Consequently, our HKa ELISA may be a useful in vitro assay for helping to predict in vivo efficacy for PKa inhibitors in development for HAE-C1INH and other indications potentially mediated by PKa, such as bradykinin-mediated angioedema (39), diabetic macular edema (40), Alzheimer's disease (15), ischemic stroke (41), myocardial infarction (42), systemic lupus erythematosus (43), cancer (44), and sepsis (45). This evidence concerns the gene SERPING1 and diabetic macular edema.