Convertases, specifically the C3 convertases C3b.Bb and C4b.2a, are the enzymes that drive complement activation by activating C3b, a central component of the complement system. (wikipedia.org)
CD554
In various cancer cell lines, including rituximab-resistant lymphoma cells, the SBU-CD55 × CD20 antibody showed significantly higher CDC activity than either anti-CD20 IgG antibody alone or a combination of anti-CD20 IgG antibody and anti-CD55 IgG antibody. (bvsalud.org)
Furthermore, the asymmetric bispecific antibody (SBU-CD55 × CD20) exhibited significantly higher CDC activity against rituximab-resistant cancer cells compared to other bispecific antibodies with symmetric features. (bvsalud.org)
We report 2 children with distinct causes of polycythemia, 1 from systemic capillary leak syndrome (SCLS) and the other from protein-losing enteropathy (PLE) caused by CD55 deficiency. (bvsalud.org)
OBJECTIVES: This study aimed to evaluate the expression pattern of complement regulatory proteins (CRPs) CD46, CD59, and CD55 in HPV-positive (HPV+) & negative (HPV-) cervical cancer cell lines in search of a reliable differential biomarker. (bvsalud.org)
Binds3
describes the use of a phage-displayed combinatorial random peptide library to identify a 27-residue peptide that binds to C3 and inhibits complement activation. (justia.com)
Proteolytic activation of C3 yields C3b, which covalently binds to pathogenic or self surfaces providing a strong signal for clearance of the tagged particles. (justia.com)
For example, C3b.Bb is an important convertase that is part of the alternative pathway, and it is formed when factor B binds C3b and is subsequently cleaved. (wikipedia.org)
CD591
Other CCPs prevent the activity of terminal effectors of the complement system, CD59 for example blocks oligomerization of the complement peptide C9 stalling the formation of the Membrane Attack Complex (MAC). (wikipedia.org)
Peptide3
This peptide was truncated to a 13-residue cyclic segment that maintained complete activity, which is referred to in the art as compstatin (SEQ ID NO: 2J. (justia.com)
Because compstatin blocks this critical step of complement activation and because it is a small non-immunogenic peptide, compstatin has the potential to be developed into a therapeutic agent. (justia.com)
Compstatin (SEQ ID NO:2), a 13-residue peptide, circularized by disulfide bond (Cys-2-Cys-12), displays an inhibitory activity of IC 50 =12 μM. (justia.com)
Inhibitors5
Several complement inhibitors currently under development target various steps in the complement activation pathways. (justia.com)
These two latter pathogenic mechanisms are the target of novel strategies of anti-complement treatments, which can be split into terminal and proximal complement inhibitors. (frontiersin.org)
Many novel terminal complement inhibitors are now in clinical development: they all target C5 (as eculizumab), potentially paralleling the efficacy and safety profile of eculizumab. (frontiersin.org)
Indeed, we envision a new scenario of therapeutic complement inhibition, where proximal inhibitors (either anti-C3, anti-FD or anti-FB) may prove effective for the treatment of PNH, either in monotherapy or in combination with anti-C5 agents, eventually leading to drastic improvement of hematological response. (frontiersin.org)
Pathway4
This interaction results in the formation of C4b2a, which is the classic pathway C3b convertase. (medscape.com)
The alternative pathway utilizes C3 and factors B and D to form the alternative pathway convertase C3b,Bb. (medscape.com)
Small amounts of C3b are constantly being formed in the circulation, which are inactivated by factors H and I. The binding of C3b to a foreign antigen decreases its affinity for factor H and allows for the formation of increasing amounts of the alternate pathway convertase. (medscape.com)
C3b is an opsonin itself, and C3 convertase facilitates the activation of the terminal pathway and the formation of the membrane attack complex C5b-9. (medscape.com)
Cascade2
This invention relates to activation of the complement cascade in the body. (justia.com)
if C3b is bound to a bacterium, factor B will bind and the cascade will be set off as normal. (wikipedia.org)
Convertase1
Most CCPs function by preventing convertase activity. (wikipedia.org)
Tissue1
Inappropriate activation of the complement system leads to tissue injury causing or aggravating various pathological conditions, such as autoimmune diseases, burn injuries, Alzheimer's disease, stroke and heart attack, among others (reviewed by Sahu and Lambris, 2000). (justia.com)
Possess2
Many of the substances under investigation possess the disadvantage of being a large molecular weight proteins that are difficult to manufacture and must be administered by infusion. (justia.com)
RCA proteins typically possess CCP domains, also termed Sushi domains or Short Consensus Repeats (SCR). (wikipedia.org)
Activation4
Clinical presentations are similar for the three types of MPGN, but they manifest somewhat different mechanisms of complement activation and predisposition to recur in kidney transplants. (medscape.com)
Compstatin inhibits complement response by preventing the proteolytic activation of C3 (Sahu et al. (justia.com)
The complement system is tightly regulated by a network of proteins known as "regulators of complement activation (RCA)" that help distinguish target cells as "self" or "non-self. (wikipedia.org)
Most CCPs prevent activation of the complement system on the surface of host cells and protect host tissues against damage caused by autoimmunity. (wikipedia.org)
System4
The normal complement system consists of the classic and alternative pathways. (medscape.com)
Complement control protein are proteins that interact with components of the complement system. (wikipedia.org)
A subset of this family of proteins, complement control proteins (CCP), are characterized by domains of conserved repeats that direct interaction with components of the complement system. (wikipedia.org)
Efforts to develop therapeutics that target the interactions between the RCA network, CCPs, and components of the complement system have led to the development of successful drugs including Eculizumab. (wikipedia.org)
Response1
Preliminary data clearly demonstrate that proximal complement inhibition is pharmacologically feasible and apparently safe, and may drastically improve the hematological response to complement inhibition in PNH. (frontiersin.org)
Complex2
The structure of C3c in complex with the complement inhibitor, compstatin, and use of this information for rational design or identification of complement-inhibiting drugs are disclosed. (justia.com)
Complement-dependent cytotoxicity (CDC), which eliminates aberrant target cells through the assembly and complex formation of serum complement molecules, is one of the major effector functions of anticancer therapeutic antibodies. (bvsalud.org)
Family1
There are many other RCA proteins that do not fall into this family. (wikipedia.org)
Factor2
conversely, in the absence of sialic acid, factor B can bind C3b more easily. (wikipedia.org)
At the moment there are three strategies of proximal complement inhibition: anti-C3 agents, anti-factor D agents and anti-factor B agents. (frontiersin.org)
Serum2
Complement factor I (factor I) is a protein of the complement system, first isolated in 1966 in guinea pig serum, that regulates complement activation by cleaving cell-bound or fluid phase C3b and C4b. (wikipedia.org)
It binds to a variety of human serum proteins, such as albumin, complement inhibitors including Factor H (FH) and C4b-binding protein (C4BP), and the Fc portion of immunoglobulins ( 8 , 11 , 15 - 17 ). (frontiersin.org)
Domain protein1
HN - 2006(1981) BX - Cofilins MH - Actin-Related Protein 2 UI - D051377 MN - D5.750.78.730.246.500 MN - D12.776.220.525.246.500 MS - A PROFILIN binding domain protein that is part of the Arp2-3 complex. (nih.gov)
Regulate1
AN - coordinate IM with ADENOMA (IM) HN - 2006 BX - Corticotroph Adenoma BX - Pituitary Adenoma, ACTH-Secreting BX - Pituitary Corticotropin-Secreting Adenoma MH - Actin Capping Proteins UI - D051344 MN - D5.750.78.730.32 MN - D12.776.220.525.32 MS - Actin capping proteins are cytoskeletal proteins that bind to the ends of ACTIN FILAMENTS to regulate actin polymerization. (nih.gov)
Affinity1
Small amounts of C3b are constantly being formed in the circulation, which are inactivated by factors H and I. The binding of C3b to a foreign antigen decreases its affinity for factor H and allows for the formation of increasing amounts of the alternate pathway convertase. (medscape.com)
Clinical2
Dysregulated factor I activity has clinical implications. (wikipedia.org)
Clinical presentations are similar for the three types of MPGN, but they manifest somewhat different mechanisms of complement activation and predisposition to recur in renal transplants. (medscape.com)
Human3
Immune evasion strategies employed by the bacteria include binding of the complement inhibitors, C4b-binding protein (C4BP) and Factor H in a human-specific manner. (frontiersin.org)
Dimerization of Protein H is pivotal for enhanced binding to human C4BP. (frontiersin.org)
Taken together, our data show how S. pyogenes exploits human IgG to evade complement and enhance its virulence. (frontiersin.org)
Results2
Loss of function mutations in the Complement Factor I gene lead to low levels of factor I which results in increased complement activity. (wikipedia.org)
This interaction results in the formation of C4b2a, which is the classic pathway C3b convertase. (medscape.com)
Foreign1
The complement cascade comprises over 30 proteins that can mark (opsonize) targets such as pathogens, debris or foreign cells for removal by phagocytes. (frontiersin.org)
Levels1
It is expressed at higher levels than ARP2 PROTEIN and does not contain a PROFILIN binding domain. (nih.gov)