title: In vitro reactivation of human immunodeficiency virus-1 upon stimulation with scrub typhus rickettsial infection.
abstract: While a number of microbial infections induce a transient burst in viral load in individuals infected with human immunodeficiency virus-1 (HIV-1), a recent study has suggested that scrub typhus may suppress HIV-1 infection. We investigated the effects of Orientia tsutsugamushi on HIV-1 infection. In vitro HIV-1 infection experiments were conducted using peripheral blood mononuclear cells (PBMC) acutely infected with R5 and X4 HIV-1 or PBMC derived from patients receiving highly active antiretroviral therapy (HAART) whose plasma viral load was undetectable. Stimulation of PBMC with O. tsutsugamushi induced production of proinflammatory cytokines and beta-chemokines, and markedly down-regulated expression of CCR5. Although pretreatment with O. tsutsugamushi rendered PBMC resistant to R5 HIV-1, it otherwise enhanced HIV-1 replication. Stimulation by O. tsutsugamushi induced HIV-1 replication in PBMC from patients receiving HAART. These findings suggest that scrub typhus does not necessarily suppress HIV-1 infection and does have potential to enhance HIV-1 replication.
authors.affiliation: Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Moriuchi
authors.forename: Akira
authors.initials: A
authors.lastname: Tamura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Moriuchi
mesh_terms: D016207:Cytokines / Q000096:biosynthesis; D015536:Down-Regulation; D005434:Flow Cytometry; D015658:HIV Infections / Q000150:complications / Q000276:immunology; D016325:HIV Long Terminal Repeat / Q000502:physiology; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000382:microbiology* / Q000821:virology*; D012285:Orientia tsutsugamushi / Q000502:physiology*; D019713:Receptors, CCR5 / Q000378:metabolism; D012612:Scrub Typhus / Q000150:complications / Q000276:immunology; D015854:Up-Regulation; D014779:Virus Replication
chemical_list: D016207:Cytokines; D019713:Receptors, CCR5