How does immune system relate to tissue wound repair

When something, say, cuts your skin, your immune system is immediately alerted of something foreign entering your body. As such, the immune system sends cells to close your wound and try to push out whatever shouldn't be there to keep from dangerous things entering from the new entrance. The same happens when you get a sunburn from your cells rapidly killing themselves off to stop harmful rays from the sun from giving you cancer.

True, using a pedometer can promote a physically active lifestyle.