Regulatory eosinophils triggered by innate lymphoid cells type 2 during asthma induce resolution of chronic arthritis

Eosinophils possess distinct functions, being pro-inflammatory in asthma and worm infection on the one hand, while supporting resolution of inflammation and tissue repair on the other hand. We could demonstrate that the immunological pathways causing asthma in the lungs at the same time elicit resolution of arthritis in the joints in an eosinophil-dependent manner. It can be hypothesized that the pro-inflammatory action of eosinophils in the lungs and their homeostatic functions in the synovium are mediated by tissue-specific functional priming. Therefore, single cell RNA sequencing (scRNA-seq) was used to investigate whether distinct eosinophil subsets arise in the lungs and the joints of mice upon combined asthma/arthritis model. Overall design: Single cell mRNA sequencing of sorted CD45+CD11b+Sigec-F+ granulocytes of lung and synovial tissue from mice with eosinophilic asthma (OVA), K/BxN serum-induced arthritis (SIA) and a comination of asthma and arthritis (OVA+SIA) at day 7 post-SIA