Sensory neuronal STAT3 is critical for IL-31 receptor expression and inflammatory itch

Sonoko Takahashi ¹¹³, Sotaro Ochiai ¹¹⁰¹³ Jianshi Jin ²¹¹, Noriko Takahashi ¹, Susumu Toshima ¹³, Harumichi Ishigame ¹¹², Kenji Kabashima ⁴⁵, Masato Kubo ⁶⁷, Manabu Nakayama ⁸, Katsuyuki Shiroguchi ², Takaharu Okada ¹⁹¹⁴

https://doi.org/10.1016/j.celrep.2023.113433

Highlights

• Sensory neuronal IL-31RA and STAT3 are essential for IL-31-induced itch
• STAT3 is important for expression and downstream signaling of IL-31 receptor
• IL-31 enhances GPCR-induced itch transmitted by multiple sensory neuronal subsets
• Sensory neuronal STAT3 contributes to IL-31-independent inflammatory itch

Summary

IL-31 receptor blockade suppresses pruritus of atopic dermatitis. However, cell-type-specific contributions of IL-31 receptor to itch, its expression mechanism, and the downstream signaling pathway to induce itch remain unknown. Here, using conditional knockout mice, we demonstrate that IL-31-induced itch requires sensory neuronal IL-31 receptor and STAT3. We find that IL-31 receptor expression is dependent on STAT3 in sensory neurons. In addition, pharmacological experiments suggest that STAT3 activation is important for the itch-inducing signaling downstream of the IL-31 receptor. A cutaneous IL-31 injection induces the nuclear accumulation of activated STAT3 first in sensory neurons that abundantly express IL-31 receptor and then in other itch-transmitting neurons. IL-31 enhances itch induced by various pruritogens including even chloroquine. Finally, pruritus associated with dermatitis is partially dependent on sensory neuronal IL-31 receptor and strongly on sensory neuronal STAT3. Thus, sensory neuronal STAT3 is essential for IL-31-induced itch and further contributes to IL-31-independent inflammatory itch.