Experimentally, EHV-1 and EHV-4 infections could be tested in cell lines from susceptible species, e.g., bovine, rabbit, monkey, pig, cat, human (Studdert and Blackney, 1979; Ahn et al., 2010), alpacas, lamas, polar bears (Greenwood et al., 2012), and rhinoceros (Greenwood et al., 2012; Abdelgawad et al., 2014, 2015) cell lines, with and without inhibited MHC-I expression by using β2m knockdown as in Sasaki et al. (2011). Here, B2M is linked to infection.