• Product name

    Anti-CD33 antibody [EPR4423]
    See all CD33 primary antibodies
  • Description

    Rabbit monoclonal [EPR4423] to CD33
  • Host species

  • Tested applications

    Suitable for: WB, IPmore details
    Unsuitable for: IHC-P
  • Species reactivity

    Reacts with: Human
  • Immunogen

    Synthetic peptide within Human CD33 aa 1-100. The exact sequence is proprietary.

  • Positive control

    • WB: THP1 cell lysate, U937 cell lysate, HL 60 cell lysate, HepG2 whole cell lysate (ab7900), HeLa whole cell lysate (ab150035)
  • General notes

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


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

    We are constantly working hard to ensure we provide our customers with best in class antibodies. As a result of this work we are pleased to now offer this antibody in purified format. We are in the process of updating our datasheets. The purified format is designated 'PUR' on our product labels. If you have any questions regarding this update, please contact our Scientific Support team.

    This product is a recombinant rabbit monoclonal antibody.



Our Abpromise guarantee covers the use of ab134115 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. Detects a band of approximately 67-75 kDa (predicted molecular weight: 40 kDa).
IP 1/10 - 1/100.
  • Application notes
    Is unsuitable for IHC-P.
  • Target

    • Function

      Putative adhesion molecule of myelomonocytic-derived cells that mediates sialic-acid dependent binding to cells. Preferentially binds to alpha-2,6-linked sialic acid. The sialic acid recognition site may be masked by cis interactions with sialic acids on the same cell surface. In the immune response, may act as an inhibitory receptor upon ligand induced tyrosine phosphorylation by recruiting cytoplasmic phosphatase(s) via their SH2 domain(s) that block signal transduction through dephosphorylation of signaling molecules. Induces apoptosis in acute myeloid leukemia (in vitro).
    • Tissue specificity

      Monocytic/myeloid lineage cells.
    • Sequence similarities

      Belongs to the immunoglobulin superfamily. SIGLEC (sialic acid binding Ig-like lectin) family.
      Contains 1 Ig-like C2-type (immunoglobulin-like) domain.
      Contains 1 Ig-like V-type (immunoglobulin-like) domain.
    • Domain

      Contains 2 copies of a cytoplasmic motif that is referred to as the immunoreceptor tyrosine-based inhibitor motif (ITIM). This motif is involved in modulation of cellular responses. The phosphorylated ITIM motif can bind the SH2 domain of several SH2-containing phosphatases.
    • Post-translational

      Phosphorylation of Tyr-340 is involved in binding to PTPN6 and PTPN11. Phosphorylation of Tyr-358 is involved in binding to PTPN6.
    • Cellular localization

      Cell membrane.
    • Information by UniProt
    • Database links

    • Alternative names

      • CD 33 antibody
      • CD33 antibody
      • CD33 antigen (gp67) antibody
      • CD33 antigen antibody
      • CD33 molecule antibody
      • CD33_HUMAN antibody
      • FLJ00391 antibody
      • gp67 antibody
      • My9 antibody
      • Myeloid cell surface antigen CD33 antibody
      • Myeloid cell surface antigen CD33 precursor antibody
      • Myeloid differentiation antigen CD33 antibody
      • p67 antibody
      • Sialic acid binding Ig like lectin 3 antibody
      • Sialic acid binding immunoglobulin like lectin 3 antibody
      • Sialic acid-binding Ig-like lectin 3 antibody
      • SIGLEC 3 antibody
      • Siglec-3 antibody
      • SIGLEC3 antibody
      see all


    • All lanes : Anti-CD33 antibody [EPR4423] (ab134115) at 1/5000 dilution (purified)

      Lane 1 : THP-1 cell lysate
      Lane 2 : U937 cell lysate

      Lysates/proteins at 10 µg per lane.

      All lanes : HRP goat anti-rabbit IgG (H+L) at 1/20000 dilution

      Predicted band size: 40 kDa
      Observed band size: 67,75 kDa
      why is the actual band size different from the predicted?

      Blocking buffer: 5% NFDM/TBST
      Dilution buffer: 5% NFDM/TBST

    • Equilibrium disassociation constant (KD)
      Learn more about KD

      Click here to learn more about KD
    • ab134115 (purified) at 1/60 immunoprecipitating CD33 in 10 μg THP-1 (Lanes 1 and 2, observed at 67-75 kDa). Lane 3 - PBS. For western blotting, VeriBlot for IP Detection Reagent (HRP) (ab131366), was used for detection at 1/10,000 dilution. Blocking buffer and concentration: 5% NFDM/TBST Dilution buffer and concentration: 5% NFDM/TBST

    • All lanes : Anti-CD33 antibody [EPR4423] (ab134115) at 1/1000 dilution (unpurified)

      Lane 1 : THP1 cell lysate
      Lane 2 : U937 cell lysate
      Lane 3 : HL60 cell lysate
      Lane 4 : HepG2 cell lysate
      Lane 5 : HeLa cell lysate

      Lysates/proteins at 10 µg per lane.

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

      Predicted band size: 40 kDa
      Observed band size: 67-75 kDa why is the actual band size different from the predicted?


    This product has been referenced in:

    • Walker DG  et al. Association of CD33 polymorphism rs3865444 with Alzheimer's disease pathology and CD33 expression in human cerebral cortex. Neurobiol Aging 36:571-82 (2015). WB ; Human . Read more (PubMed: 25448602) »
    • Teng E  et al. Dietary DHA supplementation in an APP/PS1 transgenic rat model of AD reduces behavioral and Aß pathology and modulates Aß oligomerization. Neurobiol Dis 82:552-60 (2015). WB ; Human . Read more (PubMed: 26369878) »
    See all 2 Publications for this product

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