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Which types of microorganisms can the innate immune system defend against?
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immune system
Stimulation of immune response by activated helper T cells. Activated by complex interaction with molecules on the surface of a macrophage or some other antigen-presenting cell, a helper T cell proliferates into two general subtypes, TH1 and TH2. These in turn stimulate the complex pathways of the cell-mediated immune response and the humoral immune response, respectively.
The innate immune system provides nonspecific protection against a wide variety of potential pathogens. It is designed to defend the body against diverse microorganisms, including:
This system acts as a first line of defense, utilizing physical barriers like the skin, chemical barriers such as antimicrobial proteins, and specialized cells that target foreign invaders or body cells harboring infectious agents. Because these pathogens are highly diverse, the innate immune system's ability to provide a generalized, nonspecific response is essential for maintaining health and repelling most microorganisms before they cause detectable disease.12