Isoform 2 is a receptor for IL22. Binds to IL22, prevents interaction with the functional IL-22R complex and blocks the activity of IL22 (in vitro). May play an important role as an IL22 antagonist in the regulation of inflammatory responses. Isoform 1 may play a role in establishing and maintaining successful pregnancy. This is the function of IL22RA2 (interleukin 22 receptor subunit alpha 2, Ensembl gene identifier ENSG00000164485).