Yong Loo Lin School of Medicine

4 ARTICLES PUBLISHED IN JoVE

Immunology and Infection

Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases

Song Buck Tay^1,3, Jeng Yeong Chow², Maybelle Kho Go^1,3, Wen Shan Yew^1,3

¹Department of Biochemistry, Yong Loo Lin School of Medicine, ²Department of Chemistry, University of Utah, ³Synthetic Biology Research Consortium, National University of Singapore

Quorum-quenching enzymes are anti-virulent and anti-bacterial options that can mitigate pathogenesis without risk of incurring resistance, by preventing the expression of virulence factors and genes associated with antibiotic resistance and biofilm formation. In this study, we report a method that demonstrates the efficacy of quorum-quenching enzymes in bacterial biofilm disruption.

Immunology and Infection

A Non-invasive Way to Isolate and Phenotype Cells from the Conjunctiva

Tanima Bose¹, Aihua Hou², Ryan Lee², Louis Tong^2,3,4,5, K. George Chandy¹

¹Lee Kong Chian School of Medicine, Nanyang Technological University, ²Singapore Eye Research Institute, ³Singapore National Eye Center, ⁴Duke-NUS Medical School, ⁵Yong Loo Lin School of Medicine

The exposed normal ocular surface consists of cornea and conjunctiva. Epithelial cells, goblet cells and immune cells are present in the conjunctiva. Here, a non-invasive, technique of impression cytology is described using an impression cytology device and flow cytometry to analyze immune cells in the conjunctiva.

Immunology and Infection

A Chronic Autoimmune Dry Eye Rat Model with Increase in Effector Memory T Cells in Eyeball Tissue

Aihua Hou^1,2, Tanima Bose³, K. George Chandy³, Louis Tong^1,2,4,5

¹Singapore Eye Research Insitute, A Member of SingHealth, ²DUKE-National University of Singapore Medical School, ³Lee Kong Chian School of Medicine, Nanyang Technological University, ⁴Singapore National Eye Center, ⁵Yong Loo Lin School of Medicine, National University of Singapore

This report describes a method to induce chronic experimental autoimmune dry eye in Lewis rats through immunization with an emulsion of rat lacrimal gland extract, ovalbumin, and complete Freund's adjuvant, followed by the injection of lacrimal gland extract and ovalbumin into the forniceal subconjunctiva and lacrimal glands six weeks later.

Immunology and Infection

Bead Based Multiplex Assay for Analysis of Tear Cytokine Profiles

Praveen Kumar Balne^1,2, Veonice Bijin AU³, Louis Tong², Arkasubhra Ghosh⁴, Mukesh Agrawal⁵, John Connolly³, Rupesh Agrawal¹

¹National Healthcare Group Eye Institute, Tan Tock Seng Hospital, ²Singapore Eye Research Institute (SERI), ³Institute of Molecular and Cell Biology, A*STAR, ⁴GROW Research Laboratory, Narayana Nethralaya Foundation, ⁵Vimta Labs Limited

Analysis of tear film cytokines helps in studying various ocular diseases. Bead based multiplex assays are simple and sensitive and enable the testing of multiple targets in samples with small volumes. Here we describe a protocol for tear film cytokine profiling a using bead based multiplex assay.