A2M and allergic rhinitis: Of these, complement C4-B (C4B), alpha-1-acid glycoprotein 2 (ORM2) and phospholipid transfer protein (PLTP) were exclusively present in allergic rhinitis; while alpha-2-macroglobulin (A2M), apolipoprotein A-II (APOA2), vitamin D-binding protein (GC), complement C3 (C3), apolipoprotein A-I (APOA1), BPI fold-containing family B member 2 (BPIFB2), and clusterin (CLU) were also found in healthy controls.