Honours is a fourth-year program which gives you the opportunity to draw together your previous science or health science studies and focus your knowledge, skills and intellect on an exciting piece of original research. Honours programs in the Biomedical and Health Sciences areas are open to eligible students who have completed an undergraduate degree.
No 1. Polymicrobial Nature of Disease
Contact Person: Prof Stuart Dashper
Common oral diseases are caused by ecological shifts in the composition of the microbiome of oral bacterial biofilms. These shifts are mediated by consortia of bacteria whose symbiotic relationships enable them to proliferate. These shifts occur before clinically detectable damage has occurred to the host. Our research focuses on the characterisation of the oral microbiome using a range of nextGen sequencing technologies and advanced bioinformatics. We use these technologies to determine prognostic bacterial biomarkers of both oral and systemic diseases and conditions. Early diagnosis has the potential to radically improve the clinical treatment of diseases. Projects are available to characterise the symbiotic interactions that underlie the virulence of the pathogenic oral bacteria Porphyromonas gingivalis and Treponema denticola. These species are the major causative agents of chronic periodontitis and are associated with a range of systemic diseases including atherosclerosis and rheumatoid arthritis. They grow as polymicrobial biofilms and we have shown that they are intimately associated and influence each other’s behaviour. They interact using a range of surface molecules, including adhesins, fimbriae and enzymes and both produce outer membrane vesicles that aid in polymicrobial biofilm development and nutrient acquisition. Techniques to be used to explore their interactions include continuous culture of polymicrobial biofilms, bacterial genetic manipulation, a range of imaging technologies including confocal and electron microscopy, RNAseq, protein expression, metabolomics, proteomics genome sequencing and chemotaxis assays.
No 2. Host-Pathogen Interactions, Antimicrobial Materials, Nanomaterials and Vaccines:
- Mucosal and systemic immune response to bacteria
- Host responses to Outer Membranes Vesicles (OMVs)
- Cytotoxic T cell based vaccine design and development
- Design and development of Antimicrobial Materials
Contact Person: A/Prof Neil O’Brien-Simpson
Our research interests include; (a) the pathogenic synergy between pathogenic and non-pathogenic bacteria and their ability to cause disease and immunopathology, (b) understanding how nanomaterials can be used and designed to aid vaccine development and also be used in the design of antimicrobial materials to target antibiotic resistant organisms.
Projects are available investigating the mucosal and systemic immune responses to single and multi-bacterial species colonization and infection. One project investigating how outer membrane vesicles are used to aid bacterial pathogenicity is novel an exciting area in bacteriology. Projects involving therapeutics include investigating the synthesis of peptides and nanomaterials for the development of novel antimicrobial materials to target a narrow range of pathogenic rather than health-associated bacteria. Finally investigating how biodegradable materials can be used to deliver vaccine antigens to stimulate a CTL response and how chemical moieties affect immunity are offered. These projects will use a number of techniques and in-house equipment such as peptide synthesis, HPLC, FPLC, Mass spectrometry, polymer chemistry, Flow cytometry, ELISPOT, T-cell proliferation, real-time PCR and cytokine DNA microarray.
No 3. Oral Immunity and Cancer
Contact Person: A/Prof Glen Scholz
The mucosal epithelial cells that line the oral cavity play critical roles in protecting us from infection. Important roles include functioning as a physical barrier to prevent infection in the first place, as well as actively participating in microbial surveillance. The barrier function of the mucosal epithelium is maintained through cycles of cell proliferation and differentiation, which are regulated by specific transcription factors, such as IRF6. Importantly, as well as compromising oral immunity, the dysregulation of this process also results in oral cancer. The expression of pathogen-recognition receptors, including protease-activated receptors (PARs), is central to the role of mucosal epithelial cells in activating the immune system in response to microbial pathogens. This commonly involves the production of inflammatory cytokines (e.g. IL-36). Importantly, the dysregulation of this process can result in chronic infection and disease.
The following Honours Projects will be offered in 2018:
Project 1: Regulation of oral immunity by the inflammatory cytokine IL-36.
Project 2: Regulation of oral immunity by protease-activated receptors.
Project 3: Regulation of oral immunity by the IRF6 transcription factor.
Project 4: Tumour suppressor functions of the IRF6 transcription factor. You will gain expertise with in vitro and in vivo experimental systems, and develop practical skills in a multitude of techniques, including mammalian and bacterial cell culture, gene-silencing and gene-editing, real-time PCR, mass spectrometry, flow cytometry, and immunofluorescence confocal microscopy.
You will be based in our student office and laboratories at the Bio21 Institute (http://www.bio21.unimelb.edu.au).
No 4. Towards a Better Understanding of the Specific Role of Poru During Secretion/Conjugation of CTD-Proteins of the T9SS in Pophyromonas gingivalis
Contact Person: Dr Paul Veith
Porphyromonas gingivalis causes chronic periodontitis in humans. The major virulence factors of P. gingivalis are secreted by the novel type 9 secretion system (T9SS). This secretion machinery recognises a conserved C-terminal signal domain (CTD) possessed by secreted proteins. PorU is responsible for CTD cleavage and covalent modification to an outer membrane anchoring anionic carbohydrate (A-LPS). In addition to the central peptidase domain, PorU has two additional domains of unknown function, A and B. This project aims to investigate the proposed functions for these domains by targeting very well conserved regions of sequence within these additional domains and affect major disruption by the insertion of hexa-His tags. PorU mutants will be characterised by assessing the cleavage and A-LPS conjugation status of multiple CTD proteins in membrane and culture fluid fractions. Mutant PorU binding to other ancillary proteins and A-LPS related glycolipid will also be assessed by blue-native PAGE/Western blot. The size difference of PorU observed between the wild-type protein expressed in P. gingivalis and that expressed in Eschericia coli, a species that does not possess a T9SS, will also be investigated.
No 5. Cariology: Novel Preventive Products, Functional Foods, Enhancement of Remineralization
Contact Person: Dr Peiyan Shen
Dental decay, or caries, starts when bacteria in plaque produces an organic acid which dissolves the tooth enamel, breaking down the calcium and phosphate in tooth enamel. Projects are available to test novel products and functional foods designed to assist in the prevention of dental caries and/or dental erosion.
The products may include toothpastes, dental cremes, mouthrinse solutions, gels, and varnishes for topical application. The preventive products will contain anti-caries/erosion agents. Alternatively, commonly consumed foods and beverages will be modified to minimize their potential to cause loss of mineral from teeth such as during dental caries and dental erosion or modified to provide a positive health effect. Projects are available to study the process of enamel remineralization of early tooth decay. Enamel remineralization is the process of net mineral uptake into partially demineralized tooth structure. Projects will study ways of enhancing remineralization and quantify the effects of these treatments using a number of state of the art quantification methods. These projects may include laboratory and/or in situ studies.
No 6. Future Therapeutics: Bioactive Peptides, Natural Inhibitors and Antimicrobial Agents
Contact Person: Dr Laila Huq
From bench to bed-side, multidisciplinary approaches are required to investigate disease prevention and treatment. The oral cavity is a unique environment with diseases and disorders involving the hard tissue of teeth comprising enamel and dentine, soft tissues of the gums, and the protective body fluids saliva and gingival crevicular fluid. Projects are available to study the interactions of the enamel remineralising agent CPP-ACP with enamel, dentine, and saliva at the molecular through to the tissue level. The oral cavity also includes the commensal consortium of bacteria that can become pathogenic. The destructive effects of these oral pathogens are due to cell surface proteases. Projects are available to study the structure-function relationships of natural inhibitors targeted against the bacterial proteases using the state-of the art techniques within microbiology, molecular biology, and protein chemistry. The gene products of these cell surface proteases are translated as large polypeptides with multiple uncharacterised domains adjacent to the catalytic domain. Projects are available to study the roles of these domains and their influence on catalysis. Students will learn various biochemical, biophysical, and analytical techniques and have access to the facilities at Bio21 including the platform technologies of mass spectrometry and advanced microscopy.
Melbourne Dental School Contact
Dr Laila Huq - BSc (Honours) Coordinator
Phone: +61 3 8344 2574 (42574 if calling from a landline phone on campus)
For further information about the course, visit the Honours page.