• Product name
    Human Cancer Antigen CA125 ELISA Kit
    See all Cancer Antigen CA125 kits
  • Detection method
  • Sample type
  • Assay type
    Sandwich (quantitative)
  • Sensitivity
    = 5 U/ml
  • Range
    5 U/ml - 400 U/ml
  • Assay duration
    Multiple steps standard assay
  • Species reactivity
    Reacts with: Human
  • Product overview

    ab108653 is for the quantitative determination of the Cancer Antigen CA125 concentration in human serum.

    Cancer Antigen 125 (CA125) is a surface antigen associated with epithelial ovarian cancer. In serum, CA125 is associated with a high molecular weight glycoprotein. Published studies have indicated that elevated serum CA125 levels can be found in individuals with serious endometroid, clear-cell and undifferentiated ovarian carcinoma.

    The serum CA125 concentration is greater than 35 units per ml in 60% of women with ovarian cancer and >80% of patients with disseminated ovarian cancer. The serum CA125 is elevated in 1% of normal healthy women, 3% of normal healthy women with benign ovarian diseases, and 6% of patients with non-neoplastic conditions (including but not limited to first trimester pregnancy, menstruation, endometriosis, uterine fibrosis, acute salphingitis, hepatic diseases and inflammation of peritoneum, pericardium or pleura). Serum CA125 concentration may be useful in monitoring treatment and distinguishing between good response to treatment and progressive malignant disease with poor therapeutic response. To date, CA125 is the most sensitive marker for residual epithelial ovarian cancer.

    For higher sensitivity in only 90 minutes, we recommend Human CA125 ELISA Kit (MUC16) (ab195213) from our SimpleStep ELISA® range.

  • Tested applications
    Suitable for: ELISAmore details
  • Platform


  • Storage instructions
    Store at +4°C. Please refer to protocols.
  • Components 1 x 96 tests
    20X Washing Solution 1 x 50ml
    CA125 Reference Standard 0 (1 ml, 0 U/ml) 1 x 1ml
    CA125 Reference Standard 1 (1 ml, 15 U/ml) 1 x 1ml
    CA125 Reference Standard 2 (1 ml, 50 U/ml) 1 x 1ml
    CA125 Reference Standard 3 (1 ml, 100 U/ml) 1 x 1ml
    CA125 Reference Standard 4 (1 ml, 200 U/ml) 1 x 1ml
    CA125 Reference Standard 5 (1 ml, 400 U/ml) 1 x 1ml
    Enzyme Conjugate Reagent 1 x 13ml
    Murine Monoclonal anti-CA125 coated microtiter plate 1 unit
    Stop Solution 1 x 11ml
    TMB Reagent 1 x 11ml
  • Research areas
  • Function
    Thought to provide a protective, lubricating barrier against particles and infectious agents at mucosal surfaces.
  • Tissue specificity
    Expressed in corneal and conjunctival epithelia (at protein level). Overexpressed in ovarian carcinomas and ovarian low malignant potential (LMP) tumors as compared to the expression in normal ovarian tissue and ovarian adenomas.
  • Sequence similarities
    Contains 2 ANK repeats.
    Contains 56 SEA domains.
  • Domain
    Composed of three domains, a Ser-, Thr-rich N-terminal domain, a repeated domain containing more than 60 partially conserved tandem repeats of 156 amino acids each (AAs 12061-21862) and a C-terminal transmembrane contain domain with a short cytoplasmic tail.
  • Post-translational
    Heavily O-glycosylated; expresses both type 1 and type 2 core glycans.
    Heavily N-glycosylated; expresses primarily high mannose and complex bisecting type N-linked glycans.
    May be phosphorylated. Phosphorylation of the intracellular C-terminal domain may induce proteolytic cleavage and the liberation of the extracellular domain into the extracellular space.
    May contain numerous disulfide bridges. Association of several molecules of the secreted form may occur through interchain disulfide bridges providing an extraordinarily large gel-like matrix in the extracellular space or in the lumen of secretory ducts.
  • Cellular localization
    Cell membrane. Secreted > extracellular space. May be liberated into the extracellular space following the phosphorylation of the intracellular C-terminus which induces the proteolytic cleavage and liberation of the extracellular domain.
  • Information by UniProt
  • Alternative names
    • CA 125
    • CA-125
    • CA125
    • MUC 16
    • MUC-16
    • MUC16
    • MUC16_HUMAN
    • Mucin 16
    • Mucin-16
    • Ovarian cancer related tumor marker CA125
    • Ovarian cancer-related tumor marker CA125
    • Ovarian carcinoma antigen CA125
    see all
  • Database links

Associated products


Our Abpromise guarantee covers the use of ab108653 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 Use at an assay dependent dilution.


  • Example Cancer Antigen CA125 standard curve



This product has been referenced in:
See 1 Publication for this product

Customer reviews and Q&As

1-8 of 8 Abreviews or Q&A


Attached is the dilution linearity data for this antibody. The sample can be diluted with the zero standard.

Read More


Gracias por contactarnos de nuevo.

Me confirman mis compañeros del laboratorio que este kit en principio solo se ha validado con muestras de suero. Es muy probable que sea válido para usar con muestras de plasma, pero al no haberlo testado nosotros mismos no podemos asegurarlo.

Lo que le recomendamos al cliente es que antes de usar las muestras haga un pequeño ensayo en paralelo con muestras de suero y de plasma para comprobar la idoneidad del kit con estas muestras.

Si el cliente lo desea, también podemos ofrecerle un código canjeable por el valor del kit, para participar en el sistema https://www.abcam.com/abtrial, y mandarnos los resultados de testar el kit con muestras de plasma a nuestra web.

Espero que esta información sea de utilidad para el cliente. No dudes en contactarme de nuevo si necesitas cualquier otra información.

Read More


Thank you for contacting us.

I received the following information from the supplying lab:

The two monoclonal antibodies used in the ab108653 ELISA kit are specific for the antigenic B-domain, similar to M-11.

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 call yesterday and for your patience while I have been in touch with the lab.

Unfortunately the antibodies used in this kit are not available for sale separately.

I am sorry that I can't be more help in this situation, but please let me know if you have any other questions or if there is anything else that we can do for you.

Read More


Thank you very much for your patience.
After having discussion with lab and my other colleagues regrettably I have to say we can't provide the product, separate than the kit. I apologize for any inconvenience caused.
I would suggest searching the protein in Biocompare website at www.biocompare.com. They have good search facility with lots of companies in their umbrella.
I hope this information is nevertheless helpful. Should you have any other question please do not hesitate to ask.

Read More


We are considering your request as high priority. We will get back to you with all the information soon.
Many thanks for having patience!

Read More


Thank you for your enquiry and your interest in our products.
We prove the CA125 reference standards for this kit in different concentrations 0, 15, 50, 100, 200, and 400 Unit/ml of CA125 6 x 1ml. Unfortunately, currently we are unable to sell the components of this kit separately.
However, I have just had a word with my colleague and we may be able to source this purified protein in the next couple of weeks if you are interested. Could you please confirm how much protein you wish use and purchase?
I look forward to hearing from you and hope to help you further.

Read More


Thank you for your enquiry. I can confirm that this kit is sourced externally. They have kindly provided the following information: 1. When this kit was first designed, the antigens used were not pure.  So the antigen concentrations was expressed in U/ml.  U is an arbitrary assigned number.  From then on, most (if not all) other companies manufacturing kits for ELISA detection of the cancer antigens calibrated their standards against the original kit.   The standards used in the kit are still calibrated this way. 2, I am sorry it would not be possible to convert from U to ng. I hope this information will be helpful. If you have any further questions, please do not hesitate to contact us.      

Read More


Sign up