Optimizing Mycobacterial drug discovery using picodroplet technology
Tuberculosis (TB) is a disease caused by the organism Mycobacterium tuberculosis which kills 1.5 million people each year and is thought to infect one quarter of the world’s population. Treatment of TB is becoming ever more difficult with the emergence of antibiotic resistance, and this has propagated an urgent unmet need to discover new antibiotics with novel mechanisms of action. The development of high throughput microfluidics has revolutionized the way in which we can discover new antibiotics. In this collaborative, multidisciplinary project, we aim to optimize one such platform for use in screening for antibiotics with activity against M. tuberculosis.
The successful candidate will be trained by and work with Sphere Fluidics to engineer a platform that is optimized for Mycobacterial drug discovery, controlling various aspects of bacterial culture to produce a platform that is physiologically relevant and suitable for high throughput drug discovery. Subsequently, they will transfer this platform to Aston University to the Mycobacterial Research Laboratory for use in screening a highly valuable set of anti-TB drugs, to discover their activity and investigate their mechanisms of action. The selected student will benefit from cross-disciplinary training in both engineering and biological sciences and have the opportunity to apply that training to develop technology that improves the discovery and development of novel antibiotics.
Porcine Eye Model for the Development of Ocular Surface Treatments and Contact/Intraocular Lenses
The eye is a vital organ for our sense of vision, but there are currently no established in-vitro models for the anterior eye (including the transparent window to the eye, the cornea, and the crystalline lens which allows us to focus at different distances when we are young). This project will optimise a mechanical holder to mount porcine eyes (a waste project of meat production), a fluid pump mechanism to circulate biological fluids which can maintain the physiology of these tissues for 7-10 days, and the mechatronics to simulate blinking and the muscle contraction that controls eye focus. The PhD student will work as part of a multidisciplinary team including an optometrist and ophthalmic surgeon to investigate the effects of contact lens and surgical implantation of intraocular lenses following cataract surgery. Additional projects will include accelerating the ageing of the crystalline lens, such as through growth hormones and microwaves, to simulate fibrotic changes with time
Scaling-up of keratinocyte expansion for the treatment of large burn wounds.
Skin constitutes the first line of defence against disease-causing organisms, but is susceptible to injury such as burns. Several hundred thousand people in the UK sustain burns every year, and hundreds are fatal. Most dangerously, the loss of the barrier to pathogens means that patients can succumb to overwhelming infection – sepsis – within a few weeks after injury.
The gold standard for treatment is to remove the dead tissue surgically and resurface with new skin. Full-thickness skin grafts are rarely used because there are few donor sites on the body surface, and this thicker skin is less likely to pick up a blood supply at its recipient site. There are several commercially available skin substitutes to replace the epidermis/dermis, or both; however, these options are expensive and have not yielded any acceptable long-term clinical result yet.
Recent advances utilise cell-based techniques – extracting biopsies from the patient’s skin, isolating keratinocytes and expanding them in laboratory culture. There are important limitations; time constraints, difficulties in achieving sufficient numbers for clinical application, and the possibility of instigating neoplastic change due to components added during the cell culture process.
This project aims to overcome some of these challenges by implementing novel cell culture techniques in specialised bioreactors. The key aim is to advance culture techniques that allow an optimal, accelerated growth of keratinocytes from an autograft. These expanded keratinocytes will potentially be applied to seal burn wounds, reducing morbidity and mortality after large injuries.
Cell and Tissue Engineering
Developing novel bioactive materials for bone cancer applications
Survival for bone cancer patients is poor despite the aggressive combined use of surgery, chemotherapy, and/or radiotherapy. Secondary or metastasis cancers are particularly prevalent in bone tissue locations. To improve clinical outcomes, novel therapeutic materials are required.
This interdisciplinary PhD project aims to develop and characterize new bioactive materials to improve clinical outcomes for patients suffering from bone cancer. Materials will developed to provide a control release of key metal ions to selectively induce tumour cell death and simultaneously stimulate new bone growth.
The project will build on previous studies undertaken within our group. The successful candidate will undertake a series of in-vitro studies to fully characterise these materials with the aim of developing and optimising materials for clinical applications. The project will involve working with cell lines and primary patient tumours.
Cell and Tissue Engineering Cell Testing Translation and Manufacturing
Bioactive glass microcarriers for the expansion and recovery of hMSCs for the treatment of pseudarthrosis following Adult Spine Deformity surgery
Pseudarthrosis is a failed solid bone fusion at a minimum follow-up of 6 months after surgery to correct adult spine deformity (ASD). It can lead to reduced quality of life, loss of correction and progression of deformity, and it represents the primary cause of 4-24% of all revision fusion surgeries. Cell therapy using the patients’ own mesenchymal stem cells (hMSCs) has shown considerable promise for non-healing bones, but producing the necessary cell dosage for successful treatment can be a real challenge. Although stirred-tank bioreactors containing off-the-shelf microcarriers have become the method of choice for the expansion of hMSCs, successful recovery of the cells from the microcarriers without sacrificing cell quality and yield can prove challenging.
The aim of this project therefore is to investigate a novel type of microcarriers fabricated from biodegradable glass, to be used for the scalable production of hMSCs for the treatment of pseudarthrosis after ASD surgery. Following their design, manufacture and extensive characterization, the bioactive glass microcarriers will be used in stirred-tank bioreactors for the expansion and subsequent non-enzymatic detachment of hMSCs. Process parameters (agitation, feeding regimes, degradation rate and harvest time), as well as final cell yields and hMSC quality will be compared against the use of commercial microcarriers and traditional cell detachment/harvest protocols employing proteolytic enzymes.
Translation and Manufacturing
Creating a 3 dimensional skin substitute to model normal skin, wound healing and scarring using PODSTM technology
Cell Guidance Systems occupies modern research facilities on the Babraham Research Campus near Cambridge. Babraham provides a vibrant research atmosphere for over 1,000 researchers and hosts some of Europe’s most successful biotech companies. In addition to our own well-equipped labs, we have access to shared facilities on the campus.
PODS® technology is the primary research interest of the company. The company has multiple programs of research and collaborations in areas as diverse as biomaterial development, Parkinson’s disease and osteoarthritis, amongst others.
The student would become part of the PODS® group and gain fundamental knowledge about PODS® biology. During their time at the company, the student will be expected to produce at least one PODS® protein that they will use in their own research. They will also be expected to work closely in collaboration with our recent KTP Associate – a PhD level materials scientist who joined the company last year.
In addition to R&D activities, the company has a commercial division which offers research products and services. The candidate will take part in meetings and gain valuable exposure to commercial activities. This will prepare them to understand the commercial world, and will be particularly useful if they remain in academia.
On-Demand Sensors for Cell Therapy Bioprocessing
The project will include an industry placement with the Cell and Gene Therapy Catapult at Guys Hospital, London Bridge, London. The placement will enable the student to gain an understanding of the roles of process development and analytic/data analysis teams. They will apply their knowledge and the technology generated to a range of scalable bioreactor cell cultures and to gain a deeper understanding of typical industry workflows, by working with one of the leading translational cell and gene therapy institutes in the world. It will also enable the student to understand the wider commercial and R&D ecosystem that underpins the regenerative medicine sector.
Development of Advanced Endospectroscopic Nanotechnology for Inflammatory Bowel Disease: From tissue, through early diagnostics to personalized therapy
The PhD project is of a highly interdisciplinary nature, and lies at the interface between biomedical engineering, biosciences and medicine. It will focus on developing and engineering new methods for improved, accurate detection and assessment of IBD lesions and tissue healing as well as understanding, monitoring and controlling the cellular and tissue responses to therapeutical treatments.
The research will include development and engineering of novel, integrated endscopic and Raman techniques and tailored microfluidic lab-on-a-chip to enable early-detection of IBD and its disease activity, neoplastic changes and healing at nearly histological level and delivery of successful stratification and tailored therapy to individual patients. By restoring and maintaining diseased tissue and organs, the outcome of this research will lay a platform towards
Cell and Tissue Engineering, Cell Sensing and Cell Testing, Translation and Manufacturing
Control of ECM organization and the mechanical environment in a 'Joint on a chip' device
‘Organ on a chip’ (OOAC) devices provide new miniaturized culture systems for co-culture of multiple tissues such as in the joint. These tools offer new approaches for screening of new drug targets and for diagnostics in studying disease. These devices organise multiple cell types from complex tissues in potential 3D environments with or without dynamic loading. The development of effective biological scaffold materials for OOAC devices relies on the ability to present precise environmental cues to specific cell populations to guide their position and function. Ordered dynamic nano-scale structures such as fibres in the extracellular matrix can modulate cell behaviors in health and disease. Understanding the role of dynamic environments on joint behaviour is fundamental to these model. In this project, we set out to establish natural gels such as collagen with defined oriented fibre architecture. Using magnetic forces, we will position magnetic micro and nanoparticles in a defined 2-dimensional magnetic array which guides the self-assembly of fibrils remotely and dynamically. These topographic fibres can allow the investigation of fibre orientation during health and disease in the tissues of the joint. In addition, the targeted magnetic nanoparticles (MNPs) can be used to provide mechanical stimuli to the cells remotely in a controlled intermittent manner. In addition, we will deliver different mechanical profiles to cells in the chip through targeted MNPs and design complex load profiles in an chip device..The micro-tissues investigated will be cartilage, bone and tendon.
Droplet based microfluidics for probing the metabolom of cells
Droplet microfluidics have shown exceptional promise for cell and tissue engineering, single cell study, cell testing and sorting. This typically involves complex experiments, which require a microfluidic platform to be able to perform multiple functions on each droplet. In this project, we will focus on different cell types and examine their behavior when exposed to different environments in order to understand how cells can be influenced and how to cause desired differentiations. This application if highly relevant for cell engineering, as well as medical exposure studies.
The student will exploit state-of-art microfluidic techniques to design and fabricate new prototypes and devices to probe the response of multiple cell types to different environments. This encompasses the use of established methods like soft-lithography and molding but also requires gaining expertise in more advanced techniques combining microfluidics with optical, dielectrophoretic and acoustical setups. Droplet based microfluidics is essential and the key and the student will become an expert in all aspects of this technology.
This project will allow us to both probe cell behavior in controlled environments and to look for beneficial cellular responses.
Label-free physical biomarkers for next generation cell sorting
Flow cytometry is a cell analysis technique which can make measurements of cells in solution as they pass by the instrument’s laser at rates of 10,000 cells per second (or more). Because of its speed and ability to scrutinize at the single-cell level, flow cytometry offers the cell biologist the statistical power to rapidly analyze and characterize millions of cells. An extension of flow cytometry is the sorting module, allowing physical separation of the cells based on a real-time reading in the analysis module, leading to the effective isolation of sub-populations based on the extent and presence of a specific cellular marker. The current method of single cell sorting are based on fluorescent tags, directed against specific molecular targets. While this approach provides high selectivity and specificity, it is not always possible to find a unique label for a specific biological condition. Recently this limitation has been tackled by means of label-free cytometers, measuring physical parameters of the cells such as the dry mass or the elasticity. The proposed project aims at leveraging the full power of this concept, integrating the analysis with the sorting, and addressing single cell label-free sorting. The new technology will be applied to the isolation of stem cells for regenerative medicine and to the identification of Leishmania infections in the blood. Development of label free techniques will increase the power of the drug discovery pipeline for many conditions from infection, to stem cell therapies to cancer treatments.
From the bee’s knees to biotechnology: Resilin-based hydrogels for cell-culture and bioprinting
Hydrogels belong to the most promising materials for cell-culture and tissue engineering. While biocompatibility and degradability of hydrogels are vital for use in cell-culture, mechanical properties have a significant impact on the cell differentiation. Therefore, hydrogel systems with well-controlled and tailorable mechanical properties are highly sought after. The present project will investigate the use of resilin in hydrogel fabrication as an environment for cell-growth with the ultimate goal of tissue engineering. Resilin has remarkable properties (as an elastomer it is literally the bee’s knees), which facilitates the introduction of a broad range of mechanical properties together with crosslinking chemistry, e.g. via carbon nitride in the visible light. Moreover, the project will make use of a modular approach to introduce further functions into the hydrogels in order to enhance cell-growth. Overall, the project will give rise to new robust ‘tuneable’ gels that will address many of the shortcomings of existing cell culture media and new biomaterials for 3D printing.
3D microenvironments to support improved hepatocyte maturity for liver toxicology screening.
Liver toxicology assays in drug screening is a major area of Pharma research. Use of animals in the field in prevalent and alternatives are urgently required. Cytochroma have developed spheroid culture assays that require better phenotypical stability. It is likely that appropriate 3D culture, using hydrogels, will be key to achieving this. However, normally such models rely on matrices with poor batch to batch reproducibility derived from animal products such as collagen.
In this project, we will design new in vitro models using peptide-based gels. The project will be highly multidisciplinary, and involve aspects of synthesis, gel formation and characterisation, as well as using the gels as cell scaffolds. Our ultimate aim is the development of bio- and mechano-optimised scaffolds that support hepatocyte spheroid phenotype.
New platforms for the sustained release of growth factors: Reprogramming cells to new functional identities.
Peripheral nerve repair (PNR) is an area of plastic surgery where repair at an organ level is possible, but failure occurs at the cellular level, especially where a longer (3cm+) gap has to be bridged. To improve outcomes for PNR over a critical gap, cell therapy that uses conduits filled with Schwann like cells, differentiated from adipose derived stem cells (ADSC) has been proposed. If successful this system could be tested in vivo for effectiveness and a similar system developed to differentiate human iPSC into DRG neurons for placeholder purposes. This PhD studentship will develop novel sustained release platforms for the delivery of drugs and growth factors to reprogramme cells to new functional identities. The student will develop a wide range of cross-disciplinary skills including polymer synthesis and characterization, characterization of molecular assemblies, cell isolation and cultivation, iPSC culture, qPCR, flow cytometry, ELISA, immunocytochemistry and microscopy. They will be working with cutting edge techniques such as molecular spectroscopy (e.g. NMR), sustained and tuneable drug release systems and simple soft microfabrication. Furthermore, this PhD studentship offers a placement with a biotech company in Cambridge, UK, developing the innovative PODS® technology, a crystalline sustained-release technology for proteins.
Bioengineering of Pharma ready bone marrow models for cancer drug screening
Being able to control haematopoietic stem cell (HSC) growth out of the body, out of their niche, is a major goal of stem cell biology. It would make HSC therapies, such as bone marrow transplant for leukemia treatment, more available by transforming them to become one donor – multiple recipient therapies. It will also allow us to develop in vitro niches to e.g. perform CRISPR on cancerous HSCs to provide autologous curative therapies.
In our laboratories, we have worked to understand how the partner cells of HSCs in their niche, the mesenchymal stem cells (MSCs), are regulated by materials interfaces. This is important as MSCs, that interact with the extracellular matrix in the niche, control HSC growth and self-renewal through cell-cell interactions and paracrine signalling. The understanding we have developed has enabled us to demonstrate that we can bioengineer in vitro niches where MSCs regulate HSC growth to maintain more of the most regenerative HSCs in culture for longer.
In this exciting new project, the student will develop 3D niche models for HSC growth using microbeads coated in our novel polymers that control how the extracellular matrix is presented to MSCs in order to produce HSC supportive MSC phenotypes. Further, we will work with our industrial partner, Atelerix, to place these marrow microtissues into their hydrogel systems that allow prolonged cell survival at room temperature. This step will be important for translation of our technologies into Pharma use by making them off-the-shelf, reproducible and easy to use.
The student will join a thriving lab with good links to clinic and to industry and where they will be provided with world-class multidisciplinary training. This will equip the student well for their next career steps.
Theoretical modelling of cell response to external cues
Cells and tissues respond to mechanotransductive and biochemical cues. These external cues interact with protein signaling pathways within the cell and can trigger changes in size, structure, binding and differentiation. This project will use theoretical modelling to examine the response of an array of cells to various external mechanical and biochemical cues, considering how these cues can be tailored to optimize a particular outcome. The model will couple the mechanical components of the cell (nucleus, cytoskeleton,…) to internal protein expression pathways (Myosin II, MLCK,…) and the properties of the external stimuli. The model will take the form of coupled differential equations which will be solved using both analytical and numerical methods.
This model will be validated against experimental data in two main ways, including examining the response of the array to small amplitude mechanical vibration (‘nanokicking’) to predict its influence on the behavior of the array over long timescales. The model will also be used to understand growth factor delivery using PODS® technology developed by Cell Guidance Systems to predict the optimal spatial arrangement of PODS® relative to the array and the resulting temporal and spatial profiles of both the growth factor and the cell growth and proliferation.
Cell and Tissue Engineering, Drug Discovery