For example the effects on JNJ 7777120 in models of asthma, dermatitis, arthritis, pain, and peritonitis are consistent to those of other distinct H4R ligands and in H4R-deficient mice (Table 2; Thurmond et al., 2004, 2014a; Dunford et al., 2006; Coruzzi et al., 2007; Altenbach et al., 2008; Cowart et al., 2008; Liu et al., 2008; Cowden et al., 2010b, 2014; Hsieh et al., 2010; Shin et al., 2012; Savall et al., 2014). Here, HRH4 is linked to skin disorder.