Phenotype and Functions of Brain Dendritic Cells Emerging During Chronic Infection of Mice with Toxoplasma gondii

摘要: During chronic infection of mice with Toxoplasma gondii , gene message for IL-12p40, CD86, and the potassium channel Kv1.3 was detected in brain mononuclear cells, suggesting presence dendritic cells (DC) CNS. Consistently, bearing DC markers CD11c 33D1 were localized at inflammatory sites infected brain. The number isolated + increased until peak inflammation. exhibited surface phenotype myeloid by coexpressing F4/80, little DEC-205, no CD8α. These mature, as indicated high-level expression MHC class II, CD40, CD54, CD80, CD86. They triggered Ag-specific primary allogeneic T cell responses very low APC/T ratios. Among from encephalitic brain, main producers IL-12. Evidence a parasite-dependent development CNS progenitors obtained vitro: after inoculation culture T. IL-12-secreting dendriform emerged, marker genes expressed. Different stimuli elicited generation maturation DC: neutralization parasite-induced GM-CSF prevented outgrowth concomitant release IL-12 production up-regulated external IFN-γ but stopped inhibiting parasite replication. GM-CSF-treated activated to secrete exposure lysate. In sum, these results demonstrate -induced expansion functional and, thus, highlight mechanism that may contribute chronicity host response.