| agammaglobulinemia |
Also called hypogammaglobulinemia. The absence of or severely reduced levels of
antibodies in serum. |
| allergen |
A substance
that provokes an allergic response |
| anaphylaxis |
The unusual or exaggerated allergic reaction to antigen that leads to severe
respiratory and cardiac complications. |
| Arthus reaction |
An immune
complex phenomenon that develops after repeat injection. This localized inflammation
results from aggregates of antigen and antibody that bind, complement, and attract
neutrophils. |
| atopy |
Allergic reaction classified as type I, with a strong familial relationship;
caused by allergens such as pollen, insect venom, food, and dander; involves IgE antibody;
includes symptoms of hay fever, asthma, and skin rash |
| autoimmunity |
The
pathologic condition arising from the production of antibodies against autoantigens.
Example: rheumatoid arthritis. |
| bradykinin |
An active polypeptide that is a potent vasodilator released from IgE-coated mast
cells during anaphylaxis. |
| eczema |
An acute or
chronic allergy of the skin associated with itching and burning sensations. Typically,
red, edematous, vesicular lesions erupt, leaving the skin scaly and sometimes
hyperpigmented |
| histamine |
A cytokine released when mast cells and basophils release their granules. An
important mediator of allergy, its effects include smooth muscle contraction, increased
vascular permeability, and increased mucus secretion. |
| Hypogamma-globulinemia |
An inborn
disease in which the gamma globulin (antibody) fraction of serum is greatly reduced. The
condition is associated with a high susceptibility to pyogenic infections |
| isograft |
Transplanted tissue from one monozygotic twin to the other; transplants between
highly inbred animals that are genetically identical |
| neoplasm |
A synonym
for tumor |
| prostaglandin |
A hormonelike substance that regulates many body functions. Prostaglandin comes
from a family of organic acids containing 5-carbon rings that are essential to the human
diet. |
| sensitizing dose |
The initial
effective exposure to an antigen or an allergen that stimulates an immune response. Often
applies to allergies. |
| serotonin |
A vascoconstrictor that inhibits gastric secretion and stimulates smooth muscle. |
| universal donor |
In blood
grouping and transfusion, a group O individual whose erythrocytes bear neither
agglutinogen A nor B. |
| wheal |
A welt; a marked, slightly red, usually itchy area of the skin that changes in
size and shape as it extends to adjacent area. The reaction is triggered by cutaneous
contact or intradermal injection of allergens in sensitive individuals. |
