Effect Of Interferon Alfa Research Articles

P.1.e.012 Effect of interferon-alfa on cortical glutamate in patients with hepatitis C: a proton magnetic resonance spectroscopy study

P.1.e.012 Effect of interferon-alfa on cortical glutamate in patients with hepatitis C: a proton magnetic resonance spectroscopy study

Characteristics of hepatitis C treatment with pegylated interferons and ribavirin

The effect of interferon alfa against hepatitis C virus has been well documented. However, clinical efficacy is low due to the short interferon residence in the body. To prolong half-life, interferon molecules have been bound to the biologically inert polymer, polyethyleneglycol. Pegylated interferons exhibit a longer residence time with an improved clinical efficacy, although the rate of therapeutic failure is still important. Addition of ribavirin to interferon, either pegylated or not, significantly increases efficacy. Therefore, the combination of a pegylated interferon with ribavirin has become the standard treatment of chronic hepatitis C. As the efficacy and safety of such combinations are not yet optimal, different drugs, including other types of long-acting interferon’s and ribavirin analogs, are presently been investigated.

Viral kinetics in hepatitis C or hepatitis C/human immunodeficiency virus-infected patients

Kinetic modeling of hepatitis C virus (HCV) response to interferon (IFN)-based therapy provides insights into factors associated with treatment outcomes. HCV/human immunodeficiency virus (HIV)-co-infected patients show lower response rates vs. HCV-monoinfected patients. Reasons for this remain unclear. This study evaluated kinetic parameters and treatment responses in co-infected vs monoinfected patients. Co-infected patients were randomized within a US multicenter trial (ACTG 5071) to receive pegylated-interferon (PEG-IFN) alfa-2a + ribavirin vs. IFN alfa-2a + ribavirin. Monoinfected controls were matched prospectively for treatment, genotype, age, sex, race, and histology. Quantitative HCV-RNA testing was performed at hours 0, 6, 12, 24, 48, and 72; days 7, 10, 14, 28, and 56; and weeks 12, 24, 48, and 72. Twelve HCV/HIV-co-infected and 15 HCV-monoinfected patients underwent viral kinetic sampling. Among HIV-positive patients the mean CD4(+) count was 325 cells/mm(3). Seventy-five percent of patients were genotype 1. The HCV-RNA level was undetectable at 72 weeks in 25% and 40% of co-infected and monoinfected patients, respectively. Phase 1/2 declines, free virus clearance rate, and infected hepatocyte death rate were not affected by co-infection status but differed by treatment. Efficiency (epsilon) > or = 90% at 60 hours was associated with viral clearance ( P = .02). Modeling with pooled parameters suggests baseline viral load is a key factor in time to response in this cohort. Predicted clearance time increased by 28% in co-infected patients. Co-infection status did not affect key kinetic parameters. Among kinetic parameters, efficiency was associated significantly with viral clearance. Co-infected patients may require longer treatment duration than monoinfected patients given their generally higher baseline viral loads.

Management of side effects of interferon alfa and ribavirin-based treatment of chronic hepatitis C

Management of side effects of interferon alfa and ribavirin-based treatment of chronic hepatitis C

The immune responsiveness in hepatitis C virus infected patients: effects of interferon-alfa/ribavirin combined treatment on the lymphocyte response with special reference to B cells.

Previous data demonstrated that an elevated percentage of hepatitis C virus (HCV) infected patients are endotoxemic. Endotoxemic patients are poor responders to the interferon (IFN)- alpha/ribavirin (RIB) treatment and exhibit lower serum levels of IFN-gamma and interleukin (IL)-10 than the responder counterpart. Here we provide evidence that in endotoxemic HCV+ patients absolute numbers of CD19(+) cells (B cells) are higher than those observed in the non-endotoxemic counterpart at the end of the combined treatment. Moreover, anti lactoferrin (LF) antibodies are more elevated in non-responder HCV+ patients than in the responders. In turn, these autoantibodies may affect the antiviral activity of LF, on the one hand, and, on the other hand abrogate the LF binding to lipopolysaccharides (LPS). Such an interaction hampers the binding of LPS to LPS binding protein, thus inhibiting LPS fixation to CD14(+) cells and, ultimately, leading to a decreased release of proinflammatory cytokines.

Alcohol potentiates hepatitis C virus replicon expression

Alcohol consumption accelerates liver damage and diminishes the anti-hepatitis C virus (HCV) effect of interferon alfa (IFN-α) in patients with HCV infection. It is unknown, however, whether alcohol enhances HCV replication and promotes HCV disease progression. The availability of the HCV replicon containing hepatic cells has provided a unique opportunity to investigate the interaction between alcohol and HCV replicon expression. We determined whether alcohol enhances HCV RNA expression in the replicon containing hepatic cells. Alcohol, in a concentration-dependent fashion, significantly increased HCV replicon expression. Alcohol also compromised the anti-HCV effect of IFN-α. Investigation of the mechanism(s) responsible for the alcohol action on HCV replicon indicated that alcohol activated nuclear factor κB (NF-κB) promoter. Caffeic acid phenethyl ester (CAPE), a specific inhibitor of the activation of NF-κB, abolished alcohol-induced HCV RNA expression. In addition, naltrexone, an opiate receptor antagonist, abrogated the enhancing effect of alcohol on HCV replicon expression. In conclusion, alcohol, probably through the activation of NF-κB and the endogenous opioid system, enhances HCV replicon expression and compromises the anti-HCV effect of IFN-α. Thus, alcohol may play an important role in vivo as a cofactor in HCV disease progression and compromise IFN-α-based therapy against HCV infection. (H epatology 2003;38:57-65.)

Porphyria cutanea tarda as a Predictor of Poor Response to Interferon Alfa Therapy in Chronic Hepatitis C

Background: Porphyria cutanea tarda (PCT) is sometimes associated with hepatitis C virus chronic infection. The aim of this study was to describe the effect of interferon alfa (IFN-a) in the treatment of patients with chronic hepatitis C and PCT. Methods: We treated a total of 66 patients with chronic hepatitis C with IFN-a 2b (5 MU t.i.w.) for 12 months. Twenty-two of these patients suffered from PCT as well. These patients differed from patients without PCT in that they were men, past history of alcohol abuse and HFE gene mutations were more common and the source of infection was almost always unknown. Results: Sustained virologie response was obtained in 19.7% of the 66 treated patients, 27.3% in the non-PCT group and 4.5% in the PCT group (P < 0.05). This difference could not be ascribed to the difference in sex of patients, history of alcohol abuse, HCV genotype or iron status. Conclusion: Multivariate logistic regression analysis revealed that PCT is independently and significantly associated with non-sustained response to IFNa therapy. In conclusion, patients with chronic hepatitis C and PCT rarely responded to IFNa treatment.

Interferon alfa therapy for malignant melanoma: a systematic review of randomized controlled trials.

No standard systemic adjuvant therapy has been proven to increase overall survival in melanoma patients. The effect of interferon alfa (IFNalpha) as a single agent or in combination has been widely explored in clinical trials. The purpose of this study was to assess the benefit of IFNalpha therapy in malignant melanoma. We performed a systematic review of randomized controlled trials comparing regimens with or without IFNalpha adjuvant therapy in melanoma patients. We assessed the effect of IFNalpha therapy on overall survival (OS), disease-free survival (DFS), melanoma recurrences, and toxicity. The quality of each trial was systematically evaluated. Nine randomized controlled trials (RCTs) of IFNalpha therapy in melanoma patients were identified. Eight were published and one was unpublished. Eight trials comprising 3,178 patients fulfilled our inclusion criteria and were analyzed. Quality assessment scores ranged from 22 to 71, with a mean score of 55.4 (95% confidence interval, 53.8 to 57.0). For OS, only one trial reported a statistically significant benefit for IFNalpha, but our analysis did not confirm it. Two trials reported statistically significant benefit in DFS for the patients treated with IFNalpha, but our analysis confirmed it in only one trial. There was a wide clinical heterogeneity between included trials, making meta-analysis inappropriate. In our review, results from included RCTs demonstrated no clear benefit of IFNalpha therapy on OS in melanoma patients. A large RCT is required to answer whether a full regimen of IFNalpha therapy is effective and to identify the subgroups of patients who might benefit from IFNalpha treatment.

SEN virus: Response to interferon alfa and influence on the severity and treatment response of coexistent hepatitis C

The SEN virus (SENV) is a recently identified single-stranded, circular DNA virus. A strong association between 2 SENV variants (SENV-D and SENV-H) and transfusion-associated non–A-to-E hepatitis has been reported. To clarify the effect of SENV infection on coexisting chronic hepatitis C and the effect of interferon alfa (IFN-α) therapy on SENV replication, SENV DNA was quantitated by polymerase chain reaction in serum samples from 186 patients with chronic hepatitis C. Thirty-nine of 186 (21%) patients with chronic hepatitis C were positive for SENV DNA. There were no differences in the clinical, virologic and histologic features between patients with and without SENV infection. Eighteen of 102 patients with chronic hepatitis C who received IFN-α were positive for SENV DNA. The sustained response rate for hepatitis C virus (HCV) clearance after IFN-α treatment did not differ significantly between patients with SENV (28%) and without SENV infection (39%). SENV DNA levels decreased during therapy in 15 of 16 patients, and 11 of the 16 patients (69%) had a sustained loss of SENV DNA in response to IFN-α. In coinfected patients, SENV responses to IFN-α were significantly better in those who failed to clear HCV RNA than in those who lost HCV RNA (P = .013). In conclusion, SENV infection was frequently found in patients with chronic hepatitis C. SENV infection had no apparent influence on the severity of HCV-related liver disease or the HCV response to IFN-α. SENV was sensitive to IFN-α therapy and the majority of patients had a sustained virologic response. (HEPATOLOGY 2002;35:953-959.)

Hepatic expression of hepatitis C virus RNA in chronic hepatitis C: A study by in situ reverse-transcription polymerase chain reaction

Hepatitis C virus (HCV) replicates at a low rate and this makes its detection and intrahepatic localization difficult. To evaluate the clinical implications and effect of interferon alfa (IFN-alpha) therapy on hepatic expression of HCV RNA, HCV RNA was detected by in situ reverse-transcription polymerase chain reaction (IS-RT-PCR) in formalin-fixed paraffin-embedded liver sections from 26 patients with chronic hepatitis C. Results were compared with RT-PCR of HCV RNA extracted from liver sections/tissue. Twenty-four paired post-IFN-alpha treatment biopsy specimens were also assessed. Using RT-PCR of the extracted RNA as a positive standard and non-HCV liver sections as the negative standard, the sensitivity and specificity of IS-RT-PCR were 69% and 100%, respectively. HCV RNA was detected in the cytoplasm of hepatocytes (median, 5% hepatocytes positive; range, 0 to 35%) and very occasionally in infiltrating mononuclear cells. There was no correlation between hepatic expression of HCV RNA and the clinical, biochemical parameters, total and activity scores of histology activity index. Presence of HCV RNA in liver as detected by IS-RT-PCR was associated with higher serum HCV RNA levels (4.9 x 106 vs. 0.4 x 106 genome Eq/mL, P < .01). There was no difference in the pretreatment proportion of HCV RNA-positive hepatocytes among patients with different biochemical responses to IFN-alpha therapy. In the posttreatment samples, HCV RNA was undetectable by IS-RT-PCR in 16 of 24 patients (P < .01), including all 4 patients who had complete and sustained response (SR). We conclude that HCV RNA was detected by IS-RT-PCR in 0 to 35% of hepatocytes in patients with chronic HCV infection, detection of HCV RNA in liver by IS-RT-PCR was associated with higher viremia levels and IFN-alpha therapy reduced hepatocytic expression of HCV RNA. (Hepatology 1996 Jun;23(6):1318-23)

Effect of interferon alfa on the dynamics of hepatitis C virus turnover in vivo

In about 30% to 40% of patients with chronic hepatitis C, treatment with recombinant interferon alfa (r-IFN alpha) causes a decrease of serum aminotransferases and hepatitis C virus (HCV) RNA. The antiviral mechanism of interferon alfa (IFN alpha) in vivo is unknown. From serial measurements of serum HCV-RNA concentrations following IFN alpha induced perturbation of the balance between virus production and clearance, we obtained kinetic information on the pretreatment steady-state of HCV. In patients with chronic hepatitis C responding to IFN alpha, HCV-RNA declined exponentially with a half life of approximately 2 days. Modeling of the data predicts that in patients with chronic hepatitis C responding to IFN alpha this cytokine predominantly acts as an inhibitor of de novo infection of susceptible cells. HCV is released from infected cells with a mean half life of 2.7 +/- 1.3 days, whereas the clearance rate from serum is faster (mean half life, 0.7 +/- 0.4 days). The minimum virus production and clearance per day in patients with chronic hepatitis C was calculated to be 6.7 x 1010 virions/d (range, 0.2 to 43.8 x 1010 virions/d). These values showed no correlation with the HCV genotype, aminotransferase levels, or the histological activity as assessed before the administration of r-IFN alpha. Simultaneous kinetic analysis of serum aminotransferases as surrogate markers of hepatocyte integrity revealed half lifes for the release of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) from hepatocytes of 4.7 +/- 3.8 and 3.0 +/- 3.5 days, respectively. The half life data for HCV in chronically infected patients are remarkably similar to recently published data on human immunodeficiency virus type 1 (HIV-1) suggesting that both RNA viruses replicate continuously and highly productive in vivo. The turnover rates explain the rapid generation of viral diversity and the opportunity for viral escape phenomena from the host immune surveillance. (Hepatology 1996 Feb;23(2):366-71)

Effect of interferon alfa on the dynamics of hepatitis C virus turnover in vivo

In about 30% to 40% of patients with chronic hepatitis C, treatment with recombinant interferon alfa (r-IFN alpha) causes a decrease of serum aminotransferases and hepatitis C virus (HCV) RNA. The antiviral mechanism of interferon alfa (IFN alpha) in vivo is unknown. From serial measurements of serum HCV-RNA concentrations following IFN alpha induced perturbation of the balance between virus production and clearance, we obtained kinetic information on the pretreatment steady-state of HCV. In patients with chronic hepatitis C responding to IFN alpha, HCV-RNA declined exponentially with a half life of approximately 2 days. Modeling of the data predicts that in patients with chronic hepatitis C responding to IFN alpha this cytokine predominantly acts as an inhibitor of de novo infection of susceptible cells. HCV is released from infected cells with a mean half life of 2.7 +/- 1.3 days, whereas the clearance rate from serum is faster (mean half life, 0.7 +/- 0.4 days). The minimum virus production and clearance per day in patients with chronic hepatitis C was calculated to be 6.7 x 10(10) virions/d (range, 0.2 to 43.8 x 10(10) virions/d). These values showed no correlation with the HCV genotype, aminotransferase levels, or the histological activity as assessed before the administration of r-IFN alpha. Simultaneous kinetic analysis of serum aminotransferases as surrogate markers of hepatocyte integrity revealed half lifes for the release of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) from hepatocytes of 4.7 +/- 3.8 and 3.0 +/- 3.5 days, respectively. The half life data for HCV in chronically infected patients are remarkably similar to recently published data on human immunodeficiency virus type 1 (HIV-1) suggesting that both RNA viruses replicate continuously and highly productive in vivo. The turnover rates explain the rapid generation of viral diversity and the opportunity for viral escape phenomena from the host immune surveillance.

Lymphoproliferative responses to hepatitis C virus core, E1, E2, and NS3 in patients with chronic hepatitis C infection treated with interferon alfa

The quality of the hepatitis C virus (HCV)-specific T-cell response may greatly determine the course of an HCV infection. An adequate T-cell response may contribute to a successful clearance of the virus and a rapid recovery from the disease. An inadequate response may lead to viral persistence and may eventually contribute to the pathogenesis of hepatocellular damage in chronic disease. The effect of interferon alfa (IFN-alpha), presently the most popular therapeutic agent for chronic HCV infections, on HCV-specific T-cell responses is completely unknown. To demonstrate the presence of HCV-specific T lymphocytes during chronic HCV infections, to know their antigenic specificities, and to examine possible effects of IFN-alpha treatment on their presence and antigen recognition patterns, we have stimulated peripheral blood mononuclear cells (PBMC) from 35 chronic HCV patients with nine pools of synthetic peptides representing the HCV Core, E1, and E2 proteins as well as with a recombinant NS3 protein. The proliferative responses of PBMC from 16 healthy control subjects toward these antigens were measured for comparison. Lymphoproliferative responses of patients with chronic HCV infections were assayed either before (in 10 patients), during (in 13 patients), or after (in 21 patients) treatment with IFN-alpha. The analysis showed that PBMC from most HCV patients consistently recognized the COOH-terminal part of the core protein. E1, E2, and NS3 were recognized less frequently. This recognition pattern was not related to the therapy with IFN-alpha nor to the clinical response of the patient toward this therapy. The response to the Core protein could be fine-mapped to the COOH-terminal region encompassing amino acids (aa) 73 to 92, 121 to 140, 145 to 164, and 157 to 176. (Hepatology 1996 Jan;23(1):8-16)

Expression of transforming growth factor alpha in the liver before and after interferon alfa therapy for chronic hepatitis B

The effect of interferon alfa (IFN-α) therapy on the expression of transforming growth factor alpha (TGF-α) in the liver during chronic hepatitis B was investigated. Serial liver biopsy specimens were evaluated from 35 patients who had participated in a randomized, controlled trial of recombinant human IFN-α for the treatment of chronic hepatitis B. Percutaneous liver biopsy specimens obtained before and 1 year after entry in the trial were sectioned and stained with a monoclonal antibody to TGF-α in an avidin-biotin-peroxidase-complex system. The expression of TGF-α in each section was evaluated blindly (with respect to treatment group and order of biopsies) and was numerically scored. There was no significant difference in TGF-α expression before or after therapy between 13 patients receiving daily IFN-α, 13 receiving alternate-day IFN-α, and 9 receiving no therapy. Sustained clearance of HBV-DNA and DNA polymerase activity occurred in 8 of 26 treated patients (“responders”); the 18 other patients were “nonresponders”. Expression of TGF-α before IFN-α therapy was significantly higher in responders than in nonresponders; after IFN-α therapy, TGF-α expression decreased significantly among responders compared with nonresponders and untreated controls. Thus, the level of expression of TGF-α in the liver, which was correlated with the severity of inflammation in the liver in this study, appeared to be predictive of the response to IFN-α therapy in chronic hepatitis B, with a higher level of expression indicating a greater likelihood that the patient would respond.

Expression of transforming growth factor alpha in the liver before and after interferon alfa therapy for chronic hepatitis B

The effect of interferon alfa (IFN-α) therapy on the expression of transforming growth factor alpha (TGF-α) in the liver during chronic hepatitis B was investigated. Serial liver biopsy specimens were evaluated from 35 patients who had participated in a randomized, controlled trial of recombinant human IFN-α for the treatment of chronic hepatitis B. Percutaneous liver biopsy specimens obtained before and 1 year after entry in the trial were sectioned and stained with a monoclonal antibody to TGF-α in an avidin-biotin-peroxidase-complex system. The expression of TGF-α in each section was evaluated blindly (with respect to treatment group and order of biopsies) and was numerically scored. There was no significant difference in TGF-α expression before or after therapy between 13 patients receiving daily IFN-α, 13 receiving alternate-day IFN-α, and 9 receiving no therapy. Sustained clearance of HBV-DNA and DNA polymerase activity occurred in 8 of 26 treated patients (“responders”); the 18 other patients were “nonresponders.” Expression of TGF-α before IFN-α therapy was significantly higher in responders than in nonresponders; after IFN-α therapy, TGF-α expression decreased significantly among responders compared with nonresponders and untreated controls. Thus, the level of expression of TGF-α in the liver, which was correlated with the severity of inflammation in the liver in this study, appeared to be predictive of the response to IFN-α therapy in chronic hepatitis B, with a higher level of expression indicating a greater likelihood that the patient would respond. (Hepatology 1995; 22:1021-1026.).

Effects of interferon alfa and gamma on human uveal melanoma cells in vitro.

Uveal melanoma is a tumour with a high incidence of metastasis and a high mortality rate. Additional therapies to obtain a better local control or an effective treatment of metastases are necessary. Interferons may be applied. The effects of human interferon alfa and gamma on proliferation and expression of immunologically important molecules of human uveal melanoma cells in vitro were studied. A propidium iodide assay was used to determine proliferation and immunostaining with monoclonal antibodies was applied to detect changes in antigen expression on two primary uveal melanoma cell lines, Mel 202 and 92-1. Interferon alfa inhibited proliferation of cell line 92-1 at a concentration of 50 IU/ml, but had no effect on cell line Mel 202, while interferon gamma inhibited growth of both cell lines. Only interferon gamma had a visible effect on cell morphology. With respect to the immunomodulatory effects, interferon alfa increased monomorphic HLA class I expression, but did not affect HLA class II expression. Interferon gamma induced not only HLA class I but also class II expression. The effects on HLA expression were locus-specific with the strongest effects observed for HLA-B and DR products. Small differences were observed with respect to the susceptibility of two different melanoma cell lines to antiproliferative effects and to modulation of antigen expression. The effects of interferon alfa and gamma on human uveal melanoma cells in vitro suggest a potential role of these cytokines in the treatment of patients with uveal melanoma. In particular, the immunomodulatory effects of these cytokines in vitro imply that treatment of patients with these cytokines might stimulate a beneficial antimelanoma immune response in vivo.

P-84 Effect of interferon alfa on serum markers for hepatic fibrosis in patients with chronic hepatitis C

P-84 Effect of interferon alfa on serum markers for hepatic fibrosis in patients with chronic hepatitis C

Effects of interferon-alfa and the herbal medicine Sho-saiko-to on cytokine production and lung fibroblast proliferation: A pilot study

Since interferon-alfa (IFN-α) and Sho-saiko-to (SST) are known to modulate immune responses, their immunological effects may be responsible for the induction of interstitial pneumonia. Additionally, fibroblasts play an important role in lung fibrosis. Therefore, the in vitro effects of IFN-α and/or SST on cytokine production of fibroblasts were examined. No difference in cytokine production was shown among natural IFN-α, IFN-α-2a, and IFN-α-2b. Fibroblasts from three control subjects and four patients with idiopathic pulmonary fibrosis (IPF) were used. Cells from the control and IPF groups produced interleukin-6 (IL-6) dose-dependently with either IFN-α or SST treatment. Combined administration of these agents produced greater IL-6 production. In all controls, interleukin-8 (IL-8) production by fibroblasts was increased with SST but suppressed with IFN-α. In contrast, in 2 of 4 IPF patients, IL-8 production was increased with IFN-α. More importantly, there was a greater production of IL-8 when stimulated with both IFN-α and SST in the IPF group. Proliferation of control and IPF fibroblasts was inhibited equally by each drug. These results suggest that fibroblast cytokine production, augmented by IFN-α and/or SST, may play a role in the development or exacerbation of interstitial pneumonia.

Exacerbation of Multiple Sclerosis After the Administration of Recombinant Human Interferon Alfa

To the Editor.— Interferons appear to have varying effects on multiple sclerosis according to their major types, designated as alfa, beta, or gamma. The administration of interferon alfa for systemic effect 1 and the intrathecal administration of interferon beta 2 have been reported to reduce the frequency and severity of exacerbations of multiple sclerosis, possibly because of antiviral properties. In contrast, the disease is exacerbated by administration of interferon gamma, hypothetically because this compound may potentiate immune response. 3 Contrary to a previous report, 1 we observed a patient in whom acute exacerbation of multiple sclerosis developed after he received interferon alfa (interferon alfa-2b [Intron A]) for chronic active non-A, non-B hepatitis. Report of a Case.— A 38-year-old man was included in a clinical trial assessing the effect of interferon alfa on chronic active non-A, non-B hepatitis in March 1988. The patient had been suffering from multiple sclerosis since 1976.