Figure 3. HDM exposed, neutrophil depleted mice exhibit augmented monocytosis, dendritic cell numbers and antigen presentation.

Balb/c mice were administered HDM or PBS intranasally (i.n.) 3 times per week for 1 week. At 24 hours prior to each HDM/PBS administration, mice were treated with either 100 μg of neutrophil depleting antibody, 1A8, or isotype control antibody, 2A3 intraperitoneally (i.p). At 24 hours post final HDM/PBS exposure, lung tissue was collected. (A) Lung monocyte subsets identified as Ly6C^low and Ly6C^high were enumerated by flow cytometry. (B) Numbers of lung monocyte-derived dendritic cells (moDCs) were also determined by flow cytometry. The number of moDCs (C) and CD86⁺ moDCs (D) in the mediastinal lymph nodes (MLN) were enumerated by flow cytometry. In some experiments, the final dose of HDM was admixed with 100 μg Alexa Fluor 488 labelled OVA (E) and mediastinal lymph nodes collected (Ŧ) at 24 hrs post the final HDM/PBS exposure. (F) The number of OVA⁺ moDCs within the mediastinal lymph nodes were enumerated by flow cytometry. Figures present data combined from 2 independent experiments with 4-6 mice per group for each experiment (A-D) or from 1 experiment with 5 mice per group (F). Results depicted as mean ± SEM. *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001 using Mann–Whitney statistical test.