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Spotlight on ...

The role of immunohistochemistry in patient stratification and personalised medicine

Not all patients respond well to treatment and drugs have failed in the clinic due to “all patient” designs. Immunohistochemistry (IHC) could be used to group patients according to the expression levels of a specific biomarker. With successful validation and quantification, IHC assays can play a vital role in drug development as a method of patient stratification.

A stromal cell population that inhibits adipogenesis in mammalian fat depots

Adipocyte development and differentiation play an important role in the origin of obesity and many related diseases such as type 2 diabetes and cancer. Using a single-cell transcriptomics-based approach in a mouse model revealed three different adipocyte progenitor cell populations, including one subpopulation, termed Aregs, that suppressed adipocyte formation in vitro and in vivo.

Determinants of variability of five programmed death ligand-1 immunohistochemistry assays in non-small cell lung cancer samples

Upregulation of PD-L1 is associated with increased risk and tumourigenicity of cancers, helping many escape immune surveillance. PD-1/PD-L1 expression has been suggested as a possible biomarker for identifying patients that may be sensitive to PD1/PD-L1 immunotherapies. Current PD1/PD-L1 testing procedures may not be sufficient to distinguish responders and this study aimed to simplify the process by assessing the different methods on clinically-relevant NSCLC samples, to identify factors relevant for PD-L1 detection and make assays more robust and reproducible.

The influence of TLR5 expression by intestinal epithelial cells on the gut microbiome

It has been shown that TLR5 expression by the intestinal epithelium early in neonatal development is an important factor in preventing increased colonisation by flagellated bacteria, which can drive chronic pathologies such as metabolic syndrome and colitis

Acute Lymphoblastic Leukaemia highjacks a neural mechanism to invade the CNS

Acute Lymphoblastic Leukaemia (ALL) most often metastasise to organs such as the spleen and lymph nodes, but also to the Central Nervous System (CNS). Here, Yao et al show that ALL cells infiltrate the CNS not by breaching the blood-brain barrier, but by hijacking the neural migratory pathways.

Gene expression profiles from plucked scalp hair to assess pharmacodynamic biomarkers following treatment of advanced solid tumors with a novel anti-cancer stem cell Wnt inhibitor

Wnt signaling pathway genes are crucial for cell fate determination and cell polarity during development. Ipafricept (OMP-54F28) is a first in class recombinant fusion protein producing a truncated decoy receptor that binds to a cystine-rich region of Wnt ligand and as a result it blocks the activation of the Wnt signaling. Here the authors described the results of a phase 1 first in-human clinical trial.

Improved healing of large wounds via the reprogramming of wound-resident mesenchymal cells into epithelial cells

The authors of this paper demonstrated that mesenchymal cells within a large wound could be converted into keratinocytes in vivo via the transduction of four genes. This improved re-epithelialization of wounds through generation of new epithelial tissue that showed normal morphology/characteristics and eventually connected to host skin. The paper provides proof of principle for a new wound healing treatment particularly useful for large wounds that normally require skin grafts.

Two recent papers highlight the importance of tumour microenvironment on cancer cell stemness

Two recent papers demonstrate the importance of the tumour microenvironment on its progression through in vitro co-culture. The authors in one paper show that M2 macrophages increase the stem cell capacity of an ovarian cancer cell line, whilst in the other fibroblasts increase the stemness of a lung carcinoma cell line. They highlight the importance of considering the tumour microenvironment in in vitro experimentation, and also reveal potential new therapeutic targets.

CAR-T Cells in cancer Therapy

Summary of a paper reporting an unusually delayed response from one patient during a clinical trial in CLL using CAR T-cells targeted to CD-19 that may shed light on some of the mechanisms determining persistence of CAR T-cells and their clinical outcome.

Memory of EpSC in Wound Healing

Summary of a study investigating how skin inflammation effects EpSCs to allow them to speed up barrier restoration following subsequent tissue damage.

4PD1hi cells predict response to immunotherapy

4PD1hi cells predict response to immunotherapy

Can changes to gut microbiota affect the efficacy of chemotherapies?

Can changes to gut microbiota affect the efficacy of chemotherapies?

Oncogenic JAK2V617F causes PD‑L1 expression, mediating immune escape in myeloproliferative neoplasm

Oncogenic JAK2V617F causes PD-L1 expression, mediating immune escape in myeloproliferative neoplasms

Glut1 – A target for Psoriasis treatment

Glut1 - A Target for Psoriasis Treatment

Targeting breast cancer with Hsp70‑aptamer‑guided nanoparticles with chemotherapeutic payloads

Targeting breast cancer with Hsp70-Aptamer-guided nanoparticles with chemotherapeutic payloads

The relationship between epithelial cell fate, microbiota composition and inflammation in the intestine

How perturbation of the homeostatic mechanisms governing epithelial cell fate in the intestine influence the gut microbiota and the susceptibility to colitis. The influence of structural proteins on key signalling pathways and their downstream transcriptional machinery are discussed.

CAR-T Cells: Engineering Immune Cells to Treat Cancers

For many years surgery, chemotherapy and radiation therapy have been the foundations of cancer treatment. Over the last two decades, targeted therapies have cemented themselves as standard treatments for many cancers and over the past several years, immunotherapy therapies that enlist and strengthen the power of a patient’s immune system to attack tumours has emerged.

Epistem Analytical Protein Services – Flow Cytometry and Luminex®

Epistem offer protein analysis as a vital readout of Test Item efficacy in vivo and in vitro. At Epistem, we offer 2 automated platforms that can be used to analyse proteins in cells and liquid samples - flow cytometry and Luminex

Laser Capture Microdissection (LCM) - A Strategy for Success

Micro-sampling by laser capture microdissection is a powerful tool allowing specific analysis from whole tissues, in heterogeneous microenvironments such as tumours, where less well represented target cells are dwarfed by tissue stroma and other cell types. Whilst the application is potentially powerful for target discovery and mechanistic understanding, the process is notoriously difficult, particularly in clinical specimens. Our Laser Capture Microdissection team has evaluated the findings from all the studies run in our GCLP-accredited labs and devised a strategy for LCM studies maximising the potential of success and giving the sponsor control over go/no go decisions.

CCDC88B and its Importance in Inflammatory Bowel Disease

Epistem have extensive experience of running in vivo colitis models including off-the-shelf models of adoptive T cell transfer-mediated and DSS-induced acute colitis; in addition, we are happy to develop and run bespoke models in collaboration with Sponsors.

Choosing the best preclincal oral mucositis model to demonstrate efficacy or Mechanism of Action

The oral mucosa is a stratified squamous epithelium that has a crucial barrier function. Any damage or loss of integrity during oncology therapies poses a major risk of infection, since such patients are often also immunocompromized. Furthermore, the large ulcerations can be so painful that patients are often unable to eat and require hospitalization and enteral nutrition.

Antibody Validation: Does the antibody really recognise what it says on the label?

Epistem has an expert histology lab whose capabilities are available as a standalone service, or integrated to add value to your preclinical model. Nicola Tonge, Epistem's Histology Manager and IHC specialist discusses the issues faced when choosing the correct antibody as there is currently no industry standard for antibody validation, and not all antibodies work 'how they say on the label'.

Epistem Bioinformatics Services

Epistem's pharmacogenomics division have provided biomarker discovery and validation studies with many sponsors. The bespoke nature of many of Epistem's services mean that bioinformatics analysis is always tailored to the nature of the study.

Gene expression analyses of murine skin highlight strain-dependent effects of Imiquimod on psoriatic signatures

Our gene expression analysis and detailed protein analyses by flow cytometry and Luminex® can further assess disease pathogenesis by the identification of key molecules, or the intracellular mediators they express (cytokines, transcription factors).

JAK2, a novel therapeutic target in lung adenocarcinoma?

The field of personalised medicine to provide understanding of the molecular basis of disease is constantly growing. Multiple signalling pathways have been identified that associate with malignant transformation. However, the vast majority of lung cancer patients have no known driver genes detected, and they are still treated with standard cytotoxic chemotherapy.

Platelets are major suppressors of T cell function

We currently offer validated models to address immune function in tumour bearing mice. Our detailed flow cytometric expertise can further assess the identity of tumour infiltrating and peripheral cell populations such as CD8+ T cells, MDCSs and regulatory T cells, by surface identification of key molecules, or the intracellular mediators they express (cytokines, transcription factors).

Adoptive T Cell Transfer Models of Colitis

This model offers the ability to study test items using a range of dosing regimens, from dosing in a prophylactic manner through to examining efficacy in ameliorating early stage or established disease.

CCL20 as a biomarker of drug efficacy in IBD

The chemokine CCL20 (Mip-3α) plays an important role in recruiting Th17 cells (which express the corresponding receptor, CCR6) to sites of inflammation, thus playing a role in the pathogenesis of chronic inflammatory conditions such as Crohn's disease. In a recent paper in the Journal of Crohn's and Colitis, Giovanni Monteleone and colleagues presented data from clinical and laboratory studies on Mongersen, a Smad7 antisense oligonucleotide.

Development of a Signature of Aberrant Myc Transcription has Prognostic Value in Evaluating Novel Myc-Targeted Therapies

Altered expression of transcription factors are key indicators in cancer progression in functions such as proliferation and differentiation, angiogenesis and apoptosis. A significant proportion of cancers are driven by mutations in these networks, including Wnt/β-catenin, Ras/MAPK and Myc

A new paper demonstrates that BMP limits Lgr5+ stem cell number in intestinal epithelial cells

The paper demonstrates that BMP acts via Smad to transcriptionally repress a range of stem cell associated genes, including Lgr5, and that this is independent of the Wnt//β‑catenin signalling pathway.

A new opportunity to reduce scarring by converting myofibroblasts to adipose cells?

Epistem has validated in vivo excisional and incisional, human skin engraft, diabetic and LPS-induced inflammation wound healing models. In vitro wound healing assays are also available to assess cell proliferation/migration, wound closure and angiogenesis.

On-going Mechanical Damage from Mastication Drives Homeostatic Th17 Cell Responses at the Oral Barrier

we currently offer in vivo models of rheumatoid arthritis, psoriasis and inflammatory bowel disease.

Accessing Disease End-Points in IBD Models

High quality histopathology analysis is standard for all our IBD service models. In addition, Epistem offer a wide range of analytical services that allow Sponsors to acquire quantitative experimental data for a variety of disease-relevant end-points.

Laser Capture Microdissection for Gene Expression Analysis in Distinct Cell Populations

Knowledge in early phase cancer development to provide understanding of the mechanism of action of oncogenic mutations is constantly growing. A recent study carried out by Mo et al has highlighted several interesting results.

New paper demonstrating the microbiota impact on cell proliferation via microRNA expression changes in intestinal epithelial stem cells

Intestinal flora are known to impact the immune system and metabolism, with chronic exposures to certain flora linked to conditions such as inflammatory bowel disease and fibrosis. Breeches of the epithelial barrier and systemic infection can lead to more acute problems such as sepsis.

New biomarker/therapeutic target in AML

The field of personalised medicine to provide understanding of the molecular basis of disease and the mechanism of action of chemotherapeutic drugs is constantly growing. A recent study carried out by Schneider et al has highlighted several interesting facts.

Citrulline as a Biomarker of GI Toxicity

Citrulline is produced by small bowel enterocytes, with circulating citrulline levels correlating with enterocyte mass. Changes in enterocyte number (or in some cases function) are therefore reflected in plasma levels. As a result, citrulline levels may be a biomarker for various GI syndromes

The Tumor Microenvironment Represses T Cell Mitochondrial Biogenesis to Drive Intratumoral T Cell Metabolic Insufficiency and Dysfunction

we currently offer 3 models to address the immune response in tumour bearing mice. Metabolic and mitochondrial function of T cells can be assessed by flow cytometry. Our detailed flow cytometric expertise can further assess the identity of tumour infiltrating and peripheral cell populations, by surface identification of key molecules, or the intracellular mediators they express (cytokines, transcription factors).

Multiplexing Immunohistochemistry: A new method for integrating biomarker expression

Multiplexed biomarkers and diagnostics can provide a greater understanding of the response of a tissue to a drug, or of disease stage, allowing further progress towards personalised medicines.

Novel drug prevents AML cells from hiding

It’s generally accepted that leukaemic stem cells can lodge in the protective bone marrow niche, thereby escaping chemotherapy and with time potentially initiate a relapse.

Plucked hair ex vivo model identifies novel Notch PD biomarker suitable for use in the clinic.

Epistem have validated plucked scalp hair as a robust ex vivo model allowing biomarker signature identification. Readouts in these models include expression profiling by microarray or RNA-Seq, and targeted assays by qPCR.

New insights into epithelial barrier dysfunction in the intestine: relevance for IBD

Alterations in the complex inter-relationship between intestinal epithelial cells, the mucosal immune system responses and the gut microbiota are responsible for the development of inflammatory bowel disease in humans.

FDA approval for new diabetic wound dressing.

Epistem validated in vivo diabetic wound healing model showing delayed wound healing (wound closure and re-epithelisation) and a decreased inflammatory response.

Novel sunscreen ingredient demonstrates high protection from UVA radiation

Epistem have validated 3D and 2D skin models. 3D models include organ cultures and the human living skin equivalent that closely resembles fully stratified human epidermis with a dermal region. 2D models include monolayer cultures of primary epithelial and dermal cell types.