CXCR2 and Sepsis: In addition, IL-1R2 expression is minimal in cluster 1 and 3 under health and sepsis condition (Figures 3A,B,E,F), which co-expressed with Fcgr1and Tim4 but lack of Cxcr2 (Supplementary Figures S3E–G), identified as resident tissue macrophages in the heart.