One of the major differences between Kato et al.’s published study and ours is that Kato et al. used human recombinant IL-33 and human IL-33–neutralizing antibody and tested their efficacy in a BALB/c mouse model of endometriosis, whereas we used mouse recombinant IL-33 and mouse IL-33–neutralizing antibody in our mouse model. Here, IL33 is linked to endometriosis.