text: Cuts and wounds in the skin heal in much the same way as a zip being fastened, new microscopic images have revealed. Biologists have studied the healing process at a molecular level using electron microscopes to examine skin as it repairs itself. They found skin cells appear to attach to each other using tiny tubes that then pull them together so they interlock like a zip. This image on the left taken of skin cells healing a wound using an electron microscope show how cells on opposing sides (coloured green and brown) interlock together in a similar way to a zipper used on clothes. The image on the right shows how the would looks on the surface at this stage in the healing process . The researchers hope their findings could help in the development of new treatments for wounds that could speed up this process. Dr Mikhail Eltsov, one of the scientists behind the study at Goethe University Frankfurt, Germany, said: 'When we look at it from a distance, it appears as if skin cells simply fuse to each other, but if we zoom in, it becomes clear that membranes, molecular machines, and other cellular components are involved. 'Our electron microscope allows us to distinguish the molecular components in the cell that act like small machines to fuse the skin. 'In order to visualize this orchestra of healing, a very high-resolution picture of the process is needed. 'For this purpose we have recorded an enormous amount of data that surpasses all previous studies of this kind.' Dr Eltsov and his colleagues used cells from fruit fly embryos to study the healing processes that take place in skin. The study, which is published in the journal Nature Cell Biology, found that the skin cells on either side of the wound begin by 'sniffing' each other out to find their opposing partners. They then develop adhesive like structure made of microscopic tubes, called microtubules, that pulls them closer together. These attachments work a like velcro and pulls the skin cells towards the opening. Once the cells meet, they use these microtubules as a scaffolding to interlock together like a zip. Professor Achilleas Frangakis, a microscopy expert at Goethe University Frankfurt who led the study, said: 'What was also amazing was the tremendous plasticity of the membranes in this process which managed to close the skin opening in a very short space of time. 'When five to ten cells have found their respective neighbors, the skin already appears normal.' Skin taken from the dead could soon be used to treat wounds in the living. Researchers have found that skin taken from cadavers that is stripped of its cells is effective in healing acute wounds, such as burns, as well as painful ulcers. They believe the new treatment could be used to treat wounds that do not easily heal by themselves, which cost the US alone more than $25 billion (£17 billion) a year. The scientists stripped out the skin’s inner layer – the dermis – which contains blood vessels, nerve endings, hair follicles and sweat glands, to leave behind its matrix of proteins. The team discovered that ‘decellulised’ skin provides a scaffold that the recipients own cells can populate and can effectively treat acute wounds, such as burns. Clothing zips, like the one above, hold fast by using interlocking segments and this is how skin closes a wound .
target: Biologists at Goethe University Frankfurt, Germany, studied skin healing in fruit fly embryos using an electron microscope to watch what happened .
  Skin cells use microscopic tubes to pull towards each other and interlock .
  Researchers hope it may help develop new treatments to speed up healing .