PubMed HealthSearch

Biomedical subjects

Paul Klenerman

Publications and source records attributed to Paul Klenerman.

4 recordsLinked to original sources

PRMT5-mediated intron retention triggers innate and adaptive immunity against cancer.

PRMT5 is expressed at high levels in many cancers, where it regulates diverse cellular pathways that contribute to oncogenesis. Here, we have defined a new role for PRMT5 in regulating and coordinating the interplay between the innate and adaptive immune response. This occurs, in part, through the influence of PRMT5 and E2F1 on RNA splicing and the presence of retained introns (RIs). We found that RIs have a propensity to form double-stranded RNAs that contribute to the innate response. Furthermore, many RIs contain non-canonical open-reading frames (ncORFs), which can be translated and then processed into small peptides that assemble with the MHC class I complex. Significantly, RI-derived peptides are highly immunogenic and, as a murine cancer vaccine, carrying a string of antigenic RI peptides, delayed tumour growth and enhanced survival. RIs are present in human tumour cells, and we identified T lymphocytes in human cancer patients, with antigen specificity for RI-derived peptides, that killed human tumour cells in vitro. Regulating intron retention thus offers a new therapeutic approach to enhance tumour immunogenicity.

Animals

Guidelines for T cell nomenclature.

Advances in T cell biology have revealed heterogeneity among T cell populations that is not captured by existing general nomenclature. This issue has caused an ad hoc broadening of core T cell subset definitions and the invention of new subset designations that have not been uniformly delineated. To address this issue, in this Consensus Statement, we propose guidelines that serve three goals. First, they advocate that primary research reports define the experimental basis by which relevant subsets are designated in the methods section of each study. Second, they provide standardized definitions for existing subset designations in popular use, and common experimental criteria for defining each subset are noted. Last, they present an alternative 'modular nomenclature' paradigm. The newly proposed modular nomenclature eschews conceptualization of antigen-experienced T cells as belonging to a few idealized subsets, and the nomenclature instead simply indicates individual biological properties present in a T cell population with brief descriptors. Collectively, these guidelines intend to enhance transparency in the literature while facilitating clearer communication of findings and concepts to researchers, students and clinicians.

Terminology as Topic

Genetically distinct within-host subpopulations of hepatitis C virus persist after Direct-Acting Antiviral treatment failure.

Analysis of viral genetic data has previously revealed distinct within-host population structures in both untreated and interferon-treated chronic hepatitis C virus (HCV) infections. While multiple subpopulations persisted during the infection, each subpopulation was observed only intermittently. However, it was unknown whether similar patterns were also present after Direct-Acting Antiviral (DAA) treatment, where viral populations were often assumed to go through narrow bottlenecks. Here we tested for the maintenance of population structure after DAA treatment failure, and whether there were different evolutionary rates along distinct lineages where they were observed. We analysed whole-genome next-generation sequencing data generated from a randomised study using DAAs (the BOSON study). We focused on samples collected from patients (N=84) who did not achieve sustained virological response (i.e., treatment failure) and had sequenced virus from multiple timepoints. Given the short-read nature of the data, we used a number of methods to identify distinct within-host lineages including tracking concordance in intra-host nucleotide variant (iSNV) frequencies, applying sequenced-based and tree-based clustering algorithms to sliding windows along the genome, and haplotype reconstruction. Distinct viral subpopulations were maintained among a high proportion of individuals post DAA treatment failure. Using maximum likelihood modelling and model comparison, we found an overdispersion of viral evolutionary rates among individuals, and significant differences in evolutionary rates between lineages within individuals. These results suggest the virus is compartmentalised within individuals, with the varying evolutionary rates due to different viral replication rates and/or different selection pressures. We endorse lineage awareness in future analyses of HCV evolution and infections to avoid conflating patterns from distinct lineages, and to recognise the likely existence of unsampled subpopulations.

Humans

Ex vivo phenotype and frequency of influenza virus-specific CD4 memory T cells.

Recent advances in class II tetramer staining technology have allowed reliable direct ex vivo visualization of antigen-specific CD4 T cells. In order to define the frequency and phenotype of a prototype response to a nonpersistent pathogen, we have used such techniques to analyze influenza virus-specific memory CD4 T cells directly from blood. These responses are stably detectable ex vivo at low frequencies (range, 0.00012 to 0.0061% of CD4 T cells) and display a distinct "central memory" CD62L(+) phenotype.

CD4-Positive T-Lymphocytes