TSLP neutralization inhibits surface marker expression on airway CD11c+ cells.

(A) Lung cell suspensions from mice were stained with combinations of PerCP-Cy 5.5-conjugated CD11c, PE-conjugated OX40L, FITC-conjugated CD80 and APC-conjugated CD86. The dead cells and the debris were excluded based on forward scatter (FSC)/side scatter (SSC) plots. (B) A total of 1×10⁵ to 3×10⁵ viable cells were acquired using FACS, and the DCs were then sorted as CD11c+ airway cells on FSC/SSC plots. (C) Mice that were chronically exposed to HDM received an intranasal administration of anti-TSLP mAb or of a control IgG 60 minutes prior to each HDM exposure. The expression levels of OX40L, CD80 and CD86 on pulmonary DCs were then analyzed using flow cytometry. The HDM-exposed mice exhibited a significant increase in the OX40L, CD80 and CD86 surface markers on CD11c+ airway cells. However, anti-TSLP pretreatment effectively reduced OX40L, CD80 and CD86 expression on the DCs, even though the mice were continuously exposed to HDM. (D) The TSLP levels in the BALF were highly correlated with OX40L expression on CD11c+ airway cells in all of the treatment mice (n = 20, R = 0.879, p<0.01). (E) Representative data from one of the five replicates. (F) Staining for OX40L (12-4031), CD80 (11-4888), and CD86 (17-4321) from isotype-Ig-treated controls. The data represent the means±SEM (n = 5). * p<0.05 or ** p<0.01 compared with the HDM group. ^# p<0.05 or ^## p<0.01 compared with the IgG-treated control mice. The results are derived from 4 experimental groups (5 mice/per group), and the data are representative of 5 independent experiment.