IL1R1 and inflammatory response: In another study, the role of crucial mediators of the Th2 response, signal transducer and activator of transcription 6 (STAT6), and interleukin-1 receptor 1 (IL-1R1) in MWCNT-induced lung inflammation and fibrosis was investigated in wild-type C57BL/6, IL-1R1 knockout (KO) or STAT6 (KO) mice exposed to 162 μg/mouse of Mitsui-7 via intratracheal administration.