Microglia and microglia-like cell differentiated from DC inhibit CD4 T cell proliferation.
The central nervous system (CNS) is generally regarded as a site of immune privilege, whether the antigen presenting cells (APCs) are involved in the immune homeostasis of the CNS is largely unknown. Microglia and DCs are major APCs in physiological and pathological conditions, respectively. In this work, primary microglia and microglia-like cells obtained by co-culturing mature dendritic cells with CNS endothelial cells in vitro were functional evaluated. We found that microglia not only cannot prime CD4 T cells but also inhibit mature DCs (maDCs) initiated CD4 T cells proliferation. More importantly, endothelia from the CNS can differentiate maDCs into microglia-like cells (MLCs), which possess similar phenotype and immune inhibitory function as microglia. Soluble factors including NO lie behind the suppression of CD4 T cell proliferation induced by both microglia and MLCs. All the data indicate that under physiological conditions, microglia play important roles in maintaining immune homeostasis of the CNS, whereas in a pathological situation, the infiltrated DCs can be educated by the local microenvironment and differentiate into MLCs with inhibitory function.
Bai
Bo
B
Department of Neurobiology, Taishan Medical College, Taian, Shandong Province, People's Republic of China.
Song
Wengang
W
Ji
Yewei
Y
Liu
Xi
X
Tian
Lei
L
Wang
Chao
C
Chen
Dongwei
D
Zhang
Xiaoning
X
Zhang
Minghui
M
D000818:Animals; D001921:Brain / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000378:metabolism; D002454:Cell Differentiation; D049109:Cell Proliferation; D002469:Cell Separation; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000166:cytology*; D042783:Endothelial Cells / Q000166:cytology; D005434:Flow Cytometry; D051379:Mice; D017628:Microglia / Q000378:metabolism*; D009569:Nitric Oxide / Q000737:chemistry / Q000378:metabolism; D010641:Phenotype; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis
D019408:Platelet Endothelial Cell Adhesion Molecule-1; D019010:Vascular Cell Adhesion Molecule-1; D009569:Nitric Oxide