Adaptive (acquired) immunity refers to antigen-specific defense mechanisms that take several days to become protective and are designed to react with and remove a specific antigen. There are two major branches of the adaptive immune responses: humoral immunity and cell-mediated immunity. Humoral immunity involves the production of antibodies and cell-mediated immunity involves the production of cytotoxic T-lymphocytes, activated macrophages, activated NK cells, and cytokines.
Thumbnail: Anterior view of chest showing location and size of adult thymus. Image used with permission (CC-BY 3.0; )
Dr. Gary Kaiser (COMMUNITY COLLEGE OF BALTIMORE COUNTY, CATONSVILLE CAMPUS)