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Wang JH, Pianko MJ, Ke X, Herskovic A, Hershow R, Cotler SJ, Chen W, Chen ZW, Rong L. Characterization of antigenic variants of hepatitis C virus in immune evasion. Virol J 2011; 8:377. [PMID: 21801418 PMCID: PMC3158126 DOI: 10.1186/1743-422x-8-377] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 07/29/2011] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Antigenic variation is an effective way by which viruses evade host immune defense leading to viral persistence. Little is known about the inhibitory mechanisms of viral variants on CD4 T cell functions. RESULTS Using sythetic peptides of a HLA-DRB1*15-restricted CD4 epitope derived from the non-structural (NS) 3 protein of hepatitis C virus (HCV) and its antigenic variants and the peripheral blood mononuclear cells (PBMC) from six HLA-DRB1*15-positive patients chronically infected with HCV and 3 healthy subjects, the in vitro immune responses and the phenotypes of CD4+CD25+ cells of chronic HCV infection were investigated. The variants resulting from single or double amino acid substitutions at the center of the core region of the Th1 peptide not only induce failed T cell activation but also simultaneously up-regulate inhibitory IL-10, CD25-TGF-β+ Th3 and CD4+IL-10+ Tr1 cells. In contrast, other variants promote differentiation of CD25+TGF-β+ Th3 suppressors that attenuate T cell proliferation. CONCLUSIONS Naturally occuring HCV antigenic mutants of a CD4 epitope can shift a protective peripheral Th1 immune response into an inhibitory Th3 and/or Tr1 response. The modulation of antigenic variants on CD4 response is efficient and extensive, and is likely critical in viral persistence in HCV infection.
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Araújo ESA, Dahari H, Neumann AU, de Paula Cavalheiro N, Melo CE, de Melo ES, Layden TJ, Cotler SJ, Barone AA. Very early prediction of response to HCV treatment with PEG-IFN-alfa-2a and ribavirin in HIV/HCV-coinfected patients. J Viral Hepat 2011; 18:e52-60. [PMID: 20738775 PMCID: PMC3075977 DOI: 10.1111/j.1365-2893.2010.01358.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The objective of this study was to find very early viral kinetic markers to predict nonresponse to hepatitis C virus (HCV) therapy in a group of human immunodeficiency virus (HIV)/HCV-coinfected patients. Twenty-six patients (15 HCV genotype-1 and 11 genotype-3) were treated with a 48-week regimen of peginterferon-alfa-2a (PEG-IFN) (180 μg/week) and weight-based ribavirin (11 mg/kg/day). Samples were collected at baseline; 4, 8, 12, 18, 24, 30, 36 and 42 h; days 2, 3, 4, 7, 8, 15, 22, 29, 43 and 57 then weekly and monthly. Five patients discontinued treatment. Seven patients (27%) achieved a sustained virological response (SVR). Nadir HCV RNA levels were observed 1.6 ± 0.3 days after initiation of therapy, followed by a 0.3- to 12.9-fold viral rebound until the administration of the second dose of PEG-IFN, which were not associated with SVR or HCV genotype. A viral decline <1.19 log for genotype-1 and <0.97 log for genotype-3, 2 days after starting therapy, had a negative predictive value (NPV) of 100% for SVR. The day 2 virological response had a similar positive predictive value for SVR as a rapid virological response at week 4. In addition, a second-phase viral decline slope (i.e., measured from day 2 to 29) <0.3 log/week had a NPV = 100% for SVR. We conclude that first-phase viral decline at day 2 and second-phase viral decline slope (<0.3 log/week) are excellent predictors of nonresponse. Further studies are needed to validate these viral kinetic parameters as early on-treatment prognosticators of nonresponse in patients with HCV and HIV.
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de Araújo ESA, Dahari H, Cotler SJ, Layden TJ, Neumann AU, Melo CE, Barone AA. Pharmacodynamics of PEG-IFN-[alpha]-2a and HCV response as a function of IL28B polymorphism in HIV/HCV-coinfected patients. J Acquir Immune Defic Syndr 2011; 56:95-9. [PMID: 21157362 PMCID: PMC3066089 DOI: 10.1097/qai.0b013e3182020596] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We examined the association between IL28B single-nucleotide polymorphism rs12979860, hepatitis C virus (HCV) kinetic, and pegylated interferon alpha-2a pharmacodynamic parameters in HIV/HCV-coinfected patients from South America. Twenty-six subjects received pegylated interferon alpha-2a + ribavirin. Serum HCV-RNA and interferon concentrations were measured frequently during the first 12 weeks of therapy and analyzed using mathematical models. African Americans and whites had a similar distribution of IL28B genotypes (P = 0.5). The IL28B CC genotype was overrepresented (P = 0.015) in patients infected with HCV genotype-3 compared with genotype-1. In both genotype-1 and genotype-3, the first-phase viral decline and the average pegylated interferon-alpha-2a effectiveness during the first week of therapy were larger (trend P <= 0.12) in genotype-CC compared with genotypes-TC/TT. In genotype-1 patients, the second slower phase of viral decline (days 2-29) and infected cells loss rate, [delta], were larger (P = 0.02 and 0.11, respectively) in genotype-CC than in genotypes-TC/TT. These associations were not observed in genotype-3 patients.
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Tencate V, Sainz B, Cotler SJ, Uprichard SL. Potential treatment options and future research to increase hepatitis C virus treatment response rate. Hepat Med 2010; 2010:125-145. [PMID: 21331152 PMCID: PMC3039485 DOI: 10.2147/hmer.s7193] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Hepatitis C virus (HCV) is a liver-tropic blood-borne pathogen that affects more than 170 million people worldwide. Although acute infections are usually asymptomatic, up to 90% of HCV infections persist with the possibility of long-term consequences such as liver fibrosis, cirrhosis, steatosis, insulin resistance, or hepatocellular carcinoma. As such, HCV-associated liver disease is a major public health concern. Although the currently available standard of care therapy of pegylated interferon α plus ribavirin successfully treats infection in a subset of patients, the development of more effective, less toxic HCV antivirals is a health care imperative. This review not only discusses the limitations of the current HCV standard of care but also evaluates upcoming HCV treatment options and how current research elucidating the viral life cycle is facilitating the development of HCV-specific therapeutics that promise to greatly improve treatment response rates both before and after liver transplantation.
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Dahari H, Affonso de Araujo ES, Haagmans BL, Layden TJ, Cotler SJ, Barone AA, Neumann AU. Pharmacodynamics of PEG-IFN-alpha-2a in HIV/HCV co-infected patients: implications for treatment outcomes. J Hepatol 2010; 53:460-7. [PMID: 20561702 PMCID: PMC2956745 DOI: 10.1016/j.jhep.2010.03.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2009] [Revised: 02/11/2010] [Accepted: 03/20/2010] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS The pharmacokinetics and pharmacodynamics of pegylated-interferon-alpha-2a (PEG-IFN) have not been described in HCV/HIV co-infected patients. We sought to estimate the pharmacokinetics and pharmacodynamics of PEG-IFN and determine whether these parameters predict treatment outcome. METHODS Twenty-six HCV/human immunodeficiency virus (HIV)-co-infected patients were treated with a 48-week regimen of PEG-IFN (180 microg/week) plus ribavirin (11 mg/kg/day). HCV RNA and PEG-IFN concentrations were obtained from samples collected until week 12. A modeling framework that includes pharmacokinetic and pharmacodynamic parameters was developed. RESULTS Five patients discontinued treatment. Seven patients achieved a sustained virological response (SVR). PEG-IFN concentrations at day 8 were similar to steady-state levels (p=0.15) and overall pharmacokinetic parameters were similar in SVRs and non-SVRs. The maximum PEG-IFN effectiveness during the first PEG-IFN dose and the HCV-infected cell loss rate (delta), were significantly higher in SVRs compared to non-SVRs (median 95% vs. 86% [p=0.013], 0.27 vs. 0.11 day(-1) [p=0.006], respectively). Patients infected with HCV genotype 1 had a significantly lower average first-week PEG-IFN effectiveness (median 70% vs. 88% [p=0.043]), however, 4- to 12-week PEG-IFN effectiveness was not significantly different compared to those with genotype 3 (p=0.114). Genotype 1 had a significantly lower delta compared to genotype 3 (median 0.14 vs. 0.23 day(-1) [p=0.021]). The PEG-IFN concentration that decreased HCV production by 50% (EC(50)) was lower in genotype 3 compared to genotype 1 (median 1.3 vs. 3.4 [p=0.034]). CONCLUSIONS Both the HCV-infected cell loss rate (delta) and the maximum effectiveness of the first dose of PEG-IFN-alpha-2a characterised HIV co-infected patients and were highly predictive of SVR. Further studies are needed to validate these viral kinetic parameters as early on-treatment prognosticators of response in patients with HCV and HIV.
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Cotler SJ, Dhamija MK, Luc BJ, Siqueira F, Bartram AH, Layden TJ, Wong SS. The prevalence and clinical correlates of elevated ALT levels in an urban Chinatown community. J Viral Hepat 2010; 17:148-52. [PMID: 19674287 DOI: 10.1111/j.1365-2893.2009.01162.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Alanine aminotransferase (ALT) levels are a primary consideration in treatment decisions regarding hepatitis B virus (HBV) infection. Levels can be elevated as a result of HBV-related liver injury or to other causes. The aim of this study was to assess the background prevalence and clinical correlates of elevated ALT levels in Chinese immigrants who were HBsAg negative. Subjects consisted of adults seen in an urban Chinatown Internal Medicine practice between 1, 2006 and 12, 2007. Clinical information was collected retrospectively. An elevated ALT level was defined as >19 U/L for women and >30 U/L for men. The primary analysis focused on 2457 persons who were HBsAg negative. Their mean age was 55 +/- 18 years, 64% were female and 36% were obese. All subjects were ethnically Chinese and 96% were born in Asia. Thirty percent had an elevated ALT level. In univariate analysis, factors associated with elevated ALT included older age (P < 0.001), female gender (P = 0.001), obesity (P < 0.001), diabetes (P < 0.001), hypercholesterolemia (P < 0.001) and hypertension (P < 0.001). In multivariate analysis BMI, diabetes, female gender and hypercholesterolemia were significantly associated with elevated ALT level. An additional analysis focused on a group of patients who were HBsAg positive, HBeAg negative and had HBV-DNA levels <1000 copies/mL. Fifty percent had elevated ALT levels. In conclusion, elevated ALT levels are common among Chinese immigrants without HBV (30%) and are associated with features of the metabolic syndrome. Liver biopsy should be performed in selected patients with HBV to distinguish the cause of ALT elevation before initiating antiviral therapy.
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Kallwitz ER, Layden-Almer J, Dhamija M, Berkes J, Guzman G, Lepe R, Cotler SJ, Layden TJ. Ethnicity and body mass index are associated with hepatitis C presentation and progression. Clin Gastroenterol Hepatol 2010; 8:72-8. [PMID: 19686868 DOI: 10.1016/j.cgh.2009.08.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 07/21/2009] [Accepted: 08/05/2009] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Ethnicity and the metabolic syndrome are believed to affect progression of hepatitis C virus (HCV) infection, but the interaction between these factors is unknown. We evaluated the association between elements of the metabolic syndrome and ethnicity in the histologic progression of HCV in a large, diverse cohort. METHODS We retrospectively evaluated clinical data and liver biopsy samples from 812 patients who had no cause of liver disease other than HCV infection. Liver biopsies were scored for steatosis, necroinflammatory activity, and fibrosis. For each patient with a known risk factor for viral acquisition, fibrosis index was calculated as an indicator of disease progression. RESULTS Hispanics had significantly higher fibrosis index (0.13 +/- 0.09) than non-Hispanic whites (0.11 +/- 0.07) and African Americans (0.10 +/- 0.06; P = .001). Fibrosis index correlated with body mass index (BMI), older age at infection, ethnicity, and degree of steatosis. Cirrhosis was present in 50% of Hispanics, 38% of non-Hispanic whites, and 24% of African Americans (P < .001). The presence of cirrhosis was associated additionally with older age, longer duration of infection, BMI, alcohol consumption, and diabetes. In multivariate analysis, only BMI and ethnicity were associated with both fibrosis index and presentation with cirrhosis. Patients with higher BMIs, diabetes mellitus, and steatosis had higher degrees of necroinflammation. CONCLUSIONS Ethnicity and BMI each were associated with the progression of fibrosis and the presence of cirrhosis. Hispanics had the highest fibrosis index and prevalence of cirrhosis, whereas African Americans had the lowest. Ethnic differences in fibrosis index and cirrhosis persisted after controlling for elements of metabolic syndrome.
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TenCate V, Cotler SJ. Antiviral therapy as an adjunct to passive-active immunotherapy for prevention of perinatal transmission of HBV. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11901-009-0019-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Cotler SJ, Dhamija MK, Siqueira F, Bartram AH, Luc BJ, Layden TJ, Wong SS. Hepatitis B seroprevalence and disease characteristics in an urban Chinatown community. Clin Gastroenterol Hepatol 2009; 7:776-80. [PMID: 19344787 DOI: 10.1016/j.cgh.2009.03.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 03/18/2009] [Accepted: 03/21/2009] [Indexed: 01/06/2023]
Abstract
BACKGROUND & AIMS Chronic HBV infection is prevalent among Asian immigrants and is an important cause of cirrhosis and hepatocellular carcinoma. The aim of this study was to evaluate the HBsAg seroprevalence and to characterize hepatitis B in persons who presented to an urban Chinatown internal medicine practice. METHODS Records were reviewed retrospectively from 4671 adult patients who had at least 1 office visit during a 2-year period. Demographic information and laboratory data were collected. An elevated ALT level was defined as >19 IU/mL for women and >30 IU/mL for men. RESULTS All patients were ethnically Chinese, and 97% were born in Asia. HBsAg testing was available in 64% (3012/4671) of cases. The HBsAg seroprevalence rate was 11.1% (335/3012) overall and 14.9% in persons aged 30-39 years. HBeAg testing was available for 75% (250/335) of HBsAg+ cases. Seventy-five percent (188/250) were HBeAg-. Sixty percent (26/43) of HBeAg+ patients with available data had HBV DNA >10(5) copies/mL and an elevated ALT level. Sixteen percent (21/128) of HBeAg- patients with available data had HBV DNA >10(4) copies/mL and an elevated ALT level. CONCLUSIONS The HBsAg seroprevalence was high (11.1%) in Chinese immigrants presenting for general medical care. A majority (75%) of HBsAg+ patients were HBeAg-. Sixty percent of HBeAg+ cases and 16% of HBeAg- patients with available data had both HBV DNA and ALT levels that would prompt consideration of antiviral therapy. These findings highlight the importance of testing and medical management of hepatitis B in Chinese Americans.
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Wang JH, Zheng X, Ke X, Dorak MT, Shen J, Boodram B, O'Gorman M, Beaman K, Cotler SJ, Hershow R, Rong L. Ethnic and geographical differences in HLA associations with the outcome of hepatitis C virus infection. Virol J 2009; 6:46. [PMID: 19409091 PMCID: PMC2679741 DOI: 10.1186/1743-422x-6-46] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Accepted: 05/01/2009] [Indexed: 01/12/2023] Open
Abstract
Backgrounds The association of human leukocyte antigen (HLA) genes with the outcome of hepatitis C virus (HCV) infection may be modified by ethnic and geographical differences. Results HLA-A, -C, -DRB1 and -DQB1 genotyping were performed in a Midwestern American cohort of 105 HCV infected subjects among which 49 cleared HCV infection and 56 had persistent viral infection. A new protective association of HLA-Cw*05 to HCV infection of all ethnic populations was identified (OR = 0.12, 95% CI = 0.01–0.97, P = 0.03). It was surprising that HLA-A*02 (P for interaction = 0.02) and HLA-DRB1*12 (P for interaction = 0.05) showed statistical interaction with race indicating opposite associations in Caucasians (OR = 2.74 for A*02 and 2.15 for DRB1*12) and non-Caucasians (OR = 0.41 for A*02 and 0.15 for DRB1*12). In addition, HLA-DRB1*01 (OR = 0.26), DQB1*05 (OR = 0.23) and the haplotype DRB1*01-DQB1*05 (OR = 0.19) showed strong associations with viral clearance in Caucasians. The protective associations of A*03 (OR = 0.20) and DQB1*03 (OR = 0.20) were exclusive to non-Caucasians. In contrast, DQB1*02 (OR = 2.56, 95% CI = 1.15–7.71, P = 0.02) and the haplotype DRB1*07-DQB1*02 (OR = 5.25, 95% CI = 1.04–26.6, P = 0.03) were risk markers in Caucasians. Conclusion The associations of HLA-A*02 and HLA-DRB1*12 with HCV infection are opposite with different races. HLA-A*03, Cw*05, DRB1*01, DQB1*03 and DQB1*05 are associated with viral clearance while HLA-DRB1*07 and DQB1*02 are risk markers for viral persistence of HCV infection in Midwestern Americans. These results reveal ethnically and geographically different distribution of HLA-genes which are associated with the outcome of HCV infection.
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Dahari H, Cotler SJ, Layden TJ, Perelson AS. Hepatitis B virus clearance rate estimates. Hepatology 2009; 49:1779-80; author reply 1780-1. [PMID: 19402118 DOI: 10.1002/hep.22874] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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Dahari H, Shudo E, Cotler SJ, Layden TJ, Perelson AS. Modelling Hepatitis C virus Kinetics: The Relationship between the Infected Cell Loss rate and the Final Slope of Viral Decay. Antivir Ther 2009. [DOI: 10.1177/135965350901400306] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background Patients infected with hepatitis C virus (HCV) who respond to treatment with interferon-α plus ribavirin exhibit biphasic or triphasic viral load decreases. While the rapid first phase is indicative of the effectiveness of therapy in blocking viral production (e), the slope of the final phase ( X), that is, the second phase in biphasic decreases and the third phase in triphasic decreases, depends on the infected cell loss rate (δ). In standard models, X is approximately εδ when the viral clearance rate c>>δ, as has been previously estimated. Methods The relationship among e, S, X and the baseline fraction of HCV-infected hepatocytes (π) was investigated in a model that included proliferation of hepatocytes. Results We found that X was not proportional to e, but rather obeyed a complex relationship that could lead to dramatic increases in estimates of 8 as e increased. In particular, when ε<99%, X moderately underestimated 8 in patients with a small π, whereas δ might be up to 10-fold larger than λ in patients with a large π. Interestingly, when ε>99%, δ∼λ regardless of π. Conclusions Our results indicated that in patients undergoing therapy who achieved a 2 log10 reduction in viral load (ε<99%), previously estimated δ values might represent only a minimal estimate of the infected cell loss rate. Moreover, combining interferon-α with new antiviral agents to achieve ε>99% should allow for a more accurate estimate of 8 in HCV RNA kinetic studies. This might be important when using viral kinetics to estimate the effect of the immune response on viral elimination and the attainment of sustained virological response.
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Dahari H, Layden-Almer JE, Kallwitz E, Ribeiro RM, Cotler SJ, Layden TJ, Perelson AS. A mathematical model of hepatitis C virus dynamics in patients with high baseline viral loads or advanced liver disease. Gastroenterology 2009; 136:1402-9. [PMID: 19208338 PMCID: PMC2883911 DOI: 10.1053/j.gastro.2008.12.060] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Revised: 12/08/2008] [Accepted: 12/22/2008] [Indexed: 12/21/2022]
Abstract
BACKGROUND & AIMS Patients with baseline hepatitis C virus-RNA levels (bHCV-RNA)>6 log IU/mL or cirrhosis have a reduced probability of a sustained-virologic response (SVR). We examined the relation between bHCV-RNA, cirrhosis, and SVR with a mathematical model that includes the critical-drug efficacy (epsilonc; the efficacy required for a drug to clear HCV), the infection-rate constant (beta), and the percentage of HCV-infected hepatocytes (pi). METHODS The relation between baseline factors and SVR was evaluated in 1000 in silico HCV-infected patients, generated by random assignment of realistic host and viral kinetic parameters. Model predictions were compared with clinical data from 170 noncirrhotic and 75 cirrhotic patients. RESULTS The ranges chosen for beta and the viral production rate (p) resulted in bHCV-RNA levels that were in agreement with the distribution observed in US patients. With these beta and p values, higher bHCV-RNA levels led to higher epsilonc, resulting in lower SVR rates. However, higher beta values resulted in lower bHCV-RNA levels but higher pi and (epsilonc), predicting lower rates of SVR. Cirrhotic patients had lower bHCV-RNA levels than noncirrhotic patients (P=.013), and more had bHCV-RNA levels<6 log IU/mL (P<.001). Even cirrhotic patients with lower bHCV-RNA levels had lower SVR rates. An increase in beta could explain the results observed in cirrhotic patients. CONCLUSIONS Our model predicts that higher bHCV-RNA levels lead to higher epsilonc, reducing the chance of achieving SVR; cirrhotic patients have lower SVR rates because of large pi values, caused by increased rates of hepatocyte infection.
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Dahari H, Shudo E, Cotler SJ, Layden TJ, Perelson AS. Modelling hepatitis C virus kinetics: the relationship between the infected cell loss rate and the final slope of viral decay. Antivir Ther 2009; 14:459-464. [PMID: 19474480 PMCID: PMC2874964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BACKGROUND Patients infected with hepatitis C virus (HCV) who respond to treatment with interferon-alpha plus ribavirin exhibit biphasic or triphasic viral load decreases. While the rapid first phase is indicative of the effectiveness of therapy in blocking viral production (epsilon), the slope of the final phase (lambda), that is, the second phase in biphasic decreases and the third phase in triphasic decreases, depends on the infected cell loss rate (delta). In standard models, lambda is approximately epsilondelta when the viral clearance rate c>>delta, as has been previously estimated. METHODS The relationship among epsilon, delta, lambda and the baseline fraction of HCV-infected hepatocytes (pi) was investigated in a model that included proliferation of hepatocytes. RESULTS We found that lambda was not proportional to epsilon, but rather obeyed a complex relationship that could lead to dramatic increases in estimates of delta as epsilon increased. In particular, when epsilon<99%, lambda moderately underestimated delta in patients with a small pi, whereas delta might be up to 10-fold larger than lambda in patients with a large pi. Interestingly, when epsilon>99%, delta approximately lambda regardless of pi. CONCLUSIONS Our results indicated that in patients undergoing therapy who achieved a 2 log(10) reduction in viral load (epsilon<99%), previously estimated delta values might represent only a minimal estimate of the infected cell loss rate. Moreover, combining interferon-alpha with new antiviral agents to achieve epsilon>99% should allow for a more accurate estimate of delta in HCV RNA kinetic studies. This might be important when using viral kinetics to estimate the effect of the immune response on viral elimination and the attainment of sustained virological response.
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Guzman G, Brunt EM, Petrovic LM, Chejfec G, Layden TJ, Cotler SJ. Does nonalcoholic fatty liver disease predispose patients to hepatocellular carcinoma in the absence of cirrhosis? Arch Pathol Lab Med 2008; 132:1761-6. [PMID: 18976012 DOI: 10.5858/132.11.1761] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2008] [Indexed: 11/06/2022]
Abstract
CONTEXT Hepatocellular carcinoma (HCC) is recognized as a complication of cirrhosis related to nonalcoholic fatty liver disease (NAFLD). Diabetes and the metabolic syndrome are also associated with HCC. However, it is not clear whether NAFLD predisposes patients to HCC in the absence of cirrhosis. OBJECTIVE To seek evidence that HCC can develop in NAFLD unaccompanied by cirrhosis. DESIGN Retrospective case study was performed on cases from 2004 to 2007 at the University of Illinois at Chicago Medical Center, using the key words hepatocellular carcinoma, liver explant, and liver resection. The diagnosis of HCC was identified and confirmed by hematoxylin-eosin-stained slides in 50 cases. Cause of liver disease was determined by review of liver histology, clinical history, and laboratory data. RESULTS Three patients presented with advanced HCC with features of metabolic syndrome, including an elevated body mass index. Each patient had bland steatosis on liver biopsy, without fibrosis or cirrhosis. None of the 3 patients had evidence of any cause for liver disease other than NAFLD. CONCLUSIONS The cases presented here suggest that NAFLD may predispose patients to HCC in the absence of cirrhosis. Further studies are needed to confirm this potentially important observation.
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Guzman G, Brunt EM, Petrovic LM, Chejfec G, Layden TJ, Cotler SJ. Does nonalcoholic fatty liver disease predispose patients to hepatocellular carcinoma in the absence of cirrhosis? Arch Pathol Lab Med 2008. [PMID: 18976012 DOI: 10.1043/1543-2165-132.11.1761] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
CONTEXT Hepatocellular carcinoma (HCC) is recognized as a complication of cirrhosis related to nonalcoholic fatty liver disease (NAFLD). Diabetes and the metabolic syndrome are also associated with HCC. However, it is not clear whether NAFLD predisposes patients to HCC in the absence of cirrhosis. OBJECTIVE To seek evidence that HCC can develop in NAFLD unaccompanied by cirrhosis. DESIGN Retrospective case study was performed on cases from 2004 to 2007 at the University of Illinois at Chicago Medical Center, using the key words hepatocellular carcinoma, liver explant, and liver resection. The diagnosis of HCC was identified and confirmed by hematoxylin-eosin-stained slides in 50 cases. Cause of liver disease was determined by review of liver histology, clinical history, and laboratory data. RESULTS Three patients presented with advanced HCC with features of metabolic syndrome, including an elevated body mass index. Each patient had bland steatosis on liver biopsy, without fibrosis or cirrhosis. None of the 3 patients had evidence of any cause for liver disease other than NAFLD. CONCLUSIONS The cases presented here suggest that NAFLD may predispose patients to HCC in the absence of cirrhosis. Further studies are needed to confirm this potentially important observation.
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Kallwitz ER, Cotler SJ. Is percutaneous liver biopsy safe in patients with hepatitis C and end-stage renal disease? NATURE CLINICAL PRACTICE. GASTROENTEROLOGY & HEPATOLOGY 2008; 5:420-421. [PMID: 18594495 DOI: 10.1038/ncpgasthep1183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 03/31/2008] [Indexed: 05/26/2023]
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Kallwitz ER, Kumar M, Aggarwal R, Berger R, Layden-Almer J, Gupta N, Cotler SJ. Ethnicity and nonalcoholic fatty liver disease in an obesity clinic: the impact of triglycerides. Dig Dis Sci 2008; 53:1358-63. [PMID: 18347982 DOI: 10.1007/s10620-008-0234-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Accepted: 06/20/2007] [Indexed: 12/23/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a growing problem that is associated with the metabolic syndrome. The goal of the present study was to evaluate for ethnic differences in NAFLD and clinical correlates of NAFLD. The study population consisted of 567 patients seen at an urban obesity clinic. Elevated aminotransferase levels were used as a surrogate marker for NAFLD. The prevalence of elevated aminotransferases was highest in Hispanics (39%), followed by Caucasians (28%), and African Americans (12%). In univariate analysis, elevated aminotransferase levels were associated with ethnicity (Hispanic > African American, P < 0.001, and Caucasian > African American P = 0.030), hypertriglyceridemia (P < 0.001), and male gender (P < 0.001). The pattern of results was confirmed in multivariate analysis, except that the differences between Caucasians and African Americans was no longer significant. In conclusion, in an obesity clinic population, elevated aminotransferase levels and hypertriglyceridemia were most common in Hispanics and least common in African Americans.
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Cotler SJ, Hay N, Xie H, Chen ML, Xu PZ, Layden TJ, Guzman G. Immunohistochemical expression of components of the Akt-mTORC1 pathway is associated with hepatocellular carcinoma in patients with chronic liver disease. Dig Dis Sci 2008; 53:844-9. [PMID: 17763954 DOI: 10.1007/s10620-007-9934-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Accepted: 07/09/2007] [Indexed: 12/21/2022]
Abstract
UNLABELLED Activation of the Akt-mTORC1 signaling pathway was evaluated in premalignant and hepatocellular carcinoma (HCC) lesions by assessing the expression of pS6, an Akt effector, and PTEN, an Akt suppressor. METHODS Immunohistochemical staining for pS6 and PTEN was performed on liver tissue from 52 patients with cirrhosis, with and without HCC. Two pathologists independently evaluated pS6 staining on a semiquantitative scale and categorized PTEN staining as present or absent. RESULTS In the HCC group, pS6 staining was greatest in HCC, followed by dysplasia, and benign cirrhotic tissue (P < 0.001). pS6 staining was greater in cirrhotic tissue from patients with HCC compared to cirrhosis in patients without HCC (P = 0.03). PTEN staining in tumor was absent in 8/33 (24%) cases. Loss of PTEN expression was more common in patients with higher tumor stage, compared to those with stage 1 tumors (P = 0.04). CONCLUSION Immunohistochemical evidence of activation of the Akt-mTORC1 pathway is associated with HCC.
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96
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Guzman G, Cotler SJ, Lin AY, Maniotis AJ, Folberg R. A pilot study of vasculogenic mimicry immunohistochemical expression in hepatocellular carcinoma. Arch Pathol Lab Med 2008; 131:1776-81. [PMID: 18081435 DOI: 10.5858/2007-131-1776-apsovm] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2007] [Indexed: 11/06/2022]
Abstract
CONTEXT The "de novo" formation of fluid-conducting patterns by tumor cells, termed vasculogenic mimicry (VM), is associated with increased mortality in many different solid tumors. OBJECTIVE To identify VM patterns in hepatocellular carcinoma (HCC) and to determine whether these patterns were associated with more rapid tumor recurrence after orthotopic liver transplantation. DESIGN Subjects included 20 patients who underwent orthotopic liver transplantation and were found to have HCC in the liver explant. Samples from 5 normal postmortem livers and 5 explanted livers with hepatitis C virus cirrhosis without HCC served as control tissues. Patterned matrix VM expression in HCC was identified by the presence of laminin-positive loops surrounding packets of tumor cells. Time to HCC recurrence after orthotopic liver transplantation was compared between patients with and without patterned VM expression. The relationships among VM in HCC, cause of chronic liver disease, serum alpha-fetoprotein level at the time of diagnosis, tissue expression by epidermal growth factor receptor, and endothelial markers including vascular endothelial growth factor and CD31 were assessed. RESULTS Patterned matrix VM was identified in 11 of 20 primary HCC tissue samples. Vasculogenic mimicry was absent in all 10 control cases and was not identified in any area of dysplasia. The expression of VM in HCC lesions in liver explants was associated with more rapid posttransplant recurrence (P = .01). Vasculogenic mimicry was not associated with the cause of liver disease, serum alpha-fetoprotein level at time of diagnosis, or expression of epidermal growth factor receptor, vascular endothelial growth factor, or CD31. CONCLUSIONS Vasculogenic mimicry of the patterned matrix type is present in hepatocellular carcinoma and is associated with tumor recurrence after orthotopic liver transplantation. Vasculogenic mimicry lesions are not associated with endothelial markers in HCC.
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Kallwitz ER, McLachlan A, Cotler SJ. Role of peroxisome proliferators-activated receptors in the pathogenesis and treatment of nonalcoholic fatty liver disease. World J Gastroenterol 2008; 14:22-8. [PMID: 18176957 PMCID: PMC2673387 DOI: 10.3748/wjg.14.22] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and can result in nonalcoholic steatohepatitis (NASH) and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of literature implicates the peroxisome proliferators-activated receptors (PPARs) in the pathogenesis and treatment of NAFLD. These nuclear hormone receptors impact on hepatic triglyceride accumulation and insulin resistance. The aim of this review is to describe the data linking PPARα and PPARγ to NAFLD/NASH and to discuss the use of PPAR ligands for the treatment of NASH.
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98
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Ko C, Siddaiah N, Berger J, Gish R, Brandhagen D, Sterling RK, Cotler SJ, Fontana RJ, McCashland TM, Han SHB, Gordon FD, Schilsky ML, Kowdley KV. Prevalence of hepatic iron overload and association with hepatocellular cancer in end-stage liver disease: results from the National Hemochromatosis Transplant Registry. Liver Int 2007; 27:1394-401. [PMID: 17927713 DOI: 10.1111/j.1478-3231.2007.01596.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND It is unclear whether mild to moderate iron overload in liver diseases other than hereditary haemochromatosis (HH) contributes to hepatocellular carcinoma. This study examined the association between hepatic iron grade and hepatocellular carcinoma in patients with end-stage liver disease of diverse aetiologies. METHODS The prevalence of hepatic iron overload and hepatocellular carcinoma was examined in 5224 patients undergoing liver transplantation. Explant pathology reports were reviewed for the underlying pathological diagnosis, presence of hepatocellular carcinoma and degree of iron staining. The distribution of categorical variables was studied using chi(2) tests. RESULTS Both iron overload and hepatocellular carcinoma were the least common with biliary cirrhosis (1.8 and 2.8% respectively). Hepatocellular carcinoma was the most common in patients with hepatitis B (16.7%), followed by those with hepatitis C (15.1%) and HH (14.9%). In the overall cohort, any iron overload was significantly associated with hepatocellular carcinoma (P=0.001), even after adjustment for the underlying aetiology of liver disease. The association between hepatic iron content and hepatocellular carcinoma was the strongest in patients with biliary cirrhosis (P<0.001) and hepatitis C (P<0.001). CONCLUSIONS Iron overload is associated with hepatocellular carcinoma in patients with end-stage liver disease, suggesting a possible carcinogenic or cocarcinogenic role for iron in chronic liver disease.
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Cotler SJ, Kallwitz E, TenCate V, Bhushan A, Berkes J, Benedetti E, Layden-Almer J, Layden TJ, Valyi-Nagy T, Guzman G. Diabetes and Hepatic Oxidative Damage Are Associated With Hepatitis C Progression After Liver Transplantation. Transplantation 2007; 84:587-91. [PMID: 17876270 DOI: 10.1097/01.tp.0000279003.40279.0e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Posttransplant diabetes mellitus (PTDM) is common after liver transplantation and was recently identified as a risk factor for hepatitis C progression. Increased levels of oxidative stress have been identified in diabetes and hepatitis C. The aim of this study was to evaluate the relationship among PTDM, oxidative damage in liver biopsy specimens, and fibrosis progression posttransplant. METHODS Subjects consisted of 27 hepatitis C-infected liver transplant recipients who had liver biopsy specimens available from 49 protocol liver biopsies. Paraffin embedded liver tissue sections were stained for 8-hydroxy-2' deoxyguanosine (8-OHdG), an indicator of hydroxyl radical mediated tissue damage. The percentage of cells staining for 8-OHdG in a histologic section was categorized as high (>66%) versus low score (< or =66%). Fibrosis index was calculated as fibrosis score (0-4)/ years posttransplant. Time to bridging fibrosis or cirrhosis (F3-4) was compared as a function of PTDM and 8-OHdG score. RESULTS Considering all 49 biopsies, fibrosis index was higher in cases with PTDM (P<0.001) and high 8-OHdG score (P=0.004). High 8-OHdG score was associated with PTDM (P=0.012). In time to event analyses, time to F3-4 was more rapid in patients with PTDM (P=0.02) and in those with high 8-OHdG scores (P<0.001). CONCLUSIONS This study confirmed a relationship between PTDM and hepatitis C fibrosis progression and found that oxidative damage in liver biopsy specimens was associated with PTDM and more rapid development of advanced fibrosis.
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Kallwitz ER, Cotler SJ. Screening for hepatocellular carcinoma in clinical practice: miles to go before we sleep. J Clin Gastroenterol 2007; 41:729-30. [PMID: 17700420 DOI: 10.1097/mcg.0b013e3180544951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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