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A sustained viral response (SVR) after interferon-based therapy of chronic hepatitis C virus (HCV) infection is regarded to represent a cure. Previous studies have used different markers to clarify whether an SVR truly represents a cure, but no study has combined a clinical work-up with highly sensitive HCV RNA detection, and the determination of immune responses.To determine clinical, histological, virological and immunological markers 5-20 years after SVR.In 54 patients, liver biochemistry, histology and elastography were evaluated. Liver biopsies, plasma and peripheral blood mononuclear cells (PBMCs) were tested for minute amounts of HCV RNA. HCV-specific T-cell responses were monitored by ELISpot and pentamer staining, and humoral responses by measuring HCV nonstructural (NS)3-specific antibodies and virus neutralisation.Liver disease regressed significantly in all patients, and 51 were HCV RNA-negative in all tissues tested. There was an inverse association between liver disease, HCV-specific T-cell responses and HCV antibody levels with time from SVR, supporting that the virus had been cleared. The three patients, who all lacked signs of liver disease, had HCV RNA in PBMCs 5-9 years after SVR. All three had HCV-specific T cells and NS3 antibodies, but no cross-neutralising antibodies.Our combined data confirm that a SVR corresponds to a long-term clinical cure. The waning immune responses support the disappearance of the antigenic stimulus. Transient HCV RNA traces may be detected in some patients up to 9 years after SVR, but no marker associates this with an increased risk for liver disease.

In 40 patients with histologically verified chronic hepatitis, (chronic persistent hepatitis, n = 13; chronic active hepatitis without, n = 14; or with cirrhosis, n = 13), of viral and autoimmune origin, serum bile acids (SBA) were measured before and during 3 h after oral ingestion of 1 g chenodeoxycholic acid (CDA). Fasting SBA were elevated in 22 (55%) patients, whereas the CDA loading test was abnormal in 15 (38%) patients and the galactose elimination was prolonged in 16 (40%) patients. In patients with chronic active hepatitis, 20/27 had elevated SBA either in the fasting state (18/27) or after the CDA loading test (13/27). Normal SBA values were found in 9/13 (70%) patients with chronic persistent hepatitis. Thus, fasting SBA is not sensitive enough to detect mild chronic inflammatory liver disease as chronic persistent hepatitis, but seems to be as sensitive as the galactose elimination or CDA loading tests in detecting potential severe liver disease. Fasting SBA may thus be used as a complement of conventional liver tests in the follow-up of chronic hepatitis as assessment of liver function. An oral CDA loading and an i.v. galactose elimination test add no further information to that given by fasting serum bile acids.

Forty patients with chronic hepatitis C virus (HCV) infection were treated with 3 MU interferon alfa-2b given subcutaneously for 60 weeks. A biochemical response with normalization of serum alanine aminotransferase (s-ALT) levels was seen in 24 patients (60%) at treatment cessation. A sustained response with continuously normal s-ALT levels during 24 weeks of follow up was seen in 15 of these 24 patients (62%), all of whom also became HCV RNA negative in serum. Histological changes in the pre- and posttreatment liver biopsies were assessed using a numerical scoring system. Biochemical responders had a significant decrease in all four scored categories: portal inflammation, piecemeal necrosis, spotty necrosis and fibrosis. Non-responders had a significant decrease in piecemeal necrosis and spotty necrosis, whereas the scores for portal inflammation and fibrosis remained unchanged. There was no significant difference in any of the scored categories in the pretreatment biopsy between responders and non-responders. We conclude that patients suffering from chronic HCV infection who responded biochemically and virologically to interferon treatment also improved their liver histology. Necroinflammatory activity decreased to some extent in biochemical non-responders, possibly giving them some benefit from the treatment, but not to the same extent as responders. No specific histological pretreatment findings were predictive of biochemical response to interferon treatment.

The histological outcome in liver biopsies following 9 months of interferon alpha-2b treatment was assessed in detail in 19 patients with chronic posttransfusion non-A, non-B hepatitis (PTH-NANB) and compared with 12 untreated PTH-NANB patients. Fourteen (74%) treated and 7 (58%) control patients were reactive for antibodies against hepatitis C virus (anti-HCV). Liver biopsies taken before and after the 9-month period were scored numerically for portal inflammation, piecemeal necrosis (PMN) and fibrosis, without knowledge of whether the specimens came from control or treated patients. There were no score differences in the initial biopsies between the treated and control group. In the follow-up biopsies the treated group showed significantly less portal inflammation, PMN and fibrosis than the control group (p less than 0.05-0.01). When paired samples from the treated group were compared, significantly regressed portal inflammation, PMN and fibrosis were noted in the follow-up biopsies (p less than 0.05-0.001). The presence or not of anti-HCV antibodies in serum had no impact on the histological response to interferon treatment. We conclude that a 9-month course of interferon alpha-2b treatment significantly diminishes not only inflammation but also fibrosis in the liver of patients with PTH-NANB whether they are anti-HCV reactive or not.

Sera from 62 hepatitis C virus (HCV)-infected Swedish blood donors were tested by a nested polymerase chain reaction using primers targeting the 5'-noncoding region of the GB virus-C/hepatitis G (GBV-C/HGV) genome and an enzyme-linked immunosorbent assay that detects antibodies to the envelope protein E2 of GBV-C/HGV (anti-E2). Fourteen (22%) and 21 (34%) of the 62 blood donors were found to be GBV-C/HGV RNA and anti-E2 positive, respectively. None of the blood donors was positive for both GBV-C/HGV RNA and anti-E2. Thus, 35 of 62 (56%) HCV-infected donors had been exposed to GBV-C/HGV infection. At sequencing of the 14 GBV-C/HGV isolates, 12 were identified as subtype 2a and 2 as subtype 2b. One of 7 (14%) donors with mild liver disease such as steatosis and nonspecific reactive hepatitis had been exposed to GBV-C/HGV vs. 34 of 55 (62%) with chronic hepatitis with or without cirrhosis (P = 0.04). All other differences in histology were small between HCV and dual HCV GBV-C/HGV-infected donors. In conclusion, more than half of HCV-infected Swedish blood donors in this study were positive for either GBV-C/HGV RNA or anti-E2. GBV-C/HGV viremia and seropositivity were mutually exclusive.

A polymerase chain reaction (PCR)-based assay using primers against the hepatitis C core gene has been described [Okamoto et al. (1992a): Journal of General Virology 73:673-679]. Within the two major HCV genotypes 1 and 2, the Okamoto system identifies two subtypes each (1a, 1b and 2a, 2b, respectively). Typing is achieved by a primary PCR with consensus primers followed by a nested PCR with type specific primers. The original assay was modified by addition of a parallel second PCR identifying the recently described major genotype 3. The assay also identifies in duplicate subtype 1b (type II by Okamoto), suggested to respond poorly to interferon. Reaction conditions were reviewed and melting temperatures of all typing primers equalised to increase strigency. The modified system functioned well and typing results were supported by partial core sequencing. The following distribution of genotypes was found in 53 hepatitis C virus (HCV) infected Swedish blood donors: genotype 1a (57%), 3 (19%), 1b (13%), and 2b (11%). In six recipients of HCV infected blood identified in a retrospective study, the recipient HCV genotype was identical to donor HCV genotype. Furthermore, in HCV positive couples identical genotype was observed when only one partner had an external risk factor; whereas genotypes were often diverse if both sex partners had parenteral risk factors. Finally, a cluster of hepatitis C cases in a haemodialysis unit was evaluated retrospectively. Eight patients had genotype 1b, two had mixed 1a and 1b, and one had type 1a. The modified HCV genotyping assay was of value in examining different epidemiological situations and can be expanded presumably to include future genotypes.