Biomaterial Database

C3 metabolism in a patient with deficiency of the second component of complement (C2) and discoid lupus erythematosus. 1976

J H Wild, and N J Zvaifler, and H J Müller-Eberhard, and C B Wilson

A patient with a hereditary deficiency of the second component of complement and discoid lupus erythematosus with features of systemic lupus erythematosus was studied. The propositus had a 9-year history of rash and arthralgia. Transient renal disease had completely resolved; there was a history of seizures. Examination of his serum disclosed antinuclear antibodies but no total haemolytic complement activity. C2 was absent. Serum concentrations of C1s, C3, C5 and C9 were elevated; other complement components were present in normal concentration, including C3 pro-activator. The patient's C3 pro-activator was electrophoretically converted by inulin and four of five lipopolysaccharides, but was poorly converted by aggregated human IgG. Two separate turnover studies with radiolabelled C3 showed fractional catabolic rates of 3-03 and 2-48% of the remaining plasma pool/hr (range of three normals: 1-62-2-18%/hr); and estimated C3 synthetic rates of 2-74 and 2-31 mg/kg/hr (range of three normals: 0-89-1-40 mg/kg/hr). Serum complement profiles of the patient's family demonstrated that the C2 deficiency was inherited as an autosomal codominant. One sibling, homozygous for C2 deficiency, and three other siblings, both parents and one daughter, all heterozygous for C2 deficiency, are in good health. Immunofluorescent studies of the patient's diseased skin exhibited substantial deposits of IgG, IgM, C1q, and C4 but not of later acting complement components, properdin, or C3 proactivator. These studies do not support the notion that inflammation in C3-deficient individuals with lupus erythematosus is mediated by the alternative complement pathway.

UI	MeSH Term	Description	Entries
D007074	Immunoglobulin G	The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.	Gamma Globulin, 7S,IgG,IgG Antibody,Allerglobuline,IgG(T),IgG1,IgG2,IgG2A,IgG2B,IgG3,IgG4,Immunoglobulin GT,Polyglobin,7S Gamma Globulin,Antibody, IgG,GT, Immunoglobulin
D007153	Immunologic Deficiency Syndromes	Syndromes in which there is a deficiency or defect in the mechanisms of immunity, either cellular or humoral.	Antibody Deficiency Syndrome,Deficiency Syndrome, Immunologic,Deficiency Syndromes, Antibody,Deficiency Syndromes, Immunologic,Immunologic Deficiency Syndrome,Immunological Deficiency Syndromes,Antibody Deficiency Syndromes,Deficiency Syndrome, Antibody,Deficiency Syndrome, Immunological,Deficiency Syndromes, Immunological,Immunological Deficiency Syndrome,Syndrome, Antibody Deficiency,Syndrome, Immunologic Deficiency,Syndrome, Immunological Deficiency,Syndromes, Antibody Deficiency,Syndromes, Immunologic Deficiency,Syndromes, Immunological Deficiency
D008179	Lupus Erythematosus, Discoid	A chronic form of cutaneous lupus erythematosus (LUPUS ERYTHEMATOSUS, CUTANEOUS) in which the skin lesions mimic those of the systemic form but in which systemic signs are rare. It is characterized by the presence of discoid skin plaques showing varying degrees of edema, erythema, scaliness, follicular plugging, and skin atrophy. Lesions are surrounded by an elevated erythematous border. The condition typically involves the face and scalp, but widespread dissemination may occur.	Lupus Erythematosus, Chronic Cutaneous,Lupus Erythematosus, Cutaneous, Chronic,Discoid Lupus Erythematosus
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D010375	Pedigree	The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.	Family Tree,Genealogical Tree,Genealogic Tree,Genetic Identity,Identity, Genetic,Family Trees,Genealogic Trees,Genealogical Trees,Genetic Identities,Identities, Genetic,Tree, Family,Tree, Genealogic,Tree, Genealogical,Trees, Family,Trees, Genealogic,Trees, Genealogical
D003165	Complement System Proteins	Serum glycoproteins participating in the host defense mechanism of COMPLEMENT ACTIVATION that creates the COMPLEMENT MEMBRANE ATTACK COMPLEX. Included are glycoproteins in the various pathways of complement activation (CLASSICAL COMPLEMENT PATHWAY; ALTERNATIVE COMPLEMENT PATHWAY; and LECTIN COMPLEMENT PATHWAY).	Complement Proteins,Complement,Complement Protein,Hemolytic Complement,Complement, Hemolytic,Protein, Complement,Proteins, Complement,Proteins, Complement System
D003169	Complement Inactivator Proteins	Serum proteins that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host. The complement system is tightly regulated by inactivators that accelerate the decay of intermediates and certain cell surface receptors.	Complement Cytolysis Inhibiting Proteins,Complement Cytolysis Inhibitor Proteins,Complement Inactivating Proteins,Serum Complement Inactivators,Complement Inactivators, Serum,Inactivating Proteins, Complement,Inactivator Proteins, Complement,Inactivators, Serum Complement,Proteins, Complement Inactivating,Proteins, Complement Inactivator
D003175	Complement C2	A component of the CLASSICAL COMPLEMENT PATHWAY. C2 is cleaved by activated COMPLEMENT C1S into COMPLEMENT C2B and COMPLEMENT C2A. C2a, the COOH-terminal fragment containing a SERINE PROTEASE, combines with COMPLEMENT C4B to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).	C2 Complement,Complement 2,Complement Component 2,C2, Complement,Complement, C2,Component 2, 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