Irini Lambiri

Biomarkers in COPD

Chronic Obstructive Pulmonary Disease is characterized by an abnormal inflammatory response of the lungs to noxious particles and gases, caused primarily by cigarette smoking. Although COPD affects the lung, it also produces significant systemic consequences. Inflammation, proteases-antiproteases imbalance, oxidative stress, tissue damage and tissue repair, apoptosis and several genes seem to be involved in the pathogenesis of the disease. The cellular and molecular events underlying COPD pathogenesis are driven by multifunctional molecules including enzymes, cytokines, chemokines, growth factors, lipid mediators and their respective receptors. A large number of biomarkers evaluated in COPD, showed a high degree of redundancy. Nevertheless, current understanding of the pathobiology of COPD suggests a number of biomarkers as potential candidates. The development of relevant markers of lung damage, pulmonary inflammation, and systemic disease will be essential to our further understanding of the natural history of COPD and the discovery of new, effective treatments for its progression. This review summarizes recent findings, on potential pulmonary biomarkers in the induced sputum, the exhaled air condensate, the peripheral blood, the urine, the bronchoalveolar lavage fluid, and in selective cases, in bronchial biopsies.

Active Remodeling in Idiopathic Interstitial Pneumonias: Evaluation of Collagen Types XII and XIV

Fibril-associated collagens with interrupted triple helices (FACITs) XII and XIV act as fibril organizers and assist in the maintenance of uniform fibril size. We investigated the spatial expression patterns of collagens XII and XIV in cryptogenic organizing pneumonia (COP)/organizing pneumonia (OP) and in idiopathic pulmonary fibrosis (IPF)/usual interstitial pneumonia (UIP) and compared them to normal human lung. Study subjects included 10 patients with COP/OP, 10 patients with IPF/UIP, and 8 control subjects. Immunostaining for collagens XII and XIV was carried out in paraffin-embedded human lung tissue sections. Picrosirius red histochemical staining for collagen I expression and electron microcopy to evaluate fibril diameter were also performed. In normal lung, collagens XII and XIV were expressed in perivascular and subpleural connective tissue. In COP/OP, both collagens showed intense staining in perivascular connective tissue, thickened alveolar septae, and subpleural areas. In IPF/UIP, XII and XIV were expressed in perivascular connective tissue, in areas of established fibrosis, and in areas of subpleural thickening. Only collagen XII was expressed in granulation tissue plugs in COP/OP and in fibroblastic foci in IPF/UIP. Collagen type I was overexpressed in fibrotic areas. Electron micrographs revealed obvious fibril diameter alteration and fusion in the same areas. FACITs XII and XIV are expressed in normal and fibrotic lung. Unlike collagen XIV, collagen XII was expressed in granulation tissue plugs in COP/OP and in fibroblast foci in IPF/UIP. This may suggest a possible distinct role for both collagens in the modulation of the extracellular matrix during the onset of fibrotic process.

Differential telomerase expression in idiopathic pulmonary fibrosis and non-small cell lung cancer

Telomerase is a reverse transcriptase ribonucleo-protein (h-TERT) that synthesizes telomeric repeats using its RNA component (h-TERC) as a template. Telomerase dysfunction has been associated with both fibrogenesis and carcinogenesis. In this study, we aimed to evaluate the telomerase mRNA expression levels of both subunits (h-TERT and h-TERC) in lung tissue and bronchoalveolar lavage fluid (BALF) from patients with idiopathic pulmonary fibrosis (IPF) and non-small cell lung cancer (NSCLC), since there are indications of common pathogenetic pathways in these diseases. We prospectively examined lung tissue samples from 29 patients with IPF, 10 patients with NSCLC and 21 controls. Furthermore, we examined BALF samples from 31 patients with NSCLC, 23 patients with IPF and 12 control subjects. The mRNA expression for both h-TERT and h-TERC was measured by real-time RT-PCR. In the lung tissue samples, both h-TERT and h-TERC mRNA expression levels varied among the 3 groups (p=0.036 and p=0.002, respectively). h-TERT mRNA levels in the patients with IPF were lower compared with those in the controls (p=0.009) and patients with NSCLC (p=0.004). h-TERC mRNA levels in the patients with IPF were lower compared with those in the controls (p=0.0005) and patients with NSCLC (p=0.0004). In the BALF samples, h-TERT mRNA expression levels varied among the groups (p=0.012). More specifically, h-TERT mRNA levels in the patients with IPF were higher compared with those in the controls (p=0.03) and patients with NSCLC (p=0.007). The attenuation of telomerase gene expression in IPF in comparison to lung cancer suggests a differential role of this regulatory gene in fibrogenesis and carcinogenesis. Further functional studies are required in order to further elucidate the role of telomerase in these devastating diseases.

A 35 year old smoker with shortness of breath

A previously well 35 year old man who currently smoked cigarettes (40 pack years) was referred because of a history of dyspnoea on exertion that had gradually got worse during the two months before presentation and a cough that was initially productive but then dry. He regularly smoked crack cocaine and took cocaine intranasally. At presentation he had hypoxaemia (partial pressure of oxygen 57 mm Hg), with a respiratory rate of 20 breaths/min. Physical examination showed only bilateral fine inspiratory crackles at the middle and lower zones of the chest. Initial blood tests were unremarkable. He had no signs of collagen tissue disorder, his autoantibody profile was negative, and HIV screening was negative. Chest radiography showed a bilateral reticular pattern at the middle and lower zones and bilateral infiltrates in the lower zones of the lung. Pulmonary function testing showed a restrictive pattern (total lung capacity 49%, forced expiratory volume in one second 48%, forced vital capacity 47%, diffusing capacity of the lung for carbon monoxide 36%). A 12 lead resting electrocardiogram showed sinus rhythm and an echocardiogram showed no abnormalities and no indirect evidence of pulmonary hypertension. Baseline saturation was 96% with a heart rate of 100 beats/min. During the six minute walking distance test he desaturated to 83% after three minutes and having completed 110 m. He underwent high resolution computed tomography of the chest (figs 1 and 2⇓ ⇓). Fig 1 High resolution computed tomography of the chest: upper lung zones Fig 2 High resolution computed tomography of the chest: lower lung zones