Biomaterial Database

Failure of IgA cold agglutinin to activate C. 1980

W Römer, and U Rother, and D Roelcke

No complement (C) activation was observed when IgA cold agglutinin was reacted with its antigen on RBC. Neither C-consumption (CH50) nor C1 binding (classical pathway) nor conversion of factor B or C3 (alternative pathway) could be detected. In contrast, IgM cold agglutinins under the same conditions did activate the classical pathway. If the IgA was heat aggregated it was able to activate the alternative pathway as evidenced by factor B and C3 conversion. The result is consistent with the absence of in vivo hemolysis in patients with IgA cold agglutinins.

UI	MeSH Term	Description	Entries
D007070	Immunoglobulin A	Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) is the main immunoglobulin in secretions.	IgA,IgA Antibody,IgA1,IgA2,Antibody, IgA
D007075	Immunoglobulin M	A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally was called a macroglobulin.	Gamma Globulin, 19S,IgM,IgM Antibody,IgM1,IgM2,19S Gamma Globulin,Antibody, IgM
D007123	Immunoelectrophoresis, Two-Dimensional	Immunoelectrophoresis in which a second electrophoretic transport is performed on the initially separated antigen fragments into an antibody-containing medium in a direction perpendicular to the first electrophoresis.	Immunoelectrophoresis, Crossed,Immunoelectrophoresis, 2-D,Immunoelectrophoresis, 2D,2-D Immunoelectrophoresis,2D Immunoelectrophoresis,Crossed Immunoelectrophoresis,Immunoelectrophoresis, 2 D,Immunoelectrophoresis, Two Dimensional,Two-Dimensional Immunoelectrophoresis
D010265	Paraproteinemias	A group of related diseases characterized by an unbalanced or disproportionate proliferation of immunoglobulin-producing cells, usually from a single clone. These cells frequently secrete a structurally homogeneous immunoglobulin (M-component) and/or an abnormal immunoglobulin.	Gammapathy, Monoclonal,Gammopathy, Monoclonal,Monoclonal Gammopathies,Paraimmunoglobulinemia,Paraimmunoglobulinemias,Paraproteinemia,Plasma Cell Dyscrasias,Monoclonal Gammapathies,Monoclonal Gammopathy,Cell Dyscrasia, Plasma,Dyscrasia, Plasma Cell,Monoclonal Gammapathy,Plasma Cell Dyscrasia
D003167	Complement Activation	The sequential activation of serum COMPLEMENT PROTEINS to create the COMPLEMENT MEMBRANE ATTACK COMPLEX. Factors initiating complement activation include ANTIGEN-ANTIBODY COMPLEXES, microbial ANTIGENS, or cell surface POLYSACCHARIDES.	Activation, Complement,Activations, Complement,Complement Activations
D003170	Complement Pathway, Alternative	Complement activation initiated by the interaction of microbial ANTIGENS with COMPLEMENT C3B. When COMPLEMENT FACTOR B binds to the membrane-bound C3b, COMPLEMENT FACTOR D cleaves it to form alternative C3 CONVERTASE (C3BBB) which, stabilized by COMPLEMENT FACTOR P, is able to cleave multiple COMPLEMENT C3 to form alternative C5 CONVERTASE (C3BBB3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.	Alternative Complement Pathway,Properdin Pathway,Alternative Complement Activation Pathway,Complement Activation Pathway, Alternative
D003171	Complement Pathway, Classical	Complement activation initiated by the binding of COMPLEMENT C1 to ANTIGEN-ANTIBODY COMPLEXES at the COMPLEMENT C1Q subunit. This leads to the sequential activation of COMPLEMENT C1R and COMPLEMENT C1S subunits. Activated C1s cleaves COMPLEMENT C4 and COMPLEMENT C2 forming the membrane-bound classical C3 CONVERTASE (C4B2A) and the subsequent C5 CONVERTASE (C4B2A3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.	Classical Complement Pathway,Classical Complement Activation Pathway,Complement Activation Pathway, Classical
D003172	Complement C1	The first complement component to act in the activation of CLASSICAL COMPLEMENT PATHWAY. It is a calcium-dependent trimolecular complex made up of three subcomponents: COMPLEMENT C1Q; COMPLEMENT C1R; and COMPLEMENT C1S at 1:2:2 ratios. When the intact C1 binds to at least two antibodies (involving C1q), C1r and C1s are sequentially activated, leading to subsequent steps in the cascade of COMPLEMENT ACTIVATION.	C1 Complement,Complement 1,Complement Component 1,C1, Complement,Complement, C1,Component 1, Complement
D003176	Complement C3	A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. The smaller fragment C3a is an ANAPHYLATOXIN and mediator of local inflammatory process. The larger fragment C3b binds with C3 convertase to form C5 convertase.	C3 Complement,C3 Precursor,Complement 3,Complement C3 Precursor,Complement Component 3,Precursor-Complement 3,Pro-C3,Pro-Complement 3,C3 Precursor, Complement,C3, Complement,Complement, C3,Component 3, Complement,Precursor Complement 3,Precursor, C3,Precursor, Complement C3,Pro C3,Pro Complement 3
D003450	Cryoglobulins	Abnormal immunoglobulins, especially IGG or IGM, that precipitate spontaneously when SERUM is cooled below 37 degrees Celsius. It is characteristic of CRYOGLOBULINEMIA.	Cryoglobulin,Cryoprotein,Cryoproteins