Figure 3.

Constitutive expression of IL-5 from the squamous epithelium of L2-IL5 elicits the expansion of the eosinophilopoietic compartments of bone marrow and spleen, an increase in circulating eosinophil numbers and an oesophageal eosinophilia. Flow cytometric analysis in combination with fluorescence-activated cell sorting (FACS) was performed to identify and quantify the induced eosinophilia occurring in L2-IL5 mice. Regardless of the tissue/compartment examined eosinophils were identified through sequential gates initially focusing on forward versus side scatter before employing specific gates based on the presence/absence of unique cell surface markers (ie, CD45⁺, Ly6G⁻, MHCII^−/dim, SiglecF⁺). Therefore, eosinophils in (A) bone marrow, (B) spleen, (C) peripheral blood and (D) oesophagus were identified and quantified in 10-week-old L2-IL5 mice relative to wild-type controls. These cells were subsequently subjected to FACS and eventually cell differential analysis of DiffQuick (commercial Romanowsky) stained cytospin preparations of the sorted cell populations, identifying eosinophils in each of these compartments/tissues. These data are expressed as means±SEM of five to six individual mice per group. *p≤0.05 and ***p≤0.001. This figure is only reproduced in colour in the online version.