• Product name

  • Description

    Rabbit polyclonal to C4a
  • Host species

  • Tested applications

    Suitable for: WB, ICC/IFmore details
  • Species reactivity

    Reacts with: Human
  • Immunogen

    Synthetic peptide corresponding to Human C4a aa 700-800 conjugated to keyhole limpet haemocyanin.
    (Peptide available as ab86260)

  • Positive control

    • This antibody gave a positive signal in HepG2 Whole Cell Lysate and plasma total protein lysate.


  • Form

  • Storage instructions

    Shipped at 4°C. Store at +4°C short term (1-2 weeks). Upon delivery aliquot. Store at -20°C or -80°C. Avoid freeze / thaw cycle.
  • Storage buffer

    Preservative: 0.02% Sodium Azide
    Constituents: 1% BSA, PBS, pH 7.4
  • Concentration information loading...
  • Purity

    Immunogen affinity purified
  • Clonality

  • Isotype

  • Research areas


Our Abpromise guarantee covers the use of ab66790 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
WB Use a concentration of 1 µg/ml. Detects a band of approximately 193 kDa (predicted molecular weight: 193 kDa).
ICC/IF Use at an assay dependent concentration. PubMed: 23236492


  • Function

    C4 plays a central role in the activation of the classical pathway of the complement system. It is processed by activated C1 which removes from the alpha chain the C4a anaphylatoxin. The remaining alpha chain fragment C4b is the major activation product and is an essential subunit of the C3 convertase (C4b2a) and the C5 convertase (C3bC4b2a) enzymes of the classical complement pathway.
    Derived from proteolytic degradation of complement C4, C4a anaphylatoxin is a mediator of local inflammatory process. It induces the contraction of smooth muscle, increases vascular permeability and causes histamine release from mast cells and basophilic leukocytes.
  • Involvement in disease

    Defects in C4A are the cause of complement component 4A deficiency (C4AD) [MIM:120810]. A rare defect of the complement classical pathway associated with the development of autoimmune disorders, mainly systemic lupus with or without associated glomerulonephritis.
  • Sequence similarities

    Contains 1 anaphylatoxin-like domain.
    Contains 1 NTR domain.
  • Post-translational

    Prior to secretion, the single-chain precursor is enzymatically cleaved to yield the non-identical chains (alpha, beta and gamma). During activation, the alpha chain is cleaved by C1 into C4a and C4b, and C4b stays linked to the beta and gamma chains. Further degradation of C4b by C1 into the inactive fragments C4c and C4d blocks the generation of C3 convertase.
    N- and O-glycosylated. O-glycosylated with a core 1 or possibly core 8 glycan.
  • Cellular localization

  • Information by UniProt
  • Database links

  • Alternative names

    • Acidic complement C4 antibody
    • C3 and PZP like alpha 2 macroglobulin domain containing protein 2 antibody
    • C3 and PZP-like alpha-2-macroglobulin domain-containing protein 2 antibody
    • C4a anaphylatoxin antibody
    • C4A antibody
    • C4AD antibody
    • CO4A_HUMAN antibody
    • Complement C4 A antibody
    • Complement C4 gamma chain antibody
    • Complement component 4A antibody
    • Complement component 4A preproprotein antibody
    • CPAMD2 antibody
    • RG antibody
    • Rodgers form of C4 antibody
    see all


  • Anti-C4a antibody (ab66790) at 1 µg/ml + HepG2 (Human) Whole Cell Lysate (ab52257) at 10 µg

    Goat polyclonal to Rabbit IgG - H&L - Pre-Adsorbed (HRP) (ab65484) at 1/3000 dilution

    Developed using the ECL technique.

    Performed under reducing conditions.

    Predicted band size: 193 kDa
    Observed band size: 193 kDa

  • Anti-C4a antibody (ab66790) at 1 µg/ml + Human Plasma Total Protein Lysate at 10 µg

    Goat polyclonal to Rabbit IgG - H&L - Pre-Adsorbed (HRP) at 1/3000 dilution

    Developed using the ECL technique.

    Performed under reducing conditions.

    Predicted band size: 193 kDa
    Observed band size: 95 kDa
    why is the actual band size different from the predicted?
    Additional bands at: 35 kDa, 41 kDa. We are unsure as to the identity of these extra bands.

    Complement C4-A is proteolytically cleaved to yield three non-identical chains and circulates in blood as a disulphide-linked trimer of an alpha, beta and gamma chain (95, 75 and 33 kDa respectively). We propose that the 95 kDa band corresponds to the alpha chain of Complement C4-A.


This product has been referenced in:

  • Cheng CW  et al. Sex hormone-binding globulin (SHBG) is a potential early diagnostic biomarker for gastric cancer. Cancer Med 7:64-74 (2018). WB . Read more (PubMed: 29148252) »
  • Treutlein G  et al. Novel potential interacting partners of fibronectin in spontaneous animal model of interstitial cystitis. PLoS One 7:e51391 (2012). WB, ICC/IF ; Cat . Read more (PubMed: 23236492) »
See all 2 Publications for this product

Customer reviews and Q&As

1-2 of 2 Abreviews or Q&A

Human Cell lysate - other (Human serum)
Total protein in input
500 µg
Immuno-precipitation step
Other - Protein A and G Dynabeads and Protein A Agarose
Human serum

Dr. Shea Hamilton

Verified customer

Submitted Sep 30 2016

Western blot
Human Cell lysate - whole cell (brain homogenate)
Loading amount
75 µg
brain homogenate
Gel Running Conditions
Non-reduced Denaturing (12)
Blocking step
BSA as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: rt°C

Abcam user community

Verified customer

Submitted Aug 21 2012

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