Hepatitis B virus RNA is measurable in serum and can be a new marker for monitoring lamivudine therapy.
BACKGROUND
Changes in the serum hepatitis B virus (HBV) RNA level during lamivudine therapy were compared to those in the serum HBV DNA and HBV core-related antigen (HBVcrAg) levels in 24 patients with chronic hepatitis B.


METHODS
For measurement of HBV RNA, total nucleic acid was extracted from serum samples and treated with RNase-free DNase I. After cDNA synthesis from extracted RNA, HBV RNA was measured by real-time detection polymerase chain reaction.


RESULTS
The peak fraction of HBV RNA in serum samples was consistent with peak fractions of HBV DNA and HBV core protein in a sucrose gradient analysis, indicating that HBV RNA was incorporated into virus particles. All levels of HBV DNA, HBV RNA, and HBVcrAg decreased gradually during lamivudine therapy (P < 0.001 for all). The amount of decrease from the start of lamivudine therapy was significantly higher for HBV DNA than for HBV RNA or HBVcrAg during 6 months of lamivudine therapy (P < 0.001 for all). However, a similar difference was not seen between HBV RNA and HBVcrAg levels during that period. The HBV RNA level was significantly correlated (P < 0.001 for all) with levels of HBV DNA and HBVcrAg both at the beginning and 2 months after the start of lamivudine therapy.


CONCLUSIONS
HBV RNA is detectable in serum in a form indicating incorporation into virus particles, and its serum level might serve as a new viral marker with a significance different from that of HBV DNA in lamivudine therapy.
Rokuhara
Akinori
A
Department of Medicine, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
Matsumoto
Akihiro
A
Tanaka
Eiji
E
Umemura
Takeji
T
Yoshizawa
Kaname
K
Kimura
Tatsuji
T
Maki
Noboru
N
Kiyosawa
Kendo
K
D000328:Adult; D000368:Aged; D002499:Centrifugation, Density Gradient; D004279:DNA, Viral / Q000097:blood; D005260:Female; D006512:Hepatitis B Core Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000302:isolation & purification*; D019694:Hepatitis B, Chronic / Q000097:blood* / Q000188:drug therapy*; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood*; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*; D019562:Viral Load
D004279:DNA, Viral; D006512:Hepatitis B Core Antigens; D012367:RNA, Viral; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine