Microparticles released by Listeria monocytogenes-infected macrophages are required for dendritic cell-elicited protective immunity.
Interplay between macrophages and dendritic cells in the processing and presentation of bacterial antigens for T-cell immune responses remains poorly understood. Using a Listeria monocytogenes (Lm) infection model, we demonstrate that dendritic cells (DCs) require the support of macrophages to elicit protective immunity against Lm infection. DCs themselves were inefficient at taking up Lm but capable of taking up microparticles (MPs) released by Lm-infected macrophages. These MPs transferred Lm antigens to DCs, allowing DCs to present Lm antigen to effector T cells. MP-mediated Lm antigen transfer required MHC class I participation, since MHC class I deficiency in macrophages resulted in a significant reduction of T-cell activation. Moreover, the vaccination of mice with MPs from Lm-infected macrophages produced strong protective immunity against Lm infection. We here identify an intrinsic antigen transfer program between macrophages and DCs during Lm infection, and emphasize that macrophages also play an essential role in DC-elicited Lm-specific T-cell responses.
Department of Biochemistry and Molecular Biology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Yi
Y
Zhang
Ruihua
R
Zhang
Huafeng
H
Zhang
Jing
J
Liu
Zhuoshun
Z
Yang
Pingwei
P
Xu
Wenqian
W
Cai
Geming
G
Lu
Miao
M
Cui
Reto A
RA
Schwendener
Huang-Zhong
HZ
Shi
Huabao
H
Xiong
Bo
B
Huang
D008841:Actin Cytoskeleton / Q000378:metabolism; D000818:Animals; D017951:Antigen Presentation / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D049109:Cell Proliferation; D055252:Cell-Derived Microparticles / Q000378:metabolism*; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D007109:Immunity / Q000276:immunology*; D008089:Listeria monocytogenes / Q000276:immunology*; D008088:Listeriosis / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control; D008264:Macrophages / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D013347:Subcellular Fractions / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology
D000942:Antigens, Bacterial