There are a few terms used in this website that are not in common use. This glossary is to give a quick definition of some terms. The definitions are taken from the Merriam-Webster Medical Dictionary; if you need additional definitions, the entire dictionary is available online from Medline at http://www.nlm.nih.gov/medlineplus/mplusdictionary.html. For drug information see Immunosuppressant Drugs, or the Drug Information section of the TransplantBuddies Library.

A
allograft	a homograft between allogeneic individuals
anastomosis	1 a: a communication between or coalescence of blood vessels; b: the surgical union of parts and esp. hollow tubular parts <~ of the ureter and colon is surgically practicable>
angiogram	a roentgenogram made by angiography
angioplasty	surgical repair of a blood vessel : specifically balloon angioplasty, a procedure in which a catheter is guided to the site of a narrowed artery, the tip of the catheter is then expanded, widening the lumen of the artery.
antibody	any of a large number of proteins of high molecular weight that are produced normally by specialized B cells after stimulation by an antigen and act specifically against the antigen in an immune response, that are produced abnormally by some cancer cells, and that typically consist of four subunits including two heavy chains and two light chains -called also immunoglobulin
antigen	a usu. protein or carbohydrate substance (as a toxin or enzyme) capable of stimulating an immune response
antilymphocyte globulin:	serum globulin containing antibodies against lymphocytes that is used similarly to antilymphocyte serum
arteriogram	a roentgenogram of an artery made by arteriography
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B
B lymphocyte	B CELL
basophil	a basophilic substance or structure; a white blood cell with basophilic granules that is similar in function to a mast cell
biopsy	A biopsy refers to a procedure that involves obtaining a tissue specimen for microscopic analysis to establish a precise diagnosis. Biopsies can be accomplished with a biopsy needle (passed through the skin into the organ in question) or by open surgical incision.
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C
cascade	a molecular, biochemical, or physiological process occurring in a succession of stages each of which is closely related to or depends on the output of the previous stage <a ~ of enzymatic reactions> <the ~ of events comprising the immune response>
catecholamine	any of various substances (as epinephrine, norepinephrine, and dopamine) that contain a benzene ring with two adjacent hydroxyl groups and a side chain of ethylamine and that function as hormones or neurotransmitters or both
cecum	a cavity open at one end (as the blind end of a duct); the blind pouch at the beginning of the large intestine into which the ileum opens from one side and which is continuous with the colon
corticosteroid	any of various adrenal-cortex steroids (as corticosterone, cortisone, and aldosterone) used esp. as anti-inflammatory agents compare
cytokine	any of a class of immunoregulatory substances (as lymphokines) that are secreted by cells of the immune system
cytotoxic T lymphocyte	KILLER T CELL
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D
diabetes mellitus	a variable disorder of carbohydrate metabolism caused by a combination of hereditary and environmental factors and usu. Characterized by inadequate secretion or utilization of insulin, by excessive urine production, by excessive amounts of sugar in the blood and urine, and by thirst, hunger, and loss of weight see INSULIN-DEPENDENT DIABETES MELLITUS, NON-INSULIN-DEPENDENT DIABETES MELLITUS
dialysis	the separation of substances in solution by means of their unequal diffusion through semipermeable membranes
distal	situated away from the point of attachment or origin or a central point; as located away from the center of the body <the ~ end of a bone> compare PROXIMAL
duodenum	the first, shortest, and widest part of the small intestine that in humans is about 10 inches (25 centimeters) long and that extends from the pylorus to the undersurface of the liver where it descends for a variable distance and receives the bile and pancreatic ducts and then bends to the left and finally upward to join the jejunum near the second lumbar vertebra
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E
eosinophil	a white blood cell or other granulocyte with cytoplasmic inclusions readily stained by eosin
ESRD	end-stage renal disease
exocrine	producing, being, or relating to a secretion that is released outside its source <~ pancreatic cells> <~ functions> <~ insufficiency>
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F
fascia	The flat layers of fibrous tissue that separate different layers of tissue.
Foley catheter	a catheter with an inflatable balloon tip for retention in the bladder
fossa	A pit, groove, cavity, or depression, of greater or less depth; as, the temporal fossa on the side of the skull
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G
genotype	all or part of the genetic constitution of an individual or group compare PHENOTYPE
glomerulus	a small convoluted or intertwined mass (as of organisms, nerve fibers, or capillaries): as a: a tuft of capillaries that is covered by epithelium, is situated at the point of origin of each vertebrate nephron, and normally passes a protein-free filtrate from the blood to the surrounding Bowman's capsule
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H
haplotype	a set of genes that determine different antigens but are closely enough linked to be inherited as a unit; the antigenic phenotype determined by a haplotype
hemodialysis	the process of removing blood from an artery (as of a kidney patient), purifying it by dialysis, and returning it to a vein
hepatic artery	the branch of the celiac artery that supplies the liver with arterial blood
histocompatibility	a state of mutual tolerance between tissues that allows them to be grafted effectively see MAJOR HISTOCOMPATIBILITY COMPLEX
histocompatibility antigen	any of the antigenic glycoproteins on the surface membranes of cells that enable the body's immune system to recognize a cell as native or foreign and that are determined by the major histocompatibility complex
HLA:	1: the major histocompatibility complex in humans 2: a genetic locus, gene, or antigen of the major histocompatibility complex in humans -often used attributively <HLA antigens> <HLA typing> -often used with one or more letters to designate a locus or with letters and a number to designate an allele at the locus or the antigen corresponding to the locus and allele <relationship ... between HLA-B27 antigen and ankylosing spondylitis G. E. Ehrlich>
HLA typing	See TISSUE TYPING
human leukocyte antigen:	HLA 2
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I
ileum	the last division of the small intestine that constitutes the part between the jejunum and large intestine and in humans forms the last three fifths of the part of the small intestine beyond the end of the duodenum and that is smaller and thinner-walled than the jejunum with fewer circular folds but more numerous Peyer's patches
iliac artery	1: either of the large arteries supplying blood to the lower trunk and hind limbs and arising by bifurcation of the aorta which in humans occurs at the level of the fourth lumbar vertebra to form one vessel for each side of the body -called also common iliac artery 2: the outer branch of the common iliac artery on either side of the body that passes beneath the inguinal ligament to become the femoral artery -called also external iliac artery 3: the inner branch of the common iliac artery on either side of the body that soon breaks into several branches and supplies blood chiefly to the pelvic and gluteal areas -called also hypogastric artery, internal iliac artery
iliac fossa	the inner concavity of the ilium
iliac fascia	an aponeurotic layer lining the back part of the abdominal cavity and covering the inner surface of the psoas and iliacus muscles
iliac vein	1: any of several veins on each side of the body corresponding to and accompanying the iliac arteries a: either of two veins of which one is formed on each side of the body by the union of the external and internal iliac veins and which unite to form the inferior vena cava -called also common iliac vein 2: a vein that drains the leg and lower part of the anterior abdominal wall, is an upward continuation of the femoral vein, and unites with the internal iliac vein called also external iliac vein 3: a vein that drains the pelvis and gluteal and perineal regions, accompanies the internal iliac artery, and unites with the external iliac vein to form the common iliac vein -called also hypogastric vein, internal iliac vein
insulin-dependent diabetes mellitus	a form of diabetes mellitus that usu. develops during childhood or adolescence and is characterized by a severe deficiency in insulin secretion resulting from atrophy of the islets of Langerhans and causing hyperglycemia and a marked tendency toward ketoacidosis -abbr. IDDM -called also insulin-dependent diabetes, juvenile diabetes, juvenile-onset diabetes, type I diabetes
interleukin	any of various compounds of low molecular weight that are produced by lymphocytes, macrophages, and monocytes and that function esp. in regulation of the immune system and esp. cell-mediated immunity
interleukin-1	an interleukin produced esp. by monocytes and macrophages that regulates cell-mediated and humoral immune responses by activating lymphocytes and mediates other biological processes (as the onset of fever) usu. associated with infection and inflammation -abbr. IL-1
interleukin-2	an interleukin produced by antigen-stimulated helper T-cells in the presence of interleukin-1 that induces proliferation of immune cells (as T cells and B cells) and has been used experimentally esp. in treating certain cancers -abbr. IL-2
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J
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L
lymph	a usu. clear coagulable fluid that passes from intercellular spaces of body tissue into the lymphatic vessels, is discharged into the blood by way of the thoracic duct and right lymphatic duct, and resembles blood plasma in containing white blood cells and esp. lymphocytes but normally few red blood cells and no platelets
lymphatic	vessel that contains or conveys lymph, that originates as an interfibrillar or intercellular cleft or space in a tissue or organ, and that if small has no distinct walls or walls composed only of endothelial cells and if large resembles a vein in structure -called also lymphatic vessel, lymph vessel
lymphocyte	any of the colorless weakly motile cells that originate from stem cells and differentiate in lymphoid tissue (as of the thymus or bone marrow), that are the typical cellular elements of lymph, that include the cellular mediators of immunity, and that constitute 20 to 30 percent of the white blood cells of normal human blood see B CELL T CELL
lymphoid cell	any of the cells responsible for the production of immunity mediated by cells or antibodies and including lymphocytes, lymphoblasts, and plasma cells
lymphokine	any of various substances (as an interleukin) of low molecular weight that are not antibodies, are secreted by T cells in response to stimulation by antigens, and have a role (as the activation of macrophages or the enhancement or inhibition of antibody production) in cell-mediated immunity
lymphokine-activated killer cell	A lymphocyte that has been turned into a cancer-killing cell by being cultured with interleukin-2
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M
macrophage	a phagocytic tissue cell of the mononuclear phagocyte system that may be fixed or freely motile, is derived from a monocyte, and functions in the protection of the body against infection and noxious substances
major histocompatibility complex	a group of genes that function esp. in determining the histocompatibility antigens found on cell surfaces and that in humans comprise the alleles occurring at four loci on the short arm of chromosome 6 -abbr. MHC
mast cell	a large cell that occurs esp. in connective tissue and has basophilic granules containing substances (as histamine and heparin) which mediate allergic reactions
MHC	major histocompatibility complex
monocyte	a large white blood cell with finely granulated chromatin dispersed throughout the nucleus that is formed in the bone marrow, enters the blood, and migrates into the connective tissue where it differentiates into a macrophage
MRI	magnetic resonance imaging : a noninvasive diagnostic technique that produces computerized images of internal body tissues and is based on nuclear magnetic resonance of atoms within the body induced by the application of radio waves
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N
neutrophil	a granulocyte that is the chief phagocytic white blood cell
non-insulin-dependent diabetes mellitus	common form of diabetes mellitus that develops esp. in adults and most often in obese individuals and that is characterized by hyperglycemia resulting from impaired insulin utilization coupled with the body's inability to compensate with increased insulin production -abbr. NIDDM -called also adult-onset diabetes, late-onset diabetes, maturity-onset diabetes, non-insulin-dependent diabetes, type II diabetes
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O
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P
pancreas	a large lobulated gland that in humans lies in front of the upper lumbar vertebrae and behind the stomach and is somewhat hammer-shaped and firmly attached anteriorly to the curve of the duodenum with which it communicates through one or more pancreatic ducts and that consists of (1) tubular acini secreting digestive enzymes, which pass to the intestine and function in the breakdown of proteins, fats, and carbohydrates; (2) modified acinar cells that form islets of Langerhans between the tubules and secrete the hormones insulin and glucagon; and (3) a firm connective-tissue capsule that extends supportive strands into the organ
peritoneal dialysis	In this type of dialysis, a special solution is run through a tube into the peritoneum, a thin tissue that lines the cavity of the abdomen. The body's waste products are removed through the tube. There are three types of peritoneal dialysis. Continuous ambulatory peritoneal dialysis (CAPD), the most common type, needs no machine and can be done at home. Continuous cyclic peritoneal dialysis (CCPD) uses a machine and is usually performed at night when the person is sleeping. Intermittent peritoneal dialysis (IPD) uses the same type of machine as CCPD, but is usually done in the hospital because treatment takes longer.
peritoneum	the smooth transparent serous membrane that lines the cavity of the abdomen of a mammal, is folded inward over the abdominal and pelvic viscera, and consists of an outer layer closely adherent to the walls of the abdomen and an inner layer that folds to invest the viscera
phagocyte	a cell (as a white blood cell) that engulfs and consumes foreign material (as microorganisms) and debris
phenotype	the visible properties of an organism that are produced by the interaction of the genotype and the environment compare GENOTYPE
portal vein	a large vein that is formed by fusion of other veins, that terminates in a capillary network, and that delivers blood to some area of the body other than the heart : HEPATIC PORTAL VEIN
proximal	situated next to or near the point of attachment or origin or a central point <the ~ was ... better than the peripheral stump for a graft Annual Rev. of Med.>; located toward the center of the body <the ~ end of a bone> compare DISTAL
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Q
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R
rectus abdominus	a long flat muscle on either side of the linea alba extending along the whole length of the front of the abdomen, arising from the pubic crest and symphysis, inserted into the cartilages of the fifth, sixth, and seventh ribs, and acting to flex the spinal column, tense the anterior wall of the abdomen, and assist in compressing the contents of the abdomen
renal artery	either of two branches of the abdominal aorta of which each supplies one of the kidneys, arises immediately below the origin of the corresponding superior mesenteric artery, divides into four or five branches which enter the hilum of the kidney, and gives off smaller branches to the ureter, adrenal gland, and adjoining structures
renal vein	a short thick vein that is formed in each kidney by the convergence of the interlobar veins, leaves the kidney through the hilum, and empties into the inferior vena cava
Rh factor	any of one or more genetically determined antigens usu. present in the red blood cells of humans and higher animals and capable of inducing intense immunogenic reactions -called also rhesus factor
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S
self	material that is part of an individual organism <ability of the immune system to distinguish ~ from nonself>
Sertoli cell	any of the elongated striated cells in the seminiferous tubules of the testis to which the spermatids become attached and from which they apparently derive nourishment. Named for discoverer Enrico Sertoli, 19th century Italian histologist.
stenosis	a narrowing or constriction of the diameter of a bodily passage or orifice <esophageal ~>
stent	A tube made of metal or plastic that is inserted into a vessel or passage to keep the lumen open and prevent closure due to a stricture or external compression. Stents are commonly used to keep blood vessels open in the coronary arteries, into the esophagus for strictures or cancer, the ureters to maintain drainage from the kidneys, or the bile duct for pancreatic cancer or cholangiocarcinoma.
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T
T-helper lymphocyte	HELPER T CELL
thymocyte	a cell of the thymus; a thymic lymphocyte
tissue typing	the determination of the degree of compatibility of tissues or organs from different individuals based on the similarity of histocompatibility antigens esp. on lymphocytes and used esp. as a measure of potential rejection in an organ transplant procedure HLA TYPING
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U
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V
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W
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X
xenograft	a graft of tissue taken from a donor of one species and grafted into a recipient of another species -called also heterograft, heterotransplant, xenotransplant
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Y
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Z
zygote	a cell formed by the union of two gametes; the developing individual produced from such a cell