Transcriptional profiling of eosinophil subsets in Interleukin-5 transgenic mice

Eosinophils are important in fighting parasitic infections and are implicated in the pathogenesis of asthma and allergy. Interleukin-5 (IL-5) is a critical regulator of eosinophil development, controlling proliferation, differentiation and maturation of the lineage. Mice that constitutively express IL-5 have more than 10 fold more eosinophils in the haematopoietic organs than their wild type counterparts. We have identified that much of this expansion is in a population of Siglec-F high eosinophils, which are rare in wild type mice. In this study we assessed transcription in myeloid progenitors, eosinophil precursors and Siglec-F medium and Siglec-F high eosinophils from IL-5 transgenic mice and in doing so have created a useful resource for eosinophil biologists. We have then utilised these populations to construct an eosinophil trajectory based on gene expression and to identify gene sets that are associated with eosinophil lineage progression. Cell cycle genes were significantly associated with the trajectory, and we experimentally demonstrate an increasing trend towards quiescence along the trajectory. Additionally we found gene expression changes associated with constitutive IL-5 signalling in eosinophil progenitors, many of which were not observed in eosinophils.

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