For the measurement of the levels of individual complement components in the context of therapeutic intervention, the measurement of C1-INH levels has the clearest and longest-standing utilization, specifically in the context of hereditary angioedema and C1-INH replacement therapies so it is unsurprising that this area is currently part of specific efforts to improve and standardize (59, 60). Here, SERPING1 is linked to hereditary angioedema.