title: Gout Biosensor: Towards the development of a peptide-based diagnostic for crystal arthropathies and Amplifying Graduate Student Perspectives on Supervision and Satisfaction at the University of Calgary
Creators: name: Butler, Tanille Marya
Publisher: name: Graduate Studies
Year: 2024
Subjects: subject: Crystal Arthropathies
subject: Monosodium Urate (MSU) Crystals
subject: Calcium Pyrophosphate Dihydrate Crystals (CPPD)
subject: Peptide-Crystal Binding
subject: Peptide-Based Detection
subject: Fluorescence
subject: Microscopy
subject: Computational Modelling
subject: Flow Cytometry
subject: Graduate Student Perspectives
subject: Graduate Student Experience
subject: Graduate Student–Supervisor Relationship
subject: Biochemistry
subject: Chemistry--Physical

description: This thesis primarily investigates the use of fluorescently labelled crystal-targeting peptides to develop a gout biosensor to improve the diagnostics of crystal arthropathies. Additionally, Chapter 7 examines survey responses from a secondary research project exploring graduate student experiences related to supervision and satisfaction within NSERC disciplines at the University of Calgary. With the growing prevalence of gout, there is an increasing need for accurate, cost-effective, and automated diagnostic methods to distinguish between monosodium urate (MSU) crystals, which cause gout, and calcium pyrophosphate dihydrate (CPPD) crystals, responsible for pseudogout. The current gold-standard diagnostic approach, compensated polarized light microscopy, is limited by its dependence on operator skill and lack of automation. To address these challenges, the study employed a multifaceted strategy involving phage display, peptide synthesis, microscopy, flow cytometry, and computational modelling to identify peptides capable of differentiating between MSU and CPPD crystals. Initial phage display efforts were hindered by high background binding of the phage, leading to the unexpected discovery of an interaction between MSU crystals and the major coat protein of the bacteriophage. This finding laid the groundwork for enhancing peptide binding to MSU crystals. While the identified peptides demonstrated strong binding to MSU crystals, specificity remained a challenge due to similar binding observed with CPPD crystals. An Alizarin Red S counterstain was introduced to improve differentiation, distinguishing CPPD crystals without affecting MSU crystals in microscopy studies. However, when flow cytometry was explored as a high-throughput tool, we encountered challenges with dye compatibility. Although 84% accuracy was achieved in classifying individual crystals through logistic regression of peptide-bound crystal data, issues with dye stability and clinical sample complexity indicate further refinement is needed before clinical implementation. The second project focused on graduate students' supervisory and program experiences in NSERC disciplines at the University of Calgary. Data from the 2022 and 2023 Graduate Student Experience Surveys indicated overall satisfaction with supervisory support and communication but highlighted ongoing issues with inadequate funding and mental health challenges despite available institutional resources. These findings highlight areas where enhanced supervisor support and training could better meet evolving student needs.