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Dive into the research topics where Theo Heller is active.

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Featured researches published by Theo Heller.


Biology of Blood and Marrow Transplantation | 2005

National Institutes of Health consensus development project on criteria for clinical trials in chronic graft-versus-host disease: I. Diagnosis and staging working group report.

Madan Jagasia; Hildegard Greinix; Mukta Arora; Kirsten M. Williams; Daniel Wolff; Edward W. Cowen; Jeanne Palmer; Daniel J. Weisdorf; Nathaniel S. Treister; Guang Shing Cheng; Holly Kerr; Pamela Stratton; Rafael F. Duarte; George B. McDonald; Yoshihiro Inamoto; Afonso Celso Vigorito; Sally Arai; Manuel B. Datiles; David A. Jacobsohn; Theo Heller; Carrie L. Kitko; Sandra A. Mitchell; Paul J. Martin; Howard M. Shulman; Roy S. Wu; Corey Cutler; Georgia B. Vogelsang; Stephanie J. Lee; Steven Z. Pavletic; Mary E.D. Flowers

The 2005 National Institutes of Health (NIH) Consensus Conference proposed new criteria for diagnosing and scoring the severity of chronic graft-versus-host disease (GVHD). The 2014 NIH consensus maintains the framework of the prior consensus with further refinement based on new evidence. Revisions have been made to address areas of controversy or confusion, such as the overlap chronic GVHD subcategory and the distinction between active disease and past tissue damage. Diagnostic criteria for involvement of mouth, eyes, genitalia, and lungs have been revised. Categories of chronic GVHD should be defined in ways that indicate prognosis, guide treatment, and define eligibility for clinical trials. Revisions have been made to focus attention on the causes of organ-specific abnormalities. Attribution of organ-specific abnormalities to chronic GVHD has been addressed. This paradigm shift provides greater specificity and more accurately measures the global burden of disease attributed to GVHD, and it will facilitate biomarker association studies.


Hepatology | 2004

A pilot study of pioglitazone treatment for nonalcoholic steatohepatitis

Kittichai Promrat; Glen Lutchman; Gabriel I. Uwaifo; Renee J. Freedman; Alejandro Soza; Theo Heller; Edward Doo; Marc G. Ghany; Ahalya Premkumar; Yoon Park; T. Jake Liang; Jack A. Yanovski; David E. Kleiner; Jay H. Hoofnagle

Nonalcoholic steatohepatitis (NASH) is a common chronic liver disease for which there is no known effective therapy. A proportion of patients with NASH progress to advanced fibrosis and cirrhosis. NASH is considered one of the clinical features of the metabolic syndrome in which insulin resistance plays a central role. This prospective study evaluates the role of insulin‐sensitizing agent in treatment of NASH. Eighteen nondiabetic patients with biopsy‐proven NASH were treated with pioglitazone (30 mg daily) for 48 weeks. Tests of insulin sensitivity and body composition as well as liver biopsies were performed before and at the end of treatment. By 48 weeks, serum alanine aminotransferase values fell to normal in 72% of patients. Hepatic fat content and size as determined by magnetic resonance imaging decreased, and glucose and free fatty acid sensitivity to insulin were uniformly improved. Histological features of steatosis, cellular injury, parenchymal inflammation, Mallory bodies, and fibrosis were significantly improved from baseline (all P < 0.05). Using strict criteria, histological improvement occurred in two‐thirds of patients. Pioglitazone was well tolerated; the main side effects were weight gain (averaging 4%) and an increase in total body adiposity. In conclusion, these results indicate that treatment with an insulin‐sensitizing agent can lead to improvement in biochemical and histological features of NASH and support the role of insulin resistance in the pathogenesis of this disease. The long‐term safety and benefits of pioglitazone require further study. (HEPATOLOGY 2004;39:188–196.)


The New England Journal of Medicine | 2010

Residual NADPH Oxidase and Survival in Chronic Granulomatous Disease

Douglas B. Kuhns; W. Gregory Alvord; Theo Heller; Jordan J. Feld; Kristen M. Pike; Beatriz E. Marciano; Gulbu Uzel; Suk See DeRavin; Debra A. Long Priel; Benjamin P. Soule; Kol A. Zarember; Harry L. Malech; Steven M. Holland; John I. Gallin

BACKGROUND Failure to generate phagocyte-derived superoxide and related reactive oxygen intermediates (ROIs) is the major defect in chronic granulomatous disease, causing recurrent infections and granulomatous complications. Chronic granulomatous disease is caused by missense, nonsense, frameshift, splice, or deletion mutations in the genes for p22(phox), p40(phox), p47(phox), p67(phox) (autosomal chronic granulomatous disease), or gp91(phox) (X-linked chronic granulomatous disease), which result in variable production of neutrophil-derived ROIs. We hypothesized that residual ROI production might be linked to survival in patients with chronic granulomatous disease. METHODS We assessed the risks of illness and death among 287 patients with chronic granulomatous disease from 244 kindreds. Residual ROI production was measured with the use of superoxide-dependent ferricytochrome c reduction and flow cytometry with dihydrorhodamine oxidation assays. Expression of NADPH oxidase component protein was detected by means of immunoblotting, and the affected genes were sequenced to identify causal mutations. RESULTS Survival of patients with chronic granulomatous disease was strongly associated with residual ROI production as a continuous variable, independently of the specific gene affected. Patients with mutations in p47(phox) and most missense mutations in gp91(phox) (with the exception of missense mutations in the nucleotide-binding and heme-binding domains) had more residual ROI production than patients with nonsense, frameshift, splice, or deletion mutations in gp91(phox). After adolescence, mortality curves diverged according to the extent of residual ROI production. CONCLUSIONS Patients with chronic granulomatous disease and modest residual production of ROI have significantly less severe illness and a greater likelihood of long-term survival than patients with little residual ROI production. The production of residual ROI is predicted by the specific NADPH oxidase mutation, regardless of the specific gene affected, and it is a predictor of survival in patients with chronic granulomatous disease. (Funded by the National Institutes of Health.).


Hepatology | 2007

The effects of discontinuing pioglitazone in patients with nonalcoholic steatohepatitis

Glen Lutchman; Apurva A. Modi; David E. Kleiner; Kittichai Promrat; Theo Heller; Marc G. Ghany; Brian B. Borg; Rohit Loomba; T. Jake Liang; Ahalya Premkumar; Jay H. Hoofnagle

A pilot study of a 48‐week course of pioglitazone demonstrated significant improvements in the biochemical and histological features of nonalcoholic steatohepatitis (NASH). The aim of the study was to assess the effects of stopping pioglitazone. Twenty‐one patients with NASH were treated with pioglitazone (30 mg/day) for 48 weeks and underwent baseline and end‐of‐treatment evaluation including liver biopsy. Thirteen patients were followed for at least 48 weeks after stopping therapy and 9 underwent repeat liver biopsy. Statistical comparisons were made to evaluate whether discontinuation of pioglitazone resulted in a reversal of improvements seen on therapy. Stopping pioglitazone was associated with subsequent elevation in serum alanine aminotransferase levels (from 34 ± 13 to 70 ± 39 IU/l), decrease in adiponectin (from 9.7 ± 9.1 to 5.1 ± 4.5 μg/ml), worsening insulin sensitivity (HOMA Index: from 2.9 ± 1.8 to 5.5 ± 5.4), and increase in total hepatic fat (from 30% ± 32% to 71% ± 33%) despite no change in average body weight compared to the end of treatment. Repeat liver biopsy in 9 patients revealed significant worsening of parenchymal inflammation (from 1.2 ± 0.7 to 2.9 ± 1.1) and steatosis (from 0.9 ± 0.6 to 2.1 ± 1.3) but no change in fibrosis (from 1.1 ± 1.2 to 1.2 ± 1.3). NASH was again present on liver biopsy in 7 patients. Conclusion: These findings suggest that long‐term therapy with pioglitazone may be necessary to maintain improvements in disease activity in patients with NASH, although weight gain during treatment may ultimately limit its beneficial effects. (HEPATOLOGY 2007.)


Gastroenterology | 2010

Natural Killer Cells Are Polarized Toward Cytotoxicity in Chronic Hepatitis C in an Interferon-Alfa-Dependent Manner

Golo Ahlenstiel; Rachel Titerence; Christopher Koh; Birgit Edlich; Jordan J. Feld; Yaron Rotman; Marc G. Ghany; Jay H. Hoofnagle; T. Jake Liang; Theo Heller; Barbara Rehermann

BACKGROUND & AIMS Patients with chronic hepatitis C virus (HCV) infection display great variability in disease activity and progression. Although virus-specific adaptive immune responses have been characterized extensively and found to be impaired in chronic hepatitis C, the role of innate immune responses in disease activity and progression of chronic hepatitis C is not well understood. METHODS We studied 42 HCV-infected patients and 12 healthy uninfected controls. RESULTS We found an increased frequency of natural killer (NK) cells expressing tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), NKp44, NKG2C, and CD122 in chronic hepatitis C as compared with healthy controls (P < .05 for all markers) and stronger activation of NK cells in the liver than in the blood (P < .05). This NK cell phenotype was associated with polarization of NK cell function toward CD107a expression as a marker of degranulation, but with not increased interferon (IFN)-gamma production of CD56(dim) NK cells. The polarized NK cell phenotype correlated with alanine aminotransferase levels (r(2) = 0.312, P = .03). To investigate whether in vivo exposure of NK cells to HCV-induced type I IFN was causing this NK cell phenotype, peripheral blood mononuclear cells from 10 healthy controls and 8 HCV-infected patients were stimulated in the presence of IFN-alfa, which resulted in increased NK cell expression of TRAIL and CD107a (P < .001), but not IFN-gamma. CONCLUSIONS Collectively, these results describe a polarized NK cell phenotype induced by chronic exposure to HCV-induced IFN-alfa. This phenotype may contribute to liver injury through TRAIL expression and cytotoxicity, whereas the lacking increase in IFN-gamma production may facilitate the inability to clear HCV.


Gastroenterology | 2011

Host response to translocated microbial products predicts outcomes of patients with HBV or HCV infection

Netanya G. Sandler; Christopher Koh; Annelys Roque; Jason L. Eccleston; Rebecca B. Siegel; Mary DeMino; David E. Kleiner; Steven G. Deeks; T. Jake Liang; Theo Heller

BACKGROUND & AIMS Chronic infection with hepatitis B or C virus (HBV or HCV) is a leading cause of cirrhosis by unknown mechanisms of pathogenesis. Translocation of gut microbial products into the systemic circulation might increase because of increased intestinal permeability, bacterial overgrowth, or impaired clearance of microbial products by Kupffer cells. We investigated whether the extent and progression of liver disease in patients with chronic HBV or HCV infection are associated with microbial translocation and subsequent activation of monocytes. METHODS In a retrospective study, we analyzed data from 16 patients with minimal fibrosis, 68 with cirrhosis, and 67 uninfected volunteers. We analyzed plasma levels of soluble CD14 (sCD14), intestinal fatty acid binding protein, and interleukin-6 by enzyme-linked immunosorbent assay, and lipopolysaccharide (LPS) by the limulus amebocyte lysate assay, at presentation and after antiviral treatment. RESULTS Compared with uninfected individuals, HCV- and HBV-infected individuals had higher plasma levels of LPS, intestinal fatty acid binding protein (indicating enterocyte death), sCD14 (produced upon LPS activation of monocytes), and interleukin-6. Portal hypertension, indicated by low platelet counts, was associated with enterocyte death (P=.045 at presentation, P<.0001 after therapy). Levels of sCD14 correlated with markers of hepatic inflammation (P=.02 for aspartate aminotransferase, P=.002 for ferritin) and fibrosis (P<.0001 for γ-glutamyl transpeptidase, P=.01 for alkaline phosphatase, P<.0001 for α-fetoprotein). Compared to subjects with minimal fibrosis, subjects with severe fibrosis at presentation had higher plasma levels of sCD14 (P=.01) and more hepatic CD14+ cells (P=.0002); each increased risk for disease progression (P=.0009 and P=.005, respectively). CONCLUSIONS LPS-induced local and systemic inflammation is associated with cirrhosis and predicts progression to end-stage liver disease in patients with HBV or HCV infection.


Hepatology | 2006

Nodular regenerative hyperplasia : Not all nodules are created equal

Preeti A. Reshamwala; David E. Kleiner; Theo Heller

Nodular regenerative hyperplasia (NRH) of the liver is an uncommon condition characterized by the diffuse transformation of normal hepatic parenchyma into small, regenerative nodules with little to no fibrosis. A classification system proposed by Wanless in 19901 provided histological criteria for the diagnosis of NRH. These included the presence of hepatocellular nodules less than 3 mm in diameter that were not surrounded by fibrosis (nodules graded 0-3 based on the extent of nodularity noted through all fields of the biopsy), and the presence of fibrous septa (graded 0-3). Biopsy specimens that met the criteria of 3 nodularity and 0-1 fibrous septa were classified as nodular regenerative hyperplasia. NRH has been reported to occur in association with other systemic diseases, including rheumatologic disorders, vascular disorders, and myeloproliferative disorders, as well as certain drugs.1-10 Nodular regenerative hyperplasia may have a prolonged asymptomatic course unless it is complicated by portal hypertension and its sequelae, including variceal bleeding, ascites, and splenomegaly. In this article, the epidemiology, histology, differential diagnosis, and theories of etiology of NRH are reviewed. The diagnosis and treatment of nodular regenerative hyperplasia are also presented.


Hepatology | 2004

Effects of antiviral therapy on the cellular immune response in acute hepatitis C

Fareed Rahman; Theo Heller; Yuji Sobao; Eishiro Mizukoshi; Michelina Nascimbeni; Harvey J. Alter; Steven K. Herrine; Jay H. Hoofnagle; T. Jake Liang; Barbara Rehermann

Spontaneous recovery occurs in a minority of patients with acute hepatitis C but is associated with vigorous and long‐lasting cellular immune responses. Treatment‐induced recovery can be achieved in the majority of patients who are treated in the acute phase, but the kinetics and mechanisms of viral clearance and immune responsiveness are not known. Both direct antiviral effects and indirect immune‐mediated effects, such as immune modulation of Th2 to Th1 responses and prevention of exhaustion of cellular responses by rapid reduction of viral titer, have been proposed. To investigate how early antiviral therapy affects hepatitis C virus (HCV)‐specific T cell responses, we performed detailed prospective clinical, virological, and immunological studies on 7 patients with acute hepatitis C who received antiviral therapy and were followed at 2 to 4 week intervals for 1 to 2 years. The total CD4+ and CD8+ cell response was analyzed with 600 overlapping HCV peptides and 6 proteins by ex vivo enzyme‐linked immunospot (ELISpot), intracellular cytokine staining, and proliferation assays. In contrast to earlier studies with selected HCV epitopes, this extended analysis detected multispecific interferon γ+ (IFN‐γ+) responses in each patient, even in the absence of T‐cell proliferation. After initiation of antiviral therapy (at a mean of 20 weeks after infection), all sustained responders demonstrated gradually decreasing, then nearly absent HCV‐specific T‐cell responses, whereas the sole patient who developed viral breakthrough after initial HCV control maintained cellular immune responses. In conclusion, a sustained response to antiviral therapy was not associated with a lasting enhancement of HCV‐specific T‐cell responsiveness in the blood. (HEPATOLOGY 2004;40:87–97.)


Journal of Virology | 2002

Interaction of Hepatitis C Virus-Like Particles and Cells: a Model System for Studying Viral Binding and Entry

Miriam Triyatni; Bertrand Saunier; Padma Maruvada; Anthony R. Davis; Luca Ulianich; Theo Heller; Arvind H. Patel; Leonard D. Kohn; T. Jake Liang

ABSTRACT Hepatitis C virus-like particles (HCV-LPs) containing the structural proteins of HCV H77 strain (1a genotype) was used as a model for HCV virion to study virus-cell interaction. HCV-LPs showed a buoyant density of 1.17 to 1.22 g/cm3 in a sucrose gradient and formed double-shelled particles 35 to 49 nm in diameter. Flow cytometry analysis by an indirect method (detection with anti-E2 antibody) and a direct method (use of dye-labeled HCV-LPs) showed that HCV-LPs binds to several human hepatic (primary hepatocytes, HepG2, HuH7, and NKNT-3) and T-cell (Molt-4) lines. HCV-LPs binding to cells occurred in a dose- and calcium-dependent manner and was not mediated by CD81. Scatchard plot analysis suggests the presence of two binding sites for HCV-LPs with high (Kd ∼1 μg/ml) and low (Kd ∼50 to 60 μg/ml) affinities of binding. Anti-E1 and -E2 antibodies inhibited HCV-LPs binding to cells. While preincubation of HCV-LPs with very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), or high-density lipoprotein (HDL) blocked its binding to cells, preincubation of cells with VLDL, LDL, HDL, or anti-LDL-R antibody did not. Confocal microscopy analysis showed that, after binding to cells, dye-labeled HCV-LPs were internalized into the cytoplasm. This process could be inhibited with anti-E1 or anti-E2 antibodies, suggesting that E1 and E2 proteins mediate HCV-LPs binding and, subsequently, their entry into cells. Altogether, our results indicate that HCV-LPs can be used to further characterize the mechanisms involved in the early steps of HCV infection.


Journal of Virology | 2007

Production of Infectious Hepatitis C Virus of Various Genotypes in Cell Cultures

Takanobu Kato; Takuya Matsumura; Theo Heller; Satoru Saito; Ronda K. Sapp; Krishna K. Murthy; Takaji Wakita; T. Jake Liang

ABSTRACT A unique hepatitis C virus (HCV) strain JFH-1 has been shown to replicate efficiently in cell culture with production of infectious HCV. We previously developed a DNA expression system containing HCV cDNA flanked by two self-cleaving ribozymes to generate HCV particles in cell culture. In this study, we produced HCV particles of various genotypes, including 1a (H77), 1b (CG1b), and 2a (J6 and JFH-1), in the HCV-ribozyme system. The constructs also contain the secreted alkaline phosphatase gene to control for transfection efficiency and the effects of culture conditions. After transfection into the Huh7-derived cell line Huh7.5.1, continuous HCV replication and secretion were confirmed by the detection of HCV RNA and core antigen in the culture medium. HCV replication levels of strains H77, CG1b, and J6 were comparable, whereas the JFH-1 strain replicates at a substantially higher level than the other strains. To evaluate the infectivity in vitro, the culture medium of JFH-1-transfected cells was inoculated into naive Huh7.5.1 cells. HCV proteins were detected by immunofluorescence 3 days after inoculation. To evaluate the infectivity in vivo, the culture medium from HCV genotype 1b-transfected cells was inoculated into a chimpanzee and caused a typical course of HCV infection. The HCV 1b propagated in vitro and in vivo had sequences identical to those of the HCV genomic cDNA used for cell culture transfection. The development of culture systems for production of various HCV genotypes provides a valuable tool not only to study the replication and pathogenesis of HCV but also to screen for antivirals.

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Christopher Koh

National Institutes of Health

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David E. Kleiner

National Institutes of Health

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Jay H. Hoofnagle

National Institutes of Health

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Steven M. Holland

National Institutes of Health

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Marc G. Ghany

National Institutes of Health

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Xiongce Zhao

National Institutes of Health

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Harry L. Malech

National Institutes of Health

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Yaron Rotman

National Institutes of Health

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William A. Gahl

National Institutes of Health

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