Biomaterial Database

Relative importance of C3b inactivator and beta 1H globulin in the modulation of the properdin amplification loop in systemic lupus erythematosus. 1979

K Whaley, and P H Schur, and S Ruddy

Serum concentrations of C4, C3, factor B (B), properdin (P), C3b inactivator (C3bINA) and beta 1H globulin have been measured by radial immunodiffusion in sixty-two samples from thirteen patients with systemic lupus erythematosus (SLE). Significant reductions in the mean serum concentrations of C4 (classical pathway) B and P (alternative pathway) and C3 were found. In addition, the mean level of the control protein beta 1H, but not C3bINA, was reduced. Sera from thirteen patients taking during disease exacerbation (low C3) showed significantly lower levels of both C3bINA and beta 1H than sera taken from the same thirteen patients during disease remission (high C3). Serum concentrations of C3bINA correlated with B (P less than 0.005) but not C4, C3 or P, whereas levels of beta 1H correlated with C4 (P less than 0.01), B (P less than 0.005) and properdin (P less than 0.01). Serial measurements of the serum concentrations of C3bINA and beta 1H showed that levels of these protein fell during exacerbation, and such falls were more closely associated with diseases in the serum levels of the alternative pathways proteins than C4. It is concluded from these observations that serum concentrations of the control proteins C3bINA and beta 1H, especially the latter, control the extent of turnover of the alternative pathway in SLE. Metabolic studies are required to determine the causes of the decreased serum concentrations of these control proteins.

UI	MeSH Term	Description	Entries
D008180	Lupus Erythematosus, Systemic	A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.	Libman-Sacks Disease,Lupus Erythematosus Disseminatus,Systemic Lupus Erythematosus,Disease, Libman-Sacks,Libman Sacks Disease
D011414	Properdin	A 53-kDa protein that is a positive regulator of the alternate pathway of complement activation (COMPLEMENT ACTIVATION PATHWAY, ALTERNATIVE). It stabilizes the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) and protects it from rapid inactivation, thus facilitating the cascade of COMPLEMENT ACTIVATION and the formation of MEMBRANE ATTACK COMPLEX. Individuals with mutation in the PFC gene exhibit properdin deficiency and have a high susceptibility to infections.	Complement Factor P,Factor P, Complement
D011415	Complement Factor B	A glycine-rich, heat-labile serum glycoprotein that contains a component of the C3 CONVERTASE ALTERNATE PATHWAY (C3bBb). Bb, a serine protease, is generated when factor B is cleaved by COMPLEMENT FACTOR D into Ba and Bb.	C3 Proactivator,C3PA,Complement 3 Proactivator,Factor B,Properdin Factor B,Bb Fragment of Factor B,Complement Factor B Fragment, Bb,Complement Factor B, Alternative Pathway,Complement Factor B-Derived Fragment Bb,Complement Factor Ba,Complement Factor Bb,Complement Protein B,Complement Protein Factor B,Properdin Factor Ba,Properdin Factor Bb,Properdin Factor Bf,Properdin Factor Bf F1,Bb, Complement Factor,Complement Factor B Derived Fragment Bb,Factor B, Complement,Factor B, Properdin,Factor Ba, Complement,Factor Ba, Properdin,Factor Bb, Complement,Factor Bb, Properdin,Factor Bf, Properdin,Proactivator, C3,Proactivator, Complement 3,Protein B, Complement
D012075	Remission, Spontaneous	A spontaneous diminution or abatement of a disease over time, without formal treatment.	Spontaneous Healing,Spontaneous Regression,Spontaneous Remission,Healing, Spontaneous,Regression, Spontaneous,Spontaneous Healings,Spontaneous Regressions
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
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
D003180	Complement C3b Inactivator Proteins	Endogenous proteins that inhibit or inactivate COMPLEMENT C3B. They include COMPLEMENT FACTOR H and COMPLEMENT FACTOR I (C3b/C4b inactivator). They cleave or promote the cleavage of C3b into inactive fragments, and thus are important in the down-regulation of COMPLEMENT ACTIVATION and its cytolytic sequence.	C3b Inactivators,C3b Inhibitors,Complement 3b Inactivators,Complement 3b Inhibitors,Complement C3b Inactivators,Complement C3b Inhibitor Proteins,Conglutinogen Activating Factors,Factors, Conglutinogen Activating,Inactivators, C3b,Inactivators, Complement 3b,Inactivators, Complement C3b,Inhibitors, C3b,Inhibitors, Complement 3b
D003181	Complement C4	A glycoprotein that is important in the activation of CLASSICAL COMPLEMENT PATHWAY. C4 is cleaved by the activated COMPLEMENT C1S into COMPLEMENT C4A and COMPLEMENT C4B.	C4 Complement,C4 Complement Component,Complement 4,Complement C4, Precursor,Complement Component 4,Pro-C4,Pro-complement 4,C4, Complement,Complement Component, C4,Complement, C4,Component 4, Complement,Component, C4 Complement,Pro C4,Pro complement 4
D005779	Immunodiffusion	Technique involving the diffusion of antigen or antibody through a semisolid medium, usually agar or agarose gel, with the result being a precipitin reaction.	Gel Diffusion Tests,Diffusion Test, Gel,Diffusion Tests, Gel,Gel Diffusion Test,Immunodiffusions,Test, Gel Diffusion,Tests, Gel Diffusion