5.3 Clonal Selection

antigen exposure

B and T cells require this to become activated

clonal selection

B and T cells specific to a certain antigen are "selected" and activated by exposure to that antigen.

adulthood

By this time you thymus has already produced and sent out all of the T cells it will ever make

lymphatic system

Network of vessels, ducts, nodes, and organs that collects fluid that leaks from tissues and screens it for pathogens before returning it to the blood stream.

Phagocytosis

Pathogens or antigens covered with antibodies will be "eaten" by phagocytic cells through

clonal expansion

Rapid cell division of specific B or T cells after "selection"/activation by a specific antigen.

Antibodies

Specificity of B cells comes from the variable region of their

TCRs

Specificity of T cells comes from their (T Cell Receptors)

Thymus

T cells mature here before migrating to the lymph node to hang out and wait for possible pathogen exposure. This organ is at 1st largest in babies and shrinks throughout life.

Neutralization

antibodies bind to pathogen surface proteins preventing infection of a host cell

Complement

antibodies bound to these innate immune system proteins target them to infected cells for lysis

Agglutination

antibodies cause antigens/pathogens to clump together

gene rearrangement

process in developing B and T cells that results in offspring cells with billions of slightly different antibody or T cell receptor structures

lymph nodes

small oval clumps of lymphatic tissue throughout the body where B and T cells encounter APCs and pathogens as they flow through.

mitosis

type of cell division that B and T cells do during clonal expansion.