Gibson Group News
Our work highlighted in ERC Horizon Magazine
Our work on developing new materials which can impact the growth/formation of ice, and the development of macromolecular cryoprotectants has been featured in the ERC (European Research Council)'s Horizon Magazine. It also features some other exciting ERC-funded research in cryobiology.
Selectively targetting cancerous cells with nanoparticles by glycan metabolic labelling
We have a large program to explore the use of glycans for sensing and delivery applications. All mammalian cells are covered with glycans (the glycocalyx) which is responsible for a huge range of roles, from signalling to sites for pathogen-binding. We have previously explored how we can use metabolic oligosaccharide engineering to install non-natural glycans (sugars) onto cell surfaces, allowing us to 'do chemistry' on the cell surface in a bio-orthogonal manner. In this work, led by Prof Ben Boyd (Monash University), we explore how different cell types take up and display a cyclo-alkene (suitable for 'click' chemistry) bearing glycan, and use these differences to capture nanoparticles (with azides) onto the surface of the cells, leading to internalisation. Cells with the fastest growth rate processed the glycan faster, and hence lead to more nanoparticle capture. As cancerous cells are often characterized by increased metabolic rates, this may offer an opportunity to improve the targetting of nano-therapeutics by the highly selective formation of a covalent bond, rather than relying on unspecific physicochemical properties or targetting ligands.
Read the work here!
The impact of protein corona on glycosylated nanorods for biosensing
We have a large program to explore the use of glycans for sensing and delivery applications. By installing glycans, using a polymeric tether, onto gold nanorods we can exploit their unique optical properties, allowing us to detect if a protein binds to the glycans. Rod-shaped (compared to spherical) gold particles are exciting, as they have an additional SPR ('colour') band, which does not overlap wiht the background from e.g. blood/serum, unlike spherical gold. In our latest paper we explore how the proteins found in serum can impact on this biosensing due to non-specific fouling (sticking to form a biocorona) to the particle surface. This is a major challenge in nanomedicine/diagnostics as this fouling always occurs. Indeed, we observed that serum proteins do bind to the nanoparticles, and compared the biosensing in comparison to a model buffer solution. Interestingly, despite the biocorona formation we could still detect a lectin (glycan binding protein) BUT, it was show that the response was due to displacement of the biocorona. This meant that after binding there was less mass on the surface, than before, which was not expected. This displacement mechanism is useful as it shows our polymer-tethering strategy can be used to prepare nanoparticles suitable for use in complex media. This was a collaboration with VITO in belgium as part of a EU wide project.
Read the paper here
Cryopreservation of blood using polyampholytes
Red blood cells underpin larges amounts of trauma medicine, and other areas. TO ensure constant supply, one solution is to freeze (cryopreserve) the blood, and this is currently achieved by using glycerol. Before the blood cells can be transfused the cryooprotectants must be washed away, using a series of washing buffers, which leads to some loss of RBCs. In our latest publication, we explored alternative cryoprotectants based on DMSO and trehalose, with the addition of a polyampholyte, which we have previous found to be useful for the cryopreservation of nucleated cells. Following a screen of the different compositions, we identified a mixture which enabled <3 % post-thaw heamolysis (damaged blood cells). Following washing the total recovery was 80 %, which considered this was done manually, with no automated washing was a very signifcant result. We used microscopy and ATP assays to further confirm these results and even showed the system works in a 'blood bag'.
Read the work here
Iceni Diagnostics sign global license for our detection technology
The group has a major research interest in the development of new tools for biosensors and diagnostics, particular exploiting glycan (sugar) binding interactions. Last year we used our sensors to discover that SARS-COV-2 (causative agent of COVID-19) could bind to sialic acids, found on cell surfaces. The underlying technology to this has now been licensed to Iceni Diagnostics Ltd, who we have partnered with for the past 2 years in this field, to integrate our technology into their portfolio of new diagnostics.
This work was funded, in part, by BBSRC and shows how fundamental science can lead to technology transfer and that academic/industry partners can work together to find solutions to global problems.
Exploring the role of proline on cellular cryopreservation
We have a significant research program exploring and discovering new tools to improve cellular cryopreservation. We have been particularly interested in how to cryopreserve cell monolayers - cells attached to the tissue culture plastic. in our latest work (and the final publication from Trisha Bailey's PhD) we looked at the impact of proline (the amino acid) on cryopreservation outcomes. Extremophile rganisms produce proline in anticipation of cold stress, along with other osmolytes. However, we saw here that proline appears to slow the growth rate of cells in culture and 'prepare' them for cold stress, whereas other osmolytes had their normal function only. This pre-incubation dramatically increases post-thaw recovery of the cells and provides a simple tool for improving outcomes. Furthermore this shows we might be able to use chemical biology tools to program cells to be 'ready for cold'.
Read the paper here
Matt featured in Royal Society Campaign on EU funding
The Royal Society is running a campaign to promote the benefits of the UK being able to access EU funding opportunities. The GibsonGroups work has been highlighted, specifically on how the EU funding (ERC starter grant) provided long term fundamental science support, but also allowed translational opportunities via proof of concept grants. The Group's work in this are has lead to the formation of a spin out company, Cryologyx Ltd, which would not have been possible without this support.
Minimal ice binding peptides discovered using phage display
Our latest work on non-standard ice binding materials has been published in Nature Communications. In this work, we used phage display - a high -throughput technique which enabled billions of short peptides to screened for their ability to bind ice crystals. This lead to the discovery a small, 14 amino acid, cyclic peptide sequence which was a potent ice growth inhibitor. This work was a collaboration with Harm-Anton Klok (EPFL Switzerland) and Dr Corey Stevens, who visited Warwick several times to undertaken much of this research. We also collaborated with the Sosso Group at Warwick, who provided modelling expertise to understand how such a small peptide can bind ice. The peptide was also used as a 'CryoTag' to enable purification of proteins by a simple ice-binding process. The work is important as this peptide is easy to synthesise by solid phage peptide synthesis, allowing access for more experiments and can be easily modified for further study.
Read the paper here
A Minimalistic Cyclic Ice-Binding Peptide from Phage Display