TY - JOUR
T1 - Listeria-infected myeloid dendritic cells produce IFN-β, priming T cell activation
AU - Feng, Hanping
AU - Zhang, Dong
AU - Palliser, Deborah
AU - Zhu, Pengcheng
AU - Cai, Shenghe
AU - Schlesinger, Ann
AU - Maliszewski, Laura
AU - Lieberman, Judy
PY - 2005/7/1
Y1 - 2005/7/1
N2 - The intracellular bacterium Listeria monocytogenes infects dendritic cells (DC) and other APCs and induces potent cell-mediated protective immunity. However, heat-killed bacteria fail to do so. This study explored whether DC differentially respond to live and killed Listeria and how this affects T cell activation. To control for bacterial number, a replication-deficient strain, Lmdd, defective in D-alanine biosynthesis, was used. We found that DC internalize both live and heat-killed Lmdd and similarly up-regulate the expression of costimulatory molecules, a necessary step for T cell activation. However, only live Lmdd-infected DC stimulate T cells to express the early activation marker CD69 and enhance T cell activation upon TCR engagement. Infection with live, but not heat-killed, Lmdd induces myeloid DC to secrete copious amounts of IFN-β, which requires bacterial cytosolic invasion. Exposure to high concentrations of IFN-β sensitizes naive T cells for Ag-dependent activation.
AB - The intracellular bacterium Listeria monocytogenes infects dendritic cells (DC) and other APCs and induces potent cell-mediated protective immunity. However, heat-killed bacteria fail to do so. This study explored whether DC differentially respond to live and killed Listeria and how this affects T cell activation. To control for bacterial number, a replication-deficient strain, Lmdd, defective in D-alanine biosynthesis, was used. We found that DC internalize both live and heat-killed Lmdd and similarly up-regulate the expression of costimulatory molecules, a necessary step for T cell activation. However, only live Lmdd-infected DC stimulate T cells to express the early activation marker CD69 and enhance T cell activation upon TCR engagement. Infection with live, but not heat-killed, Lmdd induces myeloid DC to secrete copious amounts of IFN-β, which requires bacterial cytosolic invasion. Exposure to high concentrations of IFN-β sensitizes naive T cells for Ag-dependent activation.
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U2 - 10.4049/jimmunol.175.1.421
DO - 10.4049/jimmunol.175.1.421
M3 - Article
C2 - 15972676
AN - SCOPUS:21244469755
SN - 0022-1767
VL - 175
SP - 421
EP - 432
JO - Journal of Immunology
JF - Journal of Immunology
IS - 1
ER -