What proteins prevent step A infections in wounded skin?

Cathelicidins are essential proteins that play a crucial role in the immune response, particularly in skin defense mechanisms against infections. When skin is wounded, cathelicidins are produced by keratinocytes and certain immune cells, and they exhibit antibacterial properties. These proteins help to disrupt the membranes of bacteria and other pathogens, effectively preventing infections from taking hold in compromised skin.

In contrast, antibodies and antigens are primarily involved in the adaptive immune response rather than directly preventing infections at the site of wounds. Antibodies target specific pathogens that the immune system has encountered before, while antigens are substances that trigger an immune response. Histamines, on the other hand, are involved in inflammatory responses and allergic reactions rather than directly combating infections. Thus, cathelicidins are the most relevant proteins for preventing infections like those seen in step A of wound healing.