J. Exp. Med. https://doi.org/10.1084/jem.20172359 (2018)

Group 2 innate lymphoid cells (ILC2s) are dependent on the transcription factor GATA-3 and produce the cytokines IL-5 and IL-13 after being activated. In The Journal of Experimental Medicine, Lei et al. show that signaling via the adhesion molecule ICAM-1 regulates ILC2 development and function. Icam1–/– mice generate fewer ILC2s and develop less-severe allergic responses than those of wild-type mice. Icam1–/– ILC2s produce less IL-5 and IL-13 in vitro, suggestive of a cell-intrinsic defect. Ligation of ICAM-1 by the integrin LFA-1 triggers activation of the kinase Erk, which stabilizes GATA-3 protein. Loss of ICAM-1 thus results in destabilization of GATA-3 and diminished GATA-3-dependent transcriptional responses. These findings suggest that interfering with ICAM-1–LFA-1 might ameliorate allergic responses.