Untitled - D Ank Unlimited

β 1H 106 bifunctional antibodies
1H
Refer to factor H.
-2 glycoprotein-I autoantibodies
Autoantibodies against β-2 glycoprotein-1 (β-2-GP1), a
natural serum coagulation inhibitor. These autoantibodies
represent one of the interactions of antiphospholipid
antibodies with components of the clotting system.
Antiphospholipid autoantibodies occur in antiphospholipid
syndrome (APS), which is associated with
recurrent thrombotic events, repeated fetal loss, and/
or thrombocytopenia, usually associated with systemic
lupus erythematosus (SLE), as well as in patients without
autoimmune disease. β-2-GP1, a 50-kDa plasma
protein binds to phospholipids (PLs) and lipoproteins.
Binding to PLs inhibits the intrinsic blood coagulation
pathway, prothrombinase activity, and ADP-dependent
platelet aggregation and induces a conformational
change in β-2-GP1, causing β-2-GPI autoantibodies to
bind only to β-2-GP1 when it is complexed to PLs.
2 microglobulin ( 2M)
A thymic epithelium-derived polypeptide that is 11.8 kDa
and makes up part of the major histocompatibility complex
(MHC) class I molecules that appear on the surfaces of
nucleated cells. It is noncovalently linked to the MHC class
I polypeptide chain. It promotes maturation of T lymphocytes
and serves as a chemotactic factor. β 2M makes up part
of the peptide–antigen class I–β 2M complex involved in
antigen presentation to cytotoxic T lymphocytes. Nascent
β 2M facilitates the formation of antigenic complexes that
can stimulate T lymphocytes. This monomorphic polypeptide
accumulates in the serum in renal dialysis patients and
may lead to β 2 microglobulin (β 2M) 2-induced amyloidosis.
The extracellular protein β 2M is encoded by a nonpolymorphic
gene outside the MHC. It is homologous structurally to
an immunoglobulin domain and is invariant among all class
I molecules.
-adrenergic receptor autoantibodies
Autoantibodies against β1-adrenoreceptors are
detected in a significant proportion of individuals with
dilated cardiomyopathy. The human heart contains
both β1-adrenoreceptors and a substantial number of
β2-adrenoreceptors. Both types are diminished in chronic
heart failure. β1-adrenoreceptors are decreased in all
types of heart failure, whereas β2-adrenoreceptors are
diminished in mitral valve disease, tetralogy of Fallot, and
end-stage ischemic cardiomyopathy; 30 to 40% of dilated
cardiomyopathy, 22% of ischemic cardiomyopathy, and
25% of alcoholic cardiomyopathy patients develop autoantibodies
against β-adrenoreceptors. In familial, idiopathic,
dilated cardiomyopathy, 62% of affected family members
manifest the β-adrenoreceptor autoantibodies, compared
to 29% in unaffected members. Dilated cardiomyopathy
patients have increased frequency of HLA-DR4 antigen
compared to normal persons, and 60 to 80% of patients
with HLA-DR4 and dilated cardiomyopathy develop
β-adrenoreceptor antibodies.
beta-gamma bridge
Patients with chronic liver disease such as that caused by
alcohol, chronic infection, or connective tissue disease may
synthesize sufficient polyclonal proteins whose electrophoretic
mobilities are in the β–γ range to cause obliteration of
the β and γ peaks, forming a “bridge” from one to the other.
Normal
Albumin Alcoholic
α1 α2 β γ
Beta-gamma bridge.
thromboglobulin (TG)
A chemokine generated through successive proteolysis of
platelet basic protein (PBP), a 94-amino-acid protein present
in the α granules of platelets. The plasma concentrations
of both βTG and PF4 granule constituents are assayed for
platelet activation in allergic states and asthma.
Ernst Beutner.
Beutner, Ernst
A member of the Buffalo Immunology Group.
bevacizumab
A humanized IgG 1 monoclonal antibody that unites with
vascular endothelial growth factor (VEGF) and blocks
VEGF binding to its receptor, mainly on endothelial cells.
It has an antiangiogenic effect, inhibiting blood vessel
growth in tumors. It is used to treat patients with metastatic
colorectal cancer.
BFPR
Abbreviation for biological false-positive reaction.
biclonality
In contrast to uncontrolled proliferation of a single clone
of neoplastic cells which is usually associated with tumors,
rarely two neoplastic cell clones may proliferate simultaneously,
leading to a biclonality. For example, either neoplastic
B or T lymphocytes may demonstrate this effect.
bifunctional antibodies
Artificially formed immunoglobulins that manifest double,
well-defined antigen specificity. They are used to focus the
activity of an effector cell on a target cell by their ability to
bind with one combining site on the effector cell and with
another on the target cell. Antibodies to helper and cytotoxic
effector T cell receptors can mimic antigen and activate the T
cells to proliferate, release lymphokines, or become cytotoxic.