Distinguish between the following:, (a) cell-mediated immunity and humoral immunity, (b) active and passive immunization
A) Cell-mediated immunity is an immune response that does not involve antibodies, but rather involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen. - Humoural immunity is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides. Humoral immunity is so named because it involves substances found in the humour or body fluids.
B) Active Immunity develops after exposure to a disease-causing infectious microorganism or other foreign substance, such as following infection or vaccination.
- Passive Immunity develops after a person receives immune system components, most commonly antibodies, from another person. Passive immunity can occur naturally, such as when an infant receives a mother's antibodies through the placenta or breast milk, or artificially, such as when a person receives antibodies in the form of an injection (gamma globulin injection). Passive immunity provides immediate protection against an antigen but does not provide long-lasting protection.