Interleukin-13 receptor alpha 2 (IL13RA2), sometimes called Interleukin-13 binding protein (IL13BP) is a high affinity receptor for IL13 (Kd = 250 pmol/L) but is not sufficient to render cells responsive to IL13, even in the presence of IL4R (Donaldson et al. 1998). It is reported to exist in soluble form (Zhang et al. 1997); overexpression reduces STAT6 signaling (Kawakami et al. 2001). Its function may be to prevent IL13 signaling via the functional IL4R:IL13RA1 cell surface receptor. IL13BP is overexpressed in some human cancers and enhances cell invasion (Joshi & Puri 2012).