Gene expression profiling of murine innate lymphoid cells. Mus musculus

Innate lymphoid cells (ILCs) are a recently recognized heterogenous group of immune cells that are critical in orchestrating immunity and inflammation in the intestine, but whether ILCs influence immune responses or tissue homeostasis at other mucosal sites remains poorly characterized. Here we identify a population of lung-resident ILCs in mice and humans that expressed the alloantigen Thy-1 (CD90), interleukin 2 (IL-2) receptor a-chain (CD25), IL-7 receptor a-chain (CD127) and the IL-33 receptor subunit T1-ST2. Notably, mouse ILCs accumulated in the lung after infection with influenza virus, and depletion of ILCs resulted in loss of airway epithelial integrity, diminished lung function and impaired airway remodeling. These defects were restored by administration of the lung ILC product amphiregulin. Collectively, our results demonstrate a critical role for lung ILCs in restoring airway epithelial integrity and tissue homeostasis after infection with influenza virus. As part of this study, we performed gene expression profiling to examine how the transcriptional signatures compared between murine naïve group 2 lung ILC and group 3 splenic LTi cell populations. Overall design: Group 2 ILCs from the lung (Lin- CD90+ CD25+ T1/ST2+) and Group 3 LTi cells from the spleen (Lin- CD90+ CD25+ CD4+) were sort-purified from naive wildtype C57BL/6 mice using BD FACS Aria. Four biological replicates were collected, each replicate containing 1.5 x 104 to 2 x104 cells sorted to a purity >97% from six pooled lungs (ILCs) or 10 pooled spleens (LTi cells). Cells were sorted directly into TRIzol LS (Invitrogen), then mRNA was isolated, amplified, labeled, and hybridized to Affymetrix GeneChip (Mouse Gene 1.0 ST).