FCGRT and bullous pemphigoid: Second, in antibody transfer models of pemphigus, bullous pemphigoid, EBA, or myasthenia gravis, FcRn‐ or β2 microglobulin‐deficient mice were completely or partly protected from induction of experimental disease (Li et al., 2005; Liu et al., 1997; Liu et al., 2007; Sesarman et al., 2008).