IL-15 is a novel growth factor for murine gamma delta T cells induced by Salmonella infection.
We have previously shown evidence for the early recruitment of gamma delta T cells during the disease course of primary infections with Listeria monocytogenes or Salmonella choleraesuis in mice. Since gamma delta T cells at this stage of the disease do not produce IL-2, the growth factor for the gamma delta T cells remains unknown. IL-15 is a novel cytokine that uses beta- and gamma-chain of IL-2R for signal transduction, and is produced by activated monocytes/macrophages. In this study, we investigated the proliferative activity of IL-15 for gamma delta T cells appearing after primary infection with S. choleraesuis 31N-1. The gamma delta T cells, which expressed beta- and gamma-chains of IL-2R, proliferated in the presence of rIL-15 and produced appreciable levels of gamma-IFN and IL-4. Addition of anti-IL-2R beta mAb significantly inhibited the IL-15-induced proliferation of the gamma delta T cells. Furthermore, the gamma delta T cells produced gamma-IFN in response to monocyte/macrophage cell line, J774A.1 infected with S. choleraesuis, which expressed an abundant level of IL-15 mRNA. This cytokine production was inhibited significantly by anti-IL-15 Ab. Taken together, these results suggest that IL-15 derived from infected macrophages may contribute to the early activation of gamma delta T cells during salmonellosis.
Laboratory of Host Defense and Germfree Life, Nagoya University School of Medicine, Japan.
H
H
Nishimura
K
K
Hiromatsu
N
N
Kobayashi
K H
KH
Grabstein
R
R
Paxton
K
K
Sugamura
J A
JA
Bluestone
Y
Y
Yoshikai
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D005260:Female; D007371:Interferon-gamma / Q000494:pharmacology; D019409:Interleukin-15; D007378:Interleukins / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D008264:Macrophages / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis / Q000187:drug effects / Q000502:physiology; D011994:Recombinant Proteins / Q000494:pharmacology; D012481:Salmonella Infections, Animal / Q000276:immunology*; D015398:Signal Transduction; D013047:Specific Pathogen-Free Organisms; D013268:Stimulation, Chemical; D016176:T-Lymphocyte Subsets / Q000187:drug effects* / Q000276:immunology
D019409:Interleukin-15; D007378:Interleukins; D016692:Receptors, Antigen, T-Cell, gamma-delta; D015375:Receptors, Interleukin-2; D011994:Recombinant Proteins; D007371:Interferon-gamma