title: Apoptosis of human monocytes/macrophages in Mycobacterium tuberculosis infection.
abstract: Tuberculosis (TB) is still a major health problem, both as a single disease entity and as a cofactor in AIDS. The interaction between macrophage and Mycobacterium tuberculosis (MTB) is a critical step in the establishment of an early chronic infection. This study analyses the capacity of MTB to induce apoptosis in cells obtained by broncho-alveolar lavage (BAL) from patients with reactive pulmonary tuberculosis and from AIDS patients with disseminated pulmonary tuberculosis. Apoptosis was increased three-fold in BAL cells obtained from patients with pulmonary tuberculosis and even more markedly in alveolar macrophages of MTB-infected AIDS patients, compared with controls. Apoptosis was analysed and characterized by propidium iodide (PI) incorporation, terminal deoxy transferase (TDT)-mediated dUTP-biotin nick end labelling (TUNEL), and tissue transglutaminase (tTG) expression. The MTB-macrophage interaction was also investigated in vitro by infecting monocyte-derived macrophages (MDM) with MTB (virulent strain H37Rv). The induction of apoptosis by MTB required viable bacteria, was dose-dependent, and was restricted to H37Rv. Infection with either Mycobacterium avium complex (MAC) or HIV-1 and treatment with heat-killed MTB failed to induce apoptosis.
authors.affiliation: Department of Biology University of Rome Tor Vergata, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Placido
authors.forename: G
authors.initials: G
authors.lastname: Mancino
authors.forename: A
authors.initials: A
authors.lastname: Amendola
authors.forename: F
authors.initials: F
authors.lastname: Mariani
authors.forename: S
authors.initials: S
authors.lastname: Vendetti
authors.forename: M
authors.initials: M
authors.lastname: Piacentini
authors.forename: A
authors.initials: A
authors.lastname: Sanduzzi
authors.forename: M L
authors.initials: ML
authors.lastname: Bocchino
authors.forename: M
authors.initials: M
authors.lastname: Zembala
authors.forename: V
authors.initials: V
authors.lastname: Colizzi
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000201:enzymology / Q000473:pathology*; D000328:Adult; D017209:Apoptosis; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D018929:Cell Culture Techniques; D005260:Female; D006801:Humans; D008264:Macrophages / Q000201:enzymology / Q000473:pathology*; D016676:Macrophages, Alveolar / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000473:pathology*; D011503:Transglutaminases / Q000378:metabolism; D014397:Tuberculosis, Pulmonary / Q000201:enzymology / Q000473:pathology*
chemical_list: D011503:Transglutaminases