title: Interferon-gamma therapy activates human monocytes for enhanced phagocytosis of Mycobacterium avium complex in HIV-infected individuals.
abstract: Defective immunological function of cells of the macrophage lineage contributes to the pathogenesis of HIV-1 infection. Because monocyte/macrophage function is enhanced by cytokines such as interferon-gamma (IFN-gamma), the use of this immunomodulator is of potential clinical interest as adjunctive immunotherapy in immunosuppressed individuals. In this study, we show that adjunctive IFN-gamma treatment in an HIV-infected individual with Mycobacterium avium complex (MAC) infection increased phagocytosis of MAC by blood monocytes when compared to cells from an HIV-infected patient who was receiving standard chemotherapy alone. Enhanced phagocytic efficiency resulting from IFN-gamma therapy was associated with increased surface expression of MHC II (HLA-DR), a phagocytic receptor (CD16), and the activation marker (CD69), although the levels of activation markers were dissimilar at baseline in the two participants. These results imply that IFN-gamma may be useful in restoring antimycobacterial function in immunosuppressed patients.
authors.affiliation: AIDS Pathogenesis Research Unit, Macfarlane Burnet Institute for Medical Research and Public Health, and Department of Medicine, Monash University, Melbourne, Victoria, Australia.
authors.forename: Katherine
authors.initials: K
authors.lastname: Kedzierska
authors.forename: Geza
authors.initials: G
authors.lastname: Paukovics
authors.forename: Amanda
authors.initials: A
authors.lastname: Handley
authors.forename: Marilyn
authors.initials: M
authors.lastname: Hewish
authors.forename: Jane
authors.initials: J
authors.lastname: Hocking
authors.forename: Paul U
authors.initials: PU
authors.lastname: Cameron
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Crowe
mesh_terms: D000998:Antiviral Agents / Q000008:administration & dosage*; D005434:Flow Cytometry; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D016867:Immunocompromised Host; D007371:Interferon-gamma / Q000008:administration & dosage*; D008262:Macrophage Activation / Q000187:drug effects; D015269:Mycobacterium avium Complex / Q000276:immunology*; D015270:Mycobacterium avium-intracellulare Infection / Q000188:drug therapy* / Q000276:immunology; D009894:Opportunistic Infections / Q000188:drug therapy* / Q000276:immunology; D010587:Phagocytosis / Q000187:drug effects*; D010865:Pilot Projects
chemical_list: D000998:Antiviral Agents; D007371:Interferon-gamma