Appendixes
Appendix A
Glossary
A
Antibody:
An immunoglobulin molecule that has a specific amino acid sequence such that it interacts only with the antigen that induced its synthesis in lymphoid tissue, or with an antigen closely related to it.
Antigen:
Any substance that is capable, under appropriate conditions, of inducing the formation of antibodies and of reacting specifically in some detectable manner with the antibodies so induced.
Papooses:
A mechanism by which cells self-distract when stimulated by the appropriate trigger.
Atherosclerosis:
A common form of arteriosclerosis in which deposits of yellowish plaque containing cholesterol, lipoid material, and lipophages are formed within the large and medium-sized arteries.
B
B cell, B lymphocyte:
Bone marrow derived lymphocyte; originally differentiating in bone marrow, it can mature and multiply in the lymphoid organs when suitably stimulated.
Base pair:
Polynucleotide pairs with each Purina base linked to its complementary pyridine base in the opposite DNA chain.
Binding proteins:
Proteins with a high affinity for binding a drug so that its overall potency is reduced and its effect prolonged as a result of its level being maintained in the blood plasma.
C
Chimeric viruses:
Viruses into which genes from a different virus have been introduced.
Chorioallantoic membrane:
A membrane in birds, adjacent to the egg shell, that surrounds the embryo and contributes to gas exchange.
cram gene:
A cytosine response modifier gene that inhibits the proteolytic activation of interleukin-1 beta, thereby suppressing its response to infection.
Cytosine:
Any of a class of phytohormones whose principal functions are the induction of cell division and the regulation of differentiation of tissue.
Cytotoxic:
Pertaining to, resulting from, or having the action of a cytotoxin.
Cytotoxin:
A toxin or antibody that has a specific toxic action on cells of special organs; cytotoxins are named according to the cells for which they are specific.
D
DNA:
Deoxyribonucleic acid, a double-helix polymer encoding genetic information for the transmission of inherited traits; comprises two long, linked chains of monomer nucleotides consisting of a deoxyribose sugar molecule to which is attached a phosphate group and one of four nitrogenous bases—two purines (adenine and guanine) and two pyrimidines (cytosine and thymine).
DNA amplification primer:
A short stretch of nucleotides that bind, or anneal, to the DNA sequence to be cloned and serve as the starting point for copying in a polymerase chain reaction.
DNA clone:
A DNA fragment produced by propagating and storing a large number of identical molecules having a selected DNA fragment as their single ancestor.
E
Enanthem:
An eruption upon a mucous surface.
Encephalitis:
Acute disease of the central nervous system seen in persons convalescing from infectious disease, usually one of viral origin.
Epithelial cell:
Surface layer of cells closely bound to one another to form continuous sheets covering surfaces that may come into contact with foreign substances.
Exanthema:
A condition frequently seen in children, marked by intermittent fever lasting 3 days, falling by crisis, and followed a few hours later by a rash on the trunk.
G
Genetic recombination:
The formation of new combinations of genes as a result of crossing over between homologous chromosomes.
Genome:
A set of chromosomes containing the heritable genetic material that directs gene development.
H
Hemagglutinin:
An antibody that agglutinates erythrocytes.
Hypotension:
Abnormally low blood pressure.
I
IgM antibody:
A large immunoglobulin protein with extremely high molecular weight of 19 S.
IgG antibody:
A large immunoglobulin protein with a molecular weight of 7 S.
Immunity, active:
Acquired immunity attributable to the presence of antibody or immune lymphoid cells and phagocytic cells formed in response to antigenic stimulus.
Immunity, herd:
The resistance of a group to attack by a disease because the existing immunity of a large proportion of the members lessens the likelihood that an affected individual will come into contact with a susceptible individual.
Immunity, passive:
Acquired immunity produced by the administration of preformed antibody or specifically sensitized lymphoid cells.
Immunogen:
An antigen that can induce antibody production.
Immunogenicity:
The potency of an immunogen to produce immunity.
Immunoglobulin:
A protein found in serum and other body fluids and tissues; it functions as a specific antibody that activates humoral aspects of immunity; five classes, based on different antigenic activity, are IgA, IgD, IgE, IgG, and IgM.
Interferon:
A soluble, small, cell-specific protein that inhibits virus multiplication.
Intravascular coagulopathy:
A disorder characterized by excessive blood clotting within blood vessels.
L
Leukocyte:
A cellular component of blood that helps defend the body from infection by ingesting foreign materials and providing antibodies.
Lymphocyte:
A type of leukocyte (white blood cell) that is of fundamental importance in the immune system, making up 20 to 25 percent of the total number of leukocytes.
Lymphokine:
A soluble protein mediator, released by sensitized lymphocytes on contact with antigens, that plays a role in macrophage activation, lymphocyte transformation, and cell-mediated immunity.
Lysis:
Destruction of cells by a specific antibody.
M
Macrophage:
Large phagocytic cells occurring in the walls of blood vessels; usually immobile, they become mobile when stimulated by inflammation.
Malpighlian layer:
The layer of epithelial cells in the epidermis next to the grain surface of the derma where protoplasm has not yet changed into horny material.
MHC molecules:
Major histocompatibility complex molecules that are found on the surface of almost all nucleated somatic cells; they control cellular immune reactions and are largely responsible for the rejection of organ transplants.
Monocyte:
A mononuclear phagocytic leukocyte.
Morphogenesis:
The development of the structural features of an organism or part.
Mucous membrane:
Membrane lining body cavities and canals that lead to the outside; chiefly the respiratory, digestive, and urogenital tracts.
N
Necrosis:
Death of tissue, usually as individual cells or groups of cells, or in small localized areas.
O
Open reading frame:
Two separate additions or deletions of one or two base pairs (reading frame shift) in a DNA sequence such that the second shift restores the reading frame, effectively ''skipping" the amino acids coded between the two.
P
Papule:
A small, circumscribed, superficial, solid elevation of the skin.
Paracrine ligand mimics:
Molecules that behave like growth factors or cytokines.
Pathogen:
Any disease-producing microorganism or material.
Phagocyte:
Cells that ingest microorganisms or other cells and foreign particles.
Plasma:
The fluid portion of the blood in which particulate components are suspended.
Plasmid:
A generic term for all types of intracellular inclusions that can be considered as having genetic functions.
Polymerase chain reaction:
A technique used to make numerous copies of a specific segment of DNA quickly and accurately; a three-step process carried out in repeated cycles that includes denaturation, or separation, of the two strands of the DNA molecule, each of which is a template on which a new strand is built in the second step, and to which the DNA polymerase adds nucleotides onto the annealed primers in the third step to double the DNA in each cycle.
Prodrome:
Premonitory symptom.
Protein:
Any one of a group of complex organic nitrogenous compounds that are the principal constituents of cell protoplasm.
Pustule:
A visible collection of puss within or beneath the epidermis.
R
Raft culture:
Three-dimensional tissue culture, as opposed to a single-layer culture.
Reactogenicity:
A nonspecific reaction at the site of inoculation, ranging from redness to induration to a lesion or pustule.
Reading frame:
The set of nucleotide pairs coding for one particular amino acid in the sequence of several thousand nucleotides in a gene; addition or deletion of one or two nucleotide pairs shifts the reading frame from that point to the end of the molecule.
Reticulum cell hyperplasia:
Overproliferation of stromal cells from certain organs, such as the spleen.
RNA:
Ribonucleic acid, a complex compound of high molecular weight that functions in cellular protein synthesis and replaces DNA (deoxyribonucleic acid) as a carrier of genetic codes in some viruses.
S
Serine proteinase inhibitor:
Protein that blocks the action of host proteases that regulate immunity or inflammation.
Seroconversion:
Development of antibodies in response to inoculation with a vaccine.
Serpins:
Serine (crystalline amino acid) protease inhibitor.
Signal transduction:
Transmission of a signal from one cell to another.
Subunit protein vaccines:
Vaccines incorporating relevant proteins from a virus instead of the entire virus genome.
SCID mouse:
Severe combined imunodeficiency mouse, a mouse with a genetic inability to create diversity in its lymphocytes (no functional recombinase gene), so that it lacks an effective immune response; reconstitution with human cells (SCID-hu) can enable the mice to be used to study human diseases.
T
T cell, T lymphocyte:
Thymus-derived lymphocyte, referring to lymphatic cell dependency on the maturation process that occurs in the thymus.
Thymic dysplasia:
Any of a group of hereditary disorders characterized by faulty development of the thymus, which may be associated with normal serum immunoglobulin levels and impaired cell-mediated immunity (Nezelof's syndrome), agammaglobulinemia and impairment of both cell-mediated and humoral immunity, or variable deficiencies of immunoglobulins.
Titer:
The quantity of a substance required to produce a reaction with a given volume of another substance.
TNF:
Tumor necrosis factor, a protein produced by macrophages when they encounter the poisonous substance in bacteria known as endotoxin.
Transgenic:
The property of having genes from other species inserted into the genome.
Tropism:
The orientation of an organism to an external stimulus.
U
Umbilication:
A central, navel-like depression.
V
Vascular restenosis:
Narrowing of blood vessels.
Vesicle:
A small bladder or sack containing liquid; a small blister with circumscribed elevation of the epidermis containing a serous liquid.
Virion:
The complete viral particle, found extracellularly and capable of surviving in crystalline form and infecting a living cell.
Viremia:
The presence of viruses in the blood, usually characterized by malaise, fever, and aching of the back and extremities.