Liquid biopsies of circulating tumor cells (CTCs) have the potential to transform cancer management through non-invasive, real-time feedback on patient conditions. However, immunoaffinity-based liquid biopsies typically suffer from low throughput, relative complexity, and postprocessing limitations. Here, we addressed these issues simultaneously by decoupling and independently optimizing the nano-, micro-, and macro-scales of an enrichment device that is simple to fabricate and operate. Unlike other affinity-based devices, our scalable mesh approach enables optimum capture conditions at any flow rate. The device detected CTCs under experimental conditions and in the blood of cancer patients where it also allowed for postprocessing and, thus, identification of clinically relevant biomarkers such as HER2, but also has the potential to predict patient response to therapies such as immune checkpoint inhibition therapy in the future. This suggests that our approach can overcome major limitations associated with affinity-based liquid biopsies and help improve cancer management.

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Bacillus cereus G9241 was isolated from a Louisiana welder suffering from an anthrax-like infection. The organism carries two transcriptional regulators that have previously been proposed to be incompatible with each other in Bacillus anthracis: the pleiotropic transcriptional regulator PlcR found in most members of the Bacillus cereus group but truncated in all B. anthracis isolates, and the anthrax toxin regulator AtxA found in all B. anthracis strains and a few B. cereus sensu stricto strains. Here we report cytotoxic and haemolytic activity of cell free B. cereus G9241 culture supernatants cultured at 25 °C to various eukaryotic cells. However, this is not observed at the mammalian infection relevant temperature 37 °C, behaving much like the supernatants generated by B. anthracis. Using a combination of genetic and proteomic approaches to understand this unique phenotype, we identified several PlcR-regulated toxins to be secreted highly at 25 °C compared to 37 °C. Furthermore, results suggest that differential expression of the protease involved in processing the PlcR quorum sensing activator molecule PapR appears to be the limiting step for the production of PlcR-regulated toxins at 37 °C, giving rise to the temperature-dependent haemolytic and cytotoxic activity of the culture supernatants. This study provides an insight on how B. cereus G9241 is able to ‘switch’ between B. cereus and B. anthracis–like phenotypes in a temperature-dependent manner, potentially accommodating the activities of both PlcR and AtxA.

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Bacillus cereus G9241 was isolated from a welder who survived a pulmonary anthrax-like disease. Strain G9241 carries two virulence plasmids, pBCX01 and pBC210, as well as an extrachromosomal prophage, pBFH_1. pBCX01 has 99.6% sequence identity to pXO1 carried by Bacillus anthracis and encodes the tripartite anthrax toxin genes and atxA, a mammalian virulence transcriptional regulator. This work looks at how the presence of pBCX01 and temperature may affect the lifestyle of B. cereus G9241 using a transcriptomic analysis and by studying spore formation, an important part of the B. anthracis lifecycle. . Here we report that pBCX01 has a stronger effect on gene transcription at the mammalian infection relevant temperature of 37˚C in comparison to 25˚C. At 37˚C, the presence of pBCX01 appears to have a negative effect on genes involved in cell metabolism, including biosynthesis of amino acids, whilst positively affecting the transcription of many transmembrane proteins. The figure below shows the first image of the anthrax G9241 cross-over strain linear chromosome bacteriophage (unusual in bacteriophage itself).

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We reveal that the developing Drosophila nerve cord has a distinctive architectural structure, which is driven by JNK signalling.
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A collaborative study by the Thompson group with Dr Robin Thompson's (Mathematics Institute, University of Warwick) and Dr Uri Obolski's (Tel Aviv University) groups. The study examines the impact of prior immunity conferred by SARS-CoV-2 or seasonal coronavirus infection on the emergence of new variants using mathematical modelling . We find that, if cross-reactive immunity is complete (i.e. someone infected by the previously circulating virus is not susceptible to the novel variant), the novel variant must be more transmissible than the previous virus to invade the population. However, in a more realistic scenario in which cross-reactive immunity is partial, we show that it is possible for novel variants to invade, even if they are less transmissible than previously circulating viruses. Finally, we find that if previous infection with the antigenically related virus assists the establishment of infection with the novel variant, as has been proposed following some experimental studies, then even variants with very limited transmissibility are able to invade the host population.

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The GibsonGroup have a programme of research to investigate how glycans (sugars) can be used in biosensing or diagnosis of disease. In the latest publication from the team, they show how otherwise identifical proteins with different glycosylation patterns can be identified and discriminated between. This is achieved by using antibodies immobilised on biolayer interferometry sensors which can first target all glycoforms (and hence are are not specific). In a second step, gold nanoparticles labelled with lectins (carbohydrate binding proteins) are used to identify which glycoform is present, and due to the large mass of the gold particles leads to signal enhancement. This is demonstrated for prostate specific antigen - a key biomarker for prostate diseases including cancer. It is known that the glycosylation pattern, not just protein concentration, is a hallmark of disease state but current techniques do not distinguish glycoforms. The method shown her can be automated and takes < 90 minutes to complete in this proof of concept study.
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3-D tissue models (such as spheroids and organoids) better predict physiological responses than 2D monolayers and may play a role in reducing animal usage, particularly in toxicology. Spheroids are more challenging, however, to work with than cell monolayers and hence there is a barrier to their use. Spheroids can also not (always) be easily cryopreserved and hence buying them ‘off the shelf’ and ‘ready to use’ is not common or is expensive. The GibsonGroup, working with Cryologyx, have show in this latest work that their macromolecular cryoprotectants can protect live cell spheroids during cryopreservation allowing the recovery of viable spheroids direct from the freezer.
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Sleep and circadian rhythm disruption (SCRD), as encountered during shift work, increases the risk of respiratory viral infection including SARS-CoV-2. However, the mechanism(s) underpinning higher rates of respiratory viral infection following SCRD remain poorly characterised. To address this, we investigated the effects of acute sleep deprivation on the mouse lung transcriptome. Here we show that sleep deprivation profoundly alters the transcriptional landscape of the lung, causing the suppression of both innate and adaptive immune systems, disrupting the circadian clock, and activating genes implicated in SARS-CoV-2 replication, thereby generating a lung environment that promotes viral infection and associated disease pathogenesis. Our study provides a mechanistic explanation of how SCRD increases the risk of respiratory viral infections including SARS-CoV-2 and highlights therapeutic avenues for the prevention and treatment of COVID-19.
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Nuria Ferrandiz and colleagues in the Royle lab published a paper in J Cell Biol this summer on mitotic chromosome "ensheathing" by endomembranes. This paper was selected by the JCB as one of the 10 best papers of 2022. JCB have put together a supplement containing summaries of all ten papers with photos of the authors.
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The GibsonGroup have a large interest in mimicking the function of ice binding proteins (IBPs) using polymers, which have huge biotechnological, biomedical and industrial potential. The team have previously made progress in mimicking ‘antifreeze’ proteins, but the search for a polymer which can nucleate ice has been elusive. Ice nucleating proteins (INPs) are very large, and truncated versions are far less active, and the native proteins are immobilised in membranes making their study challenging. In this latest work, the team report (what they believe) is the first polymeric ice nucleator. To achieve this they took an ice binding polymer and used synthetic polymer chemistry to make a ‘brush shaped’ polymer to introduce rigidity and very high molecular weight (100’s of kDAs). This new tool is the first synthetically accessible ‘organic’ probe for ice nucleation.
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Congratulations to Dr Cerys Currie, winner of the Science Category in the Women of the Future Awards. She received her award at a ceremony in London on Wednesday 9 November. Two members of Warwick Medical School were shortlisted this year. Alongside Cerys, Postdoctoral Research Fellow and final year medical student Ramat Ayoola, was nominated in the Community Spirit category.

Association between fetal abdominal growth trajectories, maternal metabolite signatures early in pregnancy, and childhood growth and adiposity: prospective observational multinational INTERBIO-21st fetal study

New study from the Bowman Lab published in eLife defines a novel nuclear translocation pathway involving the specific import receptor Importin-5 and the histone chaperone NASP that specialise in ferrying monomeric histones to the nucleus.

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Nanoparticles have found widespread use in diagnostics and have been suggested for e.g. drug delivery. Chemists can now fine tune the nanoparticle surface to e.g target cell types. However, what a cell 'sees' is not what is made by the chemists, but rather a complex mixture of proteins which ‘foul’ the surface, recruited from the blood, termed the protein corona. There has been extensive research into the proteins which make up the corona, but the glycans on these proteins have received less attention. This is a major problem, as > 50 % of our proteome is glycosylated, and hence investigating a nanoparticle’s protein corona, without considering the glycans, does not give an accurate picture.

In our latest work, we investigate the impact of the glycoprotein corona on how polymer-coated nanoparticles bind lectins. We show that serum proteins bring significant sialic acids to the particle surface. The impact of this, is that the particles can bind additional lectins (which were not intended) as well as those which are intended. Finally, we show that 'blocking' the surface does reduce the amount of protein, but sufficient glycans remain to cause off-target binding. These results will help guide the next generation of nanoparticle sensing and delivery agents.
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The use of nanoparticles as drug delivery vehicles is well established. Numerous studies have investigated the impact of size, shape, charge, and surface functionality of nanoparticles on mammalian cellular uptake. Rigidity, however, has been studied to a far lesser extent, and its effects are still unclear. Here, in a collaboration between the Chemistry and BMS, this is systematically explored.

Three different polymeric core rigidities were tested: hard, medium and soft using two 50 and 100 nm diameter particles. Cellular uptake studies indicated that 100nm softer particles are taken up faster and 3-fold more into mammalian cells compared to harder nanoparticles, probably via major differences in the cellular uptake pathways. However, 50 nm derivatives did not show any appreciable differences in uptake efficiency suggesting that rigidity as a parameter for nanomaterials in the biological regime might be size dependent.

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In a recent study published in Cell Reports, teams from University College London and Warwick Medical School describe how protein fusion of two epigenetic modulators, JAZF1 and SUZ12, causes oncogenesis in human endometrial stromal cells by disrupting the composition of the polycomb repressive complex 2 (PRC2), resulting in aberrant histone modification, gene expression and cell differentiation (decidualization). The results reveal how dysregulation of PRC2 drives the emergence of low-grade endometrial stromal sarcomas in the womb, which provide opportunities to improve the treatment of this disease.

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Much cell biology, biomaterials and associated research is conducted on cells attached to tissue culture plastic in multiwell plates - such as high throughput drug discovery and toxicity, to viral plaque assays. However, there is a disconnect that the cells are stored frozen in suspension, not in the format ‘ready to use’. This is because conventional cryoprotectants do not protect the cells when in monolayer format. The GibsonGroup, and UoW Spin-Out Cryologyx have worked together to solve this problem using macromolecular cryoprotectants. In this later paper, the team demonstrate reproducilble and robust recovery of cell monolayers out of the freezer. This is shown for common cell lines, including HepG2 and Caco-2, commonly used in drug screening. This is a revolutionary technology as it shows researchers could stop wasting time culturing cells, and just order them, remove from freezer and within 24 hours begin data collection with no of the traditional culturing steps. Cryologyx are deploying these findings to commercialise assay ready cells, and trial plates are available!

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A new technique for freezing cells for use in biomedical research, based on polymer technology developed at the University of Warwick, has been validated in study, paving the way for faster results for scientists in their research.

All cells must accurately separate their chromosomes during mitosis to avoid errors that are associated with cancer development, reproductive failure and even ageing. This feat is accomplished by the mitotic spindle – this microtubule-based machine has a bipolar geometry and contains hundreds of protein components. A subset of microtubules form bundles that make contact with kinetochores on the chromosome (these are called K-fibres). The growth and shrinkage of these microtubules, through addition and loss of tubulin, is coupled to the hydrolysis of GTP: this powers chromosome movement. Previous work identified a protein called HURP (hepatoma up-regulated protein) that forms distinctive stripes on each half spindle (see schematic). Here, through collaboration with University of Geneva, we identified a new region within the mitotic spindle, termed “HURP-gap”. This HURP free region of the K-fibre is located between the stripe and the kinetochore.

Discovery: How do organs reach a specific size during development? The Hippo/YAP pathway has been identified as a critical regulator of organ size control. It also plays an important role in homeostasis and cancer progression, in part due to its mechanosensitive response. Here, the Saunders lab have developed an optogenetic version of YAP (optoYAP) that enables its localisation to the nucleus to be tightly controlled in both space and time. This enables targeted perturbation of the pathway, with potential applications to wound healing and regeneration.
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The GibsonGroup are developing macromolecular (polymer) cryoprotectants to enable next-generation cell based therapies, and to simplify cell-based assays. A key feature identified in the teams most potent materials is a mixture of cationic/anionic charges on the side chain, but the exact mechanism of action is under investigation. In this latest work the team explored sulphoxide (‘DMSO like’) side chains, which are actually highly polarised with S+-O- character. The team also explore N-oxide polymers which have similar charged character. Using a range of phyical and biochemical assays the team investigated if these motifs could aid in cryopreservation.
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We have now published back to back two papers on the so called anthrax “cross over strain Bacillus cereus G9241. The first paper (From cereus to anthrax and back again: The role of the PlcR regulator in the “cross-over” strain Bacillus cereus G9241) has already been highlighted. This current paper is titled, “The influence of extrachromosomal elements in the anthrax “cross-over” strain Bacillus cereus G9241.”

The work investigates the contribution of anthrax-like plasmids and a lysogenic phagemid to the pathogenic potential of the normally relatively harmless Bacillus cereus. We investigated the role of temperature and carriage of the pBCXO1 plasmid (which is homologous to the pXO1 anthrax toxin plasmid) in regulation of chromosomal genes, heavily affecting metabolism. In addition we have shown that sporulation of G9241 is very rapid at 37’C, which is characteristic of B. anthracis but unlike the ancestral B. cereus strains. Finally we isolated phagemid virions which are produced at 37’C and visualised them with electron microscopy.

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In our recent paper “From cereus to anthrax and back again: The role of the PlcR regulator in the “cross-over” strain Bacillus cereus G9241” we have investigated how a normally low risk Bacillus cereus strain has evolved to mimic Bacillus anthracis, the causative agent of the highly feared lethal anthrax infection. The B. cereus G9241 strain is one of several relatively recent isolates that are termed “anthrax cross over strains” that intriguingly seem to preferentially infect metal workers in the USA (welders / millers). These strains are of particular concern as, unlike B. anthracis proper, they can switch between a form that can survive and replicate in the environment using invertebrate hosts and the more lethal mammalian infective anthrax like form. B. anthracis must pass from mammalian host to mammalian host as a spore form thus somewhat limiting its spread. This is due to a loss of function mutation in a key regulator protein named PlcR, which in all other B. cereus sensu lato group strains allows for survival outside of a mammalian host. Our work has identified the specific mechanism by which G9241 can switch on and off the PlcR regulation endowing it with a “Dr. Jekyll or Mr. Hyde” like life cycle. This work was a culmination of a Marie Curie fellow, 3 PhD students and one postdoc and was supported by MoD Porton Down DSTL funding and advice, for which we are very grateful.

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One of the key questions relating to the COVID-19 pandemic is how prior immunity to related endemic coronaviruses affects the SARS-CoV-2 immune response. In this study, we provide evidence of immunological imprinting in individuals with fatal outcomes from COVID-19, suggesting an antibody profile consistent with an original antigenic sin type-response. Read the paper hereLink opens in a new window.

Cansu Küey’s PhD work was published this week in eLife. Together with Méghane, Gabrielle and Miguel, she showed that clathrin-coated pits can be made to form on intracellular membranes. This phenomenon allowed us to redefine two key concepts in clathrin-coated vesicle formation. First, a scission molecule is not needed to pinch off vesicles inside the cell. Second, that most of the other proteins found in regular clathrin coats are not essential for vesicle formation.