Immunogen sequence: SSPGKPPRLV GGPMDASVEE EGVRRALDFA VGEYNKASND MYHSRALQVV RARKQIVAGV NYFLDVELGR TTCTKTQPNL DNCPFHDQPH LKRKAFCSFQ IYAVPWQGTM TLSKSTCQDA; Positive Samples: U-251MG, SKOV3, A-549, Mouse brain. Cystatin C, a member of the type 2 cystatin sup