Interleukin-18 stimulates HIV-1 replication in a T-cell line.
Interleukin-18 (IL-18) is a recently identified proinflammatory cytokine. Its ability to induce interferon-g suggests a potential virustatic effect. On the other hand, it stimulates NFkB - an activator of HIV replication. Recently, stimulation of HIV-1 in monocytic cells has been demonstrated. In the present study, the influence of IL-18 on HIV-1 replication in lymphatic cells was investigated. Hut78 cells were infected with HIV-1 in the presence of recombinant human IL-18 expressed either in E. coli or eucaryotically by baculovirus in Sf9 cells. HIV-1 replication was monitored by p24 ELISA and endpoint titration of culture supernatants on C8166 cells. The addition of IL-18 led to a 3- to 15-fold enhancement of HIV replication in Hut78 cells. By addition of neutralising monoclonal anti-IL-18 antibodies, this effect of IL-18 was reduced by 75%. Exposure of Hut78 to IL-18 prior to HIV infection could exclude the possibility that IL-18 promotes infection of cells. Taken together, these data provide direct evidence for an IL-18-mediated enhancement of HIV-1 replication in lymphatic cells.
Klein
S A
SA
Universitätsklinik Frankfurt, Medizinische Klinik III, Theodor-Stern-Kai 7, D-60590 Frankfurt, Germany.
Klebba
C
C
Kauschat
D
D
Pape
M
M
Ozmen
L
L
Hoelzer
D
D
Ottmann
O G
OG
Kalina
U
U
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D017931:DNA Primers; D004926:Escherichia coli; D016655:HIV Core Protein p24 / Q000096:biosynthesis; D015497:HIV-1 / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D020382:Interleukin-18 / Q000494:pharmacology*; D007700:Kinetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000494:pharmacology; D018411:Spodoptera; D013601:T-Lymphocytes; D014162:Transfection; D014779:Virus Replication / Q000187:drug effects*
D017931:DNA Primers; D016655:HIV Core Protein p24; D020382:Interleukin-18; D011994:Recombinant Proteins