Untitled - D Ank Unlimited

persistent generalized lymphadenopathy (PGL) 567 PF-4 (platelet factor 4)
molecules to tissues containing collagen. Thereafter, the
primary rabbit antibody against the antigen to be identified
is reacted with the tissue section. Unbound primary
antibody is removed by rinsing the sections that are then
covered with swine antibody against rabbit immunoglobulin.
This so-called linking antibody will combine with any
primary rabbit antibody in the tissue. It is added in excess.
As a result, one of its antigen-binding sites remains free.
After washing, the PAP is placed on the section, and the
antibody portion of this complex raised in rabbits will
be bound to the free antigen-binding site of the linking
antibody on the sections. The inbound PAP complex is
then washed away by rinsing. To read the sections microscopically
it is necessary to add a substrate of hydrogen
peroxide and aminoethylcarbazole (AEC) that permits
formation of a visible product that may be detected with a
light microscope. The AEC is oxidized to produce a
reddish-brown pigment that is not water-soluble.
Peroxidase catalyzes the reaction. Because peroxidase
occurs only at sites where the PAP is bound via linking
antibody and primary antibody to antigen molecules, the
antigen is identified by the reddish-brown pigment. The
tissue section can then be counterstained with hematoxylin
or other suitable dye, covered with mounting medium
and cover slips, and read by conventional light microscopy.
The PAP technique has been replaced, in part, by
the avidin–biotin complex (ABC) technique.
persistent generalized lymphadenopathy (PGL)
A clinical stage of HIV infection.
persistent infection
The prolonged existence of a pathogenic microorganism in
the host body, which may be throughout life. Infections of
this type may be latent or induced chronic diseases.
pertussis adjuvant
Killed Bordetella pertussis microorganisms mixed with
antigen to enhance antibody production. Pertussis adjuvant
particularly facilitates immunoglobulin E (IgE) synthesis
in rats and other animals. When used as a component in
the triple vaccine (diphtheria–pertussis–tetanus [DPT])
preparation used for childhood immunization, the killed B.
pertussis microorganisms stimulate antibodies that protect
against whooping cough and also facilitate antibody synthesis
against both the diphtheria and tetanus toxoid preparations,
thereby serving as an immunologic adjuvant.
Pertussis Vaccine
Risk of Occurrence After
Problem Vaccination Disease
Seizure 1:1750 1:25–1:50
Encephalitis 1:100,000 1:1000–1:4000
Severe brain damage 1:310,000 1:2000–1:8000
Death 1:1,000,000 1:200–1:1000
pertussis vaccine
A preparation used for prophylactic immunization against
whooping cough in children. It consists of virulent
Bordetella pertussis microorganisms killed by treatment
with formalin. It is administered in conjunction with
diphtheria toxoid and tetanus toxoid as a so-called triple
vaccine. In addition to stimulating protective immunity
against pertussis, the killed B. pertussis microorganisms act
as an adjuvant and facilitate antibody production against the
diphtheria and tetanus toxoid components in vaccine. Rarely
does a hypersensitivity reaction occur. To reduce the toxic
effects of the vaccine, an acellular product is now in use.
Mucosa of ileum with Peyer’s patch.
Peyer’s patch.
Peyer’s patches
Secondary gut-associated lymphoid tissue in the small
intestinal wall, particularly the ileum. Sites where immune
responses to ingested antigens may be induced. They are
composed of lymphocytes, plasma cells, germinal centers,
and thymus-dependent areas.
PF-4 (platelet factor 4)
Platelet factor 4 is a chemokine of the α (CXC) family. It is
a heat-stable, heparin-binding protein stored with fibronectin,
fibrinogen, thrombospondin, von Willebrand factor, and
β-thromboglobulin (β-TG) in the α granules of platelets. PF-4
is secreted from stimulated and aggregated platelets. It is a
megakaryocyte differentiation marker and a negative autocrine
regulator of human megakaryocytopoiesis. A related protein
called low affinity platelet factor 4 (LAPF-4) shares 50%
homology with PF-4 but, unlike PF-4, is an active mitogenic
and chemotactic agent that fails to bind heparin. PF4 interacts
with a carrier molecule, a 53-kDa proteoglycan, in vivo.
P