Author Interviews, Infections, PLoS / 05.08.2016
Preventing Bacteria From Sticking Would Eliminate Need For Antibiotics
MedicalResearch.com Interview with:
Dr Peter Monk BSc PhD
Faculty Director of International Affairs
Reader in Immunology
Department of Infection, Immunity and Cardiovascular Disease
Sheffield University Medical School
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: The tetraspanin proteins are found on the surface of all mammalian cells. The cell surface is the place where cells 'socialise': they talk to each other to coordinate activities, stick to each other to form tissues and sometimes crawl across each other to get to where they need to go. Tetraspanins have an important job to do in the organisation of the cell surface, amongst other things enabling the formation of 'sticky patches' (tetraspanin-enriched microdomains or TEM) that cause cells to adhere together or provide traction to allow movement. Some bacteria have evolved ways of hijacking the TEM for their own ends, adhering to tightly to these structures so that the normal things that sweep bacteria away (such as blood, sweat and tears!) are no longer effective. At this point, infection begins.
We have found that the TEM can be partly disrupted, by adding small parts of tetraspanins (peptides) to cells. The peptides seem to work by weakening the tetraspanin glue that holds the TEM together and causing the other components that give the 'stickiness' to the TEM to become more spaced out. We use the analogy of Velcro(TM), where the fabric hooks and loops are held together in woven material; loosen the weave and the hooks and loops fall apart, no longer able to engage strongly with the loops in the opposing piece of fabric.
Using reconstructed human skin, we were able to show that the tetraspanin peptides were both safe and effective; they did not affect wound healing in burned skin, but they could lower the bacterial load in the wound by 50%. This would allow the immune system (including the fluid that 'weeps' from wounds) to deal with the remaining bacteria more easily. Unlike conventional antibiotics that tend to kill bacteria, our peptides simply cause them to get washed away, so not invoking the evolutionary selective mechanisms that lead to resistance.
(more…)