• Product name
    Anti-CD40 antibody [B-B20] (FITC)
    See all CD40 primary antibodies
  • Description
    Mouse monoclonal [B-B20] to CD40 (FITC)
  • Host species
  • Conjugation
    FITC. Ex: 493nm, Em: 528nm
  • Specificity
    This antibody recognises the Bp50 antigen
  • Tested applications
    Suitable for: Flow Cytmore details
  • Species reactivity
    Reacts with: Human, Common marmoset
  • Immunogen

    Raji cell line (Human)

  • Positive control
    • Human lymphocytes
  • General notes

    Abcam is committed to meeting high standards of ethical manufacturing and has decided to discontinue this product by June 2019 as it has been generated by the ascites method. We are sorry for any inconvenience this may cause. 




Our Abpromise guarantee covers the use of ab27281 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
Flow Cyt Use 10µl for 106 cells.

or 100 µl of whole blood.




ab91356 - Mouse monoclonal IgG1, is suitable for use as an isotype control with this antibody.



  • Function
    Receptor for TNFSF5/CD40LG.
  • Tissue specificity
    B-cells and in primary carcinomas.
  • Involvement in disease
    Defects in CD40 are the cause of hyper-IgM immunodeficiency syndrome type 3 (HIGM3) [MIM:606843]; also known as hyper-IgM syndrome 3. HIGM3 is an autosomal recessive disorder which includes an inability of B cells to undergo isotype switching, one of the final differentiation steps in the humoral immune system, an inability to mount an antibody-specific immune response, and a lack of germinal center formation.
  • Sequence similarities
    Contains 4 TNFR-Cys repeats.
  • Cellular localization
    Secreted and Cell membrane.
  • Information by UniProt
  • Database links
  • Alternative names
    • AI326936 antibody
    • B cell associated molecule CD40 antibody
    • B cell surface antigen CD40 antibody
    • B cell-associated molecule antibody
    • B-cell surface antigen CD40 antibody
    • Bp50 antibody
    • CD 40 antibody
    • CD40 antibody
    • CD40 antigen (TNF receptor superfamily member 5) antibody
    • CD40 antigen antibody
    • CD40 molecule antibody
    • CD40 molecule, TNF receptor superfamily member 5 antibody
    • CD40 protein antibody
    • CD40 type II isoform antibody
    • CD40L receptor antibody
    • CDw40 antibody
    • GP39 antibody
    • HIGM1 antibody
    • IGM antibody
    • IMD3 antibody
    • MGC9013 antibody
    • Nerve growth factor receptor related B lymphocyte activation molecule antibody
    • OTTHUMP00000031699 antibody
    • OTTHUMP00000031700 antibody
    • p50 antibody
    • T-BAM antibody
    • TBAM antibody
    • TNF receptor superfamily member 5 antibody
    • TNFRSF5 antibody
    • TNR5_HUMAN antibody
    • TRAP antibody
    • Tumor necrosis factor receptor superfamily , member 5 antibody
    • Tumor necrosis factor receptor superfamily member 5 antibody
    • Tumor necrosis factor receptor superfamily member 5 precursor antibody
    • Tumor necrosis factor receptor superfamily, member 5, isoform CRA_a antibody
    see all


  • A typical staining pattern with the B-B20 monoclonal antibody of lymphocytes


This product has been referenced in:
  • Toyoshima K  et al. Analysis of circulating tumor cells derived from advanced gastric cancer. Int J Cancer 137:991-8 (2015). Flow Cyt ; Human . Read more (PubMed: 25622566) »
  • Tudor CS  et al. Macrophages and dendritic cells as actors in the immune reaction of classical Hodgkin lymphoma. PLoS One 9:e114345 (2014). Flow Cyt . Read more (PubMed: 25470820) »
See all 4 Publications for this product

Customer reviews and Q&As

1-3 of 3 Abreviews or Q&A


Thank you for contacting us.

We will send you the concentration details soon.

Many thanks for having patience!

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Ok, thanks for letting me know. The Anti-CD40 PE antibody ab27282 should be stored at +4°C (not suitable for freezing) and we would expect this to remain active up to a year after purchase. The Anti-CD40 FITC antibody ab27281 can be aliquotted and stored long term at -20°C. This should then remain active for up to 5 years. I hope the newer batch of ab27282 is working well. If you have any problems or questions in the future please do not hesitate to contact us again.

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Thank you for contacting us. I'm sorry that you have been experiencing problems with Anti-CD40 antibody [B-B20] (Phycoerythrin) (ab27282). I have checked our records and we haven't had any reports of the antibody not working but as you have been able to use ab27281 against the same target with no problem clearly the antibody is not performing as expected. If you have been following the storage instructions provided with the product then this again should not have contributed to the problem encountered. The only thing that may be an issue but I'm sure you are aware of is that the emission for the dyes are 476 and 519 nm for ab27282 and ab27281 respectively and the filters used for flow cytometry need to be set up accordingly. It may be that the lot you have received is faulty and I can offer you a free of charge replacement for this antibody. Alternatively I can organise a refund as this product is covered by the Abpromise guarantee. In order to do this could you please give me the order number, address of your institute and/or the date on which the antibody was purchased. More details about the Abpromise can be found here: https://www.abcam.com/index.html?pageconfig=resource&rid=10372

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