It is a well-known fact among healthcare professionals that exposed tissue surfaces including skin and mucous membranes are under constant threat of attack from microorganisms in the environment.
It is a particular concern in the eyecare industry, where for many years experts have known that the layer of cells that line these areas, known as epithelial cells, are the first line of defense against these pathogens. However, the underlying molecular mechanisms that allow them to repel microbes were unknown - until now.
According to a study published in the Journal of Clinical Investigation and carried out by researchers at the University of California, Berkeley, light can finally be shed on this area.
The experts have reported that epithelial cells in the cornea, which is highly resistant to bacterial infection, express small antimicrobial peptides, or portions of human cytokeratin 6A, that defend the eye against infection. Through the use of mass spectrometry, study leader Suzanne Fleiszig and colleagues determined that these peptides protect against multiple bacterial pathogens by preventing the bacteria from binding to the epithelial cells.
In addition, the scientists discovered that mice lacking cytokeratin 6A were more susceptible to eye infections.
In an accompanying commentary, Michael Zasloff of Georgetown University School of Medicine also discussed the implications of these findings for the development of antimicorbial therapeutics.