A2M and hereditary angioedema: To test this, additional plasma samples (from different HAE-C1INH patients from the same clinical study with lanadelumab and different healthy controls) were analyzed using commercially available ELISA kits (RayBiotech, Peachtree Corners, GA) for interleukin-21, A2M, and apolipoprotein B. We observed no differences between healthy controls and HAE-C1INH plasma for these 3 proteins (data not shown).