Inflammation 101: Glossary

Acute Respiratory Distress Syndrome [ARDS]
Life-threatening condition that develops when inflammation and injury to the lungs causes fluid buildup in the airways

Adhesion Molecule
Any of a large number of cell-surface molecules of several different classes that affect the attachment of one cell to another

Antibody
A protein produced by the immune system in response to an antigen, often a virus or bacterium

Arthritis
The inflammation of a joint

Asthma
Chronic condition causing difficulty breathing caused by over-reactive airways

Atherosclerosis
One of many diseases in which fat builds up in the large- and medium-sized arteries, restricting blood flow

Autoimmune Disease
Disorder in which the immune system mistakenly attacks and destroys body tissue that it believes to be foreign

B Cell
A cell produced by the bone marrow that becomes either a memory cell or a plasma cell that forms antibodies against a foreign substance

Bacterium
Tiny, one-celled organism that reproduces by cell division and can be found in virtually any environment

Basophil
Type of white blood cell that contains inflammatory mediators such as histamine

Cancer
Disease caused by the abnormal and uncontrolled division of cells that invade and destroy surrounding body tissues

Chemokine
Molecule that causes white blood cells such as neutrophils and monocytes to move throughout the body (e.g., toward an injury) via the process of chemotaxis

Chemotaxis
Movement of a cell toward or away from a chemical substance

Cholesterol
A fatty substance that higher organisms use in the construction of cell membranes and as an ingredient for making steroid molecules; it is carried through the bloodstream in molecules called lipoproteins

Compensatory Anti-Inflammatory Response Syndrome [CARS]
Condition that develops in some resuscitated injured patients when the body compensates in an effort to stop inflammation

Complement System
Set of molecules in the blood activated by the presence of bacteria, injury or other immune triggers, causing a range of responses associated with starting and maintaining inflammation

COX
Abbreviation for the enzyme cyclooxygenase; the molecular target of nonsteroidal anti-inflammatory drugs (NSAIDs)

COX Inhibitor
Drug that blocks the action of the COX enzyme

C-Reactive Protein [CRP]
Protein not normally found at high levels in the blood of healthy people, but when present it indicates inflammation

Cytokine
Molecule that controls reactions among cells; key component of inflammation

Dermis
Layer of skin just beneath the epidermis; it is composed of connective tissue and blood vessels

Edema
Swelling caused by the excessive accumulation of fluid in body tissues

Encephalitis
Inflammation of the brain that is usually caused by infection by certain bacteria or viruses

Endogenous
Arising within the body or derived from the body

Endotoxin
Poison in bacterial outer membranes that is harmful to the body, see lipopolysaccharide

Eosinophil
Amoeba-like scavenger leukocyte (white blood cell) that disposes of cellular debris; often involved in allergic responses

Epidermis
Outer, "epithelial," layer of skin

Epilepsy
A clinical condition characterized by recurrent attacks of seizures of sudden onset

Epithelial Cell
One of the closely packed cells in a thin layer that covers the internal and external surfaces of the body, including body cavities, ducts and vessels

Exogenous
Originating outside the body

Free Radical
An unstable molecule that reacts quickly with other atoms and molecules and can cause damage to living tissues

Genome
All the genetic material in the chromosomes of a particular organism

GM-CSF
Granulocyte-macrophage colony-stimulating factor; a growth factor that stimulates the growth and division of precursors of granulocytes, monocytes, and macrophages

Histamine
Molecule released especially during an allergic response that causes smooth muscle contraction, inflammation, mucus secretion, and other allergy symptoms

Hypodermis
Bottom layer of skin, below the dermis

Immune system
The body's system for protection against infection and disease; involves immune cells, antibodies, and other molecules

Infection [bacterial, viral]
Invasion of the body by harmful microorganisms such as viruses, bacteria, fungi, or parasites

Infectious disease
Disease transmitted by microorganisms

Inflammation
The immediate, defensive reaction to any injury.

Inflammatory Mediator
Molecule inside or outside the body that plays a role in inflammation

Insulin
A hormone produced in the pancreas that helps control levels of sugars, fats, and proteins in the body

Interferon
Molecule (protein) produced by virally infected cells that helps the body fight off viral infections

Interleukin
One of a class of inflammatory mediators

Leukocyte
White blood cell; acts as a part of the immune system by destroying invading cells and removing cellular debris

Leukotriene Inflammatory molecule thought to mediate the allergic response that causes lung constriction and muscle contraction in asthma

Lipopolysaccharide
Poison in bacterial outer membranes that is harmful to the body; see endotoxin

Lymphocyte
Type of leukocyte (white blood cell) that mainly resides in lymphatic tissue (e.g., the lymph nodes) and is active in immune responses, including the production of antibodies; two types include B cells and T cells

Macrophage
Type of large leukocyte (white blood cell) that uses a process called phagocytosis to eat bacteria and digest cellular debris; during inflammation, develops the ability to produce inflammatory molecules

Mast cell
Type of leukocyte (white blood cell) found in connective tissues that produces histamine and other inflammatory molecules

Meningitis
Serious inflammatory condition resulting from bacterial or viral infection of the meninges, the wrapping that surrounds the brain and spinal cord

Monocyte
Type of leukocyte (white blood cell) that engulfs and breaks down debris and invading cells; can mature into a macrophage cell

Multiple Organ Dysfunction Syndrome[MODS]
Progressive failure of several interdependent organ systems that can be a consequence of the systemic inflammation following severe injury

Multiple Sclerosis
Autoimmune disease in which the body attacks its own nervous system, destroying the myelin sheath that protects nerve cells

Myelin
A protein that covers and acts as an electrical insulator for nerve fibers

Nerve Disorders
Any of a variety of health disorders affecting the brain, spinal cord, and nervous system

Neuron
A nerve cell; it receives and conducts electrical impulses from the brain; it consists of a cell body, an axon, axon terminals, and dendrites

Neutrophil
Type of leukocyte (white blood cell) that travels through the blood to an injured site via a process called chemotaxis

Nitric Oxide
A highly reactive gas that is involved in a wide array of biological functions and functions as a part of the body's immune system

Non-Steroidal Anti-Inflammatory Drug [NSAID]
Any of a class of drugs that reduces pain, fever, or inflammation by interfering with the synthesis of prostaglandins

Pathogen
Microorganism that causes disease

Platelet
Particle (pinched off from cell called a megakaryocyte) found in the bloodstream that initiates the blood clotting process

Prostaglandin
Any of a class of hormone-like molecules that participate in diverse body functions including inflammation; their production is blocked by NSAIDs

Protein
A large molecule encoded by a gene; they are required for the structure, function, and regulation of the body's cells, tissues, and organs; examples include hormones, enzymes, and antibodies

Proteome
All the proteins made by a cell, organ, or organism at a particular time and under specific conditions

Resuscitation
Process of reviving a patient from unconsciousness and restoring vital functions such as breathing

Shock
"Circulatory collapse," when blood pressure drops too low to maintain an adequate supply of blood to the body's tissues

Sepsis
Amplified, body-wide inflammatory response to traumatic injury, severe bleeding, or an infection caused by microorganisms like bacteria or fungi; typical symptoms include fever, mental confusion, a drop in blood pressure, and lung and kidney failure

Systemic Inflammation
Inflammation throughout the body

Systemic Inflammatory Response Syndrome [SIRS]
The syndrome of systemic inflammatory response to a major injury

T Cell
A type of cell produced by the thymus that plays a major role in immune reactions

Toll-Like Receptor [TLR]
Molecule on cell surfaces that helps the body sense the presence of endotoxin and other microbial products, and sends an alert to the immune system

Tumor Necrosis Factor [TNF]
Cytokine produced primarily by monocytes and macrophages

Trauma (Physical Trauma)
Wound or injury caused by a physical force; examples include the consequences of motor vehicle accidents, falls, drowning, gunshots, fires and burns, and stabbings

VCAM-1
Vascular Cell Adhesion Molecule-1; One of a number of molecules on the surface of endothelial cells that controls cell adhesion and movement

Virus
Infectious agent composed of a protein coat around a DNA or RNA core; to reproduce, viruses depend on living cells

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	Contents © 2004-2007 Massachusetts General Hospital			a b c d e f g h ijkl m nopqr s tuvwxyz Acute Respiratory Distress Syndrome [ARDS] Life-threatening condition that develops when inflammation and injury to the lungs causes fluid buildup in the airways Adhesion Molecule Any of a large number of cell-surface molecules of several different classes that affect the attachment of one cell to another Antibody A protein produced by the immune system in response to an antigen, often a virus or bacterium Arthritis The inflammation of a joint Asthma Chronic condition causing difficulty breathing caused by over-reactive airways Atherosclerosis One of many diseases in which fat builds up in the large- and medium-sized arteries, restricting blood flow Autoimmune Disease Disorder in which the immune system mistakenly attacks and destroys body tissue that it believes to be foreign B Cell A cell produced by the bone marrow that becomes either a memory cell or a plasma cell that forms antibodies against a foreign substance Bacterium Tiny, one-celled organism that reproduces by cell division and can be found in virtually any environment Basophil Type of white blood cell that contains inflammatory mediators such as histamine Cancer Disease caused by the abnormal and uncontrolled division of cells that invade and destroy surrounding body tissues Chemokine Molecule that causes white blood cells such as neutrophils and monocytes to move throughout the body (e.g., toward an injury) via the process of chemotaxis Chemotaxis Movement of a cell toward or away from a chemical substance Cholesterol A fatty substance that higher organisms use in the construction of cell membranes and as an ingredient for making steroid molecules; it is carried through the bloodstream in molecules called lipoproteins Compensatory Anti-Inflammatory Response Syndrome [CARS] Condition that develops in some resuscitated injured patients when the body compensates in an effort to stop inflammation Complement System Set of molecules in the blood activated by the presence of bacteria, injury or other immune triggers, causing a range of responses associated with starting and maintaining inflammation COX Abbreviation for the enzyme cyclooxygenase; the molecular target of nonsteroidal anti-inflammatory drugs (NSAIDs) COX Inhibitor Drug that blocks the action of the COX enzyme C-Reactive Protein [CRP] Protein not normally found at high levels in the blood of healthy people, but when present it indicates inflammation Cytokine Molecule that controls reactions among cells; key component of inflammation Dermis Layer of skin just beneath the epidermis; it is composed of connective tissue and blood vessels Edema Swelling caused by the excessive accumulation of fluid in body tissues Encephalitis Inflammation of the brain that is usually caused by infection by certain bacteria or viruses Endogenous Arising within the body or derived from the body Endotoxin Poison in bacterial outer membranes that is harmful to the body, see lipopolysaccharide Eosinophil Amoeba-like scavenger leukocyte (white blood cell) that disposes of cellular debris; often involved in allergic responses Epidermis Outer, "epithelial," layer of skin Epilepsy A clinical condition characterized by recurrent attacks of seizures of sudden onset Epithelial Cell One of the closely packed cells in a thin layer that covers the internal and external surfaces of the body, including body cavities, ducts and vessels Exogenous Originating outside the body Free Radical An unstable molecule that reacts quickly with other atoms and molecules and can cause damage to living tissues Genome All the genetic material in the chromosomes of a particular organism GM-CSF Granulocyte-macrophage colony-stimulating factor; a growth factor that stimulates the growth and division of precursors of granulocytes, monocytes, and macrophages Histamine Molecule released especially during an allergic response that causes smooth muscle contraction, inflammation, mucus secretion, and other allergy symptoms Hypodermis Bottom layer of skin, below the dermis Immune system The body's system for protection against infection and disease; involves immune cells, antibodies, and other molecules Infection [bacterial, viral] Invasion of the body by harmful microorganisms such as viruses, bacteria, fungi, or parasites Infectious disease Disease transmitted by microorganisms Inflammation The immediate, defensive reaction to any injury. Inflammatory Mediator Molecule inside or outside the body that plays a role in inflammation Insulin A hormone produced in the pancreas that helps control levels of sugars, fats, and proteins in the body Interferon Molecule (protein) produced by virally infected cells that helps the body fight off viral infections Interleukin One of a class of inflammatory mediators Leukocyte White blood cell; acts as a part of the immune system by destroying invading cells and removing cellular debris Leukotriene Inflammatory molecule thought to mediate the allergic response that causes lung constriction and muscle contraction in asthma Lipopolysaccharide Poison in bacterial outer membranes that is harmful to the body; see endotoxin Lymphocyte Type of leukocyte (white blood cell) that mainly resides in lymphatic tissue (e.g., the lymph nodes) and is active in immune responses, including the production of antibodies; two types include B cells and T cells Macrophage Type of large leukocyte (white blood cell) that uses a process called phagocytosis to eat bacteria and digest cellular debris; during inflammation, develops the ability to produce inflammatory molecules Mast cell Type of leukocyte (white blood cell) found in connective tissues that produces histamine and other inflammatory molecules Meningitis Serious inflammatory condition resulting from bacterial or viral infection of the meninges, the wrapping that surrounds the brain and spinal cord Monocyte Type of leukocyte (white blood cell) that engulfs and breaks down debris and invading cells; can mature into a macrophage cell Multiple Organ Dysfunction Syndrome[MODS] Progressive failure of several interdependent organ systems that can be a consequence of the systemic inflammation following severe injury Multiple Sclerosis Autoimmune disease in which the body attacks its own nervous system, destroying the myelin sheath that protects nerve cells Myelin A protein that covers and acts as an electrical insulator for nerve fibers Nerve Disorders Any of a variety of health disorders affecting the brain, spinal cord, and nervous system Neuron A nerve cell; it receives and conducts electrical impulses from the brain; it consists of a cell body, an axon, axon terminals, and dendrites Neutrophil Type of leukocyte (white blood cell) that travels through the blood to an injured site via a process called chemotaxis Nitric Oxide A highly reactive gas that is involved in a wide array of biological functions and functions as a part of the body's immune system Non-Steroidal Anti-Inflammatory Drug [NSAID] Any of a class of drugs that reduces pain, fever, or inflammation by interfering with the synthesis of prostaglandins Pathogen Microorganism that causes disease Platelet Particle (pinched off from cell called a megakaryocyte) found in the bloodstream that initiates the blood clotting process Prostaglandin Any of a class of hormone-like molecules that participate in diverse body functions including inflammation; their production is blocked by NSAIDs Protein A large molecule encoded by a gene; they are required for the structure, function, and regulation of the body's cells, tissues, and organs; examples include hormones, enzymes, and antibodies Proteome All the proteins made by a cell, organ, or organism at a particular time and under specific conditions Resuscitation Process of reviving a patient from unconsciousness and restoring vital functions such as breathing Shock "Circulatory collapse," when blood pressure drops too low to maintain an adequate supply of blood to the body's tissues Sepsis Amplified, body-wide inflammatory response to traumatic injury, severe bleeding, or an infection caused by microorganisms like bacteria or fungi; typical symptoms include fever, mental confusion, a drop in blood pressure, and lung and kidney failure Systemic Inflammation Inflammation throughout the body Systemic Inflammatory Response Syndrome [SIRS] The syndrome of systemic inflammatory response to a major injury T Cell A type of cell produced by the thymus that plays a major role in immune reactions Toll-Like Receptor [TLR] Molecule on cell surfaces that helps the body sense the presence of endotoxin and other microbial products, and sends an alert to the immune system Tumor Necrosis Factor [TNF] Cytokine produced primarily by monocytes and macrophages Trauma (Physical Trauma) Wound or injury caused by a physical force; examples include the consequences of motor vehicle accidents, falls, drowning, gunshots, fires and burns, and stabbings VCAM-1 Vascular Cell Adhesion Molecule-1; One of a number of molecules on the surface of endothelial cells that controls cell adhesion and movement Virus Infectious agent composed of a protein coat around a DNA or RNA core; to reproduce, viruses depend on living cells [return to top]