Alberto Bisetti

Expression of CCR5 Is Increased in Human Monocyte-Derived Macrophages and Alveolar Macrophages in the Course of in Vivo and in Vitro Mycobacterium tuberculosis Infection

Human immunodeficiency virus (HIV) replicates more efficiently in Mycobacterium tuberculosis (MTB)-infected macrophages than in uninfected controls. We investigated whether this may be partly explained by changes in expression of CCR5 in the course of mycobacterial infection, as this molecule has been shown to be a coreceptor for HIV entry. Since the lung is the preferential organ of HIV replication in the course of tuberculosis, we preliminarily analyzed beta-chemokine receptor expression in alveolar macrophages from patients with active tuberculosis, using flow cytometry based on an MIP-1alpha ligand-biotin/avidin-FITC detection system. Increased MIP-1alpha receptor (MIP-1alphaR) expression in alveolar macrophages from infected patients was observed whereas no detectable expression could be revealed in uninfected controls. Since MIP-la can also bind CCR1 and CCR4, the presence of CCR5 mRNA was investigated in bronchoalveolar lavage (BAL) cells and detected in alveolar macrophages from tuberculosis patients only. The study was then extended to in vitro MTB-infected macrophages. Monocyte-derived macrophages (MDMs) were left to differentiate for 7 days before MTB H37Rv infection, and CCR5 expression was monitored, by using a specific monoclonal antibody, on days 1, 6, and 11 after infection. Increased CCR5 expression in MTB-infected macrophages was observed, with a peak on day 6 (64% in MTB-infected versus 33% in control cultures) and a decrease by day 11 (25% in MTB infected versus 13% in control cultures). These results show that CCR5 expression is enhanced in the course of in vitro MTB infection and during active pulmonary tuberculosis.

Mycobacterium tuberculosis—Induced Apoptosis in Monocytes/Macrophages: Early Membrane Modifications and Intracellular Mycobacterial Viability

Apoptosis has been observed in monocytes/macrophages in the course of in vivo and in vitro Mycobacterium tuberculosis (MTB) infection. In order to define the early events of MTB-induced apoptosis, membrane CD14 expression and the exposure of Annexin V-binding sites in MTB-infected monocytes/macrophages have been monitored. Moreover, the role of MTB-induced apoptosis was further analyzed in vitro in terms of mycobacterial viability. Results show that monocyte/macrophage apoptosis is a very early event that is strictly dependent on the MTB amount, and this apoptosis is associated with a selective down-regulation of surface CD14 expression. Furthermore, no statistically significant decrease in mycobacterial viability was observed, which indicates that the apoptotic pathway triggered by high doses of MTB is associated with parasite survival rather than with killing of the parasite.

Chronic obstructive pulmonary disease and associated patterns of memory decline.

The relationship between chronic obstructive pulmonary disease (COPD) and cognitive functioning was analyzed in a study with 50 aging patients. A complex pattern of interactions was identified between emotional and cognitive functioning and chronic respiratory disease when the effects of age, sex, type and severity of disease were controlled. These patients did not show any global and diffuse cognitive impairment. Only a portion of COPD patients (about 30%) evidenced memory impairment which was confined to immediate memory. Memory impairment found in these patients did not appear to be associated with those changes present in the aging process but was mainly related to those specific clinical and instrumental parameters which are considered valid indicators of respiratory efficiency. Two types of cognitive and emotional problems were identified. A progressive stage-dependent set of characteristics was associated with the course of the disease and a fluctuating, probably reversible state-dependent set of characteristics was associated with the temporary condition of the patients during the period of examination. Patients who had received more recent medical treatment or who were under protection of vaccination for influenza showed a better cognitive and emotional efficiency.

Discriminant analysis on small cell lung cancer and non-small cell lung cancer by means of NSE and CYFRA-21.1

A correct diagnosis of small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) is essential both for prognostic and therapeutic reasons. We used discriminant analysis as a method to optimize the discriminant power of serum tumour marker levels for differentiation between SCLC and NSCLC. A panel of serum markers, including neurone specific enolase (NSE), cytokeratin fragment antigen 21.1 (CYFRA-21.1), tissue polypeptide antigen (TPA) and carcinoembryonic antigen (CEA) was obtained in 50 consecutive NSCLC and 17 SCLC. Data were analysed by the BMDP statistical program after logarithmic transformation of marker levels. The variables selected were NSE and CYFRA-21.1. Considered together, they were able to give a 97% rate of correct classification. The formula generated (canonic variable, CV) was validated on a group of seven SCLC and 22 NSCLC patients. Only two errors occurred. We therefore conclude that the canonic variable tested, based on NSE and CYFRA-21.1, provides a good discrimination between the two types of lung cancer. The method is rapid, relatively inexpensive, and based on simple serum tests.

Expression of dopamine receptors in immune organs and circulating immune cells.

The existence of dopamine (DA) D1- and D2-like receptors in the rat and pigeon thymus and in human peripheral blood lymphocytes was investigated. The selective D1-like antagonist [3H]-SCH 23390 was used as a ligand of DA D1-like receptors (D1 and D5 sites). Pharmacological analysis suggests that binding of [3H]-SCH 23390 to sections of thymus and to human peripheral blood lymphocytes belongs mainly to the dopamine D5 receptor subtype. Light microscope autoradiography, performed in sections of rat and pigeon thymus, revealed that these receptors are located primarily in the cortical layer. DA D2-like receptors (D2, D3 and D4 sites) were studied in sections of rat thymus and in peripheral blood lymphocytes by using the putative DA D3 receptor agonist [3H]-7-OH-DPAT as a ligand. Both rat and pigeon thymus and human peripheral blood lymphocytes express a putative DA D3 receptor. These data are in agreement with recent molecular biology studies performed in human peripheral blood lymphocytes. The demonstration of different subtypes of DA receptors in a primary immune organ such as the thymus and in circulating immune cells supports the hypothesis of an involvement of DA in the control of immune function.

Malignant Mesothelioma in Subjects with Marfan’s Syndrome and Ehlers-Danlos Syndrome: Only an Apparent Association?

Malignant mesothelioma is a rare neoplasm which could be favored by an hereditary predisposing factor. So far, malignant mesothelioma have never been described in patients with hereditary diseases of the connective tissue. Here, we report some cases of mesothelioma affecting subjects who were not exposed to inhalation of asbestos. One of these subjects was affected by Ehlers-Danlos syndrome, whereas in two brothers, mesothelioma was associated with Marfan’s syndrome. The observation of the same histologic subtype of mesothelioma in two brothers and the coexistence of two pathologic conditions of mesodermal origin indicate the presence of hereditary factors predisposing to the cancerogenic action of even small amounts of asbestos. Structural alterations of collagen and primary immunodeficiency may represent the host factor inducing development of the neoplasm. We conclude that the association between these rare disorders of the connective tissue and mesothelioma may not be coincidental, but could be the result of the exposition to small amounts of asbestos in predisposed individuals.

Pharmacological characterisation of Ca2+ channels of the L-type in human peripheral blood lymphocytes.

Ca2+ channels of the L-type were characterised in intact human peripheral blood lymphocytes using a radioligand binding technique and the dihydropyridine-type Ca2+ channel antagonist [3H](+)-PN 200-110 (isopropyl-4-(2,1,3-benzoxadiazol-4-yl)1,4-dihydro-5-methoxycarbon yl-2, 6-dimethyl-3-pyridine carboxylate) as a ligand. [3H](+)-PN 200-110 binding to human peripheral blood lymphocytes was time-, temperature-, concentration-dependent and of high affinity. The dissociation constant (Kd) value was 0.4 +/- 0.02 nM and the maximum binding capacity (Bmax) was 33.5 +/- 1.6 fmol/10(6) cells. Pharmacological analysis of [3H](+)-PN 200-110 binding to human peripheral blood lymphocytes was consistent with the labelling of a Ca2+ channel of the L-type. In fact, dihydropyridine derivatives were the most potent competitors of [3H](+)-PN 200-110 binding, whereas phenylalkylamine and benzothiazepine compounds or non-selective Ca2+ channel modulators were weak or ineffective displacers. These findings are the first observation that human peripheral blood lymphocytes express Ca2+ channels of the L-type. The possibility that Ca2+ channel antagonists may interfere with immune system function is discussed.

Evaluation of response to chemotherapy in patients affected with non-small cell lung cancer by means of three tumour markers elaborated by discriminant analysis.

Chemotherapy is the most effective treatment for inoperable patients (70%) affected with non-small cell lung cancer (NSCLC). The early detection of tumour progression is mandative in order to promptly shift these patients towards salvage or supportive therapy. The present authors investigated the clinical value of a panel of tumour markers, elaborated by means of discriminant analysis, as a follow-up indicator for the detection of tumour progression. The serum levels of tissue polypeptide antigen (TPA), CYFRA-21.1, neuron-specific enolase (NSE) and carcino-embryonic antigen (CEA) were determined before chemotherapy and after three cycles of treatment. Discriminant analysis generated a formula (canonic variable) which correctly classified the 87.8% of the 74 subjects (86.1% of the 36 progressive diseases and 89.5% of 38 non-progressive diseases). This approach produces an algorithm able to calculate a progression score in NSCLC patients which can be helpful for following-up care and therapy control of these patients.

Age-related changes of the noradrenergic innervation of rat tracheo-bronchial tree and pulmonary vasculature.

Age-related changes of the noradrenergic innervation of the tracheo-bronchial tree and of pulmonary vasculature were investigated in male Wistar rats of 3 months (young), 12 months (adult) and 24 months (old/aged), using catecholamine histofluorescence techniques associated with image analysis and by high pressure liquid chromagraphy with electrochemical detection. In young rats, blue-green fluorescent nerve fibres supply tracheo-bronchial smooth muscle and tracheal and bronchial glands, which are innervated by a delicate network of nerve fibres rich in varicosities. Pulmonary artery and vein are sparsely innervated. They are supplied with nerve fibres distributed in the vasa vasorum or the adventitia and the outer tunica media. The higher noradrenaline concentrations were found in the trachea and extraparenchymal bronchi, followed by pulmonary vein and pulmonary artery. The density and pattern of noradrenergic innervation of the tracheo-bronchial tree, or of the pulmonary vasculature, were similar in young and adult rats. In aged rats, a loss of noradrenergic innervation involving primarily the supply to the smooth muscle of the tracheo-bronchial tree was observed. Histofluorescence techniques demonstrated a higher sensitivity than noradrenaline assay in detecting changes of the sympathetic innervation of the tracheo-bronchial tree and of the pulmonary vasculature. The possible significance of reduced noradrenergic innervation of the tracheo-bronchial tree in aged rats is discussed.

Evaluation of a novel tuberculosis complex-specific 34 kDa protein in the serological diagnosis of tuberculosis

Tuberculosis (TB) serological testing with antigen complexes, although very sensitive, is not always as specific due to reactive serum antibodies in patients with inactive TB or nontuberculous infections. Since the use of recombinant M. tuberculosis proteins may enhance specificity, this study was designed to evaluate a novel 34 kDa tuberculosis complex-specific protein as a component of an antigen panel of recombinant proteins. Seventy patients with active TB (41 positive and 29 negative for acid-fast bacilli (AFB) in sputum) were evaluated, in comparison with 30 tuberculin purified protein derivative skin test positive (PPD+) and 30 PPD- normals, 20 subjects with inactive TB and 20 PPD+ subjects with nontuberculous pneumonia as controls. Serum antibody levels were quantified using enzyme linked immunosorbent assay (ELISA) tests with MS2-34, a fusion protein comprising the NH2-terminal 16 kDa of the 34 kDa protein, a recombinant 38 kDa protein (p38), and PPD. Using MS2-34 and p38 as an antigen panel in active TB patients yielded higher sensitivity and negative predictive value (sensitivity 86%; negative predictive value 91%) than using PPD (sensitivity 66%; negative predictive value 81%). Importantly, the MS2-34+p38 panel yielded a higher sensitivity (83%) than PPD (66%) in the subset of AFB- active TB patients. Thus, this novel protein increases sensitivity and specificity of serological testing for TB when used in panels of recombinant proteins.