Few clinical trials have been conducted to address the potential benefit of AAT therapy for conditions unrelated to inherited AAT deficiency, such as islet and lung transplantation, type 1 diabetes, graft-versus-host disease, acute myocardial infarction, and cystic fibrosis (Gottlieb et al., 2014; Sorrells et al., 2015; Rachmiel et al., 2016; Brener et al., 2018). Here, SERPINA1 is linked to graft versus host disease.