Attempts to elucidate reasons why mycobacterial infections are intractable, by using an experimental mouse infection model

• Published in: JAPANESE JOURNAL OF LEPROSY Vol. 65; no. 3; pp. 155 - 165
• Main Author: Tomioka, Haruaki
• Format: Journal Article
• Language: Japanese
• Published: Japan Japanese Leprosy Association 1996
• Subjects: Animals; Bactericidal mechanisms; Cytokines - physiology; Disease Models, Animal; Humans; Immunosuppressive macrophages; M. avium complex; Macrophages; Macrophages - immunology; Mice; Mycobacteria; Mycobacterium avium Complex - pathogenicity; Mycobacterium avium-intracellulare Infection - immunology; Mycobacterium avium-intracellulare Infection - microbiology; Mycobacterium tuberculosis - pathogenicity; Phagocytosis; Tuberculosis - immunology; Tuberculosis - microbiology
• ISSN: 1342-3681; 1884-314X
• DOI: 10.5025/hansen.65.155

This paper reviews some recent studies which have been performed by us and other investigators, in order to clarify the reason why most mycobacterial infections such as due to Mycobacterium tuberculosisand M. avium complex infections are intractable, that is, why these organisms can escape from attack by microbicidal mechanisms of host macrophages and consequently persist for long time at sites of infection. This paper mainly dealt with the two major subjects, which were studied by using an experimental model for murine M. avium infection. The first subject is on the modes and mechanisms of mycobacterial killing in host macrophages and the mechanisms of bacterial escape from an onslaught by macrophages. The second is on the characteristics of immunosuppressive macrophages induced in M. avium complex infection and the role of the suppressor macrophages in the establishment of immune unresponsiveness of host mice in the progressed stage of infection.