• Product nameAnti-IRF3 antibody
    See all IRF3 primary antibodies
  • Description
    Rabbit polyclonal to IRF3
  • Specificityab25950 recognises IRF3.
  • Tested applicationsSuitable for: IHC-P, ICC/IF, ELISA, WBmore details
  • Species reactivity
    Reacts with: Mouse, Human
  • Immunogen

    A synthetic peptide corresponding to 14 amino acids near the carboxyterminus of IRF3 (Human)

  • Positive control
    • Ramos whole cell lysate Mouse kidney This antibody gave a positive result when used in the following formaldehyde fixed cell lines: MCF-7.



Our Abpromise guarantee covers the use of ab25950 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
IHC-P Use a concentration of 2 µg/ml.
ICC/IF Use a concentration of 1 µg/ml.
ELISA Use at an assay dependent concentration.
WB Use a concentration of 1 - 2 µg/ml. Detects a band of approximately 44 kDa (predicted molecular weight: 47 kDa).Can be blocked with Human IRF3 peptide (ab39792).


  • FunctionMediates interferon-stimulated response element (ISRE) promoter activation. Functions as a molecular switch for antiviral activity. DsRNA generated during the course of an viral infection leads to IRF3 phosphorylation on the C-terminal serine/threonine cluster. This induces a conformational change, leading to its dimerization, nuclear localization and association with CREB binding protein (CREBBP) to form dsRNA-activated factor 1 (DRAF1), a complex which activates the transcription of genes under the control of ISRE. The complex binds to the IE and PRDIII regions on the IFN-alpha and IFN-beta promoters respectively. IRF-3 does not have any transcription activation domains.
  • Tissue specificityExpressed constitutively in a variety of tissues.
  • Sequence similaritiesBelongs to the IRF family.
    Contains 1 IRF tryptophan pentad repeat DNA-binding domain.
  • Post-translational
    Constitutively phosphorylated on many serines residues. C-terminal serine/threonine cluster is phosphorylated in response of induction by IKBKE and TBK1. Ser-385 and Ser-386 may be specifically phosphorylated in response to induction. An alternate model propose that the five serine/threonine residues between 396 and 405 are phosphorylated in response to a viral infection. Phosphorylation, and subsequent activation of IRF3 is inhibited by vaccinia virus protein E3.
    Ubiquitinated; ubiquitination involves RBCK1 leading to proteasomal degradation. Polyubiquitinated; ubiquitination involves TRIM21 leading to proteasomal degradation.
    ISGylated by HERC5 resulting in sustained IRF3 activation and in the inhibition of IRF3 ubiquitination by disrupting PIN1 binding. The phosphorylation state of IRF3 does not alter ISGylation.
  • Cellular localizationCytoplasm. Nucleus. Shuttles between cytoplasmic and nuclear compartments, with export being the prevailing effect. When activated, IRF3 interaction with CREBBP prevents its export to the cytoplasm.
  • Information by UniProt
  • Database links
  • Alternative names
    • IIAE7 antibody
    • Interferon regulatory factor 3 antibody
    • IRF 3 antibody
    • IRF-3 antibody
    • IRF3 antibody
    • IRF3_HUMAN antibody
    • MGC94729 antibody
    see all

Anti-IRF3 antibody images

  • ab25950 stained MCF-7 cells. The cells were 4% formaldehyde fixed (10 min) and then incubated in 1%BSA / 10% normal goat serum / 0.3M glycine in 0.1% PBS-Tween for 1h to permeabilise the cells and block non-specific protein-protein interactions. The cells were then incubated with the antibody ab25950 at 1µg/ml overnight at +4°C. The secondary antibody (green) was DyLight® 488 goat anti- rabbit (ab96899) IgG (H+L) used at a 1/1000 dilution for 1h. Alexa Fluor® 594 WGA was used to label plasma membranes (red) at a 1/200 dilution for 1h. DAPI was used to stain the cell nuclei (blue) at a concentration of 1.43µM.

  • Immunofluorescence of IRF3 in Mouse Kidney cells using ab25950 at 20 ug/ml.

  • Lane 1 : Anti-IRF3 antibody (ab25950) at 1 µg/ml
    Lane 2 : Anti-IRF3 antibody (ab25950) at 2 µg/ml
    Lane 3 : Anti-IRF3 antibody (ab25950) at 4 µg/ml

    Lane 1 : Ramos whole cell lysate.
    Lane 2 : Ramos whole cell lysate.
    Lane 3 : Ramos whole cell lysate.

    Predicted band size : 47 kDa
    Observed band size : ~44 kDa (why is the actual band size different from the predicted?)
  • ab25950 at 2µg/ml staining IRF3 in mouse kidney by IHC.

References for Anti-IRF3 antibody (ab25950)

This product has been referenced in:
  • Kim JH  et al. Inhibitory effects of an aqueous extract from Cortex Phellodendri on the growth and replication of broad-spectrum of viruses in vitro and in vivo. BMC Complement Altern Med 16:265 (2016). WB ; Mouse . Read more (PubMed: 27484768) »
  • Garcia PV  et al. Increased toll-like receptors and p53 levels regulate apoptosis and angiogenesis in non-muscle invasive bladder cancer: mechanism of action of P-MAPA biological response modifier. BMC Cancer 16:422 (2016). WB, IHC . Read more (PubMed: 27389279) »

See all 9 Publications for this product

Product Wall

Application Western blot
Sample Human Cell lysate - other (HT-29)
Gel Running Conditions Reduced Denaturing (10)
Loading amount 30 µg
Specification HT-29
Blocking step BSA as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: RT°C

Abcam user community

Verified customer

Submitted Jan 18 2017

Application Western blot
Sample Mouse Cell lysate - whole cell (mouse hepatocytes)
Gel Running Conditions Reduced Denaturing
Loading amount 20 µg
Treatment 20 ug/ml poly(I:C) for 24 hours
Specification mouse hepatocytes
Blocking step Milk as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: 23°C

Abcam user community

Verified customer

Submitted Sep 08 2015

Application ChIP
Detection step Real-time PCR
Sample Mouse Cell lysate - nuclear (Fibroblast)
Specification Fibroblast
Negative control Bead-only as negative control for antibody and primer set amplifying TBP promoter as qPCR negative control.
Type Cross-linking (X-ChIP)
Duration of cross-linking step: 10 minute(s) and 0 second(s)
Specification of the cross-linking agent: 1% Paraformaldehyde (EMS)
Positive control Abcam ab7970 (p65 antibody) as positive control for antibody and primer set amplifying ISG15 promoter as the positive control for the qPCR.

Nima Mohaghegh

Verified customer

Submitted Feb 27 2014

We have only tested the antibody in a reduced, denatured Western blot. We are not sure whether it will bind to a dimer in a native Western blot. It is possible, but it's also possible that the epitope of the antibody (located in the C-terminus) will be...

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