T-helper cell type-1 transcription factor T-bet is upregulated in pulmonary sarcoidosis.

Upregulation of genes for interferon (IFN)-γ and CXC chemokine receptor (CXCR)3 expression, two crucial molecules in sarcoid inflammation and granuloma formation, is directly controlled by the T-helper (Th)1 transcription factor T-bet (T-box, expressed in T-cells). However, there is no information on T-bet expression in sarcoidosis or its relationship with "sarcoidosis-associated" genes. Therefore, we investigated expression of T-bet mRNA and, in parallel, a spectrum of genes known to be involved in sarcoidosis pathogenesis. Transcripts were determined in bronchoalveolar lavage (BAL) cells from 62 sarcoidosis patients and 25 controls by quantitative RT-PCR; T-bet protein was localised by immunohistochemistry. Patient's BAL cells expressed higher mRNA T-bet levels than those of controls (mean ± sd fold change 3.64 ± 1.72; p = 0.00006). T-bet mRNA expression did not vary between clinical phenotypes as assessed by chest radiography stage, presence/absence of Löfgren's syndrome, extrapulmonary/pulmonary involvement or progressing/remitting disease (p > 0.05). T-bet mRNA expression correlated with expression of IFN-γ, CC chemokine ligand 5, CXC chemokine ligand (CXC)10, interleukin (IL)-2 receptor/IL-15 receptor ß, CXCR3 and CXCR6 (p < 0.01). T-bet protein was localised to alveolar macrophages and lymphocytes, tissue multinucleated giant cells, macrophages and lymphocytes. In pulmonary sarcoidosis, T-bet upregulation is associated with changes in expression of IFN-γ, CXCR3 and chemokines/receptors involved in the pathogenesis of sarcoidosis, which suggests a role for T-bet in this Th1 disease, including modulation of some sarcoidosis-associated genes.

The CR1 C5507G polymorphism is not involved in susceptibility to idiopathic pulmonary fibrosis in two European populations.

Idiopathic pulmonary fibrosis (IPF), a severe lung disease with unknown aetiology, is thought to have an important genetic component. Single nucleotide polymorphism, C5507G, of the complement receptor 1 (CR1) gene, which affects the number of CR1 molecules on erythrocytes, has been associated with susceptibility to IPF in a single European population. To replicate this finding, 53 Czech IPF patients with 203 Czech healthy control subjects and 70 English IPF patients with 149 English controls were investigated. In both populations, there were no significant differences in distribution of CR1 C5507G variants between IPF patients and their appropriate control groups. In conclusion, the association of the CR1 C5507G polymorphism with susceptibility to IPF was not reproducible in Czech and English populations.

[Pulmonary alveolar proteinosis]. / Plicní alveolární proteinóza.

Pulmonary alveolar proteinosis is a rare disease characterised by excessive accumulation of surfactant components in the alveoli and the distal airways with minimum inflammatory reaction and fibrosis of pulmonary interstitium. Three clinical forms of pulmonary alveolar proteinosis are distinguished - congenital, primary and secondary. Results of ultrastructural, biochemical and functional analyses and studies performed on genetically modified mice support the presumption that accumulation of surfactant in pulmonary alveolar proteinosis is a result of a degradation disorder and of diminished clearance of the surfactant from the alveolar space rather than of excessive synthesis of surfactant components. Over the last 15 years, significant discoveries have been made which have helped to clarify the etiology and pathogenesis of the disease. A number of gene mutations have been discovered which lead to the development of congenital pulmonary proteinosis. Apart from impaired surfactant protein function, a key role in the development of pulmonary alveolar proteinosis is played by the signal pathway of granulocyte and macrophage colonies stimulating growth factor (GM-CSF) which is necessary for the functioning of alveolar macrophages and for surfactant homeostasis. The role of GM-CSF has been proven especially in primary pulmonary alveolar proteinosis which is currently considered an auto-immune disease involving the development of GM-CSF neutralising autoantibodies. In most cases, the prognosis for the disease in adult patients is good, even though there is a 10 to 15% rate of patients who develop respiratory failure. Total pulmonary lavage is considered to be the standard method of treatment. In recent years, recombinant human GM-CSF has been studied as a prospective therapy for the treatment of pulmonary alveolar proteinosis.

CC chemokine receptor 5 and interleukin-1 receptor antagonist gene polymorphisms in patients with primary Sjögren's syndrome.

OBJECTIVE: Interleukin-1 receptor antagonist (IL-1Ra) and also mononuclear cell-attractant chemokines CCL3, CCL4 and CCL5 have been implicated in the immunopathogenesis of primary Sjögren syndrome (pSS). Both the gene coding for receptor CCR5 binding the aforementioned CCL ligands and the gene for IL-1Ra are polymorphic. We have therefore in a case control study assessed the putative role of these "candidate" polymorphic genes in the inflammatory process in Sjögren syndrome. METHODS: DNA was obtained from 39 unrelated patients with primary Sjögren's syndrome and 76 unrelated healthy controls; all subjects were Caucasians of Slovak origin. CCR5 delta 32 and IL-1Ra VNTR polymorphisms were genotyped by PCR-SSP. RESULTS: The frequencies of CCR5 delta 32 in patients with pSS were different from that in control subjects: there was an apparent decrease of the mutant allele in the patient group. CCR5 delta 32/CCR5 heterozygosity was associated with a reduced relative risk of pSS (OR 0.35, p = 0.043). There was no difference in the distribution of the alleles of the IL-1Ra VNTR polymorphism between the groups of pSS patients and control subjects. CONCLUSION: In this population of patients with Sjögren's syndrome, the frequency of CCR5 delta 32/CCR5 genotype is significantly decreased. The data suggests that carrier status for the CCR5 delta 32 allele may contribute to protection from the development of primary Sjögren's syndrome. In contrast, IL-1Ra VNTR polymorphism does not confer susceptibility to primary Sjögren's syndrome in Slovak Caucasians.

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.