MBLEX defs:U5: Cells, Tissues, Cancer

Adaptive immunity

Synonymous with specific immunity referring to the body's ability to remember, recognize, and respond to certain harmful substances or bacteria.

Allergen

An antigen that triggers an allergic response.

Allergic reaction

A hypersensitivity disorder of the immune system where normally harmless substances are treated as if they are dangerous. Allergic reactions can be mild to moderate with symptoms that include red and itchy eyes, runny nose, eczema, hives, an asthma attack, or anaphylaxis, which can interfere with breathing and is potentially life-threatening.

Antibodies

Plasma protein released by plasma B cells that can bind with an antigen to neutralize or kill it; also called immunoglobulin.

Antigen

A harmful substance that causes the body to produce antibodies.

Autoimmune diseases

Any disease characterized by the immune system attacking the body's own tissues.

Autoimmunity

A condition in which the body produces an immune response against its own tissue constituents.

B cells

Specialized white blood cells involved in antibody-mediated immunity.

Cervical nodes

Lymph nodes in the neck.

Hypersensitivity

An excessive and inappropriate response of the immune system.

Immune system

Components from different body systems that work together to protect the body from disease and disorder.

Inflammatory response

A nonspecific immune response to injury or tissue damage causing the movement of white blood cells to an area and resulting in redness, pain, heat, and swelling.

Inguinal nodes

Lymph nodes in the inguinal (groin) region.

Lymphocyte

A type of white blood cell that is part of the immune system. There are two main types of lymphocytes: B cells (that destroy particular bacteria, viruses, and chemical toxins) and T cells (that do not secrete antibodies but instead, directly attack bacteria or cancerous cells).

Macrophage

Another type of white blood cell that works with lymphocytes in the immune system.

Mechanical barriers

Natural barriers, like the skin and mucous membranes, that prevent entry to the body by bacteria or other substances.

Memory cells

A lymphocyte that tracks microorganisms encountered by the body.

Monocytes

A large, phagocytic leukocyte that circulates to provide immune protection and constitutes from 3-8% of white blood cells in humans.

Neutrophils

A type of white blood cell that protects the body from invading microorganisms through phagocytosis.

Nonspecific immunity

Also called innate immunity, this is the defense system with which humans are born. It is not targeted at a specific agent but rather provides the first line of defense in an immune response through the skin barrier, through enzymes in tears and skin oil, through mucus which traps bacteria, and through stomach acid.

Peyer's patches

The lymphoid tissue located in the submucosa of the intestines.

Phagocyte

White blood cells that digest foreign or dead organisms.

Phagocytosis

The process performed by a phagocyte whereby an invading microorganism is taken into the cell body and digested.

Specific immunity

Immune response targeted at a specific infectious agent (also called adaptive immunity).

T cells

A type of lymphocyte that plays a key role in cell-mediated immunity.

Thymus gland

A specialized organ of the immune system that secretes the hormone thymosin, which promotes the maturation of T lymphocytes.

Tonsils

Lymphoid tissue in the pharyngeal region that aids with immune function in the mouth.