Shao Zhifei, Makinde Toluwalope O, McGee Halvor S, Wang Xiang, Agrawal Devendra K
Department of Biomedical Sciences, Creighton University of School of Medicine, Omaha, NE 68178, USA.
J Immunol. 2009 Dec 1;183(11):7531-8. doi: 10.4049/jimmunol.0901341. Epub 2009 Nov 16.
Fms-like tyrosine kinase 3 ligand (Flt3L) reverses the features of allergic airway inflammation and increases a Th2-suppressive regulatory lung CD11c(high)CD11b(low) dendritic cell (DC) subset in a mouse model. We examined the migratory pattern and Ag uptake efficiency of lung DC subsets in the therapeutic effect of Flt3L. Lung CD11c(high)CD11b(low) and CD11c(low)CD11b(high) DCs from PBS-treated, OVA-sensitized, and Flt3L-treated/OVA-sensitized BALB/c mice were sorted using MACS and FACS for phenotype analysis. Lymphatic chemokine expression in thoracic lymph nodes was determined by immunohistochemistry. Migration of two lung DC subsets to lymphatic chemokines was examined in vitro using a Transwell chemotaxis assay. Labeled Ag was intranasally delivered into mouse lung to track the migration and Ag uptake of lung DCs. The in vitro cytokine secretion of mediastinal lymph node cells was determined using ELISA. CD11c(low)CD11b(high) DCs have higher expression of CCR5, CCR6, and CCR7, but lower expression of CCR2 than CD11c(high)CD11b(low) DCs. CD11c(low)CD11b(high) DCs in Flt3L-treated/OVA-sensitized mice demonstrated a less mature phenotype, inefficiency in Ag uptake, and impaired migration in vitro to lymphatic chemokine than those in OVA-sensitized mice. Administration of Flt3L decreased the expression of CCR5 and CCR7 in CD11c(low)CD11b(high) DCs in OVA-sensitized mice. Fewer Ag-carrying cells were detected in the lungs and lymph nodes in Flt3L-treated/OVA-sensitized mice than OVA-sensitized mice with a greater decrease in CD11c(low)CD11b(high) DCs. Mediastinal lymph node cells from Flt3L-treated mice secreted higher levels of Th1 cytokines and IL-10 than OVA-sensitized mice in vitro. In conclusion, Flt3L-generated lung immunogenic CD11c(low)CD11b(high) DCs have a less mature phenotype, impaired Ag uptake, and impaired migration to draining lymph nodes.
Fms样酪氨酸激酶3配体（Flt3L）可逆转过敏性气道炎症的特征，并增加小鼠模型中具有Th2抑制作用的调节性肺CD11c(高)CD11b(低)树突状细胞（DC）亚群。我们研究了肺DC亚群在Flt3L治疗作用中的迁移模式和抗原摄取效率。使用MACS和FACS对来自PBS处理、卵清蛋白（OVA）致敏以及Flt3L处理/OVA致敏的BALB/c小鼠的肺CD11c(高)CD11b(低)和CD11c(低)CD11b(高)DC进行分选，以进行表型分析。通过免疫组织化学测定胸段淋巴结中淋巴趋化因子的表达。使用Transwell趋化性分析在体外检测两个肺DC亚群向淋巴趋化因子的迁移。将标记的抗原经鼻递送至小鼠肺中，以追踪肺DC的迁移和抗原摄取。使用酶联免疫吸附测定（ELISA）测定纵隔淋巴结细胞的体外细胞因子分泌。与CD11c(高)CD11b(低)DC相比，CD11c(低)CD11b(高)DC具有更高的CCR5、CCR6和CCR7表达，但CCR2表达较低。与OVA致敏小鼠相比，Flt3L处理/OVA致敏小鼠中的CD11c(低)CD11b(高)DC表现出较不成熟的表型、抗原摄取效率低下以及体外向淋巴趋化因子的迁移受损。给予Flt3L可降低OVA致敏小鼠中CD11c(低)CD11b(高)DC中CCR5和CCR7的表达。与OVA致敏小鼠相比，在Flt3L处理/OVA致敏小鼠的肺和淋巴结中检测到的携带抗原的细胞更少，且CD11c(低)CD11b(高)DC的减少更为明显。在体外，来自Flt3L处理小鼠的纵隔淋巴结细胞分泌的Th1细胞因子和白细胞介素-10水平高于OVA致敏小鼠。总之，Flt3L产生的肺免疫原性CD11c(低)CD11b(高)DC具有较不成熟的表型、抗原摄取受损以及向引流淋巴结的迁移受损。
