Supervisor View Full Details 2nd

• genetics, genomics and molecular biology
• infectious disease and the immune system

• Ophthalmology

• Immunology
• Other

Ophthalmic surgery, ophthalmology

Our group successfully operates within a clinician-scientist framework, being uniquely positioned within RCSI and the Royal Victoria Eye and Ear Hospital to investigate the immunological components of a range of inflammatory eye diseases. The clinical lead, Prof. Conor Murphy has established research interests in the areas of corneal transplantation and ocular surface/dry eye disease (DED).

We are currently focusing on targeting ocular surface inflammation in the autoimmune disease Sjogren's Syndrome (SS), which gives rise to dry eyes and dry mouth through reduced exocrine gland function, as well as inflammation at multiple extra-glandular sites. Therapeutic options for SS are limited, as are diagnostic tests that allow identification of patients who will go on to develop further complications. Recently, microRNA species (miRs) have been shown to regulate inflammation, suggesting that micro-RNA based strategies hold therapeutic potential in DED. We have optimised a novel technique for the isolation of miRs from human conjunctival epithelial cells (CEC) using impression cytology. Building upon this we are developing novel microRNA-based therapeutics for topical delivery to the ocular surface aimed at reducing ocular surface inflammation and ameliorating disease symptoms. This model will also be applied to other important external eye diseases including GVHD and Stevens Johnson syndrome.

While recent studies have linked alterations in miR expression profiles in pSS patients to reduced exocrine gland function, none have specifically (a) identified the targets for these miRs or (b) demonstrated a relationship between miR expression and over-production of pathogenic cytokines. Our preliminary findings strongly indicate that peripheral blood cells in pSS patients are primed to over produce inflammatory cytokines as a result of altered miR expression. Additionally altered miR expression in CEC may play a role in initiation and perpetuation of inflammation and development of DED in pSS patients. Our hypothesis is that a specific panel of miRs that we have identified to be dysregulated in SS patients cells may contribute to pSS pathology and that therapeutic manipulation of these miRs may ameliorate the course of the disease.

Clinical program:
Patients with pSS will be recruited from the cornea clinics of RVEEH and the connective tissue disease clinics at St Vincent's University Hospital.

Scientific program:
- Expression levels of our panel of miRs and their putative gene targets in peripheral blood and CECs from patients and healthy controls will be assessed in previously bio-banked samples.
- Direct gene targets will be determined by transfecting biotinylated miRs into CECs and following pull-down from the cytosolic fraction, bound transcripts will be identified by RNA Seq. These miRs and mRNA targets will be then validated by quantitative qPCR.
- Inflammatory cytokine production will be determined by multiplex ELISA in serum and tears and correlated with miRs and gene targets.
- Enhancing or inhibiting the function of key miRs will be performed by transient transfection of miR mimics or antagomiRs.
- Expanding on our previous work in drug development in this area, novel nanoparticle-based therapeutics will be designed for topical delivery to the eye in order to target pro-inflammatory cytokine expression at the ocular surface.