PD-L1 expression, tumor mutational burden, and response to immunotherapy in patients with MET exon 14 altered lung cancers.

Background: MET exon 14 alterations are actionable oncogenic drivers. Durable responses to MET inhibitors are observed in patients with advanced MET exon 14-altered lung cancers in prospective trials. In contrast, the activity of immunotherapy, PD-L1 expression and tumor mutational burden (TMB) of these tumors and are not well characterized. Patients and methods: Patients with MET exon 14-altered lung cancers of any stage treated at two academic institutions were identified. A review of clinicopathologic and molecular features, and an analysis of response to single-agent or combination immune checkpoint inhibition were conducted. PD-L1 immunohistochemistry was carried out and TMB was calculated by estimation from targeted next-generation sequencing panels. Results: We identified 147 patients with MET exon 14-altered lung cancers. PD-L1 expression of 0%, 1%-49%, and ≥50% were 37%, 22%, and 41%, respectively, in 111 evaluable tumor samples. The median TMB of MET exon 14-altered lung cancers was lower than that of unselected non-small-cell lung cancers (NSCLCs) in both independently evaluated cohorts: 3.8 versus 5.7 mutations/megabase (P < 0.001, n = 78 versus 1769, cohort A), and 7.3 versus 11.8 mutations/megabase (P < 0.001, n = 62 versus 1100, cohort B). There was no association between PD-L1 expression and TMB (Spearman's rho=0.18, P = 0.069). In response-evaluable patients (n = 24), the objective response rate was 17% (95% CI 6% to 36%) and the median progression-free survival was 1.9 months (95% CI 1.7-2.7). Responses were not enriched in tumors with PD-L1 expression ≥50% nor high TMB. Conclusion: A substantial proportion of MET exon 14-altered lung cancers express PD-L1, but the median TMB is lower compared with unselected NSCLCs. Occasional responses to PD-1 blockade can be achieved, but overall clinical efficacy is modest.

Changes in quality of life and sexual health are associated with low-dose peginterferon therapy and disease progression in patients with chronic hepatitis C.

BACKGROUND: Primary analysis of the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) Trial showed long-term peginterferon therapy did not reduce complications in patients with chronic hepatitis C and advanced fibrosis or cirrhosis. AIM: To assess the effects of long-term peginterferon therapy and disease progression on health-related quality of life (HRQOL), symptoms and sexual health in HALT-C patients. METHODS: A total of 517 HALT-C patients received peginterferon alfa-2a (90 microg/week); 532 received no additional treatment for 3.5 years. Patients were followed up for outcomes of death, hepatocellular carcinoma and hepatic decompensation. Sexual health, SF-36 scores and symptoms were serially assessed by repeated-measures analyses of covariance. RESULTS: Patients with cirrhosis (n = 427) reported lower general well-being and more fatigue (P < 0.001) than patients with fibrosis (n = 622). Physical scores declined significantly over time, independent of treatment, and patients with cirrhosis reported lower scores. Vitality scores were lower in those with cirrhosis, and treated patients experienced a greater decline over time than untreated patients; HRQOL rebounded after treatment ended. Patients with a clinical outcome had significantly greater declines in all SF-36 and symptom scores. Among men, Sexual Health scores were significantly worse in treated patients and in those with a clinical outcome. CONCLUSION: Clinical progression of chronic hepatitis C and maintenance peginterferon therapy led to worsening of symptoms, HRQOL and, in men, sexual health in a large patient cohort followed up over 4 years (NCT00006164).

Hepatic steatosis in chronic hepatitis C: baseline host and viral characteristics and influence on response to therapy with peginterferon alpha-2a plus ribavirin.

Hepatic steatosis is common in hepatitis C virus (HCV)-infected patients and may be associated with the metabolic syndrome. We studied steatosis in patients treated with peginterferonalpha-2a plus ribavirin. Forty-five of 207 patients (22%) had >5% hepatic steatosis at baseline. Significantly more patients with steatosis than without were HCV genotype 3 (51%vs 14%; P < 0.0001) had higher HCV-RNA (P = 0.0045), body weight (P = 0.0176), body mass index (BMI, P = 0.0352) and serum triglycerides (TG) (P = 0.0364), hypertriglyceridaemia (P = 0.0009), elevated blood pressure/history of hypertension (P = 0.0229) and lower cholesterol (P = 0.0009). Significant steatosis predictors were genotype 3 (OR 9.04, 95% CI 3.85-21.21, P < 0.0001), HCV-RNA (OR 2.96, 1.49-5.88, P = 0.0019) and triglycerides (OR 1.06, 1.02-1.11, P = 0.0071). In genotype 3 patients, HCV-RNA was the only significant predictor (OR 11.15, 2.60-47.81, P = 0.0012). In non-genotype 3 patients, hypertriglyceridaemia was the only significant predictor (OR 1.07, 1.02-1.12, P = 0.0041). 134 of 207 patients (65%) achieved an sustained virological response (SVR) with peginterferon alpha-2a plus ribavirin, similar to the overall response rate. In genotype 3 patients with an SVR, steatosis decreased from 48% to 13% (baseline to end-point). No change was seen in the steatosis rate in non-genotype 3 patients with an SVR. This large and comprehensive analysis of a large data base from a multinational trial further adds to the observations that chronic HCV is associated with hepatic steatosis in approximately a fifth of patients. Further, features of the metabolic syndrome are associated with hepatic steatosis in most of these patients. Steatosis is significantly more common in genotype 3 compared with other genotypes, and in these patients, an SVR is associated with steatosis clearance.

Quantitative analysis of HBV cccDNA from clinical specimens: correlation with clinical and virological response during antiviral therapy.

Attempts to investigate changes in various forms of intrahepatic hepatitis B virus (HBV) DNA during antiviral therapy have been hampered by limitations in technologies and scarcity of adequate tissue for analysis. We used a sensitive, specific assay to detect and quantitate covalently closed circular DNA (cccDNA) from total intrahepatic HBV DNA in clinical liver specimens. Total HBV DNA and cccDNA from 21 needle-biopsy specimens were quantified, with levels ranging from 0.1 to 9.8 copies/cell and 0.3 to 491.0 copies/cell, respectively. Then, we performed the same determinations on baseline and week-52 liver needle-biopsy specimens from eight patients enrolled in a clinical trial and evaluated the association between intrahepatic HBV DNA levels and serological and virological endpoints. In most patients, levels of intrahepatic HBV DNA, including cccDNA, decreased over the 52-week study, regardless of therapy or serological outcome. Higher ratios of cccDNA to total HBV DNA were detected at week 52 than at baseline indicating a shift in predominance of nonreplicating virus in posttreatment specimens. In patients who achieved treatment-related or spontaneous hepatitis B e antigen (HBeAg) responses, including those harbouring tyrosine-methionine-aspartate-aspartate-mutant HBV, levels of intrahepatic and serum HBV DNA suppression were greater than those in patients without HBeAg responses. In conclusion, this pilot study of intrahepatic HBV replicative forms in patients with chronic hepatitis B indicated that total intrahepatic and, specifically, cccDNA levels are not static but change as a reflection of serological and virological events.

Decreasing fibrogenesis: an immunohistochemical study of paired liver biopsies following lamivudine therapy for chronic hepatitis B.

BACKGROUND: Activation of hepatic stellate cells is the earliest step in fibrogenesis. Alpha-smooth muscle actin (alpha-SMA), expressed by activated hepatic stellate cells, and C-terminal procollagen alpha1(III) propeptide (PIIICP) are early markers of fibrogenesis and should precede fibrosis. AIM: Determine if suppression of hepatitis B virus replication with lamivudine would decrease fibrogenesis as measured by immunohistochemical markers. METHODS: Paired liver biopsies from patients with hepatitis B before and after therapy with lamivudine (n=47) or placebo (n=33) were studied. alpha-SMA and PIIICP were detected in paraffin-embedded tissue by immunohistochemistry and quantified in a blinded manner by video imaging analysis. RESULTS: Liver biopsies from patients treated with lamivudine showed a significant decrease in alpha-SMA expression (1.06+/-0.23 vs. 0.58+/-0.11, pre vs. post, P<0.05). Placebo recipients had increased levels of alpha-SMA (0.82+/-0.14 vs. 1.32+/-0.21, P<0.05). PIIICP was similarly decreased after lamivudine. Among subjects whose Histologic Activity Index fibrosis score was unchanged or worsened, the mean change in alpha-SMA expression was significantly decreased in the lamivudine group compared with placebo. CONCLUSIONS: Lamivudine decreased markers of hepatic stellate cell activation and collagen synthesis. Immunohistochemical techniques are sensitive for assessing fibrogenesis and will be useful in trials of antiviral and antifibrotic agents.

Predicting response to initial therapy with interferon plus ribavirin in chronic hepatitis C using serum HCV RNA results during therapy.

In patients with chronic hepatitis C, 48 weeks of therapy with interferon (IFN) plus ribavirin results in a sustained virologic response of 40%. Preliminary analysis suggests that measuring HCV RNA at week 24, rather than week 12, might provide the best prediction of treatment response. To assess the clinical utility of serum HCV RNA determinations at different times during therapy as a predictor of a sustained virologic response we evaluated 912 treatment-naïve patients. Patients were randomized to receive IFN-alpha2b, 3 million units (MU) three times weekly (tiw), for 24 or 48 weeks with either ribavirin or placebo, and then followed for 24 weeks. Serum HCV RNA was measured at weeks 4 and 12 in patients treated for 24 weeks; at 4, 12, and 24 weeks during therapy in those treated for 48 weeks, and week 24 post-therapy in all patients. Sustained response was defined as loss of serum HCV RNA at week 24 follow-up. Other patients were considered virologic nonresponders. For patients receiving 48 weeks of combination therapy, detectable serum HCV RNA at week 24 predicted nonresponse (positive predictive value) in 99% of patients compared to 89% at week 12. In patients treated for 24 weeks, testing at week 12 was more predictive of nonresponse than testing at week 4 in the combination-therapy group but not in the monotherapy group. Hence, for combination therapy, testing for serum HCV RNA as a predictor of nonresponse is most accurate at week 24 of therapy; a positive test correctly identified 99% of nonresponders.

Nomenclature for antiviral-resistant human hepatitis B virus mutations in the polymerase region.

There is currently no universally accepted numbering convention for the antiviral drug-related resistance mutations in the reverse transcriptase (rt) domain of the human hepatitis B virus (HBV) polymerase. The published inconsistencies have resulted from different HBV genotypes. A standardized numbering system for HBV polymerase is proposed. The new system is based on functional observations of HBV surface gene proteins (preS1, preS2, and HBsAg) and on the current convention used for human immunodeficiency virus type 1 (HIV-1) polymerase proteins (protease, rt, and integrase), in which the amino acid numbering restarts at the first codon position of each domain. The HBV polymerase protein can be divided into 4 domains (terminal protein, spacer, rt, ribonuclease H) and each of these can be numbered separately. In this proposal, the HBV rt domain starts with the highly conserved EDWGPCDEHG motif, contains 344 amino acids, and the lamivudine-related resistance mutations are found at amino acid rtL180M (previously amino acid 528, 526, 515, or 525) and rtM204V/I (previously 552, 550, 539, or 549). The new consensus rt domain numbering system is genotype independent and allows investigators to number any previously and newly discovered antiviral-related amino acid change in a standardized manner.

A multicenter United States-Canadian trial to assess lamivudine monotherapy before and after liver transplantation for chronic hepatitis B.

Seventy-seven liver transplant candidates were enrolled in a multicenter study in which patients were treated with lamivudine (100 mg daily) without the adjunctive use of hepatitis B immune globulin. Treatment was begun while patients awaited liver transplantation and continued after transplantation. All were hepatitis B surface antigen (HBsAg) positive, and 61% had detectable hepatitis B e antigen (HBeAg) and HBV DNA when treatment was begun. Forty-seven underwent liver transplantation and 30 did not. Median study participation was 38 months (range, 2.7-48.5) in the transplanted patients and 26 months (range, 0.1-37) in the nontransplanted group. Twenty-five of 42 (60%) transplanted patients with 12 or more weeks of posttransplantation follow-up were HBsAg negative at the last study visit. At treatment week 156, 13 of 22 (59%) remained HBsAg negative, and all 9 reinfected patients were HBV-DNA positive before treatment. In the nontransplanted patients, HBeAg was initially detectable in 20 of 27 (74%) but this decreased to 3 of 17 (18%) after 104 weeks of treatment, and significant improvement in biochemical parameters was observed. HBV-DNA polymerase mutants were detected in 15 (21%) and 6 (20%) of the transplanted and nontransplanted patients, respectively. When compared with historical cohorts, lamivudine-treated patients appeared to have improved survival, and transplanted patients had a decrease in the rate of recurrent HBV infection. Lamivudine therapy was partially effective in preventing recurrent HBV infection when given before and after transplantation. Thus, future trials using a combination of HBIg and lamivudine are needed to assess the optimal prophylactic therapy.

The impact of interferon plus ribavirin on response to therapy in black patients with chronic hepatitis C. The International Hepatitis Interventional Therapy Group.

BACKGROUND & AIMS: Black patients with chronic hepatitis C have lower response rates than white patients to interferon monotherapy. The factors responsible for these differences are unknown, as is the impact of combination antiviral therapy on responsiveness among ethnic groups. We evaluated the impact of race on response to therapy in these patients. METHODS: A total of 1744 patients with chronic hepatitis C were randomized in 2 recent clinical trials to receive 24 or 48 weeks of interferon monotherapy or interferon-ribavirin combination therapy. RESULTS: Sustained virologic responses occurred in 27% of 1600 whites, 11% of 53 blacks (P = 0.01 vs. white), 44% of 32 Asians, and 16% of 27 Hispanics. No black patient had a sustained virologic response to interferon monotherapy, but 20% and 23% had sustained responses to 24 and 48 weeks, respectively, of combination therapy. Among black patients, 96% had hepatitis C genotype 1 compared with 65% of white subjects (P < 0.0001). Sustained response rates were similar for black and white patients with genotype 1 infection (23% vs. 22%, respectively). Compared with whites, black patients were older, weighed more, and had higher median Histologic Activity Index scores but did not differ in sex, baseline alanine aminotransferase or hepatitis C virus (HCV)-RNA levels, degree of fibrosis or percentage with cirrhosis, or other demographic variables. White subjects had a significantly greater reduction in HCV-RNA levels than blacks at weeks 4, 12, 24, and 48 of therapy, but only for black patients treated with interferon monotherapy. The decreased reduction of HCV-RNA reduction among blacks was eliminated by combination therapy. CONCLUSIONS: These observations suggest that the impaired responsiveness of black patients to interferon monotherapy can be overcome partially by combination interferon-ribavirin therapy.

Quantitation of hepatitis B viremia and emergence of YMDD variants in patients with chronic hepatitis B treated with lamivudine.

Hepatitis B viremia and emergence of hepatitis B virus (HBV) YMDD variants with reduced susceptibility to lamivudine were analyzed in patient sera from a phase II study of extended lamivudine therapy. Within 12 weeks, all patients exhibited a marked virologic response to lamivudine: >99% reduction (median 5 log decrease) in serum HBV DNA levels. Virus remained at >104 genomes/mL in 11 patients and decreased to <104 genomes/mL in the remaining 12 patients. In 10 patients, detectable YMDD variants emerged during the course of treatment. Six patients, including 3 with YMDD variants, experienced hepatitis B e antigen seroconversion while on lamivudine therapy or soon after its discontinuation. No patients with HBV DNA levels >104 genomes/mL seroconverted. Thus, patients who respond to lamivudine therapy with dramatic reductions in viral DNA level (to <104 genomes/mL) appear more likely to seroconvert than patients who do not achieve this level of HBV clearance.

Lamivudine as initial treatment for chronic hepatitis B in the United States.

BACKGROUND AND METHODS: Although the nucleoside analogue lamivudine has shown promise in patients with chronic hepatitis B, long-term data on patients from the United States are lacking. We randomly assigned previously untreated patients with chronic hepatitis B to receive either 100 mg of oral lamivudine or placebo daily for 52 weeks. We then followed them for an additional 16 weeks to evaluate post-treatment safety and the durability of responses. The primary end point with respect to efficacy was a reduction of at least 2 points in the score on the Histologic Activity Index. On this scale, scores can range from 0 (normal) to 22 (most severe abnormalities). RESULTS: Of the 143 randomized patients, 137 were included in the efficacy analysis: 66 in the lamivudine group and 71 in the placebo group. The other six patients were excluded at the base-line visit because of the absence of a documented history of hepatitis B surface antigen for at least six months. After 52 weeks of treatment, lamivudine recipients were more likely than placebo recipients to have a histologic response (52 percent vs. 23 percent, P<0.001), loss of hepatitis B e antigen (HBeAg) in serum (32 percent vs. 11 percent, P=0.003), sustained suppression of serum hepatitis B virus (HBV) DNA to undetectable levels (44 percent vs. 16 percent, P<0.001), and sustained normalization of serum alanine aminotransferase levels (41 percent vs. 7 percent, P<0.001), and they were less likely to have increased hepatic fibrosis (5 percent vs. 20 percent, P=0.01). Lamivudine recipients were also more likely to undergo HBeAg seroconversion, defined as the loss of HBeAg, undetectable levels of serum HBV DNA, and the appearance of antibodies against HBeAg (17 percent vs. 6 percent, P=0.04). HBeAg responses persisted in most patients for 16 weeks after the discontinuation of treatment. Lamivudine was well tolerated. Self-limited post-treatment elevations in serum alanine aminotransferase were more common in lamivudine recipients: 25 percent had serum alanine aminotransferase levels that were at least three times base-line levels, as compared with 8 percent of placebo recipients (P=0.01). The clinical condition of all patients remained stable during the study. CONCLUSIONS: In U.S. patients with previously untreated chronic hepatitis B, one year of lamivudine therapy had favorable effects on histologic, virologic, and biochemical features of the disease and was well tolerated. HBeAg responses were generally sustained after treatment.

Extended lamivudine retreatment for chronic hepatitis B: maintenance of viral suppression after discontinuation of therapy.

In patients with chronic hepatitis B, brief lamivudine therapy suppresses hepatitis B virus (HBV) DNA but results infrequently in sustained losses of virus replication posttreatment. We evaluated treatment response and its posttreatment durability during up to 18 months of lamivudine therapy (100 mg/d) in 24 patients who had hepatitis B e antigen (HBeAg) despite 1 to 3 months of prior therapy. Therapy was to be stopped after HBeAg loss or seroconversion (acquisition of antibody to HBeAg); posttreatment monitoring continued for 6 months. During therapy, which was well tolerated, HBV DNA became undetectable in all evaluable patients, accompanied by reduced alanine transaminase (ALT) activity. The cumulative 18-month confirmed loss of HBeAg during therapy was 9 of 24 (38%) and seroconversion was 5 of 24 (21%). Therapy was discontinued after HBeAg loss/seroconversion in 7 patients, and HBeAg status was maintained in all. Four of the patients with HBeAg responses lost HBsAg at least once. In 10 (43%) of 23 patients tested, we identified HBV polymerase YMDD mutations, 3 with detectable HBV DNA (2 with ALT elevations) and 7 without virological/biochemical breakthrough. In conclusion, up to 18 months of lamivudine therapy was well tolerated, suppressed HBV replication consistently, and tripled the frequency of HBeAg losses observed during brief-duration therapy; HBeAg loss/seroconversion remained durable posttreatment. The emergence of YMDD-variant HBV was relatively common but occurred typically without reappearance of detectable HBV DNA or ALT elevation. Our observations suggest that lamivudine can be stopped after confirmed HBeAg loss or seroconversion.

Mutations in the NS5A region do not predict interferon-responsiveness in american patients infected with genotype 1b hepatitis C virus.

A striking association has been demonstrated recently between mutations in amino acid residues 2209-2248 of the nonstructural protein 5a (NS5a) region of hepatitis C virus (HCV) and sustained responses to interferon in Japanese patients infected with genotype 1b. Therefore, analysis of this sequence has been suggested as a predictor of treatment response. We sought to determine whether mutations in this region predict outcome in U.S. patients infected with genotype 1b hepatitis C virus (HCV-1b). We analyzed stored pretreatment sera retrospectively from 22 patients with HCV-1b infection who had received interferon alpha-2b (IFNalpha-2b) as part of a controlled trial. Two patients were sustained responders (SR), 7 were transient responders (TR), and 13 were nonresponders (NR). We performed nested reverse transcription-polymerase chain reaction (RT-PCR) on extracted RNA using primers flanking HCV amino acids 2209-2248 and sequenced the PCR products directly. The deduced amino acid sequences were compared with the prototype HCV-J. Isolates with four or more deviations from the prototype were defined as "mutant" type, those with one to three substitutions as "intermediate" type, and those matching the prototype as "wildtype." Of the 22 HCV-1b isolates, 6 were wildtype, 11 intermediate type, and 5 mutant type. Both of the SRs were intermediate type. The 20 TRs and NRs were distributed among mutant (5), intermediate (9), and wildtype (6). Of the five patients with mutant virus, four were NR and one a TR. Variation in NS5a(2209-2248) fails to predict interferon responsiveness in this cohort of American patients infected with HCV-1b. Thus, the utility of this sequence as a predictor of interferon responsiveness appears to be specific to Japanese patients and may reflect differences between patient groups in treatment regimens, host genetic background, or alterations in the interferon signaling pathway induced by surrounding sequences within or outside NS5a. Overall, NS5a is not as integral a determinant of interferon responsiveness as previously suggested.

Hepatitis C virus genotypes and viremia and hepatocellular carcinoma in the United States.

OBJECTIVE: Hepatitis C virus (HCV) is a well recognized cause of hepatocellular carcinoma (HCC). The pathogenic significance of HCV genotypes in hepatocarcinogenesis is undefined. The aim of this study was to investigate the genotypic distribution and viremic level of HCV in patients with HCV-associated cirrhosis with or without HCC. METHODS: A total of 28 HCV-infected patients with HCC (HCC+) and 38 patients with HCV-associated cirrhosis without HCC (HCC-) were studied. HCV genotype was assessed by the genotype-specific polymerase chain reaction (PCR) method of Okamoto and restriction fragment length polymorphism (RFLP) of the 5' untranslated region (5' UTR). Hepatitis C viremia was quantitated with the branched-chain DNA (bDNA) assay. RESULTS: Using the Okamoto method, we found genotype 1b in 64% of the HCC+ group and 74% of the HCC- group, 36% of the HCC+ group and 16% of the HCC- group were coinfected with a combination of genotype 1b and another genotype. Using the RFLP method, we found genotype 1b in 41% of the HCC+ group and in 24% of the HCC- group. Other genotypes accounted for 18% of the HCC+ group and 55% of the HCC- group; no combination genotypes were identified. Poor concordance occurred between the two genotyping methods. Mean bDNA levels were not significantly different between the two groups. CONCLUSIONS: Our study demonstrates that no particular HCV genotypes were associated with HCC and genotype did not appear to influence the development of HCV-associated HCC.

Multicenter study of lamivudine therapy for hepatitis B after liver transplantation. Lamivudine Transplant Group.

Hepatitis B after liver transplantation is often fatal, and no proven medical therapy exists for this condition. We chose to study the potential efficacy of lamivudine therapy for patients with chronic hepatitis B after liver transplantation. Fifty-two patients with chronic hepatitis B after liver transplantation were treated in an open label, multicenter study. Each had detectable hepatitis B virus (HBV) DNA in serum and 45 (87%) had detectable serum hepatitis B e antigen before treatment. Patients were treated for 52 weeks with lamivudine (100 mg daily). The primary endpoint was undetectability of HBV DNA; secondary endpoints included normalization of serum alanine transaminase (ALT) levels, disappearance of hepatitis B e antigen, and improvement in liver histology. After treatment, 60% of patients had undetectable HBV DNA by solution hybridization assay, 14 (31%) of the initially positive patients lost hepatitis B e antigen; hepatitis B surface antigen was undetectable in 3 (6%); and serum ALT levels normalized in 71%. Blinded histological assessments showed improvement in the histological activity index (P =.007 for periportal necrosis,.001 for lobular necrosis, and.013 for portal inflammation). YMDD variants of HBV, potentially associated with drug resistance, were detected in 14 (27%) of the patients. Repeat liver biopsies in 7 patients with the mutated virus were unchanged in 2, improved in 2, and worse in 3. We conclude that lamivudine is a potentially effective therapy for hepatitis B after liver transplantation.

Hepatitis C virus-associated fibrosing cholestatic hepatitis after renal transplantation: response to interferon-alpha therapy.

Fibrosing cholestatic hepatitis (FCH) has recently been described after solid organ transplantation in patients with hepatitis C virus (HCV) infection. Typically, FCH is characterized by an ominous clinical course leading to progressive hepatic failure and death if liver transplantation is not performed. Two HCV-infected patients underwent cadaveric renal transplantation for end-stage renal disease resulting from membranous nephropathy and diabetic nephropathy. The time intervals between transplantation and the biopsy diagnosis of FCH for the two patients were 7 months and 10 years. Both patients presented with jaundice, hyperbilirubinemia, and mild-to-moderate elevations in serum aspartate aminotransferase. One patient was also found to have type II mixed cryoglobulinemia. Interferon-alpha therapy was begun after a diagnosis of FCH was established by liver biopsy. Liver test abnormalities normalized rapidly. When cholestatic hepatic deterioration develops in an HCV-infected organ allograft recipient, the diagnosis of FCH should be considered and a liver biopsy performed. Our observations indicate that FCH can respond to antiviral therapy.

Liver-derived CTL in hepatitis C virus infection: breadth and specificity of responses in a cohort of persons with chronic infection.

Hepatitis C virus (HCV)-specific CTL have been found within the inflammatory infiltrate of the liver of chronically infected individuals, but the breadth and specificity of the CTL response in relation to viral load are less well characterized. In this study, we analyzed the intrahepatic CTL response in liver biopsy specimens from 44 chronically infected subjects. Liver-infiltrating lymphocytes were expanded polyclonally in bulk cultures, and multiple clones were derived by limiting dilution. HCV-specific CTL responses directed at genotype 1a structural proteins were assessed in all subjects, and 22 subjects were tested more comprehensively using vectors expressing all structural and nonstructural HCV Ags. CTL responses were further characterized to determine the HLA restriction and optimal epitopes recognized. In those persons screened for recognition of all HCV Ags, HLA class I-restricted CTL were detected in 45%. Nineteen different CTL epitopes were identified, which were distributed throughout the genome; only one epitope was targeted by more than one person. In those persons with CTL responses, the breadth of response ranged from one to five epitopes. There was no correlation between the presence of a detectable CTL response and viral load. These results indicate considerable heterogeneity in detectable HCV-specific CTL responses in chronically infected persons. The mechanisms by which HCV persists during chronic infection remain to be clarified.