Untitled - D Ank Unlimited

primary follicle 592 primary structure
patients manifest high titers of antimitochondrial antibodies.
IgM in the serum is elevated. Lymphocytic infiltration and
intrahepatic bile duct destruction occur. Alkaline phosphatase
is greatly increased, in addition to the elevation of
IgM and antimitochondrial antibodies. The M2 antimitochondrial
antibody is most frequently associated with PBC.
In addition to hepatosplenomegaly and skin hyperpigmentation,
patients may develop severe jaundice, petechiae, and
purpura as the disease progresses. Liver transplantation is the
only treatment for end-stage disease.
primary follicle
A densely packed accumulation of resting mature B
lymphocytes and macrophages in a network of follicular
dendritic cells from secondary lymphoid tissues such as the
lymph node cortex or the splenic white pulp, where resting
unstimulated B cells develop into germinal centers when
stimulated by antigen.
primary granule
Azurophil granule.
Antibody Titer
= Anti-A
= Anti-B
Antigen A
Primary
Anti-A response
Antigen A
+
Antigen B
0 2 4 6
Time in Weeks
Primary immune response.
Secondary
Anti-A response
Primary
Anti-B response
8 10 12
primary immune response
The body’s adaptive immune response to first contact with
antigen. It is characterized by a lag period of a few days
following antigen administration before antibodies or specific
T lymphocytes are detectable. The antibody produced
consists mostly of IgM and is of relatively low titer and
low affinity. This is in contrast to the secondary immune
response, in which the latent period is relatively brief and
IgG is the predominant antibody. The most important component
of the primary response is the activation of memory
cells that recognize antigen immediately on second encounter
with antigen, leading to a secondary response. A similar
pattern is followed in cell-mediated responses.
primary immunodeficiency
Diminished immune reactivity attributable to an intrinsic
abnormality of T or B lymphocytes. Development failure
of a segment of the immune system as a consequence of an
inborn genetic mutation.
primary interaction
Antigen and antibody binding that may or may not lead to
a secondary visible reaction such as precipitation. Primary
antigen–antibody interaction may be measured by equilibrium
dialysis, the Farr assay, fluorescence polarization,
fluorescence quenching, and selected radioimmunoassays
such as radioimmunoelectrophoresis.
primary lymphoid follicles
B cell regions, comprised of resting B lymphocytes, of secondary
lymphoid tissues unstimulated by an immune response.
primary lymphoid organ
The site of maturation of B or T lymphocytes. The primary
lymphoid organ for B lymphocytes is the bursa of Fabricius
in avian species and the bone marrow in adult mammals.
By contrast, T cell development occurs in the thymus of
all vertebrates. Stem cell maturation in primary lymphoid
organs occurs without stimulation by antigen.
primary lymphoid tissues
Bone marrow and thymus, the sites of lymphoid development.
primary lysosome
A lysosome that has not yet fused with a phagosome.
primary nodule
Refer to primary follicle.
primary reaction
The actual binding of antibody, via its Fab or antigenbinding
fragment, to its homologous antigen to form an
antibody–antigen complex. After initial contact, the union
of the two substances takes place almost instantaneously
(within milliseconds).
primary response
First response to an immunogen to which the recipient has
not been previously exposed. Both B and T lymphocytes
are activated by epitopes to proliferate and differentiate into
antigen-effector lymphocytes and memory cells. It is principally
an IgM response and generates immunologic memory.
primary sclerosing cholangitis (PSC)
A possible autoimmune liver disease characterized by
inflammation of the large intra- and extrahepatic bile ducts
that eventually leads to strictures and dilatations. The bile
ducts eventually become stenotic and small intrahepatic
bile ducts disappear. Although its etiology is unknown,
chronic portal bacteremia, toxic bile acids, chronic viral
infections, ischemic vascular injury, and immunoregulatory
disorders have been implicated. Antineutrophil cytoplasmic
antibodies (ANCAs) and antinuclear antibodies
(ANAs) are principal features of PSC. Of lesser importance
are anticolon epithelial autoantibodies. Incidence
is predominantly male, in contrast to most autoimmune
diseases. Lymphocytes infiltrate and destroy bile ducts.
Hypergammaglobulinanemia, circulatory immune complexes,
increased metabolism of complement component
C3, and classical pathway activation of complement occur.
Primary structure.
primary structure
The linear amino acid sequence of a polypeptide or
protein molecule.