Similar increased serum dipeptidyl peptidase IV activity in chronic hepatitis C and other viral infections.
BACKGROUND
Dipeptidyl peptidase IV is a transmembrane enzyme widely expressed in many cell types, but also present as a soluble form in biological fluids. Its abnormal activity is sometimes associated with liver disease related pathologies.


OBJECTIVE
The aim of this study was to evaluate the clinical relevance of changes in serum DPPIV activity in hepatitis C and other viral infections.


METHODS
DPPIV activity was assessed by using a microplate-based colorimetric assay on serum from 88 subjects: 12 healthy uninfected controls, 10 patients with primary biliary cirrhosis (PBC) as a reference group, 36 HCV-infected patients, and patients suffering from viral infections of different etiologies. Levels of DPPIV activity were compared with: (1) those of other serum biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma glutamyl transpeptidase (GGT), and bilirubin concentrations; and (2) criteria representative of liver histological status.


RESULTS
Compared with healthy subjects, DPPIV activity was significantly increased during viral infections and in PBC (P<0.01). In HCV-infected patients, the median activity (interquartile range, IQR), 29.78 IU/l (24.66-35.95), differed significantly (P<0.05) from that of controls: 21.42 (19.76-24.93). No correlation was observed between DPPIV activity and either ALT, AST, bilirubin, or the stage of liver fibrosis and necroinflammatory activity, although GGT was moderately correlated (r=0.58, P<0.05).


CONCLUSIONS
Although we confirmed an elevation of serum DPPIV activity in PBC, it seems to be a non-specific phenomenon common to viral infections. The absence of correlation between serum DPPIV and markers of liver disease in HCV-infected patients, suggests that this activity originates not only from the liver, but also from other sources such as peripheral blood cells involved in the control of viral infections.
Laboratoire de Virologie, CERVI, UPRES EA 2387, Groupe Hospitalier Pitié-Salpêtrière, 75651 Paris Cedex 13, France.
T
T
Andrieu
V
V
Thibault
I
I
Malet
J
J
Laporte
B
B
Bauvois
H
H
Agut
A
A
Cahour
D000328:Adult; D002779:Cholestasis / Q000201:enzymology / Q000503:physiopathology; D018819:Dipeptidyl Peptidase 4 / Q000097:blood*; D018450:Disease Progression; D005260:Female; D019698:Hepatitis C, Chronic / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology / Q000821:virology; D006801:Humans; D008099:Liver / Q000473:pathology / Q000821:virology; D008105:Liver Cirrhosis, Biliary / Q000201:enzymology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D014777:Virus Diseases / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology / Q000821:virology
D018819:Dipeptidyl Peptidase 4