Linking GPCR organization states with functional heterogeneity in the pancreatic islet
Lead Research Organisation:
University of Oxford
Department Name: RDM OCDEM
Abstract
The current view of tissue complexity is mainly based upon single-cell screening technologies, which classify cells according to shared traits, such as maturity, proliferative capacity and mutational potential. Often, inferences about cell function are based upon measurements made outside of the tissue context, as well as the characteristics of the state to which the cell belongs. Thus, immature cells tend to be considered as proliferative, but poorly functional, whereas more mature cells are long-lived and highly functional. While single-cell screening approaches are high-dimensional, they do not have the spatiotemporal resolution inherent to light microscopy. The present proposal will leverage recent advances in genome editing, protein labelling, super-resolution imaging and spatial transcriptomics to provide a higher-order in situ organization of cell heterogeneity at the tissue level, with repercussions for our understanding of tissue (dys)function. Using pancreatic islets as an exemplar micro-organ, and GPCRs as candidate cell surface signalling proteins, we will: 1) map GPCR organization/dynamics at the cell population level and integrate this information with underlying transcriptomic features, before re-classifying cell states; 2) understand how higher-order GPCR organization/dynamics change during cell stimulation, metabolic stress and other states of tissue perturbation; 3) functionally interrogate cell states defined by GPCR organization/dynamics using novel activity integrators and cell-specific transcription factor re-expression; and 4) examine higher-order cell heterogeneity across species. The proposed work will show for the first time how the organization and dynamics of individual signalling proteins relate to cell state and cell activity across the cell population. More broadly, these studies will establish a high-resolution view of cell heterogeneity, leading to a step-change in our understanding of the functional organisation of complex tissues.
Publications
Adriaenssens A
(2023)
Hypothalamic and brainstem glucose-dependent insulinotropic polypeptide receptor neurons employ distinct mechanisms to affect feeding.
in JCI insight
Ast J
(2023)
Revealing the tissue-level complexity of endogenous glucagon-like peptide-1 receptor expression and signaling.
in Nature communications
Collins J
(2024)
Peptide-Coated Polycaprolactone-Benzalkonium Chloride Nanocapsules for Targeted Drug Delivery to the Pancreatic ß-Cell.
in ACS applied bio materials
Cuozzo F
(2024)
LDHB contributes to the regulation of lactate levels and basal insulin secretion in human pancreatic ß cells.
in Cell reports
Firth G
(2023)
Impact of an SLC30A8 loss-of-function variant on the pancreatic distribution of zinc and manganese: laser ablation-ICP-MS and positron emission tomography studies in mice.
in Frontiers in endocrinology
Galvis D
(2023)
Spatial distribution of heterogeneity as a modulator of collective dynamics in pancreatic beta-cell networks and beyond.
in Frontiers in network physiology
Mendive-Tapia L
(2023)
Acid-Resistant BODIPY Amino Acids for Peptide-Based Fluorescence Imaging of GPR54 Receptors in Pancreatic Islets.
in Angewandte Chemie (Weinheim an der Bergstrasse, Germany)
Mendive-Tapia L
(2023)
Acid-Resistant BODIPY Amino Acids for Peptide-Based Fluorescence Imaging of GPR54 Receptors in Pancreatic Islets.
in Angewandte Chemie (International ed. in English)
| Description | Research is progressing as expected, with a number of work packages already secured. Significant new knowledge generated: we have shown that GLP1R- the major diabetes/obesity drug target- is enriched on the membrane of pancreatic beta cells that are located next to alpha cells. GLP1R senses glucagon released by alpha cells, which primes beta cells to respond to high glucose with insulin release. Failure of this mechanism during diabetes leads to reduced insulin release. We have therefore discovered a new mechanism by which insulin release is regulated within the pancreatic islet, with relevance for targeting by GLP1R agonist-based drugs. New or improved research methods or skills: as part of our studies, we have developed fluorescent agonists that target GLP1R and its counterpart, GIPR. We have had to do this, since antibodies against GLP1R/GIPR are norotiously unreliable, and can't be used in live cells, which precludes some important experiments such as flow sorting/live imaging. Using these reagents, we have provided updated knowledge of GLP1R/GIPR distribution- and in doing so- have revealed the cell targets accessed by drugs such as Ozempic and Mounjaro, the major diabetes and obesity drugs. Importantly, we have distributed these reagents via Celtarys Research to hundreds of labs worldwide, who have revealed many new facets of GLP1R/GIPR drug action, with knock-on effects for how we improve these drugs for use in patients. Significant negative results and/or research paths closed off: we have shown that GLP1R is a beta cell-specific marker, meaning that the suppressive actions of Ozempic on glucagon secretion are indirect. This is important knowledge, since it also explains the improved efficacy of dual agonists such as Mounjaro, which instead increase glucagon secretion. We have also leveraged the beta cell-specific nature of GLP1R to deliver gene therapies into beta cells, so a negative result has in fact become a positive. Particularly noteworthy new research networks/collaborations/partnerships: we have established a number of new collaborations, in particular with labs expert in regenerative medicine. We have also established a collaboration with Novo Nordisk as part of their Novo Nordisk-Oxford Fellowship scheme, which provides access to drug target validation expertise. |
| Exploitation Route | Academic: Our findings on GIPR/GLP1R, as well as the reagents/tools that we generated, have already been taken forward by a number of labs. For example, our chemical probes for GLP1R/GIPR visualization have been used by other labs to show that obesity/diabetes drugs target the heart, kidney and lungs, which can account for some of the beneficial off-target effects of this drug class (e.g. reduced cardiovascular mortality, reduced chronic kidney disease etc.). Furthermore, the discovery that beta cells sense glucagon via GLP1R will be taken forward by a number of labs who are focused on alpha cell-beta cell signaling, which is currently a topic of high interest due to its potential involvement in glucose homeostasis and thus diabetes. Non-academic: Our findings on GLP1R as a mature beta cell-specific marker are relevant for the generation and optimization of human-centric, disease-relevant target validation models. In particular, there is a lack of platforms for human beta cell screening, which leverage genomic studies. We are actively working with industrial partners on developing such platforms. |
| Sectors | Healthcare Pharmaceuticals and Medical Biotechnology |
| URL | https://www.celtarys.com/product-category/glp1-receptor-glp1r |
| Description | Research: We have revealed the nuts and bolts underlying the amplifying or priming effects of glucagon upon insulin secretion, and more widely alpha cell -> beta cell communication. In doing so, we resolve a debate about whether glucagon amplification of beta cell function occurs in vivo. We have also provided the first framework for how G protein-coupled surface receptors contribute to intercellular paracrine communication in complex tissue such as the pancreatic islets. Intellectual property: During our studies, we discovered a novel alpha cell-secreted regulator of GLP1R. As such, we have generated a significant intellectual property portfolio surrounding diabetes therapy, which we are currently extending into preclinical models with a view to spinning out a company that can take this potentially novel GLP1R therapeutic forward with appropriate investment. Reputation: Our well-validated GLP1R/GIPR probes have been widely validated and distributed through Europe, North America and Asia, with knock-on effects for the UK's reputation in incretin biology |
| First Year Of Impact | 2024 |
| Sector | Healthcare,Pharmaceuticals and Medical Biotechnology |
| Impact Types | Societal Economic |
| Description | GC-globulin as a novel regulator of alpha cell function and glucagon secretion during type 2 diabetes |
| Amount | £249,086 (GBP) |
| Organisation | Diabetes UK |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 05/2023 |
| End | 05/2026 |
| Description | Steve Morgan Foundation-Diabetes UK Grand Challenge |
| Amount | £2,546,826 (GBP) |
| Funding ID | 23/0006627 |
| Organisation | Diabetes UK |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 03/2024 |
| End | 03/2029 |
| Title | Chemical probes for the detection and visualization of GIPR |
| Description | We developed the GIPR probes and are testing their specificity in pancreatic islets. Our partners (Frank Reimann and Fiona Gribble) are testing the ligands in the brain. We recently filed a European patent to protect intellectual property surrounding these probes, and will look to commercialize going forward. |
| Type Of Material | Technology assay or reagent |
| Year Produced | 2023 |
| Provided To Others? | Yes |
| Impact | There is no specific antibody for GIPR, which is holding back understanding of sites of action of this important therapeutic receptor. |
| Title | Chemical probes for the detection and visualization of tirzepatide targets (2024) |
| Description | Fluorescently labelled tirzepatide to delineate target GLP1R/GIPR binding sites in the periphery and brain, which might underlie effects of the drug on glucose homeostasis and food intake. |
| Type Of Material | Technology assay or reagent |
| Year Produced | 2023 |
| Provided To Others? | No |
| Impact | Tirzepatide is a major new drug therapy for type 2 diabetes and obesity. The cells/neurons that tirzepatide binds to exert its biological effects are unknown, in part due to unreliable antibodies for GLP1R/GIPR. Fluorescently-labelled tirzepatide is thus very timely for the field, allowing us to understand how this drug distributes in the body. |
| Description | Development and testing of GIPR probes |
| Organisation | University of Cambridge |
| Department | Institute of Metabolic Science (IMS) |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We have developed GIPR probes. No antibody exists for this GPCR, which is becoming translationally very relevant, since it is targeted by GLP1R/GIPR dual agonists for the treatment of diabetes and obesity. |
| Collaborator Contribution | We developed the GIPR probes and are testing their specificity in pancreatic islets. Our partners (Frank Reimann and Fiona Gribble) are testing the ligands in the brain. We recently filed a European patent to protect intellectual property surrounding these probes, and will look to commercialize going forward. |
| Impact | The partnership is still in its early phase, but we have already filed a patent, have a mansucript under revision with Eli Lilly and University Cambridge. The collaboration is multi-disciplinary spanning chemical biology, neuroscience, and involves an industrial partner (Eli Lilly). |
| Start Year | 2021 |
| Description | Endogenous GPCR clustering analysis |
| Organisation | University of Birmingham |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We collaborated with Prof Dylan Owen's lab to perform dSTORM microscopy, as well as clustering analysis of the ensuing datasets. |
| Collaborator Contribution | Dylan's lab provided free time on an ONI nanoimager system (usually 37 GBP per hr), as well as technical assistance with analysis. |
| Impact | We recently published a manuscript together in Nature Communications, which shows data from the collaboration. https://pubmed.ncbi.nlm.nih.gov/36653347/ |
| Start Year | 2021 |
| Description | Optimization of methods to purify stem cell-derived beta cells |
| Organisation | Novo Nordisk |
| Department | Novo Nordisk Research Centre Oxford |
| Country | United Kingdom |
| Sector | Charity/Non Profit |
| PI Contribution | We discovered that only ~ 50% of stem cell-derived beta cells (SBC) express GLP1R, a mature functional marker. Using our proprietary technology (GLP1R chemical probes), we have devised steps to increase mature SBC yield by sorting according to GLP1R positivity. |
| Collaborator Contribution | Novo Nordisk Research Centre Oxford funded a postdoctoral researcher to conduct the research. They also provide access to their facility, including provision of reagent for production and screening of SBCs. |
| Impact | N/A |
| Start Year | 2023 |
| Description | Purifying mature hESC-derived beta cells using GLP1R probes |
| Organisation | University of British Columbia |
| Country | Canada |
| Sector | Academic/University |
| PI Contribution | We developed and validated GLP1R probes, allowing its visualization. |
| Collaborator Contribution | The partner generated beta-like cells from hESC, before staining with GLP1R probes and FACS-sorting for assessment of maturity. |
| Impact | We have shown that GLP1R can be used to purify the most mature beta-like cells derived from hESC. This is important, since transplants of such cells are in clinical trials, yet performance is still lacking versus native islets. |
| Start Year | 2019 |
| Title | GC-GLOBULIN FOR USE IN TREATING DIABETES |
| Description | The invention relates to GC-globulin, or a variant thereof, for use in treating diabetes. |
| IP Reference | WO2024062254 |
| Protection | Patent / Patent application |
| Year Protection Granted | 2024 |
| Licensed | No |
| Title | PEPTIDE CONJUGATES FOR LABELLING ENDOGENOUS GIPR AND GLP-1R |
| Description | The invention relates to a peptide conjugate comprising a peptide covalently linked to a label, wherein the peptide comprises an amino acid sequence of a protein ligand that binds at least one class B1 G protein-coupled receptor, wherein the peptide is covalently linked to the label. The protein ligand is preferably an agonist, antagonist and/or co-agonist of at least one class B1 G protein-coupled receptor, preferably from the Glucagon-like subfamily. The agonist, antagonist and/or co-agonist is preferably selected from tirzepatide, LY3437943 or GIF. The invention further relates to kits comprising the peptide conjugate according to the invention or means for assembling the conjugate, as well as methods for using the peptide conjugate according to the invention. |
| IP Reference | WO2024133236 |
| Protection | Patent / Patent application |
| Year Protection Granted | 2024 |
| Licensed | Yes |
| Description | BRC Day |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Patients, carers and/or patient groups |
| Results and Impact | 'BRC Day' -A free event for young children and families to engage with scientific activities -widens participation and encourages the idea of science as an accessible career option from a young age |
| Year(s) Of Engagement Activity | 2024 |
| Description | Diabetes UK supporter visit |
| Form Of Engagement Activity | Participation in an open day or visit at my research institution |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Patients, carers and/or patient groups |
| Results and Impact | Diabetes UK site visit for their South East supporter group, including individuals with lived experience. Visitors were provided with an overview of MRC-funded activities, as well as provided with a tour of OCDEM clinical research unit, islet transplantation and research facilities, including hands-on demos. |
| Year(s) Of Engagement Activity | 2023 |
| Description | In2Science Student shadowing |
| Form Of Engagement Activity | Participation in an open day or visit at my research institution |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Schools |
| Results and Impact | In2Science Student shadowing hosts, Aug 2023 and Aug 2024 -Shadowing scheme aimed at students from underrepresented backgrounds in science -First-hand experience of research and access to a scientific mentor that can answer questions about next steps in academia |
| Year(s) Of Engagement Activity | 2024 |
| Description | Oxford Science and Ideas Festival |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Public/other audiences |
| Results and Impact | The lab participated in the Oxford Science Festival, on behalf of the Radcliffe Department of Medicine. We set up a stall with hands-on demo relevant to diabetes/obesity. |
| Year(s) Of Engagement Activity | 2023 |
| URL | https://if-oxford.com/events/ |
| Description | Oxford Science and Ideas Festival |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Patients, carers and/or patient groups |
| Results and Impact | 'Your cells and sugar' stand at IF Oxford, Oct 2024 -A free event for young children and families to engage with scienctific activities -widens participation and encourages the idea of science as an accessible career option from a young age |
| Year(s) Of Engagement Activity | 2024 |
| Description | Winchester diabetes support group seminar |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Patients, carers and/or patient groups |
| Results and Impact | Winchester diabetes support group seminar 'Shedding light on insulin: microscopy tools in research', Sep 16 2024 -Questions from individuals living with both type 1 and type 2 diabetes -An opportunity to share information about current research tools being exploited in our lab |
| Year(s) Of Engagement Activity | 2024 |
| Description | Women supporting STEM |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Postgraduate students |
| Results and Impact | Organised a 'Women supporting STEM' panel within the department, Feb 2024 -Celebrating not just researchers but support staff who facilitate research -Widened discussions about inclusivity and diversity in the department |
| Year(s) Of Engagement Activity | 2024 |