Lymphatic Terminology

Lymphatic system

A network involved in fluid balance, immune defense, and lymph transport.

Lymph

Liquid carried through lymphatic vessels containing immune cells.

Lymphatic vessel

A vessel that transports lymph.

Lymph node

A small immune organ that filters lymph and contains immune cells.

Spleen

Organ that filters blood, removes old blood cells, and participates in immune responses.

Thymus

Organ where T lymphocytes mature.

Tonsils

Lymphatic tissues that help defend against pathogens entering through the mouth and nose.

Innate immunity

The body's immediate, nonspecific defense against pathogens.

Adaptive immunity

Specific immune defense involving lymphocytes and immune memory.

Antigen

A substance recognized by the immune system.

Antibody

A protein produced by B cells/plasma cells that binds a specific antigen.

B cell

A lymphocyte responsible for antibody-mediated immunity.

T cell

A lymphocyte involved in cell-mediated immunity and immune regulation.

Helper T cell

A T cell that coordinates immune responses.

Cytotoxic T cell

A T cell that kills infected or abnormal cells.

Macrophage

A phagocytic immune cell that engulfs pathogens and debris.

Neutrophil

A white blood cell important in rapid responses to bacterial infection.

Inflammation

A protective immune response involving redness, heat, swelling, pain, and altered function.

Phagocytosis

The process of engulfing and destroying pathogens or particles.

Immunity

The body's ability to resist or fight a particular pathogen or threat.

Autoimmune disease

A disease in which the immune system attacks the body's own tissues.

Immunodeficiency

A condition in which immune function is weakened or absent.

Allergy

An exaggerated immune response to a normally harmless substance.

Anaphylaxis

A severe, rapid allergic reaction involving multiple body systems.

Lymphedema

Swelling caused by impaired lymphatic drainage.

Lymphadenopathy

Abnormal enlargement of lymph nodes.

HIV

Human immunodeficiency virus that attacks immune cells, especially CD4 T cells.

AIDS

Advanced HIV infection involving severe immune system damage.

Sepsis

Life-threatening organ dysfunction caused by a dysregulated response to infection.

Opportunistic infection

An infection occurring more easily when immune defenses are weakened.

Vaccine

A preparation that trains the immune system to recognize a pathogen or antigen.

Immunization

The process of becoming protected against a disease.