Differential regulation of Type 1 and Type 2 mouse eosinophil activation by apoptotic cells

Purpose: We aimed to characterize the role of apoptotic cells in regulating eosinophils' response to diverse stimuli. Methods:Eosinophils were purified from the peritoneal cavity of Il5Tg mice and stimulated with IL-4 (i.e. type 2 activated eosinophils), IFN-γ, and a combination of lipopolysaccharide (LPS, i.e. type 1 activated eosinophils) and IFN-γ in the presence of apoptotic cells. Thereafter, RNA was obtained and the transcriptome signature following each stimulation was determined using RNA sequencing. Raw sequencing reads were trimmed and filtered using fastp, then aligned to mouse genome assembly (GRCm38) using STAR 2.7.2a. Normalization and differential expression analysis were performed in R 4.0.3 using the package DESeq2. Finally, gene ontology annotations were obtained from Ensembl and pathway graphs were obtained from KEGG. Results:RNAseq analysis revealed that apoptotic cells induce transcriptional changes in eosinophils and resulted in enrichment in pathways related to wounding and cell migration. Conclusion:RNAseq analysis of transcripts that were downregulated by apoptotic cells revealed that apoptotic cells inhibit pathways as defense responses and inflammatory responses and that apoptotic cells augmented eosinophils' response to IL-4. RNAseq of eosinophils following Type 1 and Type 2 activation in the presence of apoptotic cells