Show and Cell

The image shows a human cell that has just divided the DNA (in blue) and soon will split all the other components and generate two identical cells. The red colour shows the Nuclear Membrane that will encapsulate and protect the DNA and in green the machinery that will cleave and separate the new-born sister cells.This process is called Cell division. It is a fundamental process at the basis of our existence. From the single cell at conception, about 37.2 trillion cells are generated to make up an adult human being. Divisions need to occur in an extremely accurate manner to produce cells that are healthy and viable. Defects in cell division are responsible for several human pathologies ranging from Down syndrome to cancer. Our research aims to understand how cell division occurs faithfully and how mistakes are avoided. These studies would lead us to better diagnostic tools and intervention opportunity to either prevent or cure some of these diseases.

The use of fluorescence microscopy enabled us to detect a genetic rearrangement between chromosome 7 and chromosome 12 in the leukaemia cells of infant patients. In this picture, you can see (A) the ideograms of chromosomes 7 and 12 (both normal and rearranged) - the presence of green and red signals together indicates the rearrangement on the abnormal (der) chromosomes; (B) a metaphase spread where the chromosomes are visible in condensed form and tagged with fluorescent probes; (C,D and E) examples of interphase nuclei where chromosomes are not visible because are decondensed (in these images you can still see fluorescent patterns that allow you to identify the translocation when green and red signals are close to each other); (F) a schematic representation of probe combinations in the interphase nucleus. Link to the publication: http://dx.doi.org/10.7243/2052-434X-3-4

Cilia are cellular antennas that protrude from cells and sense the environment. Cilia convey signals to the cell and promote changes in cell motility and even metabolism. In the top left, in black and white we can see a basal body and the beginning of a c

The picture shows the chromosomes from one colorectal cancer cell cultured in the laboratory. The larger dark grey forms are whole chromosomes where as the small dots indicated by the red arrows are chromosomal fragments called double minutes that have broken off the main chromosomes. Double minutes are frequently found in cancer cells and the genes within them are often expressed incorrectly causing the cells to grow too fast.

Expression of mature osteoclast markers. VNR expression are present in actively resorbing, multinucleated osteoclasts. Resorption trails are clearly visible in panels E-G (*).. Bottom two images are collected using laser confocal microscopy of the coexpression of β3 integrin (green), F-actin rings (red), and cathepsin K (blue) in osteoclasts.

Obesity is on the rise worldwide, in adults as well as in children. Whilst obesity is commonly considered to be caused by an imbalance of caloric intake and energy expenditure, the increase in obese populations cannot be solely explained by poor diet and lack of exercise. Other factors, such as genetics and exposure to environmental chemicals have also been implicated. Indeed, exposure to metabolism disrupting chemicals, which act as so-called obesogens, during early development may increase the susceptibility to obesity. Several such compounds have been found to stimulate adipocyte differentiation in laboratory animals and cell-based experiments. Our research aims to develop cell culture-based assays to be able to identify chemicals which may interfere with healthy metabolism and to increase our understanding of how these chemicals act. Understanding these processes will help to investigate how exposure to obesogenic chemicals in early life can predispose to obesity. Knowing which chemicals are obesogenic can help us to prevent human exposure, especially during pregnancy and early childhood. The picture shown here provides examples of human mesenchymal stem cells which have been treated with the obesogenic chemical: Rosiglitazone, an antidiabetic drug which is known to induce adipogenesis; Cells treated with these chemicals accumulate lipid droplets, which are not observed in control cells. The accumulation of lipids indicates that a chemical is a potential obesogen. Using stem cell-based assays will help us to rapidly identify potential metabolism disrupting chemicals, reduce the need for animal testing, and create a safer environment for humans and wildlife. This research is part of the EU-funded GOLIATH project.

The image is a confocal microscope image of a 3D structure of breast cells, called acini. These cells were cultured in a gel-like scaffold, called matrigel, where they formed 3D acini that resemble milk ducts in human breast. This is formed by a layer of cells (epithelial cells) encapsulated by a membrane (basement membrane) and surrounding a hollow lumen (centre). In humans, milk would flow through the lumen. This system allows us to study breast cancer in a system that is more representative of the structure and function of the breast than traditional culture methods (where cells are grown in flat surfaces - 2D).

The image is an organ-on-a-chip system where we culture human breast cells in 3D. This system allows us to culture cells, in the lab, in a way that replicates the architecture and environment of the human breast to study the initiation, progression and treatment of breast cancer. These systems are being developed in many areas of biomedical sciences to replace or reduce the reliance on animal studies.

Systems epidemiology of metabolomics measures reveals new relationships between lipoproteins and other small moleculesTo understand why drugs to increase the "good" cholesterol (HDL) have been unsuccessful in lowering the risk of heart attacks, I investigated the functions of different sizes of the particles carrying this "good" cholesterol. I found that the smallest of these behaved very differently to what we believed and shared some characteristics with triglyceride rich particles that increase the risk for heart disease. This gets us closer to understanding the role of HDL in the body and points us towards the development of drugs that are more specific to the kind of HDL particles targeted for heart attacks prevention.

The Rams Horn Snail and host of the human parasitic disease Bilharzia.The top row displays whole chromosome territories in green in cell nuclei in blue extracted from whole snails. The bottom row reveal in red nuclear bodies and nuclear motor proteins as observed in human cells, which we have proven move chromosomes and genes around to specific locations in cell nuclei. We believe given the similarity of the genome behaviour and nuclear structure in these animals they make an excellent whole organism model to study ageing, cancer and dementia.

Human ovarian cancer cell attached on a titanium surface releasing vesicles into the culture dish. This is a process that may well happen in an ovary. The presence of these vesicles may be able to give us new avenues to create better diagnostic tests for ovarian cancer.

Precursor messenger RNA (pre-mRNA) splicing is a cellular process in which non-coding sequences (introns) are removed and coding sequences (exons) are joined together to generate mRNA for protein production in cells. Splicing is somewhat similar to film editing: if it is not done properly, two unmatched scenes may be stitched together in one episode, which would not make sense. In splicing, if exon-intron boundaries are not correctly identified, the wrong mRNA will be produced. From this a faulty protein will be synthesised, and it may cause disease. This happens in splicing of LMNA gene that leads to production of the aberrant protein, Progerin, which, in turn, causes premature ageing. Thus, the LMNA pre-mRNA splicing can be used as a tool to investigate the mechanisms that regulate human longevity. Our aim is to identify the proteins that play a key role in modulating the outcomes of the LMNA pre-mRNA splicing via comparative proteomic analysis. Since the identified proteins are likely to affect the speed of the ageing process, the pharmaceutical targeting of these proteins - inhibition of their function by small interacting molecules - may lead to the discovery of novel drugs capable of extending human life span.The image is of a gel that demonstrates how to reveal all the components of a spliceosome by elution and employing a glycerol gradient.

Transduced human cells: Green stains nuclei in which chromosomes are modified by the viral vector.

Meiosis I – separation of homologous chromosomes (from parents); Cyan: chromosomes; Red: centrosomes

Cell division, Mitosis – chromosome segregation: Green: telomeres (chromosome ends); Blue: chromosome body where condensed; Red centrosomes (pole bodies that pull chromosome into daughter cells)

In our lab, we use test the safety of viruses for gene therapy. These viruses have been manipulated so they do not give the normal illness but can be used to treat diseases. Our virus makes cells fluoresce green so we can see if the virus is working properly. In the first picture, we injected mice with a virus purified in two different methods to test if our method (ATPS) was effective. The top right picture shows cells we grew as 3D mini livers and the bottom right picture shows stem cells we grew. Both of these cells infected well with the virus meaning we can use these cells to test the safety of these viruses.

The panels represent a 3-dimensional model of foetal blood formation, built from mouse embryonic stem cells. We call these models haemogenic, or blood-forming, gastruloids.The mouse embryonic stem cells have been engineered to express a green fluorescent protein (GFP) gene in blood vessel-lining endothelial cells, some of which specialise to form blood cells, including blood stem cells. The top 3 panels show emergence of the first GFP-positive endothelial cells and progressive development of GFP-positive vascular networks in haemogenic gastruloids. Photographs were obtained at 4, 6 and 8 days of culture in the laboratory.At the bottom left, emergence of blood cells from the GFP-positive endothelial cells was captured by confocal microscopy. Round cells pseudo-coloured in red can be observed in bunches, or clusters, adjacent to flat endothelial cells shown in green. The arrangement closely mimics budding of blood cells in vivo from the vessel-lining endothelium. Round cells are labelled with an antibody against a molecule present in all blood cells, named CD45. Some of the CD45-positive cells are also pseudo-coloured yellow: this reveals the presence of another molecule named C-Kit, characteristic of immature blood cells, including blood stem cells. Blue stains all types of cells formed in the gastruloid model.Bottom right depicts a detailed analysis of the genes expressed by all blood and endothelial cells present in the day 8 haemogenic gastruloids. Gastruloids were dissociated into individual cells, and each cell was sequenced to catalogue the genes it expresses – this is called single-cell RNA sequencing, and informs our understanding of the identity and function of each cell. Individual cells are represented on a plot, where each dot corresponds to a single cell. Cells expressing similar genes in similar amounts are represented together in groups, or clusters, which are numbered. Endothelial GFP-positive cells are present in clusters 0 and 3, and blood CD45-positive cells are in clusters 1, 4, 5, and 6, with the most immature cells present in cluster 4.We are investigating cluster 4 cells for the presence of blood stem cells, which may be later expanded and used in bespoke bone marrow transplants.

The graph shows the percentage of patients who had high levels of ACBD3 protein in their tumours. ACDB3 is a protein involved in protein transport within cells. One can see that nearly all breast, colorectal, head and neck, prostate and thyroid cancer patients (left hand 5 bars) have high levels of ACBD3 whereas in lymphoma (grey – far right) only 20% of patients had high levels. ACBD3 staining is brown and the haematoxylin (blue) shows the cell nuclei. a)-d) displays ACBD3 staining in a sample from a 39 year old patient with invasive breast cancer at different magnifications. There are low levels of ACBD3 in the fibrous tissue whereas the ductal cells have higher levels of ACBD3 (Dark brown staining)

Treating breast cancer, Dr Amanda Harvey