Technology
Radioimmunoassay
Radioimmunoassay (RIA) is an immunological technique, which quantitatively determines antigen and antibody concentrations, using a radioactively labeled substance (radioligand), either directly or indirectly.
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Technology
Radioimmunoassay (RIA) is an immunological technique, which quantitatively determines antigen and antibody concentrations, using a radioactively labeled substance (radioligand), either directly or indirectly.
Glossary Term
A type of protein made by B lymphocytes in response to a foreign substance (antigen). Each antibody only binds to a specific antigen, helping to destroy the antigen directly or by assisting white blood cells to destroy the antigen.
Indicators
An autoantibody that recognizes antigens found in the cytoplasm of neutrophils.
Glossary Term
Strength of binding, usually of a small molecule with multiple binding sites by a larger, particularly the binding of a complex antigen by an antibody.
Tests
Clinical laboratory tests that detect and identify the antigens expressed by red blood cells to determine a subject's blood type.
Tests
An immunoassay that detects bladder cancer antigen, which is comprised of various members of the complement factor H-related protein (CFHrp) family, in urine.
Tests
A CA 19-9 test measures the amount of a protein called CA 19-9 (cancer antigen 19-9) in a sample of your blood. CA 19-9 is a type of tumor marker. Tumor markers are substances made by cancer cells or by normal cells in response to cancer .
Tests
This test measures the amount of a protein called CA-125 (cancer antigen 125) in a sample of your blood. CA-125 is a type of tumor marker. Tumor markers are substances that are often made by cancer cells or by normal cells in response to cancer.
Indicators
A protein complex comprised of one T-cell surface glycoprotein CD3 delta chain (CD3D), one T-cell surface glycoprotein CD3 gamma chain (CD3G) and two T-cell surface glycoprotein CD3 epsilon chains (CD3E). CD3D, CD3G and CD3E are transmembrane proteins with one extracellular immunoglobulin domain and one intracellular ITAM domain. The CD3 complex is a T-cell co-receptor that noncovalently associates with either the disulfide bound heterodimeric alpha/beta T-cell receptor (TCR) or gamma/delta TCR and two copies of the accessory protein, T-cell surface glycoprotein CD3 zeta chain (CD247), which is a transmembrane protein with three ITAM domains. The TCR moiety of the TCR-CD3 complex binds to MHC and processed antigens on antigen presenting cells, which triggers phosphorylation of and cellular propagation of the signal by CD247 and the CD3 complex.
Tests
A laboratory blood test to measure carcinoembryonic antigen (CEA), a protein found in many types of cells, but is associated with tumors. Used as a tumor marker.
Indicators
A protein complex composed of 18 complement component 1q (C1q) subcomponent chains: six C1qA, six C1qB and six C1qC. The C1q complex is part of the complement component C1 complex (C1 complex) and undergoes confirmational rearrangement following binding of pentraxins or antigen-antibody complexes that include either immunoglobulin M (IgM) or several IgG molecules. These confirmational changes activate the C1r chains of the C1 complex, which, in turn, cleaves C1s chains of the C1 complex. Following C1s cleavage, the C1 complex can proteolytically activate C2 and C4 and promotes formation of C3-convertase, which cleaves C3 and activates the classical complement pathway.
Indicators
Complement component-4 (1744 aa, ~193 kDa) is part of the complement cascade, which mediates the innate immune response to infection. The full length protein is a precursor that is secreted as a trimeric molecule containing an alpha, beta and gamma chain. When the complement cascade is initiated, the protein is cleaved. This proteolysis releases both the alpha chain, C4 anaphylatoxin, which stimulates inflammation, and a dimer of the beta and gamma chains, which mediates the interaction between the antigen-antibody complex and other complement components.