Complement C3b (C3bi)

The larger fragment generated from the cleavage of COMPLEMENT C3 by C3 CONVERTASE. It is a constituent of the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb), and COMPLEMENT C5 CONVERTASES in both the classical (C4b2a3b) and the alternative (C3bBb3b) pathway. C3b participates in IMMUNE ADHERENCE REACTION and enhances PHAGOCYTOSIS. It can be inactivated (iC3b) or cleaved by various proteases to yield fragments such as COMPLEMENT C3C; COMPLEMENT C3D; C3e; C3f; and C3g.

Also Known As:

Networked: 199 relevant articles (4 outcomes, 13 trials/studies)

Relationship Network

Bio-Agent Context: Research Results

Experts

1.	Yan, Jun: 6 articles (06/2013 - 12/2003)
2.	Zhu, Xi-Chen: 4 articles (08/2022 - 01/2017)
3.	Dai, Wen-Zhuo: 3 articles (08/2022 - 12/2020)
4.	Ma, Tao: 3 articles (08/2022 - 12/2020)
5.	Morgan, B Paul: 3 articles (01/2022 - 01/2012)
6.	Allendorf, Daniel J: 3 articles (06/2005 - 12/2003)
7.	Baran, Jarek T: 3 articles (06/2005 - 12/2003)
8.	Cheung, Nai-Kong V: 3 articles (06/2005 - 05/2002)
9.	Hansen, Richard D: 3 articles (06/2005 - 12/2003)
10.	Ross, Gordon D: 3 articles (06/2005 - 12/2003)

Related Diseases

1.	Hemolysis 11/01/2014 - "CRIg-L-FH, slightly more potent than CRIg-FH, considerably inhibited both AP- and also classical pathway (CP)-mediated hemolysis and successfully eliminated the deposition of C3b/iC3b. " 03/18/2010 - "With a goal of improving PNH therapy, we characterized the activity of anti-C3b/iC3b monoclonal antibody 3E7 in an in vitro model of APC-mediated hemolysis. " 01/01/2019 - "Results reveal that all liposomes studied, caused minimum hemolysis; targeted liposomes slightly reduced blood coagulation time, but not significantly more than control liposomes; and compliment factors SC5b9 and iC3b increased when compared with the buffer, by most targeted liposomes. " 01/01/2017 - "GPI-defective erythrocytes, being protected from intravascular hemolysis by eculizumab, accumulate C3-derived fragments, C3b, iC3b, and C3dg, because of DAF deficiency and in turn become susceptible to CR3-mediated phagocytosis by spleen macrophages. " 01/01/2013 - "More intriguingly, a human fusion protein consisting of the iC3b/ C3d-binding region of complement receptor 2 and of the inhibitory domain of the CAP regulator factor H has been recently shown effective in inhibiting, in vitro, both intravascular hemolysis of and surface C3-deposition on PNH erythrocytes, and is now under investigation in phase 1 clinical trials."
2.	Inflammation (Inflammations) 01/01/2023 - "This demonstrates that noninvasive imaging with an anti-iC3b/C3d probe can be used to monitor inflammation in the kidneys." 02/01/2013 - "Complement component 3b (C3b), a marker of acute inflammation, was not significantly altered. " 11/22/2011 - "We establish herein that cell contact-mediated nTreg regulatory function is inhibited by inflammation, especially in the presence of the complement C3b receptor (CD46). " 08/09/2011 - "iC3b then interacts with the complement receptors (CR) of the Ig superfamily, CR2 (CD21), CR3 (CD11b/CD18), and CR4 (CD11c/CD18) on leukocytes, down-modulating inflammation, enhancing B cell-mediated immunity, and targeting pathogens for clearance by phagocytosis. " 05/01/1996 - "The deposition was enhanced in relation to the severity of mucosal inflammation (C3b, P less than 0.05; iC3b/C3dg, P less than 0.01). "
3.	Adenocarcinoma 02/01/2010 - "Soluble iC3b as an early marker for pancreatic adenocarcinoma is superior to CA19.9 and radiology."
4.	Systemic Lupus Erythematosus (Libman-Sacks Disease) 12/01/2009 - "Impaired C3b/iC3b deposition on Streptococcus pneumoniae in serum from patients with systemic lupus erythematosus." 10/01/1989 - "The clinical significance of iC3b neoantigen expression in plasma from patients with systemic lupus erythematosus." 10/14/1982 - "The erythrocytes of patients with systemic lupus erythematosus have been shown to have a decreased number of receptors for the major cleavage fragment of the third component of complement (C3b). " 03/01/1987 - "Studies on human blood lymphocytes with iC3b (type 3) complement receptors: III. Abnormalities in patients with active systemic lupus erythematosus." 01/01/2020 - "Furthermore, with the use of the assay for human C3 fragments, we observed that patients with systemic lupus erythematosus (SLE) (n = 144) had significantly higher iC3b/C3dg levels as compared to healthy individuals (n = 144) (p < 0.0001). "
5.	Burns 06/01/1988 - "In contrast, burn patient neutrophils expressed normal levels of class I HLA molecules and the C3bi receptor. " 08/01/1999 - "Flow cytometric analysis (FCM) was used to study PMLs expression of IgG Fc-receptor III (Fc gamma RIII) as well as the complement receptors CR1 (receptor for C3b) and CR3 (receptor for C3bi) in 23 patients with large burns. " 02/01/1994 - "We have used flow cytometric analysis (FCM) to longitudinally study PMNL expression of IgG Fc-receptor II (Fc gamma RII) and Fc-receptor III (Fc gamma RIII), as well as the complement receptors CR1 (receptor for C3b) and CR3 (receptor for C3bi) in 22 patients with large burns. "

Related Drugs and Biologics

1.	Complement System Proteins (Complement)
2.	Proteins (Proteins, Gene)
3.	Complement Factor H (Factor H)
4.	Antigens
5.	Epitopes
6.	Complement 3d Receptors (Complement Receptor 2)
7.	von Willebrand Factor
8.	Blood Group Antigens (Blood Groups)
9.	Complement Receptors (Complement Receptor)
10.	Fc Receptors (Fc Receptor)

Related Therapies and Procedures

1.	Therapeutics
2.	Renal Dialysis (Hemodialysis)
3.	Enzyme Replacement Therapy
4.	Immunotherapy