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1.
Wellcome Open Res ; 6: 93, 2021.
Article in English | MEDLINE | ID: mdl-34405118

ABSTRACT

Background: The world health organization (WHO) has identified the need for a better understanding of which patients with hepatitis C virus (HCV) can be cured with ultrashort course HCV therapy. Methods: A total of 202 individuals with chronic HCV were randomised to fixed-duration shortened therapy (8 weeks) vs variable-duration ultrashort strategies (VUS1/2). Participants not cured following first-line treatment were retreated with 12 weeks' sofosbuvir/ledipasvir/ribavirin. The primary outcome was sustained virological response 12 weeks (SVR12) after first-line treatment and retreatment. Participants were factorially randomised to receive ribavirin with first-line treatment. Results: All evaluable participants achieved SVR12 overall (197/197, 100% [95% CI 98-100]) demonstrating non-inferiority between fixed-duration and variable-duration strategies (difference 0% [95% CI -3.8%, +3.7%], 4% pre-specified non-inferiority margin). First-line SVR12 was 91% [86%-97%] (92/101) for fixed-duration vs 48% [39%-57%] (47/98) for variable-duration, but was significantly higher for VUS2 (72% [56%-87%] (23/32)) than VUS1 (36% [25%-48%] (24/66)). Overall, first-line SVR12 was 72% [65%-78%] (70/101) without ribavirin and 68% [61%-76%] (69/98) with ribavirin (p=0.48). At treatment failure, the emergence of viral resistance was lower with ribavirin (12% [2%-30%] (3/26)) than without (38% [21%-58%] (11/29), p=0.01). Conclusions: Unsuccessful first-line short-course therapy did not compromise retreatment with sofosbuvir/ledipasvir/ribavirin (100% SVR12). SVR12 rates were significantly increased when ultrashort treatment varied between 4-7 weeks rather than 4-6 weeks. Ribavirin significantly reduced resistance emergence in those failing first-line therapy. ISRCTN Registration: 37915093 (11/04/2016).

2.
BMC Public Health ; 19(1): 829, 2019 Jun 26.
Article in English | MEDLINE | ID: mdl-31242901

ABSTRACT

BACKGROUND: International sustainable development goals for the elimination of viral hepatitis as a public health problem by 2030 highlight the need to optimize strategies for prevention, diagnosis and treatment of hepatitis B virus (HBV) infection. An important priority for Africa is to have affordable, accessible and sustainable prevention of mother to child transmission (PMTCT) programmes, delivering screening and treatment for antenatal women and implementing timely administration of HBV vaccine for their babies. METHODS: We developed a decision-analytic model simulating 10,000 singleton pregnancies to assess the cost-effectiveness of three possible strategies for deployment of tenofovir in pregnancy, in combination with routine infant vaccination: S1: no screening nor antiviral therapy; S2: screening and antiviral prophylaxis for all women who test HBsAg-positive; S3: screening for HBsAg, followed by HBeAg testing and antiviral prophylaxis for women who are HBsAg-positive and HBeAg-positive. Our outcome was cost per infant HBV infection avoided and the analysis followed a healthcare perspective. RESULTS: Based on 10,000 pregnancies, S1 predicts 45 infants would be HBV-infected at six months of age, compared to 21 and 28 infants in S2 and S3, respectively. Relative to S1, S2 had an incremental cost of $3940 per infection avoided. S3 led to more infections and higher costs. CONCLUSION: Given the long-term health burden for individuals and economic burden for society associated with chronic HBV infection, screening pregnant women and providing tenofovir for all who test HBsAg+ may be a cost-effective strategy for South Africa and other low/middle income settings.


Subject(s)
Antiviral Agents/therapeutic use , Cost-Benefit Analysis , Hepatitis B virus/immunology , Hepatitis B/drug therapy , Infectious Disease Transmission, Vertical/prevention & control , Pregnancy Complications, Infectious/drug therapy , Tenofovir/therapeutic use , Adult , Child , Developing Countries , Female , Hepatitis B/blood , Hepatitis B/diagnosis , Hepatitis B/virology , Hepatitis B Surface Antigens/blood , Hepatitis B Vaccines/administration & dosage , Hepatitis B e Antigens/blood , Hepatitis B, Chronic/blood , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/virology , Humans , Infant , Mass Screening , Models, Biological , Pregnancy , Pregnancy Complications, Infectious/blood , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/virology , South Africa , Tenofovir/economics , Vaccination , Young Adult
3.
Nucleic Acids Res ; 45(16): e148, 2017 Sep 19.
Article in English | MEDLINE | ID: mdl-28934479

ABSTRACT

The T cell compartment must contain diversity in both T cell receptor (TCR) repertoire and cell state to provide effective immunity against pathogens. However, it remains unclear how differences in the TCR contribute to heterogeneity in T cell state. Single cell RNA-sequencing (scRNA-seq) can allow simultaneous measurement of TCR sequence and global transcriptional profile from single cells. However, current methods for TCR inference from scRNA-seq are limited in their sensitivity and require long sequencing reads, thus increasing the cost and decreasing the number of cells that can be feasibly analyzed. Here we present TRAPeS, a publicly available tool that can efficiently extract TCR sequence information from short-read scRNA-seq libraries. We apply it to investigate heterogeneity in the CD8+ T cell response in humans and mice, and show that it is accurate and more sensitive than existing approaches. Coupling TRAPeS with transcriptome analysis of CD8+ T cells specific for a single epitope from Yellow Fever Virus (YFV), we show that the recently described 'naive-like' memory population have significantly longer CDR3 regions and greater divergence from germline sequence than do effector-memory phenotype cells. This suggests that TCR usage is associated with the differentiation state of the CD8+ T cell response to YFV.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Complementarity Determining Regions/chemistry , Receptors, Antigen, T-Cell/chemistry , Sequence Analysis, RNA/methods , Software , Algorithms , Animals , CD8-Positive T-Lymphocytes/cytology , Cell Differentiation , Female , Gene Expression Profiling , Humans , Male , Mice, Inbred C57BL , Middle Aged , Receptors, Antigen, T-Cell/metabolism , Single-Cell Analysis , Yellow fever virus/immunology
4.
Science ; 357(6347): 129-130, 2017 07 14.
Article in English | MEDLINE | ID: mdl-28706025
5.
Front Immunol ; 3: 346, 2012.
Article in English | MEDLINE | ID: mdl-23181064

ABSTRACT

Hepatitis C virus infection is a major cause of chronic liver disease. CD4(+) T cells play a key role in disease outcome. However, the critical functions and associated phenotypes of intrahepatic CD4(+) T cells are not well defined. We have previously shown that CD8(+) T cells expressing the C type lectin CD161 are highly enriched in the human liver, especially during chronic hepatitis. These cells are associated with a type 17 differentiation pattern and express cytokines including IL-17A, IL-22, and IFN-γ. We therefore analyzed expression of CD161 on CD4(+) T cells in blood and liver and addressed the relevant phenotype and functional capacity of these populations. We observed marked enrichment of CD161(+)CD4(+) T cells in the liver during chronic hepatitis such that they are the dominant subtype (mean 55% of CD4(+) T cells). IL-22 and IL-17 secreting CD4(+) T cells were readily found in the livers of HCV(+) and NASH donors, although not enriched compared to blood. There was, however, specific enrichment of a novel subset of IL-22/IFN-γ dual secretors (p = 0.02) compared to blood, a result reconfirmed with direct ex vivo analyses. These data indicate the dominance of CD161(+) expressing lymphocyte populations within the hepatic infiltrate, associated with a distinct cytokine profile. Given their documented roles as antiviral and hepatoprotective cytokines respectively, the impact of co-secretion of IFN-γ and IL-22 in the liver may be particularly significant.

6.
Proc Natl Acad Sci U S A ; 107(7): 3006-11, 2010 Feb 16.
Article in English | MEDLINE | ID: mdl-20133607

ABSTRACT

CD8(+) T lymphocytes play a key role in host defense, in particular against important persistent viruses, although the critical functional properties of such cells in tissue are not fully defined. We have previously observed that CD8(+) T cells specific for tissue-localized viruses such as hepatitis C virus express high levels of the C-type lectin CD161. To explore the significance of this, we examined CD8(+)CD161(+) T cells in healthy donors and those with hepatitis C virus and defined a population of CD8(+) T cells with distinct homing and functional properties. These cells express high levels of CD161 and a pattern of molecules consistent with type 17 differentiation, including cytokines (e.g., IL-17, IL-22), transcription factors (e.g., retinoic acid-related orphan receptor gamma-t, P = 6 x 10(-9); RUNX2, P = 0.004), cytokine receptors (e.g., IL-23R, P = 2 x 10(-7); IL-18 receptor, P = 4 x 10(-6)), and chemokine receptors (e.g., CCR6, P = 3 x 10(-8); CXCR6, P = 3 x 10(-7); CCR2, P = 4 x 10(-7)). CD161(+)CD8(+) T cells were markedly enriched in tissue samples and coexpressed IL-17 with high levels of IFN-gamma and/or IL-22. The levels of polyfunctional cells in tissue was most marked in those with mild disease (P = 0.0006). These data define a T cell lineage that is present already in cord blood and represents as many as one in six circulating CD8(+) T cells in normal humans and a substantial fraction of tissue-infiltrating CD8(+) T cells in chronic inflammation. Such cells play a role in the pathogenesis of chronic hepatitis and arthritis and potentially in other infectious and inflammatory diseases of man.


Subject(s)
CD8-Positive T-Lymphocytes/metabolism , Hepacivirus/immunology , Hepatitis C/immunology , NK Cell Lectin-Like Receptor Subfamily B/metabolism , T-Lymphocyte Subsets/immunology , Alanine Transaminase/metabolism , CD8-Positive T-Lymphocytes/classification , Cell Line , Cytokines/metabolism , Fetal Blood/cytology , Fetal Blood/immunology , Flow Cytometry , Fluorescent Antibody Technique , Humans , Immunophenotyping , Luciferases , Receptors, Cytokine/metabolism , Reverse Transcriptase Polymerase Chain Reaction
7.
Am J Transplant ; 3(4): 432-8, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12694065

ABSTRACT

This study evaluates the predictive value of the blood eosinophil count in the diagnosis of acute cellular rejection, its value as a marker of response to treatment, the diagnostic use in a subgroup of patients with normal transaminases and compares blood eosinophilia in patients with and without hepatitis C virus infection. A consecutive cohort of 101 liver transplant patients, 275 liver biopsies, and blood eosinophils recorded on the day or one day before biopsy were analyzed. An elevated eosinophil count has a positive predictive value for acute cellular rejection of 82%. A normal eosinophil count excludes moderate/severe rejection with a predictive value of 86%. The eosinophil count decreases in 69% of patients following treatment of acute cellular rejection with corticosteroids irrespective of treatment outcome. Acute cellular rejection in the presence of an elevated eosinophil count occurs significantly less often (p = 0.007) in patients with hepatitis C virus. An elevated eosinophil count is a valuable marker of acute cellular rejection. However, blood eosinophil levels should not be used to predict acute cellular rejection following treatment with corticosteroids. Blood eosinophilia, seen less often in patients with hepatitis C virus, may reflect an over-diagnosis of acute cellular rejection in these patients.


Subject(s)
Eosinophilia/complications , Graft Rejection/diagnosis , Liver Transplantation , Adult , Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Biopsy , Cohort Studies , Female , Graft Rejection/complications , Graft Rejection/pathology , Hepatitis C/complications , Hepatitis C/surgery , Humans , Male , Middle Aged , Treatment Outcome
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