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Biology subjects

Britton, E.

Publications and source records attributed to Britton, E..

4 recordsLinked to original sources

Identification of leptospiral protein antigens recognized by WC1+ γδ T cell subsets as target for development of recombinant vaccines

Pathogenic Leptospira species cause leptospirosis, a neglected zoonotic disease recognized as a global public health problem. It is also the cause of the most common cattle infection that results in major economic losses due to reproductive problems. {gamma}{delta} T cells play a role in the protective immune response in livestock species against Leptospira while human {gamma}{delta} T cells also respond to Leptospira. Thus, activation of {gamma}{delta} T cells has emerged as a potential component for optimization of vaccine strategies. Bovine {gamma}{delta} T cells proliferate and produce IFN-{gamma} in response to vaccination with inactivated leptospires and this response is mediated by a specific subpopulation of the WC1-bearing {gamma}{delta} T cells. WC1 molecules are members of the group B scavenger receptor cysteine rich (SRCR) superfamily and are composed of multiple SRCR domains, of which particular extracellular domains act as ligands for Leptospira. Since WC1 molecules function as both pattern recognition receptors and {gamma}{delta} TCR coreceptors, the WC1 system has been proposed as a novel target to engage {gamma}{delta} T cells. Here, we demonstrate the involvement of leptospiral protein antigens in the activation of WC1+ {gamma}{delta} T cells and identified two leptospiral outer membrane proteins able to interact directly with them. Interestingly, we show that the protein-specific {gamma}{delta} T cell response is composed of WC1.1+ and WC1.2+ subsets, although a greater number of WC1.1+{gamma}{delta} T cells respond. Identification of protein antigens will enhance our understanding of the role {gamma}{delta} T cells play in the leptospiral immune response and in recombinant vaccine development.

immunology↗

Repurposing of KLF5 activates a cell cycle signature during the progression from Barrett's oesophagus to oesophageal adenocarcinoma.

Oesophageal adenocarcinoma (OAC) is one of the most common causes of cancer deaths and yet compared to other common cancers, we know relatively little about the underlying molecular mechanisms. Barretts oesophagus (BO) is the only known precancerous precursor to OAC, but our understanding about the specific events leading to OAC development is limited. Here, we have integrated gene expression and chromatin accessibility profiles of human biopsies of BO and OAC and identified a strong cell cycle gene expression signature in OAC compared to BO. Through analysing associated chromatin accessibility changes, we have implicated the transcription factor KLF5 in the transition from BO to OAC. Importantly, we show that KLF5 expression is unchanged during this transition, but instead, KLF5 is redistributed across chromatin in OAC cells to directly regulate cell cycle genes specifically in OAC. Our findings have potential prognostic significance as the survival of patients with high expression of KLF5 target genes is significantly lower. We have provided new insights into the gene expression networks in OAC and the mechanisms behind progression to OAC, chiefly the repurposing of KLF5 for novel regulatory activity in OAC.

cancer biology↗

Identification of a primitive intestinal transcription factor network shared between oesophageal adenocarcinoma and its pre-cancerous precursor state.

Oesophageal adenocarcinoma (OAC) is one of the most frequent causes of cancer deaths and yet compared to other common cancers, we know relatively little about the molecular composition of this tumour type. To further our understanding of this cancer we have used open chromatin profiling to decipher the transcriptional regulatory networks that are operational in OAC. We have uncovered a transcription factor network that is usually found in primitive intestinal cells during embryonic development, centred on HNF4A and GATA6. These transcription factors work together to control the OAC transcriptome. Importantly, we show that this network is activated in Barretts oesophagus, the putative precursor state to OAC thereby providing novel molecular evidence in support of stepwise malignant transition. Furthermore, we show that HNF4A alone, is sufficient to drive chromatin opening and activation of a Barretts-like chromatin signature when expressed in normal human epithelial cells. Collectively, these data provide a new way to categorise OAC at a genome scale and implicate HNF4A activation as a potential pivotal event in regulating its malignant transition from healthy cells.

cancer biology↗

Metagenomic next-generation sequencing reveals Miamiensis avidus (Ciliophora: Scuticociliatida) in the 2017 epizootic of leopard sharks (Triakis semifasciata) in San Francisco Bay, California

During March to August of 2017, hundreds of leopard sharks (Triakis semifasciata) stranded and died on the shores of San Francisco Bay, California, USA. Similar mass stranding events occurred in 1967 and 2011, yet analysis of these epizootics was incomplete and no etiology was confirmed. Our investigation of the most recent epizootic revealed severe meningoencephalitis in stranded sharks, raising suspicion for infection. On this basis, we pursued a strategy for unbiased pathogen detection using metagenomic next-generation sequencing followed by orthogonal validation and further screening. We show that the ciliated protozoan pathogen, Miamiensis avidus, was present in the central nervous system of leopard (n=12) and other shark species (n=2) that stranded in San Francisco Bay, but absent in leopard sharks caught elsewhere. Whereas this protozoan has previously been implicated in devastating outbreaks in teleost marine fish, our findings represent the first report of a ciliated protozoan infection in wild elasmobranchs. This discovery highlights the benefits of adopting unbiased metagenomic sequencing in the study of wildlife health and disease.

microbiology↗