WK 2 Flashcards
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is mediated by various cells of the IS, such as
macrophages, T cells, and dendritic cells,
which function to eliminate viruses, bacteria,
cancer cells, and other cellular pathogens
cellular defense mechanism
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consists of B cells and the specific antibodies
they produce, along with complement
components that are produced in plasma,
saliva, and other bodily secretions.
humoral mechanism
or immunoglobulins, have special significance
for transfusion medicine, because antigens
present on transfused cells may cause
reactions in the recipient and complicate
therapy
Antibodies
Immune response
Immune response
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First step is external, including skin and
enzymes present on the skin’s surface
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Second is internal and can recognize
common invaders with a nonspecific
response
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Last line of defense is the acquired immune
response
prevent infection and damaged cells from
destroying the host
Innate immuniyt
primitive and does not function in a specifc way; rather, it recognizes certain complex repeating patterns present on common invading organisms
Innate immunity
are factors that include antibodies
and complement components in plasma that
coat pathogens and facilitate phagocytosis
Opsonins
soluble polypeptide substances
help to regulate the immune response in
terms of specificity, intensity, and duration
Cytokines
Two major cells that can use phagocytosis to
remove pathogens are the
polymorphonuclear cells (which include
neutrophils, basophils, and eosinophils) and
the mononuclear cells (which include the
monocytes in plasma
Relies on the formation of specific
antigen-antibody complexes and specific
cellular responses.
Cquired immunity
An antigen that an antibody is made against
is sometimes referred to as its
antithetical
antigen
play a critical role in
cellular immunity by activating and
deactivating different cells, and allowing cells
to communicate throughout the host body
Cellular immuniy
consists of the fluid parts of the IS, such as
antibodies and complement components
found in plasma, saliva, and other secretions
Humoral immunity
relies on
the detection of antibodies (and complement)
bound to the surface of RBCs.
direct antiglobulin (Coombs) test
These cell surface molecules specify cellular
definitions and functions, including maturation
levels and lineage specificity
clusters of differentiation (CD) markers
These cell surface molecules specify cellular
definitions and functions, including maturation
levels and lineage specificity
clusters of differentiation (CD) markers
Happens where an antigen is recognized by
more than one antibody,in which the different
cells that recognize the different epitopes of
the antigen are expanded.
clonal selection
Plasma cells are antibody factories that
make large amounts of one specific type of
antibody in a soluble form that remains in
circulation in the plasma, body secretions,
and lymphatic system
B cells
recognize antigens that are internalized within
a host cell
Tncells
T cells require this to help identify foreign antigen
Majr histocompatilibiloy complex (MHC)
s determine the human leukocyte
antigens (HLA) present on leukocytes and
other cells.
MHC gene
are a major determinant of
tissue graft rejection
HLA molecules
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important in the recognition of foreign
substances and the immune reactions
against them
MHC I AND II
Two major functions of T cells.
- to produce immune mediating substances
such as cytokines, which influence many
immune functions throughout the body. - to kill cells that contain foreign antigen
2 types of T cell
I
- TH CELLS - CD8 - MHC I
- TC CELLS - CD4 - MHC II
ability to recognize antigen, along with
MHC class II molecules, and provide help
to B cells to evolve into plasma cells and
make antibodies
TH CELLS
phagocytize the foreign antigen, process it internally, and then with the help of MHC molecules, present short peptide sequences
Antigen presenting cell
during this time that antibody cannot be
detected with serologic testing
latency, pre-seroconversion, or window period
critical to identifying hematopoietic cell
maturation stages and lineages
critical to identifying hematopoietic cell
maturation stages and lineages
Cd markers interact directly to
And indirectly by
Macrophages, NK cells, T and B cells, and
APCs can interact directly with cell-to-cell
communication or indirectly with soluble
mediators through a complex system
All immune cells originate from ________through one of two pathways of lineage,
the _______or the _______
All immune cells originate from pluripotent
hematopoietic progenitors (or CD34-positive
cells) through one of two pathways of lineage,
the myeloid or the lymphoid
consist of phagocytic cells such as the monocytes and macrophages, often referred to as the mononuclear phagocytic system (MPS); the granulocytes or
polymorphonuclear cells (PMNs), the neutrophils, eosinophils, and the basophils; and the APCs such as the dendritic cells in the skin and liver.
Myeloid lineage
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lymphoid lineage consists of the various
subpopulations of lymphoid cells, the T cells,
B cells, and NK cells.
LYMPHOID LINEAGE
cells present antigen to lymphocytes
and interact with other immune cells via cell
membrane receptors
MPS
possess high-affinity FC immunoglobulin E
(IgE) receptors, are powerful effectors of
inflammation and allergic reactions, and can
cause the release of localized histamine
basophils and mast cells
to interact with antigens and to differentiate
between self and nonself antigens
lymphocytes
involved in cell adhesion. It has the
unique ability to bind with sheep erythrocytes
in vitro
CD2 MARKER
can stimulate multiple T cells, causing
them to release large amounts of
cytokines
superantigens
Membrane-bound immunoglobulin may act as
an antigen receptor for binding simple
structural antigens or antigens with multiple
repeating determinants
T cell–independent antigens
When B cells require the intervention of T cells to
assist in the production of antibody
T cell–dependent antigens
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large granular lymphocytes who do not have surface Ig or secrete Ig, nor do
they have antigen receptors like the TCR of T
cell
NK CELLS
thymus-independent and are able to lyse virally infected cells and tumor cells directly in via (ADCC) by anchoring immunoglobulin to the cell surface membrane through an FC recep
Nk cells
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The lack of these antigens can
prevent certain types of malaria
parasites from infecting the host.
Duffy antigen group
may also modulate
immune response by acting as a sink
for extra cytokines of the IL-8 family
Duffy antigen
are found on all
nucleated cells except trophoblasts and sperm, and they play a key role in cytotoxic
T-cell function
MHC CLASS 1
are found on
antigen-presenting cells such as B
lymphocytes, activated T cells, and the
various dendritic cells
Class II molecules
on APCs are essential for presenting processed antigen to CD4 T cells and are necessary for T-cell functions
and B-cell help.
Class II molecules
Class III molecules that encode
complement components such as C2, C4,
and factor B
MHC CLASS III
The genes for MHC classes I through III molecules
are located on the short arm of________^ and
are highly polymorphic in nature with multiple
alleles.
chromosome 6
Immunoglobulins are classified according to
the molecular structure of their
heavy
chains.
two types of light chains:
κ (kappa) and λ
(lambda)
________ holds the light and heavy chains together, and the _____in Ig molecules provide greater structural strength than do hydrogen bonding and van der Waals forces.
covalent disulfide bonding holds the light
and heavy chains together, and the covalent
disulfide linkages in Ig molecules provide
greater structural strength than do hydrogen
bonding and van der Waals forces.
Most clinically significant antibodies that react
at body temperature (37°C)
IgG
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are capable of destroying transfused
antigen-positive RBCs, causing anemia and
transfusion reactions of various severities.
IgG
Immunoglobuin that are most commonly
encountered as naturally occurring antibodies
in the ABO system
IgM
are believed to be produced in response to
commonly occurring antigens such as
intestinal flora and pollen grains
IgM
Other blood groups such as Lewis, Ii, P, and
MNS may also produce IgM antibodies, which
usually react best at ambient temperature
IgM
can cause severe
anaphylaxis if IgA are transfused in plasma
products to patients who are deficient in
IgA.
anti-IgA antibodies
can increase the effect of IgG-induced
RBC hemolysis.
IgA
