Gastrin-releasing peptide-like immunoreactive substance in bronchoalveolar lavage of idiopathic pulmonary fibrosis and sarcoidosis

The neuropeptide gastrin releasing peptide (GRP) is present in the lung, and functions as a modulator of tissue growth and repair in fibrotic processes, or as a modulator of cell movement and differentiation in various inflammatory processes, including granulomatous ones. In idiopathic pulmonary fibrosis (IPF), changes in the bronchoalveolar lavage (BAL) content of GRP can be expected. We measured GRP-like immunoreactive substances (GRP-IS) and another neuropeptide, vasoactive intestinal peptide (VIP)-IS in BAL by enzyme immunoassay. Our results showed a decrease in BAL GRP-IS in patients with IPF (26.5 +/- 5.5 pg.mg-1 protein) and sarcoidosis (35.9 +/- 9.2 pg.mg-1), compared to healthy nonsmokers (63.4 +/- 9.0 pg.mg-1). When data were expressed as pg.ml-1 BAL fluid recovered, a decrease was only seen in IPF, not in sarcoidosis. The levels of VIP-IS in BAL were not different between the groups studied. Increased protein levels in BAL had no correlation with the levels of GRP-IS or VIP-IS in BAL. Furthermore, BAL neutrophil percentages had no correlation with the levels of GRP-IS in BAL of patients with IPF. Using reversed phase high performance liquid chromatography (HPLC), several kinds of GRP-IS were detected in BAL. These findings suggest that the decreased level of GRP-IS in BAL may reflect a loss of GRP-producing cells due to chronic lung injury and fibrosis in patients with IPF.     

p59OASL, a 2'-5' oligoadenylate synthetase like protein: a novel human gene related to the 2'-5' oligoadenylate synthetase family

The 2'-5' oligoadenylate synthetases form a well conserved family of interferon induced proteins, presumably present throughout the mammalian class. Using the Expressed Sequence Tag databases, we have identified a novel member of this family. This protein, which we named p59 2'-5' oligoadenylate synthetase-like protein (p59OASL), shares a highly conserved N-terminal domain with the known forms of 2'-5' oligoadenylate synthetases, but differs completely in its C-terminal part. The C-terminus of p59OASL is formed of two domains of ubiquitin-like sequences. Here we present the characterisation of a full-length cDNA clone, the genomic sequence and the expression pattern of this gene. We have addressed the evolution of the 2'-5' oligoadenylate synthetase gene family, in the light of both this new member and new 2'-5' oligoadenylate synthetase sequence data from other species, which have recently appeared in the databases.     

Cyclophosphamide pulse therapy in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive disorder with poor prognosis. Response to treatment is infrequent and the use of immunosuppressive agents other than corticosteroids is the subject of ongoing discussion because of uncertain efficacy and side-effects. To determine the efficacy and safety of cyclophosphamide pulse therapy in IPF, this study retrospectively analysed 18 patients with progressive IPF who were treated with intermittent i.v. cyclophosphamide (1-13 g x month(-1)) and additional oral prednisolone for 1 yr. Static lung volumes, arterial oxygen tension (Pa,O2) at rest, clinical symptoms and potential treatment-related side-effects were recorded. Cyclophosphamide had to be stopped in one patient, owing to repeated pulmonary infection; 11 patients were responders (five improving, six stabilizing) and six patients deteriorated. The change in vital capacity (VC) of responders was +6.7+/-18.0% (mean +/-SD), compared with -20.6+/-18.2% in nonresponders (p=0.008). Pa,O2 remained constant in responders (+0.13+/-0.88 kPa (+1.0+/-6.6 mmHg)), while it decreased in nonresponders (-2.08+/-1.92 kPa (-15.6+/-14.4 mmHg, p=0.008)). Additional prednisolone was reduced by 19.1+/-13.4 mg in responders, compared with 6.7+/-16.3 mg in nonresponders (p=0.02). VC at initiation of therapy was higher in responders (60.2+/-10.2 versus 40.3+/-12.9% predicted; p=0.004). No side-effects occurred, other than respiratory tract infection. These data demonstrate that intravenous cyclophosphamide pulse therapy may be a favourable regimen for certain patients with progressive idiopathic pulmonary fibrosis. Patients with a vital capacity of more than 50% predicted and a shorter duration of disease may benefit most.     

Distribution of HLA antigens in idiopathic pulmonary fibrosis

Divergent observations suggest that genetic factors contribute to the susceptibility to or clinical course of idiopathic pulmonary fibrosis. To determine whether there is an association between the major histocompatibility (HLA) system and idiopathic pulmonary fibrosis, the distribution of 35 antigens of HLA loci A and B was determined among 33 white patients with idiopathic pulmonary fibrosis and 329 healthy white control subjects. Although certain antigens tended to be more prevalent among patients with idiopathic pulmonary fibrosis compared with control subjects, there were no significant differences in the phenotype frequencies of the HLA-A and HLA-B antigens between these 2 groups. Thus, although subtle associations may exist between the HLA loci and idiopathic pulmonary fibrosis, these results indicate that antigens of the HLA-A and HLA-B loci are not linked with major risk factors in this disease.     

Activity of the interferon-induced 2',5'-oligoadenylate synthetase in patients with chronic hepatitis C

The interferon-induced 2',5'-oligoadenylate synthetase (2-5OAS) is responsible, at least in part, for the antiviral state established in cells in response to viral infections. The purpose of this work was to study the relationship between hepatitis C virus (HCV) infection and 2-5OAS in patients with chronic hepatitis C. Peripheral blood mononuclear cells (PBMC) of 27 patients with chronic hepatitis C were investigated, as well as PBMC of 10 control subjects. Then, the patients were treated with 3 mu interferon-alpha 2a three times per week. At month 3 of therapy, PBMC were sampled. Of the total PBMC samples obtained, half were used for determination of in vivo 2-5OAS activity. The remaining cells were cultured for 24 h in either the absence or presence of 500 U/ml of interferon-alpha 2a for the determination of in vitro 2-5OAS activity. The mean basal in vivo 2-5OAS activities were 3.6 +/- 2.8 nmol/10(6) cells in patients versus 1.6 +/- 1.1 nmol/10(6) cells in controls (p < 0.01). Basal in vivo 2-5OAS activity did not correlate with mean HCV viremia, quantified by a "branched DNA"-based assay. Before treatment, interferon-alpha was detected in the serum of 2 patients in 27. After a 24 h culture of PBMC in the presence of interferon, in vitro 2-5OAS activity was significantly induced in the PBMC of both the patients and the controls. However, in vitro induction of 2-5OAS activity was significantly lower in the PBMC of the patients than in the PBMC of the controls (p < 0.01). At month 3 therapy, in vivo 2-5OAS activity was significantly induced (20.5 +/- 17.9; p < 0.0001). In vitro IFN inductions of 2-5OAS activity in PBMC before treatment and at month 3 of therapy were not significantly different. In conclusion, in vivo 2-5OAS activity is significantly induced in patients with chronic hepatitis C, but endogenously produced interferon-alpha does not seem to be involved. Chronic induction of 2-5OAS activity results in a decreased sensitivity of PBMC to exogenous interferon induction. Whether this phenomenon plays a role in the resistance of chronic hepatitis C to interferon therapy remains uncertain.     

Two patients with idiopathic pulmonary fibrosis and monoclonal gammopathy

A 67-year-old man and a 70-year-old man were admitted to our hospital because of dyspnea and dry coughing. Chest X-ray films showed bilateral reticulonodular shadows in the middle and lower lung fields. Specimens were obtained by open lung biopsies and the findings were compatible with those of usual interstitial pneumonia. Immunoelectrophoresis revealed monoclonal gammopathy in both patients. The levels of interleukin 6 in bronchoalveolar lavage fluid were high. In these two patients, idiopathic pulmonary fibrosis was associated with multiple myeloma and monoclonal gammopathy, and the levels of interleukin-6 in bronchoalveolar lavage fluid were high. These findings may help to elucidate the pathogenesis and development of idiopathic pulmonary fibrosis.     

Activation of 2'-5' oligoadenylate synthetase by single-stranded and double-stranded RNA aptamers

A number of small RNA molecules that are high affinity ligands for the 46-kDa form of human 2'-5' oligoadenylate synthetase have been identified by the SELEX method. Surface plasmon resonance analysis indicates that these RNAs bind to the enzyme with dissociation constants in the nanomolar range. Competition experiments indicate that the binding site for the small RNAs on the 2'-5' oligoadenylate synthetase molecule at least partially overlaps that for the synthetic double-stranded RNA, poly(I).poly(C). Several of the RNAs function as potent activators of 2'-5' oligoadenylate synthetase in vitro, although there is no correlation between binding affinity and ability to activate. The RNA aptamers having the strongest activation potential appear to have few base-paired regions. This suggests that 2'-5' oligoadenylate synthetase, which has previously been believed to be activated only by double-stranded RNA, can also be activated by RNA ligands with little secondary structure. Since 2'-5' oligoadenylate synthetase possesses no homology to other known RNA-binding proteins, the development of small specific ligands by SELEX should facilitate studies of RNA-protein interactions and may reveal novel features of the structure-function relationships involving this enzyme.     

Protein profile in bronchoalveolar lavage fluid from patients with sarcoidosis and idiopathic pulmonary fibrosis as revealed by SDS-PAGE electrophoresis and western blot analysis

So far bronchoalveolar lavage (BAL)-protein in interstitial lung disease (ILD) is evaluated by measuring concentrations of single proteins. Due to the high dilution of most proteins in BAL, analysis of protein profile has been disappointing. This study describes a new method to overcome this problem and to reveal a highly differentiated picture of BAL proteins. Eighteen patients with pulmonary sarcoidosis, 18 patients with idiopathic pulmonary fibrosis (IPF) and 22 patients with no clinical, roentgenologic or functional evidence of ILD underwent BAL. Total and differential cell count was performed. Normal values for the control group, a lymphocytic alveolitis in sarcoidosis and a granulocytic alveolitis in IPF-patients were found. Median total protein concentration in sarcoidosis showed an increase five times higher than that of the controls (150 mg 1(-1) and 27 mg 1(-1), respectively) with p < 0.001, IPF protein concentration (58 mg 1(-1)) exceeded twice the control values (0.01 > p > 0.001). Analysis of electrophoretic protein profile in controls with Western blot analysis and the biotin/streptavidin staining system revealed a highly differentiated range of bands. Staining with immunoglobulin antibody identified six bands. Four proteins with molecular weight < 21.000 dalton were present only in sarcoidosis patients. These proteins may be identical with fragmented serum proteins or different cell mediators detected in alveolar cell supernatants. Furthermore, in sarcoidosis the intensity and number of bands with molecular weight more than 67.000 dalton was increased. This gives strong evidence for an injury of the alveolar membrane integrity in the alveolitis during the course of sarcoidosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Enzymatic characteristics of recombinant medium isozyme of 2'-5' oligoadenylate synthetase

P69 is an isozyme of the medium size class of human 2'-5' oligoadenylate synthetases. In this study, recombinant P69 was expressed and used for enzymological and structural investigations. Bacterially expressed P69 was inactive whereas the same protein expressed in insect cells was highly active. Whether this difference could be due to differential post-translational modifications of the protein was investigated. Mutations of appropriate residues showed that myristoylation of the protein was not necessary for enzyme activity. In contrast, inhibition of glycosylation of P69, by tunicamycin treatment of the insect cells, produced an enzymatically inactive protein. Recombinant P69 produced in insect cells was purified by affinity chromatography. It was a dimeric glycoprotein, very stable and completely dependent on double stranded (ds) RNA for activity. The enzyme catalyzed the non-processive synthesis of 2'-5'-linked oligoadenylate products containing up to 30 residues. 2'-O-Methylated dsRNA was incapable of activating P69 and a 25-base pair dsRNA was as effective as larger dsRNA. This expression system will be useful for large scale production of P69 and its mutants for structural studies.     

替米沙坦联合糖皮质激素治疗特发性肺纤维化30例临床观察

目的:探讨替米沙坦联合泼尼松治疗特发性肺纤维化的临床疗效.方法:选取我院2008年1月～2010年1月收治的60例特发性肺纤维化病人的临床资料,随机分为治疗组(30例)和对照组(30例),对照组病人应用泼尼松治疗,治疗组病人在对照组治疗的基础上加用替米沙坦,连续治疗6个月,比较两组病人的临床疗效.结果:治疗组病人临床症状和肺功能改善优于对照组,两组病人比较差异有统计学意义(p＜0.05).结论:替米沙坦联合泼尼松治疗肺纤维化,能明显减轻病人的临床症状,改善肺功能,疗效满意值得在临床推广.     

Idiopathic nonspecific interstitial pneumonia/fibrosis: comparison with idiopathic pulmonary fibrosis and BOOP

Based on past difficulties in clinically differentiating patients with idiopathic pulmonary fibrosis (IPF), bronchiolitis obliterans-organizing pneumonia (BOOP), and nonspecific interstitial pneumonia/fibrosis (NSIP), which all manifest clinically as interstitial lung disease, experience with pathologically confirmed examples of the three diseases was reviewed to compare clinical profiles and prognosis and to define NSIP more clearly. Thirty-one patients (15 males and 16 females) were pathologically identified as NSIP and subclassified into either the cellular (n=16) or fibrotic group (n=15). All 31 patients were clinically considered to be idiopathic NSIP cases. Patients with idiopathic BOOP (n=16) and IPF (n=64) were compared with the NSIP patients. Subacute presentation of interstitial lung disease characterized both idiopathic NSIP and idiopathic BOOP. NSIP patients showed volume loss on a chest radiograph (29.0%) and honeycombing on a computed tomography scan (25.8%); these features were not found in BOOP patients. Bronchoalveolar lavage lymphocytosis was characteristic of both BOOP and NSIP. Two subgroups of NSIP can be recognized histologically: patients in the fibrotic group had a less favourable outcome than those in the cellular group. BOOP and NSIP had a more favourable outcome than IPF. In conclusion, idiopathic nonspecific interstitial pneumonia can be differentiated from other types of idiopathic interstitial pneumonia, both pathologically and clinically.     

Pneumocystis carinii in a patient with pulmonary sarcoidosis and idiopathic CD4+ T lymphocytopenia

A case of pulmonary sarcoidosis and idiopathic CD4+ T lymphocytopenia is reported. Pneumocystis carinii was detected in the bronchoalveolar lavage fluid of a young homosexual man who was asymptomatic without any evidence of congenital or acquired immunodeficiency but with a low CD4+ cell count. A clinical and histological diagnosis of pulmonary sarcoidosis was made. During follow up the patient had oral candidiasis and a CD4+ cell count persistently below 300/microliters. This case is highly suggestive of concurrent pulmonary sarcoidosis and idiopathic CD4+ T lymphocytopenia.     

The role of neutrophils in the pathogenesis of idiopathic pulmonary fibrosis

STUDY OBJECTIVES: The prognostic value of the neutrophil count in BAL fluid (BALF) has been controversial. The role of neutrophils in this inflammatory lung disease, therefore, was evaluated in this study by additional measures. MATERIALS AND METHODS: We performed BAL in 22 patients with idiopathic pulmonary fibrosis (IPF) diagnosed by open lung biopsy specimen. Percent polymorphonuclear leukocyte (PMN) in BALF and absolute neutrophil counts were compared with those of normal nonsmokers. Elastase complexed to alpha-1-proteinase inhibitor (alpha1-PI) in plasma and BALF was measured as a marker of elastase burden, and neutrophil distribution in 22 lung tissues was observed by immunohistochemistry using antineutrophil elastase antibody. RESULTS: Percent PMN and absolute neutrophil counts in BALF did not increase in patients with IPF as compared with normal nonsmokers (n=15); the plasma elastase-alpha1-PI complex value (mean+/-SE) of patients with IPF (668.5+/-112.4 ng/mL) was significantly high as compared with that of normal nonsmokers (130.3+/-21.3, p<0.001). In addition, the BALF elastase-alpha1-PI complex value (mean+/-SE) of patients with IPF was also significantly high (333.1+/-87.0 ng/mg albumin) as compared with that of normal nonsmokers (83.1+/-29.3 ng/mg albumin, p<0.05). Immunohistochemistry demonstrated considerable numbers of neutrophils infiltrating the lung parenchyma in biopsy specimens obtained by open lung biopsy. CONCLUSIONS: These results suggested that although the neutrophil count in BALF could not represent the distribution of neutrophil in the lung, high levels of neutrophil elastase were demonstrated in lung parenchyma and also in both BALF and sera. Therefore, neutrophils might indeed play an important role in the pathogenesis of IPF.     

2',5'-Oligoadenylates and related 2',5'-oligonucleotide analogues. 2. Effect on cellular proliferation, protein synthesis, and endoribonuclease activity

A number of the new enzymatically synthesized 2',5'-oligonucleotide trimers, namely, those containing the nucleosides 8-azaadenosine, toyocamycin, sangivamycin, formycin, 8-bromoadenosine, tubercidin, and guanosine, were found to inhibit protein synthesis and cellular proliferation after uptake into intact L and HeLa cells. 2',5'-Oligonucleotide trimers containing cytidine, inosine, uridine, and 1,N6-ethenoadenosine had some effect while those containing 2-chloroadenosine, 3-ribosyladenine, ribavirin, and 2-beta-D-ribofuranosylthiazole-4-carboxamide had no detectable effect on protein synthesis or cellular proliferation after uptake into L or HeLa cells. All of these 2',5'-oligonucleotide analogues inhibited protein synthesis in the in vitro rabbit reticulocyte lysate system except for the trimer containing ribavirin. Such nucleoside substitutions have further defined the substrate-specificity requirements for the endoribonuclease and/or the inhibitors for the 2',5'-phosphodiesterase. Most of the 2',5'-analogues were degraded in L-cell extracts so the endogenous nucleases are not very specific. The 2',5'-trimers containing tubercidin and 2-beta-D-ribofuranosylthiazole-4-carboxamide were quite stable in comparison to the 2',5'-A trimer. The inhibition of protein synthesis and cellular proliferation observed correlated well with the degradation of rRNA and polyadenylated mRNA observed after uptake of the 2',5'-analogues into intact L cells. The degradation of the polyadenylated mRNA appeared to be a more sensitive test than inhibition of cellular protein synthesis for determining biological activities of the 2',5'-oligonucleotide analogues.     

Production and purification of recombinant 2'-5' oligoadenylate synthetase and its mutants using the baculovirus system

Investigation of the structure-function relationship of the 2'-5' oligoadenylate [2-5 (A)] synthetases has been hampered by the lack of an efficient expression system for a recombinant enzyme. Here, we report that the 9-2 isozyme of murine 2-5 (A) synthetase can be efficiently expressed in insect cells using the baculovirus system. The recombinant protein was purified to apparent homogeneity, and its enzymatic activity was characterized. It had a high specific activity, required double-stranded RNA as a cofactor, and synthesized dimers to hexamers of 2-5 (A). The utility of our expression system was demonstrated by studying the properties of two previously reported mutant proteins. Both of these mutants, when produced in bacteria, are enzymatically inactive, although similarly produced wild-type protein is active. Unexpectedly, when expressed in insect cells, both mutant proteins were enzymatically as active as the wild-type protein. These results suggest that in the eukaryotic expression system described here, the mutant proteins can undergo appropriate modifications or folding that is required for attaining an enzymatically active conformation.     

Clinical evaluation of serum type IV collagen 7S in idiopathic pulmonary fibrosis

Type IV collagen is one of the major components of the basement membrane (BM). 7S domain (7S collagen) of type IV collagen is an N-terminal peptide which is stable against protease and heat. We investigated serum concentration of 7S collagen in patients with idiopathic pulmonary fibrosis (IPF) and other pulmonary diseases. The aim of this study was to evaluate whether changes in the serum concentration of 7S collagen reflect the fibrotic process of IPF. We measured the concentration of serum 7S collagen with radioimmunoassay in patients with IPF, chronic pulmonary emphysema (CPE), sarcoidosis, infectious pulmonary diseases (IPD) and normal healthy controls. We also monitored 7S collagen during the clinical course in some patients with IPF and investigated the correlation between the serum 7S collagen, and lactate dehydrogenase (LDH) and erthrocyte sedimentation rate (ESR) in patients with IPF. Patients with IPF showed significantly higher serum concentration of 7S collagen than other pulmonary diseases and healthy controls. The serum concentration of 7S collagen significantly decreased in IPF patients who showed roentgenographic improvement after corticosteroid treatment. There was a correlation between the serum 7S collagen and LDH, and ESR. In conclusion, serum concentrations of 7S collagen increase in patients with IPF. The measurement of 7S collagen is useful for the evaluation of fibrotic change in the lung.     

The 100-kDa 2',5'-oligoadenylate synthetase catalyzing preferentially the synthesis of dimeric pppA2'p5'A molecules is composed of three homologous domains

The 2-5A synthetases represent a family of proteins implicated in the mechanism of the antiviral action of interferon. When activated by double-stranded RNA, these proteins polymerize ATP into 2'-5'-linked oligomers with the general formula pppA(2'p5'A)n, n >/= 1. Three forms of human 2-5A synthetases have been described corresponding to proteins of 40/46 (p40/p46), 69/71 (p69/p71), and 100 kDa (p100). Here we describe the molecular cloning and characterization of p100. By screening a cDNA expression library with a specific p100 polyclonal antibody, we first isolated a 590-nucleotide cDNA fragment which was subsequently used to isolate the full-length 6365-nucleotide cDNA. This cDNA recognizes a distinct interferon-induced messenger RNA of 7 kilobases. It has an open reading frame encoding a protein of 1087 amino acids including the sequence of seven peptides obtained by microsequencing of the natural p100 protein, which was purified from interferon-treated human cells. p100 is composed of three adjacent domains, each homologous to the previously defined catalytic unit of 350 amino acids, which is present as one unit in p40/p46 and as two units in p69/p71. The recombinant p100 synthesized preferentially dimeric 2', 5'-oligoadenylate molecules and displayed parameters for maximum enzyme activity similar to the natural p100. These results confirm that the enzymatic activity of p100 is distinct compared with that of p40/p46 and p69/p71.