction resulting from lesions in the small airways. In addition, features compatible with small airways disease are common in IPF, sarcoidosis and OB. Recent advances in pulmonary imaging, such as high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) with hyperpolarized 3He, have allowed non-invasive reproducible measurements of structure-function relationships to be made for the small airways. These techniques have great potential for diagnosing changes in small airway function and for assessing responses to treatment. New insights into the contribution of small airways to a range of lung diseases may lead to the development of therapies targeted at this part of the bronchial anatomy.

Bronchi↗
PubMed2002

Single-cell analysis: a novel approach to tumour necrosis factor-alpha synthesis and secretion in sarcoidosis.

Tumour necrosis factor (TNF)-alpha is thought to be a key early cytokine in the pathogenesis of sarcoidosis, despite conflicting data. Largely the product of mononuclear phagocyte activation, it is unclear whether TNF-alpha production at disease sites is a feature of all mononuclear phagocytes that accumulate there or whether it is secreted by a subset of these cells. Using the reverse haemolytic plaque assay, the aims of this study were to determine if the upregulation of TNF-alpha could be confirmed and to investigate whether this was monocyte or macrophage specific. The reverse haemolytic plaque assay allows the measurement of cytokine production at a single cell level. A greater number of alveolar macrophages produced TNF-alpha compared to autologous monocytes in sarcoidosis but not in controls and, based on cell size, it was confirmed that this was the product of more mature macrophages and that the secretion of TNF-alpha by monocytes and macrophages was heterogeneous: not all monocytes and macrophages secrete TNF-alpha. No differences in the average levels of TNF-alpha secretion by peripheral blood monocytes or alveolar macrophages were observed. This study has demonstrated that a subset of mononuclear phagocytes, mature macrophages, are responsible for tumour necrosis factor secretion and this could have implications for targeted management in sarcoidosis in the future.

Adult↗