Interleukin-18 synthesis and secretion by dendritic cells are modulated by interaction with antigen-specific T cells.
We show that interleukin-18 is constitutively produced by dendritic cells; synthesis and secretion are poorly affected by maturative stimuli. Challenge of dendritic cells with autologous anti-tetanus toxoid T lymphocytes results in a secretory switch, with induction of secretion of biologically active interleukin-18 and decrease of its intracellular content. Similarly, when dendritic cells are challenged with allospecific T cells a dramatic decrease of intracellular interleukin-18 content occurs, whereas no effects are observed after co-culture with autologous activated T cells. The induction of secretion call be mediated by engagement of CD40 on dendritic cells, as indicated by the increased amount of interleukin-18 in dendritic cell supernatants after CD40 triggering by anti-CD40 antibodies. However, CD40 engagement, unlike from antigen-specific T cells, does not result in reduced intracellular interleukin-18 content, suggesting that this decrease may be mediated by structure(s) involved in antigen recognition.
Gardella
S
S
Laboratory of Clinical Pathology, National Institute for Cancer Research, Genova, Italy.
Andrei
C
C
Costigliolo
S
S
Poggi
A
A
Zocchi
M R
MR
Rubartelli
A
A
D017951:Antigen Presentation / Q000276:immunology; D019013:CD40 Antigens / Q000276:immunology; D002460:Cell Line; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D020382:Interleukin-18 / Q000096:biosynthesis* / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology*; D013745:Tetanus Toxoid / Q000276:immunology
D019013:CD40 Antigens; D020382:Interleukin-18; D013745:Tetanus Toxoid