Written by Anthony Lewis
“Tears aren’t just an outlet for when our emotional cup overflows, they play a crucial role in protecting our rather exposed eyes. For example, tear fluid has long been known to restrict the activity of Pseudomonas aeruginosa – a bacterium known for its antibiotic resistance that can cause problems from hot tub folliculitis to sight-threatening diseases. To find out how exactly it helps, researchers compared P. aeruginosa’s behaviour in a normal environment (left) to when in contact with tear fluid (right), and found that its motility was greatly impaired. Dark blue shows slow bacterial movement while light green and yellow shows rapid. A protein in tears called DMBT1 slows bacteria by interfering with their ‘twitching’ ability. This halts their spread across the eye, limiting the impact of infection. Understanding this shows how our bodily fluids fight infection, and could point to new medical approaches.”
Read more about this topic in PLOS Pathogens.
About the Fleiszig-Evans Lab
Our epithelial surfaces are normally resistant to infection. Therefore, researchers who study infectious disease commonly use of models that deliberately compromise the target tissue (or otherwise bypass barriers) so that disease can be enabled and studied. These infection models have led to a plethora of important information about factors involved in pathology and/or its resolution when disease is initiated. However, other models are needed to study barriers to infection, or early events that occur prior to disease initiation when it occurs in the absence of overt injury.
In our laboratory, we have developed novel in vivo and in vitro methods for studying defenses during health using the eye and the opportunistic bacterium Pseudomonas aeruginosa as models. We have also advanced imaging technologies that enable us to see into the living epithelium to observe what bacteria do and how the tissue responds in either resistant or susceptible states. Using these methods, and employing array/knockout/knockdown technologies, we have identified specific factors that modulate the ability of bacteria to penetrate the ocular surface epithelium. The data show that pathogen recognition systems are involved in resistance, and suggest that bacterial adaptation in vivo contributes to pathogenesis. Studies aimed at understanding early interactions between microbes and the ocular surface prior to disease initiation have potential for development of novel methods to prevent (rather than simply treat) infection of the eye or other sites.Feliszig-Evans Lab Website
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences (the new name for the MRC Clinical Sciences Centre) the website aims to engage everyone, young and old, in the wonders of biomedicine.
Image originally published under a Creative Commons Licence (BY 4.0)
Published in PLOS Pathogens, May 2017