Immunogen sequence: CYNCPNPTAD CKTAVNCSSD FDACLITKAG LQVYNKCWKF EHCNFNDVTT RLRENELTYY CCKKDLCNFN EQLENGG. CD59 (Protectin) is a small (18-20 kDa) GPI-anchored ubiquitously expressed inhibitor of the membrane attack complex (MAC). CD59 is the key regulato