• Product name
    Anti-C1q antibody (HRP)
    See all C1q primary antibodies
  • Description
    Sheep polyclonal to C1q (HRP)
  • Host species
  • Conjugation
  • Tested applications
    Suitable for: ELISAmore details
  • Species reactivity
    Reacts with: Human
  • Immunogen

    Human C1q



Our Abpromise guarantee covers the use of ab46191 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
ELISA 1/100 - 1/400.


  • Function
    C1q associates with the proenzymes C1r and C1s to yield C1, the first component of the serum complement system. The collagen-like regions of C1q interact with the Ca(2+)-dependent C1r(2)C1s(2) proenzyme complex, and efficient activation of C1 takes place on interaction of the globular heads of C1q with the Fc regions of IgG or IgM antibody present in immune complexes.
  • Involvement in disease
    Defects in C1QA are a cause of complement component C1q deficiency (C1QD) [MIM:613652]. A rare defect resulting in C1 deficiency and impaired activation of the complement classical pathway. C1 deficiency generally leads to severe immune complex disease with features of systemic lupus erythematosus and glomerulonephritis.
  • Sequence similarities
    Contains 1 C1q domain.
    Contains 1 collagen-like domain.
  • Post-translational
    O-linked glycans consist of Glc-Gal disaccharides bound to the oxygen atom of post-translationally added hydroxyl groups.
  • Cellular localization
  • Information by UniProt
  • Database links
  • Alternative names
    • C1qa antibody
    • C1QA_HUMAN antibody
    • C1QB antibody
    • C1QC antibody
    • Complement C1q subcomponent subunit A antibody
    • Complement C1q subcomponent subunit B antibody
    • Complement C1q subcomponent subunit C antibody
    • Complement component 1 q subcomponent alpha polypeptide antibody
    • Complement component C1q A chain antibody
    • Complement component C1q B chain antibody
    • Complement component C1q C chain antibody
    see all


This product has been referenced in:
  • Klaus T & Bereta J CH2 Domain of Mouse IgG3 Governs Antibody Oligomerization, Increases Functional Affinity to Multivalent Antigens and Enhances Hemagglutination. Front Immunol 9:1096 (2018). Read more (PubMed: 29875771) »
  • Zhou W  et al. Characterization of antibody-C1q interactions by Biolayer Interferometry. Anal Biochem 549:143-148 (2018). Read more (PubMed: 29577875) »
See all 7 Publications for this product

Customer reviews and Q&As

1-7 of 7 Abreviews or Q&A


Thank you for contacting Abcam regarding ab46191.

I have looked into the various lots you have used and there have been no changes in the formulations, concentrations, or QC results. Because this is a polyclonal antibody, some lot-to-lot variation is expected and you may need to optimize the dilutions you are working with. I also do have another lot available and can send this if further troubleshooting does not improve your results.

I hope this information is helpful. Please do not hesitate to contact me if you have any additional questions or concerns.

Read More


Thank you for contacting us.

Please find attached the CoC certificate with this email.

I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

Use our products? Submit an Abreview. Earn rewards!

Read More


We don't do CoAs, and we state this in our FAQs: "Some of our collaborators are not certified ISO9001 and so we are not able to provide a certificate of analysis for these particular products."

However, we offer the following "As the identity of our collaborators is confidential, we provide a certificate of compliance for all of our products available in our catalogue. This document certifies that our products meet the required specifications for a particular lot/batch of product."

Is a CoC acceptable for your customer? If so, please send this request to our CS/Order team, as they usually deal with this kind of inquiry.

Read More


Thank you very much for your email.

I am sorry we don't' have explanation why the antibody gave good results when stored at -80C than 4C. Generally the antibodies are viable for months at 4C and storingthem at 4C, for couple of weeks, should not have affected the sensitivity so you may consider optimizing the protocol.

This product is covered under Abpromise Guarantee which states we will offer a replacement product if the product do not work in applications and species as stated on the datasheet. This guarantee is only valid if the product is stored as recommended.

We unfortunately will not be able to offer you the extra requested vials for stability testing, we have already done that and the datasheet was updated with the best suitable results.

I can provide further help with the protocol troubleshooting. Could you please send the protocol used? If in case there is nothing wrong with the protocol then I will be happy to offer a free of charge vial from different lot.

I will look forward to hearing from you soon. Should you have any other question please do not hesitate to contact me.

Read More


Thank you for contacting us. I am sorry to hear that you are experiencing problems with this antibody.

We changed the storage conditions of this product to ‘4 deg C do not freeze’ back in 201. This was because the buffer now included a HRP-stabiliser which is incompatible with storage at lower temperatures.

The recommended storage instructions for this antibody at the moment is store at 4C do not freeze.

Could you please send me the protocol followed and results for further investigation of lot?

I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

Read More


Thank you for your enquiry.

I can confirm that this antibodyshouldnot to be frozen but stored at +4C.

We do not have set expiration dates for our products. Most antibodies are stable and can last for anywhere from a few months to several years if stored properly, so we strongly recommend that you follow the storage instructions on the datasheet for the antibody you purchased.

We can only guarantee our products to work for at least six month from the date of purchase when stored correctly.

Freezing (and thawing)this antibody might separate the HRP molecule from the antibody andwhich will lead to aweakened strength of signalsince un-conjugated antibody is competing withconjugated antibody. This leads to less conjugated antibody binding to the target and therefore a weaker signal.

I suggest to run an test experiment to see if enough signal can still be obtained and to avoid freeze/thaw cycles at all cost.

Should there be precipitate after thawing, I recommend to spin the vial down and only use the supernatant for experiments

I hope this information helps. Please do not hesitate to contact us if you need anything further.

Read More


Thank you for contacting us. I received the following information from the supplying lab: The detailed information regarding the specifics of the immunogen (e.g. is the immunogen composed of all 3 C1q subunits A, B and C or just one of them?) are proprietary and we are not able to disclose this information. We can tell, however, that the immunogen is purified human C1 complement. It has been shown to have minimal cross reactivity with related serum proteins. We do know that this antibody reacts with beta-1-C and beta-1-A native antigen in fresh plasma. I am sorry to not have the exact information that you were looking for. Please do not hesitate to contact us if you need any more advice or information.

Read More


Sign up