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Sequence heterogeneity of hepatitis C virus (HCV) is unevenly distributed along the genome, and maximal variation is confined to a short sequence of the HCV second envelope glycoprotein (E2), designated hypervariable region 1 (HVR1), whose biological function is still undefined. We prospectively studied serological responses to synthetic oligopeptides derived from HVR1 sequences of patients with acute and chronic HCV infection obtained at baseline and after a defined follow-up period. Extensive serological cross-reactivity for unrelated HVR1 peptides was observed in the majority of the patients. Antibody response was restricted to the IgG1 isotype and was focused on the carboxyterminal end of the HVR1 region. Cross-reactive antibodies could be readily elicited following immunization of mice with multiple antigenic peptides carrying HVR1 sequences derived from our patients. The vigor and heterogeneity of cross-reactive antibody responses were significantly higher in patients with chronic hepatitis compared with those with acute hepatitis and in patients infected with HCV type 2 compared with patients infected with other viral genotypes (predominantly type 1), which suggest that higher time-related HVR1 sequence diversification previously described for type 2 may result from immune selection. The finding of a statistically significant correlation between HVR1 sequence variation, and intensity, and crossreactivity of humoral immune responses provided stronger evidence in support of the contention that HCV variant selection is driven by the host's immune pressure. (HEPATOL-OGY 1999;30:537-545.)Hepatitis C virus (HCV) causes chronic infection in more than 60% of exposed individuals through pathogenetic mechanisms that are still poorly understood. 1 Similarly to human immunodeficiency virus (HIV), HCV is able to persist for a virtually indefinite period of time in the host, despite the coexistence of virus-specific immune responses. 2 How HCV induces chronic infection in the face of detectable cellular and humoral immune responses is currently unknown, but the ability of the virus to undergo rapid and substantial sequence modifications is thought to be a major factor in this process. [2][3][4][5][6][7][8][9][10][11] Sequence variation is unevenly distributed along the HCV genome with maximal nucleotide and aminoacid replacements being localized in a stretch of 31 residues at the N-terminus of the second envelope glycoprotein (E2) region named hypervariable region 1 (HVR1). 12 Sequential studies of sequence changes in acute and chronic HCV infection have shown that viral variants are continuously being selected in this region 13,14 and, therefore, HVR1 variation may be a mechanism by which HCV evades neutralizing responses, leading to persistent infection.Most studies point to HVR1 as the major immunogenic domain of E2, although the presence of additional B-cell sites outside HVR1 has been documented, 15 and a conserved B-cell epitope, only partially overlapping with HVR1, has been recently described that competes for ...

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Propranolol has been reported to prevent the risk of hemorrhage in patients who survived episodes of variceal rupture. Since the first bleeding episode can be lethal, we did a prospective, randomized trial to see whether beta-blockers could also prevent the first hemorrhage. Seventy-nine consecutive cirrhotics with large esophageal varices by endoscopy and who had never bled were randomly allocated to one of the following treatments: placebo; ranitidine (300 mg per day), or nadolol (40 to 120 mg per day)--which is not cardio-selective, reduces portal hypertension and does not interfere with renal flow. Since no significant differences between ranitidine and placebo treatment were observed, the two groups were combined as the control group and compared with the nadolol group. After a mean follow-up of 24 months, only 1 of the 30 patients in the nadolol group had bled, while 11 of the 49 patients in the control group had bled. The percentages of patients who had not bled 1 and 2 years after the inclusion were 100 and 94.4% for the nadolol group and 81.2 and 70.2% for the control group (p less than 0.02), respectively. There were no differences in the mortality rate. In conclusion, nadolol significantly protects against the first gastrointestinal bleeding episode in cirrhotics.

Maintenance of adequate immunosuppression and avoidance of side-effects are the goals of long-term management of all organ-transplanted patients. We here report the final results of a prospective, randomized trial comparing early cyclosporine monotherapy versus double-drug therapy (cyclosporine and steroids) in adult liver transplantation patients. One hundred four patients were randomized 3 months after transplantation either to continue (Group I ‫؍‬ 50 patients) or to stop steroids (Group II ‫؍‬ 54 patients). Patients on a double-drug regimen were maintained long term on methylprednisolone at a dose of 0.1 mg/kg/d. Target cyclosporine trough levels were between 150 and 250 ng/mL in both groups. Our main points of interest were the prevalence of acute and chronic rejections and steroidrelated side-effects in the two groups of patients. Mean follow-up was 41 ؎ 16 months (range, 4-68 months). Patient actuarial survival 2 and 5 years after randomization was similar in the two groups (82% vs. 83% and 82% vs. 77%). The prevalence of acute rejections after randomization was, respectively, 8% and 4%. A single episode of chronic rejection was observed only in a patient on longterm steroid therapy. Side-effects of steroid therapy were less frequent in patients weaned off steroids, and when considering hypertension and diabetes, the differences between the two groups were statistically significant. Early cyclosporine monotherapy is a safe undertaking in liver transplantation because it allows a significant reduction of steroid-related side-effects without increasing the risk of acute and chronic rejection. After 5 years, patient survival was similar in patients with or without steroids. (HEPATOL-OGY 1998;27:1524-1529.)

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Hepatitis C virus (HCV) infection is a dynamic process during which molecular variants are continously selected as the result of virus adaptation to the host. Understanding the nature of HCV genetic variation is central to current theories of pathogenesis and immune response. We prospectively studied hypervariable region 1 (HVR1) variation in the E2 gene of 36 hepatitis C patients, including 10 asymptomatic carriers, followed up for 1 to 2 years. Sequence changes in single and consecutive serum samples were assessed and correlated with clinical and virological parameters of liver disease. A region of the E1 gene was sequenced for comparison in 3 subjects. HVR1 heterogeneity at single time points widely varied in individual patients, did not increase cumulatively over the follow-up period, and did not correlate with HVR1 evolutionary rates. Conversely, the process of HVR1 sequence diversification, although differed considerably among patients, was stable over time and directly correlated with infections by HCV type 2, lower alanine aminotransferase (ALT) levels, and absence of cirrhosis. HCV carriers showed the highest HVR1 variation rates. Our findings indicate that HVR1 variation has an adaptive significance and is associated with favorable features of liver disease and suggest that prospective, rather than static, observations are required to model the process of HCV variation. (HEPATOLOGY 1998;27:1678-1686.)Hepatitis C virus (HCV) shares with other eukaryotic RNA viruses considerable sequence diversity both among isolates from unrelated individuals and within the same individual, 1 in which the virus is not present as a single molecular species, but as a variable population of closely related genomes, 2 according to the model of the viral quasispecies. 3,4 HCV sequence diversity observed among isolates is relevant to the process of viral evolution as it occurred during the history of human populations 1 ; therefore, it has been largely exploited to classify viral variants showing different epidemiologic and pathogenetic features. 5 Conversely, genetic diversity within individuals is more pertinent to the long-term adaptation of the virus to the host and reflects the dynamics of viral populations and the selective mechanisms operating during the course of the infection. 4 Sequence diversity is unevenly distributed throughout the viral genome being highly concentrated at the N-terminus of the E2 envelope glycoprotein, in which an hypervariable region (HVR1) of 31 aminoacids has been identified. 6 This suggests that sequence changes within HVR1 do not simply reflect the intrinsic mutation rates of the virus, but rather indicates that viral variants are actively selected and that genetic variation in this region may have an adaptive significance. [7][8][9][10] The quasispecies nature of the RNA virus populations represents a formidable obstacle to the study of genetic variation; this is a problem further compounded by the lack of structural constraints within protein domains, such as the hypervariable regions of ...