As expected, Th2-driven cytokines and related receptors (il-13, il-13ra2, il-4), chemokines (ccl11, ccl12 and ccl24), and genes associated with allergic diseases arginase 1 (arg1) and chitinase (chia1) (Woodruff et al., 2007; Lloyd and Hessel, 2010; Zhu, 2010) were also significantly upregulated in the HDM-challenged compared to allergen-naïve lungs (Table 1). The gene discussed is ARG1; the disease is allergic disease.