1. Recombinant Proteins
  2. Complement System

Complement system, a major part of the innate immunity, is a cascade of soluble plasma proteins and membrane expressed receptors and regulators. Complement system operates in plasma, in tissues, on cell surface, and even within the cell. Complement system plays a key role in host homeostasis, inflammation, and in the defense against pathogens. Complement system can be activated through three main pathways: the classical pathway (CP), the lectin pathway (LP), and the alternative pathway (AP). These pathways depend on different molecules for their initiation, but they converge to generate the same set of terminal effector molecules: anaphylatoxins (C4a/C3a/C5a), the membrane attack complex (MAC), and opsonins (e.g., C3b). Complement system plays a key role in defense against pathogens and in host homeostasis.

Cat. No. Product Name / Synonyms Species Source
  • HY-P72890
    CD21 Protein, Human (HEK293, His)

    Complement receptor type 2; Cr2; EBV receptor; CD21; C3DR

    Human HEK293
    CD21 Protein, a receptor for complement C3, Epstein-Barr virus, and HNRNPU, activates B lymphocytes and aids Epstein-Barr virus entry in microbial infection. Its engagement with these ligands highlights its vital role in immune responses and interactions, regulating B-cell activation and host defense against infections. CD21 Protein, Human (HEK293, His) is the recombinant human-derived CD21 protein, expressed by HEK293 , with C-His, C-10*His labeled tag. The total length of CD21 Protein, Human (HEK293, His) is 951 a.a., with molecular weight of 110-120 kDa.
  • HY-P72946
    Complement factor H/CFH Protein, Human (372a.a, HEK293, His)

    Complement factor H; H factor 1; CFH; HF; HF1; HF2

    Human HEK293
    Complement factor H/CFH proteins regulate complement activation and act as soluble inhibitors to prevent complement amplification on the cell surface. Complement factor H/CFH Protein, Human (372a.a, HEK293, His) is the recombinant human-derived Complement factor H/CFH protein, expressed by HEK293 , with C-His labeled tag.
  • HY-P74375
    C2/Complement C2 Protein, Human (HEK293, His)

    Complement C2; C3/C5 convertase; C2

    Human HEK293
    C2/Complement C2 protein is essential in the classical pathway of the complement system. Activated by factor C1, C2 is cleaved into C2b and C2a. As a serine protease, C2a interacts with C4b, generating the C3 or C5 convertase. This crucial process activates and amplifies the complement cascade. C2/Complement C2 Protein, Human (HEK293, His) is the recombinant human-derived C2/Complement C2 protein, expressed by HEK293 , with C-His labeled tag. The total length of C2/Complement C2 Protein, Human (HEK293, His) is 732 a.a., with molecular weight of ~112 kDa.
  • HY-P7861
    Complement Factor D/Adipsin Protein, Human (HEK293, His)

    rHuComplement Factor D/Adipsin, His; Complement factor D; CFD; Adipsin; C3 convertase activator; Properdin factor D; DF; PFD

    Human HEK293
    Complement factor D, also known as Adipsin, plays a crucial role in the alternative pathway of the complement system and when complexed with factor C3b, it cleaves factor B. This cleavage activates the C3bbb complex, converting it to the C3 convertase of the alternative pathway. Complement Factor D/Adipsin Protein, Human (HEK293, His) is the recombinant human-derived Complement Factor D/Adipsin protein, expressed by HEK293 , with C-10*His labeled tag. The total length of Complement Factor D/Adipsin Protein, Human (HEK293, His) is 228 a.a., with molecular weight of ~28.0 kDa.
  • HY-P72020
    CD46 Protein, Human (HEK293, hFc)

    AHUS2; Antigen defined by monoclonal TRA 2 10; Antigen identified by monoclonal TRA 2 10; CD46; TRA2.10

    Human HEK293
    CD46 Protein serves as a cofactor for complement factor I, safeguarding cells against complement-induced harm. It aids in sperm-oocyte fusion and acts as a T-cell costimulatory factor, facilitating the formation of T-regulatory 1 cells. These cells secrete interleukin-10, suppressing immune responses and preventing autoimmunity. Pathogens can exploit CD46's immune regulation abilities to induce an immunosuppressive state in T-cells. CD46 Protein, Human (HEK293, hFc) is the recombinant human-derived CD46 protein, expressed by HEK293 , with C-hFc labeled tag.
  • HY-P75394
    CD55/DAF Protein, Human (HEK293, hFc)

    Complement Decay-Accelerating factor; CD55; CR; DAF

    Human HEK293
    The CD55/DAF protein is critical in the immune system, recognizing C4b and C3b fragments, interfering with their enzymatic conversion and preventing the formation of complement cascade amplifying convertase. This regulatory mechanism alleviates complement-induced damage by inhibiting complement activation. CD55/DAF Protein, Human (HEK293, hFc) is the recombinant human-derived CD55/DAF protein, expressed by HEK293 , with C-hFc labeled tag. The total length of CD55/DAF Protein, Human (HEK293, hFc) is 319 a.a., with molecular weight of 95-105 kDa.
  • HY-P700862
    Complement C5 Protein, Human (HEK293, His)

    Complement C5; C5; CPAMD4; ECLZB; C5a; C5b; C5D

    Human HEK293
    Complement C5 is activated by C5 convertase, inducing C5-C9 assembly to form the membrane attack complex. The transient C6 binding site on C5b is critical for the formation of the cleavage complex. Complement C5 Protein, Human (HEK293, His) is the recombinant human-derived Complement C5 protein, expressed by HEK293 , with C-His labeled tag. The total length of Complement C5 Protein, Human (HEK293, His) is 1658 a.a., with molecular weight of 110-114 kDa (α chain) & 69-73 kDa (β chain), respectively.
  • HY-P7861A
    Complement Factor D/Adipsin Protein, Human (HEK293, His, Solution)

    rHuComplement Factor D/Adipsin, His; Complement factor D; CFD; Adipsin; C3 convertase activator; Properdin factor D; DF; PFD

    Human HEK293
    Complement factor D, also known as Adipsin, plays a crucial role in the alternative pathway of the complement system and when complexed with factor C3b, it cleaves factor B. This cleavage activates the C3bbb complex, converting it to the C3 convertase of the alternative pathway. Complement Factor D/Adipsin Protein, Human (HEK293, His, Solution) is the recombinant human-derived Complement Factor D/Adipsin protein, expressed by HEK293 , with C-10*His labeled tag. The total length of Complement Factor D/Adipsin Protein, Human (HEK293, His, Solution) is 228 a.a., with molecular weight of ~28.0 kDa.
  • HY-P7862
    Complement C3/C3a Protein, Human

    rHuComplement C3/C3a; Complement Component C3a; C3a; Anaphylatoxin

    Human E. coli
    Complement C3/C3a protein plays a key role in initiating the complement system through processing by C3 convertase in both the classical and alternative pathways. Complement C3/C3a protein is involved in various immune and inflammatory responses and also has a role in regulating blood pressure. Complement C3/C3a Protein, Human is a recombinant Complement C3/C3a protein expressed in E. coli, untagged, and consists of 77 amino acids (S672-R748).
  • HY-P7864
    Complement C5/C5a Protein, Human

    rHuComplement C5/C5a; Complement C5; C5a anaphylatoxin; C5a

    Human E. coli
    Complement C5/C5a Protein, Human is a recombinant human complement C5a. C5a is a 74-amino acid glycoprotein generated on activation of the C system. Complement C5 is cleaved by proteolysis in the terminal phase of complement activation generating the pro-inflammatory C5a and membrane attack complex nucleator C5b. C5a is an inflammatory mediator generated by complement activation that positively regulates various arms of immune defense, including Toll-like receptor 4 (TLR4) signaling.
  • HY-P7863
    Complement C3/C3a Protein, Mouse

    rMuComplement C3/C3a; Complement Component C3a; Anaphylatoxin; C3a

    Mouse E. coli
    Complement C3/C3a protein activates the complement system, playing a central role in both classical and alternative pathways. C3b binds covalently to cell surface carbohydrates or immune aggregates, while C3a acts as an inflammatory mediator, inducing neutrophil chemoattraction and promoting smooth muscle contraction, increased vascular permeability, and histamine release. The shorter isoform of C3a stimulates B-cells. Complement C3/C3a Protein, Mouse is the recombinant mouse-derived Complement C3/C3a protein, expressed by E. coli , with tag free.
  • HY-P7695
    Complement C5/C5a Protein, Mouse

    rMuC5a; Complement C5; Hemolytic Complement; C5a

    Mouse E. coli
    Complement C5/C5a Protein, Mouse is a recombinant mouse complement component 5a (C5a). C5a is a potent pro-inflammatory mediator and acts as an essential part of the innate immune response.
  • HY-P7691
    CD93/C1qR1 Protein, Human (HEK293, His)

    rHuCD93, His; Complement Component C1q Receptor; Matrix-Remodeling-Associated Protein 4CD93; CD93

    Human HEK293
    CD93/C1qR1 Protein, Human (HEK293, His) is a recombinant human CD93 produced in HEK293 cells, with His tag. CD93 is a type 1 transmembrane glycoprotein.
  • HY-P70055
    CFHR1 Protein, Human (HEK293, His)

    rHuComplement Factor H-related 1/CFHR1, His; Complement Factor H-Related Protein 1; FHR-1; H Factor-Like Protein 1; H-Factor-Like 1; H36; CFHR1; CFHL; CFHL1; CFHL1P; CFHR1P; FHR1; HFL1; HFL2

    Human HEK293
    CFHR1, a key complement regulator, actively engages in the finely tuned complement system. Dimerized CFHR1 demonstrates avidity for tissue-bound complement fragments, challenging CFH. It also associates with lipoproteins, suggesting involvement in lipid metabolism. With a unique head-to-tail homodimeric structure, CFHR1 forms heterodimers with CFHR2 or CFHR5, showcasing its versatile role in complement-related processes. CFHR1 Protein, Human (HEK293, His) is the recombinant human-derived CFHR1 protein, expressed by HEK293 , with C-6*His labeled tag. The total length of CFHR1 Protein, Human (HEK293, His) is 312 a.a., with molecular weight of 38-50 kDa.
  • HY-P70102
    CFHR5 Protein, Human (HEK293, His)

    rHuComplement factor H-related protein 5/CFHR5, His; Complement factor H-related protein 5; CFHR5; CFHL5; FHR5

    Human HEK293
    CFHR5 is a first-line complement regulator that is actively involved in the complex dynamics of the regulatory system. Dimeric CFHR5 has significant affinity for tissue-bound complement fragments, thereby challenging CFH. CFHR5 Protein, Human (HEK293, His) is the recombinant human-derived CFHR5 protein, expressed by HEK293 , with C-6*His labeled tag. The total length of CFHR5 Protein, Human (HEK293, His) is 551 a.a., with molecular weight of ~61.0 kDa.
  • HY-P70281
    MBL2/COLEC1 Protein, Human (HEK293, His)

    rHuMannose-binding protein C/MBL-2, His; Mannose-Binding Protein C; MBP-C; Collectin-1; MBP1; Mannan-Binding Protein; Mannose-Binding Lectin; MBL2; COLEC1; MBL

    Human HEK293
    The MBL2/COLEC1 protein is a calcium-dependent lectin in innate immune defense that activates the lectin complement pathway by binding to mannose, fucose, and N-acetylglucosamine on microorganisms. MBL2/COLEC1 Protein, Human (HEK293, His) is the recombinant human-derived MBL2/COLEC1 protein, expressed by HEK293 , with C-6*His labeled tag. The total length of MBL2/COLEC1 Protein, Human (HEK293, His) is 228 a.a., with molecular weight of ~31.0 kDa.
  • HY-P72719
    CD59 Protein, Human (HEK293, His)

    CD59 glycoprotein; HRF-20; MAC-IP; MACIF; MIRL; CD59; MIC11; MIN1; MSK21

    Human HEK293
    The CD59 protein is a potent inhibitor of the complement membrane attack complex (MAC) and binds to assembled C8 and/or C9 complement, preventing the incorporation of multiple C9 copies that are critical for permeability pore formation. Its species-specific inhibitory effects extend to T cell activation, complexing with protein tyrosine kinases for signal transduction. CD59 Protein, Human (HEK293, His) is the recombinant human-derived CD59 protein, expressed by HEK293 , with C-6*His labeled tag. The total length of CD59 Protein, Human (HEK293, His) is 77 a.a., with molecular weight of 15-20 kDa.
  • HY-P78005
    MASP2 Protein, Human (His)

    MAP19; MASP-2; MASP1P1; sMap

    Human E. coli
    MASP2 Protein, a serum protease, critically activates the complement system by auto-catalytically cleaving and subsequently cleaving C2 and C4. This process leads to the activation of C3 and the formation of C3 convertase, essential for the complement cascade. MASP2 Protein, Human (His) is the recombinant human-derived MASP2 protein, expressed by E. coli , with C-His labeled tag.
  • HY-P78247
    Complement C3 Protein, Mouse (HEK293, His)

    Complement C3; HSE-MSF; C3; CPAMD1; AHUS5; ARMD9; ASP; C3a; C3b; HEL-S-62p

    Mouse HEK293
    Complement C3 protein activates the complement system, playing a central role in both classical and alternative pathways. C3b binds covalently to cell surface carbohydrates or immune aggregates, while C3a acts as an inflammatory mediator, inducing neutrophil chemoattraction and promoting smooth muscle contraction, increased vascular permeability, and histamine release. The shorter isoform of C3a stimulates B-cells. Complement C3 Protein, Mouse (HEK293, His) is the recombinant mouse-derived Complement C3 protein, expressed by HEK293 , with C-His labeled tag.
  • HY-P78595
    Complement C5/C5a Protein, Cynomolgus

    C5a; Complement Component 5a

    Cynomolgus E. coli
    Complement C5 is activated by C5 convertase, inducing C5-C9 assembly to form the membrane attack complex. The transient C6 binding site on C5b is critical for the formation of the cleavage complex. Complement C5/C5a Protein, Cynomolgus is the recombinant cynomolgus-derived Complement C5/C5a protein, expressed by E. coli , with tag free. The total length of Complement C5/C5a Protein, Cynomolgus is 74 a.a., with molecular weight of ~11 kDa.
Cat. No. Product Name Effect Purity