Various Types of Biological Immunity

Description: Humoral immunity is a biological defense against infection and disease mediated by antibodies. Antibodies are proteins produced by B cells in response to antigens, proteins on the surface of infectious particles. This type of immunity takes time to develop in an immune response. Antibody production can be either naturally or artificially stimulated.

Description: Cell-mediated immunity is a biological defense against infection and disease mediated by T cells, NK cells, and macrophages. The release of various chemicals, called cytokines, is responsible for the initial response to foreign particles. Cell-mediated immunity is responsible for initiating humoral immunity.

Description: Innate immunity is a biological defense against infection and disease present prior to infection. Immune cells that circulate at all time, including macrophages and dendritic cells, respond to foreign material in a nonspecific manner. In the absence of memory cells, innate immunity is necessary to initiating the immune response in the event of infection.

Description: Adaptive immunity is a specific biological defense against infection and disease that is acquired after contact with infectious agents. It can be stimulated both naturally and artificially. Many types of immune cells or components take part in the adaptive response including B cells, T cells, and antibodies. They respond to antigens, specific proteins, on the surface of infectious agents in a specific manner.

Description: Passive immunity is a biological defense against infection and disease mediated by immune components obtained from another individual. The response is often short-lived, lasting only a few months. Antibodies can be artificially obtained by injection or naturally by a fetus or breastfed child from its mother. Cell-mediated immunity can also be passively obtained by the transfer of histocompatible activated T-cells.

Description: Active immunity is a long-term biological defense against infection and disease mediated by memory immune cells. It can last a lifetime. Though it takes time to develop, the adaptive response, with both B and T cells, can become activated by contact with infectious agents to react to further infections immediately. Active immunity can be induced artificially by vaccination.

Description: Natural immunity is a biological defense that occurs in response to exposure to infectious agents. It is due to unintentional contact with the disease causing agents. Natural immunity protects an individual against infection and disease specific to the agent to which they have been exposed.

Description: Artificial immunity is a biological defense that occurs in response to exposure to infectious agents. It is induced by deliberate actions such as vaccination or serum antibody injections. Artificial immunity protects an individual against infection and disease specific to the agent to which they have been exposed.