• Question: How does a cut heal?

    Asked by nataliejb to Daphne, Darren, Jon, Katherine on 21 Mar 2012.
    • Photo: Darren Logan

      Darren Logan answered on 21 Mar 2012:

      Wound healing is divided into four stages.

      First comes blood clotting, this is to stop you bleeding to death through the cut. Special blood cells called platelets come together at the cut site to form a clot.

      Next comes the inflammatory response. During this stage, bacteria and debris are eaten up by special immune cells and signals are released that cause the cells that will repair the cut to start to grow.

      The proliferative stage is the most complex, it involves new blood vessels to grow to feed the new cells around the wound, while the cells of your skin start to increase in number to fill in the hole, other cells crawl towards the cut to create new skin and they all begin to orientate themselves into position, ready for…

      Contraction. In this stage the cut is made smaller by the action of special cells called “myofibroblasts”. These get a grip on the edges of the cut and contract, pulling the two edges together a bit like how your muscle cells do when you flex them.

      When all the special cells have finished their job and the cut has been closed, they commit suicide (through a process called apoptosis).

    • Photo: Katherine Haxton

      Katherine Haxton answered on 22 Mar 2012:

      The inflammatory response is really important because without it the wound might become infected. If too many bacteria get into a wound, the immune cells may not be enough to deal with it. This can interfere with healing. You can help the process by making sure you wash any cuts, using an antiseptic of some sort, then keeping the wound clean and dry. Some plasters are designed to release antibacterial substances to help prevent infection.
      Some scientists are looking in to wound dressings (plasters and bandages) that can release things to speed up the healing process. This might be antibacterial chemicals; things to encourage the new blood vessels to grow like the gas nitric oxide, NO; and other chemicals that help promote cell proliferation. This would be really useful for very large cuts and other injuries like burns.