Quantitative analysis of p40/p46 and p69/p71 forms of 2',5'-oligoadenylate synthetase mRNA by competitive PCR and its clinical application.
BACKGROUND
2',5'-Oligoadenylate synthetases (2-5AS) are type I interferon (IFN)-induced proteins with antiviral capacity. Three major forms of 2-5AS with distinct enzymatic activities have been described in IFN-treated human cells. We measured distinct forms of 2-5AS mRNA to analyze the relationship with its enzymatic activity and response to IFN therapy in chronic hepatitis C.


METHODS
We established a method to quantify p40/p46 and p69/p71 forms of 2-5AS mRNA by use of reverse transcription followed by competitive PCR. The 2-5AS mRNA concentrations were measured in peripheral blood mononuclear cells from 40 patients with chronic hepatitis C and 28 control individuals.


RESULTS
Reconstitution experiments and comparison with Northern blot analyses revealed that our method accurately and linearly quantified 2-5AS mRNA. 2-5AS mRNA concentrations and 2-5AS enzymatic activity were correlated (P <0.03). Our data demonstrated a correlation in 2-5AS mRNA between p40/p46 and p69/p71 (P <0.02), indicating a similar regulation of the expression of these genes. Our data also demonstrated that pretreatment concentrations of 2-5AS mRNA correlated with responses to IFN therapy in chronic hepatitis C.


CONCLUSIONS
Our method for measuring 2-5AS mRNA concentrations could provide an important marker for selecting patients for IFN therapy and may be useful for the development of more effective therapeutic strategies for chronic hepatitis C.
Takahashi
Akira
A
Departments of Medicine and Medical Science, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Iwasaki
Yoshiaki
Y
Miyaike
Jiro
J
Taniguchi
Hideaki
H
Shimomura
Hiroyuki
H
Hanafusa
Tadashi
T
Yumoto
Yasuhiro
Y
Moriya
Akio
A
Koide
Norio
N
Tsuji
Takao
T
D015088:2',5'-Oligoadenylate Synthetase / Q000235:genetics*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000998:Antiviral Agents / Q000627:therapeutic use*; D015152:Blotting, Northern; D005260:Female; D005838:Genotype; D019698:Hepatitis C, Chronic / Q000097:blood / Q000188:drug therapy*; D006801:Humans; D016899:Interferon-beta / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis*; D012044:Regression Analysis; D014407:Tumor Cells, Cultured
D000998:Antiviral Agents; D012333:RNA, Messenger; D016899:Interferon-beta; D015088:2',5'-Oligoadenylate Synthetase