TY - CHAP M1 - Book, Section TI - Overview of Immunity A1 - Levinson, Warren A1 - Chin-Hong, Peter A1 - Joyce, Elizabeth A. A1 - Nussbaum, Jesse A1 - Schwartz, Brian PY - 2020 T2 - Review of Medical Microbiology & Immunology: A Guide to Clinical Infectious Diseases, 16e AB - The main function of the immune system is to prevent or limit infections due to viruses, bacteria, fungi, protozoa, and worms. The first line of defense against microorganisms is the barrier formed by intact skin and mucous membranes. If microorganisms breach this line and enter the body, then a second line of defense is available to rapidly detect foreign material and destroy any harmful agents. These components of the immune system are preformed and encoded in the genome, and therefore, this arm of host defense is called innate immunity (Table 57–1). Innate immunity works immediately upon the first encounter with a microorganism. The innate arm is nonspecific in that it can recognize patterns shared among many microorganisms (described in more detail in Chapter 58). For example, a neutrophil can sense, ingest, and destroy many different kinds of bacteria by exploiting features common among bacterial cells. SN - PB - McGraw Hill CY - New York, NY Y2 - 2024/03/29 UR - accessmedicine.mhmedical.com/content.aspx?aid=1175826648 ER -