IL1RL1 and asthma: However, OS biomarkers NO2−, lipid peroxide, protein sulfhydrils, and inflammatory biomarkers TNFα, IL-4, IL-37, IL-1β, IL-1RL1, IL-1R1, NLRP3, and TGF-β1 showed positive association with asthma in nonsmokers, but not in smokers.