Cleavage of cystatin C is not associated with multiple sclerosis.
Recently, Irani and colleagues proposed a C-terminal cleaved isoform cystatin C (12.5 kDa) in cerebrospinal fluid as a marker of multiple sclerosis. In this study, we demonstrate that the 12.5 kDa product of cystatin C is formed by degradation of the first eight N-terminal residues. Moreover, such a degradation is not specific in the cerebrospinal fluid of multiple sclerosis, but rather is given by an inappropriate sample storage at -20 degrees C. We conclude that the use of the 12.5 kDa product of cystatin C in cerebrospinal fluid might lead to a fallacious diagnosis of multiple sclerosis. Preanalytical validation procedure is mandatory for proteomics investigations.
Del Boccio
Piero
P
Centro Studi sull'Invecchiamento, Fondazione G. D'Annunzio, Chieti, Italy.
Pieragostino
Damiana
D
Lugaresi
Alessandra
A
Di Ioia
Maria
M
Pavone
Barbara
B
Travaglini
Daniela
D
D'Aguanno
Simona
S
Bernardini
Sergio
S
Sacchetta
Paolo
P
Federici
Giorgio
G
Di Ilio
Carmine
C
Gambi
Domenico
D
Urbani
Andrea
A
D016477:Artifacts; D055316:Cystatin C; D015891:Cystatins / Q000134:cerebrospinal fluid* / Q000737:chemistry*; D004356:Drug Storage; D005615:Freezing; D006801:Humans; D008970:Molecular Weight; D009103:Multiple Sclerosis / Q000134:cerebrospinal fluid*; D010446:Peptide Fragments / Q000134:cerebrospinal fluid / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D010446:Peptide Fragments