Abstract
During interferon (IFN) treatment in 22 cases of chronic hepatitis C, fluctuations in the serum level of thrombomodulin (TM) concentration were examined. IFN was administered daily for 2 or 4 weeks, then every other day (3 times a week) for 20 or 22 weeks. The serum level of TM concentration prior to IFN treatment was significantly high in comparison with the healthy controls (p<0.01). It was reduced significantly after 1 and 2 weeks of IFN treatment (p<0.0001, for both). The serum level of TM was increased at the end of IFN treatment as compared to those during daily administration of IFN, and there was no decrease as compared to the pretreatment level. In the group of patients who responded to IFN treatment (group R), the serum level of TM concentration 6 months after treatment rose to the pretreatment level; but one year after the end of treatment, it was down to the level of the healthy control. In the group of patients who did not respond to IFN treatment (group NR), a significant increase was noted (p<0.05) at 6 months after treatment in comparison with the pretreatment level. This was also significantly high (p<0.05) in comparison with the level for group R. The serum level of TM decreased during daily administration of IFN, and it decrease was not associated with pathological changes, but rather was presumed to be due to the action of IFN which works directly on endothelial cells and suppresses TM expression. On the other hand, increased the serum level of TM after the end of IFN treatment was suggested to be attributable to reaction against TM suppression or endothelial injury caused by IFN.
