The effect of interferon alpha and prednisolone on the serum concentrations of the aminoterminal domain of procollagen type III(PIIIP) and type IV (7-S collagen) in patients with chronic hepatitis B.

Since interferons are reported to inhibit collagen synthesis in vivo and in vitro, they are possible anti-fibrogenic drugs. However, little is known about the effect of interferons on connective tissue metabolism in liver disease. To investigate the effect, serum concentrations of the aminoterminal domain of procollagen type III and type IV (7-S collagen) were measured in 16 patients with chronic hepatitis B during alpha interferon treatment. The levels were also determined during prednisolone withdrawal treatment to investigate the effect on hepatic collagen turnover. In patients with chronic hepatitis B, the serum levels of both markers were significantly elevated before any treatment (procollagen type III: 1.10 +/- 0.39 U/ml, 7-S collagen: 6.69 +/- 3.71 ng/ml) compared with levels in 41 healthy volunteers (pro-collagen type III: 0.53 +/- 0.13 U/ml, P < 0.001; 7-S collagen: 4.72 +/- 0.57 ng/ml, P < 0.001). Both levels were even more elevated during interferon therapy (procollagen type III: 1.36 +/- 0.58 U/ml, P < 0.05; 7-S collagen: 8.77 +/- 4.68 ng/ml, P < 0.01). On the other hand, serum procollagen type III and 7-S collagen levels were both decreased during prednisolone treatment (procollagen type III: 0.62 +/- 0.13 U/ml, P < 0.001; 7-S collagen: 4.66 +/- 1.69 ng/ml, P < 0.01). These preliminary data suggest that interferon alpha enhanced, but prednisolone inhibited the turnover of procollagen type III and IV in the liver. Further study is required to interpret this observation in relation to anti-fibrotic therapy.