IL-33 promotes transcriptional and metabolic adaptations of tissue-resident Th2 cells

The polarization of naïve CD4 ⁺ T cells into Th2 cells is initiated in lymphoid organs and completed as the cells become tissue resident, where they express ST2, the receptor for the alarmin IL-33, which may be a key signal for tissue integration. Cellular metabolic requirements associated with this transition remain poorly understood. To address this, we compared the response of lymphoid tissue (LT) Th2 cells from helminth parasite-infected mice to stimulation by IL-33 versus through the T cell receptor via anti-CD3/CD28. We found that IL-33, but not anti-CD3/CD28, induced the development of tissue-resident like Th2 cells expressing ST2. This was associated with IL-33 induced changes in arginine metabolism linked to mTORC1 activation and polyamine synthesis, which were required for the development of tissue-resident like Th2 cells. Futhermore, IL-33 induced transcriptional changes in genes involved in chemotaxis and cell adhesion that may be critical for tissue integration. Our findings provide insights into adaptations of Th2 cells responding to tissue-integration cues.

IL-33 promotes development of tissue-resident-like Th2 cells in vitro from lymphoid tissue Th2 cells. This requires arginine-dependent mTORC1 activation and polyamine synthesis, and is marked by transcription of genes associated with chemotaxis and cell adhesion linked to tissue integration.