Physiology
Immunity from disease is actually conferred by two
cooperative defense systems, called: nonspecific, innate immunity and specific, acquired immunity.
Nonspecific protective mechanisms:
repel all microorganisms equally
-Phagocytosis
One common way your immune system destroys antigens is by phagocytosis. Phagocytosis is the process of engulfing (or “eating”) antigens and releasing enzymes that break down the foreign agent. Some phagocytes, like macrophages, constantly circulate throughout your body, while others remain stationary in certain organs, waiting to be activated.
Specific immune responses: are tailored to particular types of invaders.
Immune Response
When an antigen makes it past your skin, which is your body’s first line of defense, it will be met with a comprehensive attack. First, macrophages recognize the pathogen, engulf it, and secrete chemicals that tell helper T cells to prepare for action. Helper T cells recognize the invader’s shape and chemical signal, and summon other immune cells, like killer T cells and B cells, into action. Killer T cells attack and destroy the antigen, while B cells make antibodies against the invader.