Complement component 5 (C5) is a vital protein in the complement system, part of the body's immune defense mechanism. Its structural unit is a single polypeptide chain made up of beta and alpha subunits joined by a disulfide bond. When activated, C5 undergoes proteolytic cleavage into C5a and C5b fragments. C5a is a powerful chemoattractant and anaphylatoxin, that recruits immune cells and causes inflammation. C5b triggers the formation of the membrane attack complex (MAC), leading to cell lysis in pathogens. Overall, C5 plays a crucial role in innate immunity and inflammatory responses.
Its Gene ID: 727, UniProtKB ID: P01031, and OMIM ID: 120900.
Fig.1 C5 convertase activates C5 to produce C5a and C5b.1,3
Complement activation pathways can trigger C5 activation through distinct mechanisms. In the classical pathway, C5 is activated after the C1 complex binds to antigen-antibody complexes. The lectin pathway involves mannose-binding lectin (MBL) or ficolins recognizing pathogen-associated molecular patterns (PAMPs), leading to C5 activation. Additionally, the alternative pathway initiates C5 activation through spontaneous hydrolysis of C3, facilitated by factors B, D, and properdin. Regardless of the pathway, C5 activation proceeds through proteolytic cleavage into C5a and C5b, eliciting potent immune responses crucial for host defense against infections and maintaining immune homeostasis.
The C5 dysfunction may cause a range of immune-related diseases, mainly including paroxysmal nocturnal hemoglobinuria (PNH), atypical hemolytic uremic syndrome (aHUS), and age-related macular degeneration (AMD). In PNH, mutations in proteins regulating the complement system lead to uncontrolled complement activation, resulting in hemolysis and thrombosis. aHUS is characterized by dysregulated complement activation, causing microvascular thrombosis and organ damage, particularly in the kidneys. AMD, a leading cause of vision loss in the elderly, involves dysregulated complement activation in the retina, leading to inflammation and damage to retinal cells. In addition, abnormal activation of C5a may be related to the occurrence and development of various diseases such as vasculitis, lupus nephritis, and cancer.
Therapeutic antibodies against C5 have changed the treatment of complement-mediated disorders. A pioneering C5 monoclonal antibody can bind to C5 with high affinity, inhibiting its cleavage into C5a and C5b, hence preventing the formation of the MAC and effectively halting complement-mediated cell lysis. It has been approved by the FDA to treat PNH and aHUS patients, and it is now being clinically evaluated for application for a variety of additional diseases. Recent years have witnessed the development of new, optimized antibodies. A humanized monoclonal antibody aimed to bind to and block the activation of C5 is a long-acting C5 inhibitor with increased dosage. It is approved for the treatment of PNH and aHUS, as well as the suppression of complement-mediated thrombotic microangiopathy (TMA). Furthermore, research continues to explore novel antibody-based strategies targeting C5 for various complement-related disorders, highlighting the therapeutic potential of inhibiting C5 in managing diverse inflammatory and autoimmune conditions.
Fig.2 Monoclonal antibody against C5 mechanism of action.2,3
Creative Biolabs offers almost seventy anti-C5 antibody products that are produced recombinantly to be used in twelve applications. Customization of C5-based blocking or neutralizing antibodies is also available for you here.
Recombinant Anti-C5 Antibody (V3S-0522-YC501) (CAT#: V3S-0522-YC501)
Target: C5
Host Species: Mouse
Target Species: Mouse,
Application: ELISA,DB,FC,FuncS,IA,IF,IP,IHC,
Anti-C5 (aa 20-124) Neutralizing Antibody (V3S-0522-YC931) (CAT#: V3S-0522-YC931)
Target: C5
Host Species: Human
Target Species: Human, Monkey,
Application: DB,ELISA,WB,FC,Neut,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1158) (CAT#: V3S-0622-YC1158)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1159) (CAT#: V3S-0622-YC1159)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1160) (CAT#: V3S-0622-YC1160)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1161) (CAT#: V3S-0622-YC1161)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1162) (CAT#: V3S-0622-YC1162)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1163) (CAT#: V3S-0622-YC1163)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1164) (CAT#: V3S-0622-YC1164)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1165) (CAT#: V3S-0622-YC1165)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1166) (CAT#: V3S-0622-YC1166)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1167) (CAT#: V3S-0622-YC1167)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1168) (CAT#: V3S-0622-YC1168)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1169) (CAT#: V3S-0622-YC1169)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1170) (CAT#: V3S-0622-YC1170)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1171) (CAT#: V3S-0622-YC1171)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1172) (CAT#: V3S-0622-YC1172)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1173) (CAT#: V3S-0622-YC1173)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1174) (CAT#: V3S-0622-YC1174)
Target: C5
Host Species: Human
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1175) (CAT#: V3S-0622-YC1175)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 Neutralizing Antibody (V3S-0622-YC1176) (CAT#: V3S-0622-YC1176)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: FuncS,
Anti-C5 (aa 727-744) Neutralizing Antibody (V3S-0522-YC500) (CAT#: V3S-0522-YC500)
Target: C5
Host Species: Human
Target Species: Human,
Application: ELISA,WB,Inhib,FuncS,
Recombinant Anti-C5 Antibody (V3S-0522-YC1462) (CAT#: V3S-0522-YC1462)
Target: C5
Host Species: Human
Target Species: Human,
Application: ELISA,IHC,FC,IP,IF,FuncS,
Anti-C5 Neutralizing Antibody (V3S-0522-YC3034) (CAT#: V3S-0522-YC3034)
Target: C5
Host Species: Human
Target Species: Human, Cynomolgus,
Application: Inhib,FuncS,
Anti-C5 Neutralizing Antibody (V3S-0522-YC6463) (CAT#: V3S-0522-YC6463)
Target: C5
Host Species: Mouse
Target Species: Mouse,
Application: Block,ELISA,
Anti-C5 Neutralizing Antibody (V3S-0522-YC6465) (CAT#: V3S-0522-YC6465)
Target: C5
Host Species: Mouse
Target Species: Mouse,
Application: Block,ELISA,
Anti-C5 Neutralizing Antibody (V3S-0522-YC7276) (CAT#: V3S-0522-YC7276)
Target: C5
Host Species: Human
Target Species: Human,
Application: Neut,FuncS,
Anti-C5 Neutralizing Antibody (V3S-0822-YC446) (CAT#: V3S-0822-YC446)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,Neut,WB,
Recombinant Anti-C5 (aa 65-73) Antibody (V3S-0822-YC448) (CAT#: V3S-0822-YC448)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IHC,FuncS,
Anti-C5 Neutralizing Antibody (V3S-0822-YC449) (CAT#: V3S-0822-YC449)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,IP,Neut,WB,
Recombinant Anti-C5 Antibody (V3S-1022-YC851) (CAT#: V3S-1022-YC851)
Target: C5
Host Species: Human
Target Species: Human, Cynomolgus,
Application: ELISA,
Recombinant Anti-C5 Antibody (V3S-1022-YC852) (CAT#: V3S-1022-YC852)
Target: C5
Host Species: Human
Target Species: Human, Cynomolgus,
Application: ELISA,
Recombinant Anti-C5 Antibody (V3S-1022-YC853) (CAT#: V3S-1022-YC853)
Target: C5
Host Species: Human
Target Species: Human, Cynomolgus,
Application: ELISA,
Recombinant Anti-C5 Antibody (V3S-1022-YC854) (CAT#: V3S-1022-YC854)
Target: C5
Host Species: Human
Target Species: Human, Cynomolgus,
Application: ELISA,
Anti-C5 Neutralizing Antibody (V3S-1022-YC1253) (CAT#: V3S-1022-YC1253)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,Neut,
Anti-C5 Neutralizing Antibody (V3S-1022-YC3284) (CAT#: V3S-1022-YC3284)
Target: C5
Host Species: Human
Target Species: Human,
Application: ELISA,Block,
Recombinant Rabbit Anti-C5 Antibody (V3S-1022-YC3286) (CAT#: V3S-1022-YC3286)
Target: C5
Host Species: Rabbit
Target Species: Human, Cynomolgus,
Application: WB,ELISA,FC,
Recombinant Anti-C5 Antibody (V3S-1022-YC3287) (CAT#: V3S-1022-YC3287)
Target: C5
Host Species: Human
Target Species: Human, Cynomolgus,
Application: WB,ELISA,FC,
Recombinant Anti-C5 Antibody (V3S-1022-YC3288) (CAT#: V3S-1022-YC3288)
Target: C5
Host Species: Human
Target Species: Human, Cynomolgus,
Application: WB,ELISA,FC,
Recombinant Anti-C5 Antibody (V3S-1222-YC526) (CAT#: V3S-1222-YC526)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC527) (CAT#: V3S-1222-YC527)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC528) (CAT#: V3S-1222-YC528)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC529) (CAT#: V3S-1222-YC529)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC530) (CAT#: V3S-1222-YC530)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC531) (CAT#: V3S-1222-YC531)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC532) (CAT#: V3S-1222-YC532)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC533) (CAT#: V3S-1222-YC533)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Recombinant Anti-C5 Antibody (V3S-1222-YC534) (CAT#: V3S-1222-YC534)
Target: C5
Host Species: Mouse
Target Species: Human,
Application: ELISA,WB,IP,
Anti-C5 Neutralizing Antibody (V3S-1222-YC1372) (CAT#: V3S-1222-YC1372)
Target: C5
Host Species: Human
Target Species: Human,
Application: ELISA,Block,
Anti-C5 Neutralizing Antibody (V3S-1222-YC1373) (CAT#: V3S-1222-YC1373)
Target: C5
Host Species: Human
Target Species: Human,
Application: ELISA,Block,
