A Versatile Group of Molecules, Can Defensins Make an Impact in Medicine?

Abstract: Antimicrobial peptides are an ancient form of innate defense and is present in all ways of life. In humans they are present as cathelicidins and defensins. Both are important for the immune system and they exhibit activity against viruses, bacteria and fungi. Defensins exhibit less cytotoxicity and are better characterized and are thus more easily developed as therapeutic tools. Defensins are apt at doing a multitude of things, from inhibiting Herpes simplex virus replication and preventing anthrax’ lethality to helping with wound closure and acting as biomarkers for a variety of ailments. Defensins have consistently shown good results in a laboratory setting but have less than exemplary in vivo results. Defensins’ multifunctionality as well as the complex environment in living organisms makes characterizing why defensins are not performing as well in vivo difficult. They can also exhibit negative side-effects such as increasing the infectivity of the HIV and inhibiting anti-viral molecules of the innate immune system. Nevertheless, they exhibit big potential as complementary drugs, adjuvants, biomarkers, wound treatment and much more. Further characterization and development is absolutely necessary in these times of increasing antibiotic resistance.