Recombinant Anti-Tat-SF1 antibody [EPR9105(B)] (ab134921)


  • Product name

    Anti-Tat-SF1 antibody [EPR9105(B)]
    See all Tat-SF1 primary antibodies
  • Description

    Rabbit monoclonal [EPR9105(B)] to Tat-SF1
  • Host species

  • Tested applications

    Suitable for: WB, IHC-P, ICC/IF, IPmore details
    Unsuitable for: Flow Cyt
  • Species reactivity

    Reacts with: Rat, Human
  • Immunogen

    Synthetic peptide within Human Tat-SF1 aa 350-450. The exact sequence is proprietary.

  • Positive control

    • HeLa and Jurkat cell lysates. Human colon tissue. HepG2 cells.
  • General notes

    Mouse: We have preliminary internal testing data to indicate this antibody may not react with this species. Please contact us for more information.


    Previously labelled as HIV TAT specific factor 1. 

    Our RabMAb® technology is a patented hybridoma-based technology for making rabbit monoclonal antibodies. For details on our patents, please refer to RabMab® patents.

    This product is a recombinant rabbit monoclonal antibody.



Our Abpromise guarantee covers the use of ab134921 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 1/1000 - 1/10000. Predicted molecular weight: 86 kDa.
IHC-P 1/100 - 1/250. Perform heat mediated antigen retrieval with citrate buffer pH 6 before commencing with IHC staining protocol.
ICC/IF 1/250 - 1/500.
IP 1/10 - 1/100.
  • Application notes
    Is unsuitable for Flow Cyt.
  • Target

    • Relevance

      HIV TAT specific factor(a.k.a. HTATSF1, Tat-SF1 or HTSF1) is an 86 kDa general transcription factor that plays a role in the process of transcription elongation. However, in HIV-infected cells, this factor is up-regulated by HIV Nef and gp120 and acts as a co-factor for the Tat-enhanced transcription of the HIV virus.
    • Cellular localization

    • Database links

    • Alternative names

      • Cofactor required for Tat activation of HIV 1 transcription antibody
      • dJ196E23.2 antibody
      • HIV Tat specific factor 1 antibody
      • HTATSF1 antibody
      • HTSF-1 antibody
      • HTSF1 antibody
      • TAT SF1 antibody
      • Tat-SF1 antibody
      see all


    • All lanes : Anti-Tat-SF1 antibody [EPR9105(B)] (ab134921) at 1/1000 dilution

      Lane 1 : HeLa cell lysate
      Lane 2 : Jurkat cell lysate

      Lysates/proteins at 10 µg per lane.

      All lanes : Goat-anti-rabbit HRP at 1/2000 dilution

      Developed using the ECL technique.

      Predicted band size: 86 kDa

    • Immunohistochemical analysis of paraffin-embedded Human colon tissue labelling Tat-SF1 with ab134921 at 1/100 dilution.

    • Immunohistochemical analysis of paraffin-embedded Human kidney tissue labelling Tat-SF1 with ab134921 at 1/100 dilution.

    • Immunofluorescence analysis of HepG2 cells staining Tat-SF1 with ab134921 at 1/250 dilution.

    • Immunohistochemical analysis using ab134921 showing positive staining in Normal testis tissue.

    • Immunohistochemical analysis using ab134921 showing positive staining in Breast carcinoma tissue.

    • Equilibrium disassociation constant (KD)
      Learn more about KD

      Click here to learn more about KD


    ab134921 has not yet been referenced specifically in any publications.

    Customer reviews and Q&As


    Thank you for contacting us yesterday in regards to the anti-HIV TAT specific factor 1 antibody [EPR9105(B)], ab134921.

    As discussed over the phone, we have as yet not tested this antibody in ChIP and we have not received any reports from our customers to say they have either. This does not mean that it would not be suitable for this application, simply that we have not tried it and would not be able to guarantee its performance.

    I have contacted the lab to ascertain what the results in IP have been with this antibody. I have attached the image of the blot to this email (ant this will also be added to the datasheet of ab134921 so other customers can evaluate its performance). The antibody was tested with Jurkat cell lysate. As you can see, there is the expected band at ˜120 kDa (which was observed in the Western blot as well)but there is also a strong, non-specific band at ˜50 kDa.

    This may mean that the ChIP experiment would not be clean, but I think it might be worth trying. We do not do a lot of optimisation of the IP experiment and it may be with some optimisation the binding to the 50 kDa band can be improved on.

    If you would like to try ab134921 in ChIP I would be able to offer you a testing discount.This offer means that if you purchase ab134921 as normal, test the antibody in ChIP and let us know of the results through an Abreview (no matter whether positive or negative) you would be eligible for a free primary antibody of your choice from our catalogue (or the equivalent price ofab134921 off any product). More information on this offer can be found here:

    Please note that the antibody to be tested must be purchased, tested, the Abreview submitted and the free product claimed within a 4 month period.

    If you would be interested in participating in this scheme please do let me know as a discount code needs to be issued prior to the purchase of ab134921.

    I hope this information has been of help. If you require any further information please do not hesitate to contact us again.

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