What is the first line of defense against invading bacteria?
Our skin and mucus membranes are the first line of defense against potentially invading bacteria. Their purpose is to keep the bacteria from getting into the body in the first place. Any break or tear in the skin or mucus membranes can allow harmful bacteria or viruses to attack the body. Once inside, macrophages, T-cells, and lymphocytes will be summoned to attack infected body cells and the invading pathogens.