Chapter 11 Immunology

memory cell

general term for a lymphocyte that is responsible for the phenomenon of immunological memory.

secondary immune response

the adaptive immune response provoked by a second exposure to an antigen. It differs from the primary response by starting sooner and building more quickly, and is due to the presence of long-lived memory B cells and T cells specific for the antigen.

vaccination

the deliberate induction of protective immunity to a pathogen by the administration of killed or nonpathogenic forms of the pathogen or its antigens to induce an immune response.

protective immunity

the specific immunological resistance to a pathogen that is present in an individual during months after either vaccination or recovery from an infection with the pathogen, and which is due to pathogen-specific antibodies and effector T cells produced during the primary response.

immunization

the deliberate provocation of an adaptive immune response by introducing antigen into the body.

memory CD4 T cell

type of long-lived CD4 T cell that is produced from activated T cells during the primary response to an antigen. On subsequent exposure to their specific antigen, memory CD4 T cells are activated to differentiate into effector CD4 T cells as part of the secondary and subsequent immune responses to that antigen.

memory CD8 T cell

type of long-lived CD8 T cell that is produced from activated T cells during the primary response to an antigen. On subsequent exposure to their specific antigen, memory CD8 T cells are activated to differentiate into cytotoxic CD8 T cells as part of the secondary and subsequent immune responses to that antigen.

long-lived plasma cell

type of plasma cell produced toward the end of an adaptive immune response that can last a lifetime, producing a steady level of protective antibody. They reside in the bone marrow.

hemolytic anemia of the newborn

a potentially fatal disease caused by maternal IgG antibodies directed toward paternal antigens expressed on fetal red blood cells. The usual target of this response is the RhD blood group antigen. Maternal anti-RhD IgG antibodies cross the placenta to attack the fetal red blood cells. Also known as erythroblastosis fetalis.

Rhesus D (RhD)

blood group antigen belonging to the Rhesus group. It must be matched for successful blood transfusion. RhD mismatch between fetus and mother is the cause of hemolytic anemia of the newborn.

serological memory

immunological memory maintained by long-lived plasma cells, an archive of plasma cells representing a person's history of response to infection and vaccination.

autophagy

the degradation of a cell's own components in its lysosomes, enabling cellular building blocks to be reused. It is a mechanism of cell maintenance.

metabolic reprogramming

the change from catabolic to anabolic metabolism that occurs when a naive T cell is activated by antigen.

asymmetric division

a cell division that produces two daughter cells that are unlike each other in some way; for example, one may be smaller than the other or one may contain a different complement of cytoplasmic proteins than the other.

central memory T cell (TCM cell)

one of two subsets of circulating memory T cells (the other being effector memory T cells) that are distinguished by different activation requirements. Central memory T cells have a preference for the T-cell zones of secondary lymphoid tissues and take longer than effector memory T cells to mature into functioning effector T cells after encounter with their specific antigen.

resident memory T cells (TRM cells)

long-lived memory T cells produced during an adaptive immune response that enter the infected non-lymphoid tissue and reside there, never to return to the circulation.

effector memory T cells (TEM cells)

shorter-lived memory T cells produced during an adaptive immune response that circulate between the blood and peripheral tissues, providing rapid effector functions upon re-exposure to antigen.

variola

name given to both the smallpox virus and the disease it causes: smallpox.

variolation

historical procedure for immunization against smallpox in which a small amount of live smallpox virus was introduced through scarification of the skin.

vaccinia virus

a close relative of the cowpox virus. It causes a limited infection in humans that leads to immunity to the human smallpox virus. Was used as the vaccine against smallpox that led to eradication of the disease.

killed virus vaccine

a vaccine containing viral particles that have been deliberately killed by heat, chemicals, or radiation. Also called inactivated virus vaccine.

live-attenuated virus vaccine

a vaccine composed of live virus particles that have an accumulation of mutations that impede their growth in human cells and capacity to cause disease.

subunit vaccine

a vaccine composed only of isolated antigenic components of a pathogen and not the pathogen itself, either alive or dead.