1,066 research outputs found
Mycobacterium tuberculosis and human macrophage: the bacillus with "environment-sensing"
No full textMonocytes/macrophages in HIV infection and tuberculosis
No full textMycobacterium tuberculosis (MTB) and human immunodeficiency virus type 1 (HIV-1) are virulent intracellular pathogens that enter and replicate within macrophages, which represent their reservoire. Public health problems are greatly compounded when the two diseases co-exist, and this is the reason why Acquired Immunodeficiency Syndrome (AIDS) and tuberculosis (TB) have been termed "the cursed duet", given the synergistic effect they exert one each other. With the depression of immunity caused by HIV-1 infection, latent MTB infection is much more likely to progress to clinically significant disease. On the other hand, TB results in activation of T cells and macrophages that may harbor latent HIV. Here some data are reviewed that can contribute to clarify the mechanisms involved in the concurrent infection, given that MTB infection has been shown to be able to: a) enhance HIV-1 replication in macrophages, b) augment CC-CKR5 (CCR5) expression on macrophage membrane, and, c) induce apoptosis in a portion of infected macrophages
Asymmetric liposomes and uses in medical field thereof
No full textThe invention concerns new asymmetric liposomes and uses thereof in medicalfield transport lipids involved in antimicrobial or antiviral response, particularly at level of pulmonary target cells
Batimastat reduces Mycobacterium tuberculosis-induced apoptosis in macrophages
No full textIn this study, we report evidences that Mycobacterium tuberculosis (MTB)-induced apoptosis in macrophages is reduced by a broad-spectrum hydroxamic acid-based matrix metalloproteinase (MMP) inhibitor, Batimastat (BB-94). In particular, we show that BB-94 administration to MTB-infected macrophages inhibits apoptosis and the downmodulation of membrane CD14 expression. Moreover, the addition of broad spectrum matrix metalloproteinase inhibitor to cell culture, during MTB infection, decreases the release of soluble TNF-alpha and leads to a simultaneous increase of membrane TNF-alpha. These results show that MTB-induced apoptosis in macrophages is reduced by a MMP inhibitor and most probably is related to TNF-alpha release. This identifies BB-94 as a simultaneous anti-apoptotic and anti-inflammatory molecule during MTB infection
The presence of antibodies against HIV peptides in the sera of alloimmune mice and thalassemic patients is due to a polyclonal activation mechanism
No full textThis paper analyzes the HIV-1 gp120 epitope specificity and activation mechanisms (i.e., polyclonal versus oligoclonal) of antibodies present in the sera of alloimmune mice and humans. Sera from CBA mice engrafted with C57BL/6 lymphoid cells significantly reacted against the gp120-derived peptide aa 261-270, which shares high homology with the membrane-proximal domain of HLA class II beta-chains (HLA/gp120) and against the HIV gp120 V3 loop-derived peptides DP32 (HIV-1 MN-derived aa 302-334) and C53 (HIV-1 IIIB-derived aa 304-318). The same sera also reacted against the HIV-unrelated peptide necdin. Moreover, sera from BALB/c mice injected with LPS presented antibodies reacting against both HIV-related and -unrelated peptides, suggesting that similar mechanisms are shared in alloimmune and LPS-treated mice. A similar analysis was then performed on the sera of patients affected with beta-thalassemia major, receiving at least 10 blood transfusions/year. In particular, 15 of 58 (26%) sera from HIV-uninfected thalassemic patients showed a significantly reactivity against the HLA/gp120-derived peptides. Moreover, 22 of 58 (38%) sera from the same cohort showed a significant reactivity against DP32 peptide. This reactivity was related to a polyclonal activation mechanism since the DP32-reactive sera significantly bound a panel of HIV-unrelated peptides, as observed by testing 22 sera against necdin, 21 against HSP65 kDa, 21 against amyloid-1, and 17 against MAGE-1 peptides. Moreover, a significant increase of IgG concentration was also observed in all thalassemic sera, when compared to healthy controls, without regard to the anti-gp120 antibody reactivity. Taken together, these results indicate that (i) allogeneic stimuli may induce anti-gp120 antibodies in CBA and in 38% of polytransfused patients and (ii) this reactivity is related to a polyclonal activation mechanism but not to a heightened concentration of IgG. (C) 1997 Academic Press
Macrophage response to Mycobacterium tuberculosis during HIV infection: relationships between macrophage activation and apoptosis
No full textHuman macrophages represent the first line of defense for the containment of Mycobacterium tuberculosis infection. After phagocytosis, macrophages express activation surface markers and produce proinflammatory cytokines and chemokines whose main role is to control pathogen spreading by recruiting peripheral lymphocytes and monocytes at the site of inflammation. However, in the case of a concomitant human immunodeficiency virus (HIV) infection, these signals strongly enhance the susceptibility to viral infection both at the viral entry and replication levels. Under these conditions, viral expansion extends beyond tissue macrophages to T cells and vice-versa, according to the emerging viral phenotype. In absence of an efficient immune response, Mycobacterium tuberculosis can replicate in macrophages in an uncontrolled fashion culminating in macrophage death by apoptosis. As a consequence, a more severe form of immunedepression, involving both innate and specific immune responses, could be responsible for both ematogenous mycobacterial dissemination and extrapulmonary form of tuberculosis in HIV-infected patients
Mycobacterial 19-kDa lipoprotein mediates Mycobacterium tuberculosis-induced apoptosis in monocytes/macrophages at early stages of infection
No full textBillboards. Two projects by Maurizio Montagna
No full textArchitecture, city, device, time: all of these issues are taken into account by the Milanese photographer Maurizio Montagna. A keen interpretation of places in their anthropic and cultural transformation emerges from all his works. This article aims to focus on two different projects, Billboards 2008 and Billboards site-specific Latronico 2018, in which the author reflects on the relationship among the object, the subject and the context/landscape where they belong
Application of Bacteriophages for Human Health: An Old Approach against Contemporary “Bad Bugs”
No full textThe breadth of the antimicrobial resistance (AMR) problem exposes humankind to serious threats, which could lead, in the near future, to a worrisome raising of mortality and morbidity rates due to infections by “bad bugs” [...
CpG oligodeoxynucleotides promote phospholipase D dependent phagolysosome maturation and intracellular mycobacterial killing in M. tuberculosis infected type II alveolar epithelial cells
No full textCpG oligodeoxynucleotides have been previously shown to enhance antimycobacterial response in human monocytes/macrophages. The present study reports evidences showing the capability of CpG oligodeoxynucleotides to induce (i) host phospholipase D (PLD) activation, (ii) PLD dependent reactive oxygen intermediate production, (iii) PLD dependent phagolysosome maturation and (iv) PLD dependent intracellular mycobacterial killing in type II alveolar epithelial cells. These are the first evidences showing that alveolar epithelial cells may represent efficient effecter cells during primary innate antimycobacterial immune response
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