AIM:Transforming growth factor (TGF)-β_1,metalloproteinase(MMP)-1 and its tissue inhibitor (TIMP)-1 are consideredpredictive biomarkers of chronic hepatitis activity and fibrosis.The aim of this study was to evaluate the effect of lamivudinetreatment on the plasma levels of these peptides in patientswith chronic hepatitis B.METHODS:TGF-β_1,MMP-1 and TIMP-1 plasma concentrationswere measured with an enzyme immunoassay in 40 patientstreated with lamivudine for 48 wk.Elimination of HBV-DNAand HBV antigens was evaluated 24 wk after treatmentcompletion.RESULTS:Baseline TGF-β (29.6±2.2 ng/mL) and TIMP-1(1 578±93 ng/mL) significantly exceeded normal values(18.3±1.6 ng/mL and 1 102±67 ng/mL respectively).Lamivudinetreatment resulted in a significant decrease of TGF-β_1 andTIMP-1 during treatment with an increase after 24 wk oftreatment.Pretreatment MMP-1 levels (6.7±0.7 ng/mL) weresignificantly lower than normal values (11.9±0.9 ng/mL) andincreased during treatment and follow-up.A significantcorrelation was noted between TGF-β_1 or TIMP-1 andaminotransferases as well as fibrosis scored in liver biopsyspecimens.There were no statistically significant differencesof TGF-β_1,TIMP-1 and MMP-1 between four groups atbaseline,24 and 48 wk of treatment.TGF-β_1 and TIMP-1levels increased significantly in non-responders and normalizedin responders at wk 72.MMP-1 also normalized in respondersand decreased to values significantly lower than normal innon-responders.CONCLUSION:These findings support the role of TGF-β_1,TIMP-1 and MMP-1 in the pathogenesis of chronic hepatitis B.Because of their association with hepatic injury and antiviraltreatment efficacy,determination of these peptides may beuseful in disease management. AIM: Transforming growth factor (TGF) -β_1, metalloproteinase (MMP) -1 and its tissue inhibitor (TIMP) -1 are considered predictive biomarkers of chronic hepatitis activity and fibrosis. The aim of this study was to evaluate the effect of lamivudinetreatment on the Plasma levels of these peptides in patients with chronic hepatitis B. METHODS: TGF-β_1, MMP-1 and TIMP-1 plasma concentrations were measured with an enzyme immunoassay in 40 patient with or without lamivudine for 48 weeks. Elimination of HBV-DNA and HBV antigens was 24 wk after treatment complex.RESULTS: Baseline TGF-β (29.6 ± 2.2 ng / mL) and TIMP-1 (1 578 ± 93 ng / mL) were significantly exceeded normal values ​​(18.3 ± 1.6 ng / mL and 1 102 ± 67 ng / mL, respectively) respectively) .Lamivudine treatment resulted in a significant decrease of TGF-β_1 and TIMMP-1 during treatment with an increase after 24 wk of treatment. Pleating MMP-1 levels (6.7 ± 0.7 ng / mL) weresignificantly lower than normal values ​​(11.9 ± 0.9 ng / mL) and increased during treatment and follow-up. A si gnificantcorrelation was noted between TGF-β_1 or TIMP-1 andaminotransferases as well as fibrosis scored in liver biopsyspecimens. There were no statistically significant differencesof TGF-β_1, TIMP-1 and MMP-1between four groups atbaseline, 24 and 48 wk of treatment. TGF-β_1 and TIMP-1levels increased significantly in non-responders and normalized in responders at wk 72. MMP-1 also normalized in responders and decreased to values ​​significantly lower than normal innon-responders. CONCLUSION: These findings support the role of TGF-β_1, TIMP-1 and MMP-1 in the pathogenesis of chronic hepatitis B. Because of their association with hepatic injury and antiviraltreatment efficacy, determination of these peptides may be bessembly in disease management.