Structural insights into C3 convertase activity of the classical pathway of complement [PDF]
Nature CommunicationsImmune protection by the complement system depends on C3 cleavage by C3 convertases that is critical to all three activation pathways. Structural data on convertase formation in the classical pathway and on C3-substrate binding to convertases is lacking.
Karla I. De la O Becerra +3 more
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Clinical features of patients with homozygous complement C4A or C4B deficiency.
PLoS ONE, 2018 IntroductionHomozygous deficiencies of complement C4A or C4B are detected in 1-10% of populations. In genome-wide association studies C4 deficiencies are missed because the genetic variation of C4 is complex.
Inka Liesmaa +4 more
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Human pentraxin 3 binds to the complement regulator c4b-binding protein.
PLoS ONE, 2011 The long pentraxin 3 (PTX3) is a soluble recognition molecule with multiple functions including innate immune defense against certain microbes and the clearance of apoptotic cells.
Anne Braunschweig, Mihály Józsi
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Significance of urine complement proteins in monitoring lupus activity [PDF]
PeerJ, 2022 Objectives Complement activation is a critical feature in the development of systemic lupus erythematosus (SLE). Whether there are changes of complement components in the urine of SLE has not been reported.
Jin Zhao +5 more
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Structure-Based Modeling of Complement C4 Mediated Neutralization of Adenovirus
Viruses, 2021 Adenovirus (AdV) infection elicits a strong immune response with the production of neutralizing antibodies and opsonization by complement and coagulation factors.
Corey C. Emerson, Phoebe L. Stewart
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The fc fragment of IgMs binds C1q to activate the first step of the classical complement pathway, while inhibiting complement-dependent cytotoxicity. [PDF]
FEBS JMultimeric IgM‐fragment crystallizable region (Fc) fragments retain the ability to bind C1q and initiate the classical complement pathway, leading to C4 activation and deposition in vitro. However, the Fc cores can also inhibit complement‐dependent cytotoxicity by competing with surface‐bound antibodies for C1q engagement.
Pinto AJ +9 more
europepmc +2 more sources
Frontiers in Cellular Neuroscience, 2023 Complement system plays an important role in the immune defense against pathogens; however, recent studies demonstrated an important role of complement subunits C1q, C4, and C3 in normal functions of the central nervous system (CNS) such as non ...
Tatyana Veremeyko +8 more
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Acquisition of complement inhibitor serine protease factor I and its cofactors C4b-binding protein and factor H by Prevotella intermedia. [PDF]
PLoS ONE, 2012 Infection with the Gram-negative pathogen Prevotella intermedia gives rise to periodontitis and a growing number of studies implies an association of P. intermedia with rheumatoid arthritis.
Sven Malm +5 more
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Complement c4b–null alleles in felty's syndrome [PDF]
Arthritis & Rheumatism, 1988 AbstractC4A and C4B allotypes were compared in 20 patients with Felty's syndrome (FS), 52 patients with rheumatoid arthritis (RA), and 55 control subjects. Nineteen of the FS patients had HLA–DR4. A C4B‐null allele was more frequent in the patients with FS (60%) than in either the RA patients (15%) or the control subjects (26%).
W, Thomson +5 more
openaire +2 more sources
Diagnostics, 2021 The role and diagnostic value of the synovial complement system in patients with low-grade periprosthetic joint infection (PJI) are unclear. We sought to evaluate, for the first time, the usefulness of synovial complement factors in these patients by ...
Frank Sebastian Fröschen +6 more
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