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14298S 100 µl (50 tests) $329.00


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H Endogenous Rabbit IgG

Immunofluorescence (Immunocytochemistry)

Confocal immunofluorescent analysis of NK-92 (positive, left) and K-562 (negative, right) cells using T-bet/TBX21 XP® (D6N8B) Rabbit mAb (green) and β-Actin (8H10D10) Mouse mAb #3700 (red).

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Flow Cytometry

Flow cytometric analysis of human PBMCs using T-Bet/TBX21 (D6N8B) XP® Rabbit mAb (Alexa Fluor® 488) co-stained with anti-CD56 (NK cells) and anti-CD19 (B cells) antibodies. T-bet/TBX21 is clearly expressed on the CD56+ NK cell population (left plot) and absent on the CD19+ B cells (right plot).

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Immunofluorescence (Immunocytochemistry)

A. Solutions and Reagents

NOTE: Prepare solutions with reverse osmosis deionized (RODI) or equivalently purified water.

  1. 20X Phosphate Buffered Saline (PBS): (9808) To prepare 1L 1X PBS: add 50 ml 20X PBS to 950 ml dH2O, mix. Adjust pH to 8.0.
  2. Formaldehyde: 16%, methanol free, Polysciences, Inc. (cat# 18814), use fresh and store opened vials at 4°C in dark, dilute in 1X PBS for use.
  3. Methanol, 100%
  4. Blocking Buffer (1X PBS / 5% normal goat serum (#5425) / 0.3% Triton™ X-100): To prepare 10 ml: add 0.5 ml normal goat serum and 0.5 ml 20X PBS to 9.0 ml dH2O, mix. While stirring, add 30 µl Triton™ X-100.
  5. Antibody Dilution Buffer (1X PBS / 1% BSA / 0.3% Triton X-100): To prepare 10 ml, add 30 µl Triton™ X-100 to 10 ml 1X PBS. Mix well then add 0.1 g BSA (9998), mix.
  6. Prolong® Gold AntiFade Reagent (#9071), Prolong® Gold AntiFade Reagent with DAPI (#8961).

B. Specimen Preparation - Cultured Cell Lines (IF-IC)

NOTE: Cells should be grown, treated, fixed and stained directly in multiwell plates, chamber slides or on coverslips.

  1. Aspirate liquid, then cover cells to a depth of 2–3 mm with 4% formaldehyde in 1X PBS.
    NOTE: Formaldehyde is toxic, use only in fume hood.
  2. Allow cells to fix for 15 minutes at room temperature.
  3. Aspirate fixative, rinse three times in 1X PBS for 5 minutes each.
  4. Proceed with Immunostaining (Section C).

C. Immunostaining

NOTE: All subsequent incubations should be carried out at room temperature unless otherwise noted in a humid light-tight box or covered dish/plate to prevent drying and fluorochrome fading.

  1. Methanol Permeabilization Step: Cover cells with ice-cold 100% methanol (use enough to cover completely to a depth of 3–5 mm, DO NOT LET DRY), incubate in methanol for 10 minutes at –20°C, rinse in 1X PBS for 5 minutes.
  2. Block specimen in Blocking Buffer for 60 minutes.
  3. While blocking, prepare primary antibody by diluting as indicated on datasheet in Antibody Dilution Buffer.
  4. Aspirate blocking solution, apply diluted primary antibody.
  5. Incubate overnight at 4°C.
  6. Rinse three times in 1X PBS for 5 minutes each.
  7. Coverslip slides with Prolong® Gold Antifade Reagent (#9071), Prolong® Gold AntiFade Reagent with DAPI (#8961).
  8. For best results examine specimens immediately using appropriate excitation wavelength. For long term storage, store slides flat at 4°C protected from light.

posted November 2006

revised December 2010

Protocol Id: 220

Flow Cytometry

NOTE: Prepare solutions with Milli-Q or equivalently purified water.

  1. 1X Phosphate Buffered Saline (PBS): Dissolve 8 g NaCl, 0.2 g KCl, 1.44 g Na2HPO4 and 0.24 g KH2PO4 in 800 ml dH2O. Adjust the pH to 7.4 with HCl and the volume to 1 L. Store at room temperature.
  2. Absolute Methanol
  3. Incubation Buffer: Dissolve 0.5 g bovine serum albumin (BSA) in 100 ml 1X PBS. Store at 4°C.
  4. Permeabilization Buffer: 0.5% Triton X-100, 0.2 µg/ml EDTA and 1% BSA in PBS.
  5. Recommended Anti-Mouse secondary antibodies::

A. Isolation of Cells and Fixation

  1. Collect cells by centrifugation and aspirate supernatant.
  2. Resuspend cells briefly in 100 µl PBS.
  3. Add 500 µl of permeabilization buffer. Incubate for 15 minutes on ice.
  4. Add 3 ml of ice-cold 100% methanol and mix on and off for 10 minutes.
  5. Proceed with staining or store cell at -20°C.

B. Immunostaining

NOTE: Account for isotype matched controls for monoclonal antibodies or species matched IgG for polyclonal antibodies. Count cells using a hemocytometer or alternative method.

  1. Aliquot 0.5–1x106 cells into each assay tube (by volume).
  2. Add 2–3 ml Incubation Buffer to each tube and rinse by centrifugation. Repeat.
  3. Resuspend cells in 100 µl Incubation Buffer per assay tube.
  4. Block in Incubation Buffer for 10 minutes at room temperature.
  5. Add the fluorochrome-conjugated primary antibody at the appropriate dilution to the assay tubes (see individual antibody datasheet for the appropriate dilution).
  6. Incubate for 1 hour at room temperature.
  7. Rinse as before in Incubation Buffer by centrifugation.
  8. Resuspend cells in 0.5 ml PBS and analyze on flow cytometer.
  9. Incubate for 30 minutes at room temperature.
  10. Rinse as before in Incubation Buffer by centrifugation.
  11. Resuspend cells in 0.5 ml PBS and analyze on flow cytometer; alternatively, for DNA staining, proceed to step C1.

C. Optional DNA Stain

  1. Resuspend cells in 0.5 ml of DNA dye (e.g. Propidium Iodide (PI)/RNase Staining Solution #4087).
  2. Incubate for at least 5 minutes at room temperature.

Analyze cells in DNA stain on flow cytometer.

posted April 2012

Protocol Id: 45

Product Usage Information

Application Dilutions
Immunofluorescence (Immunocytochemistry) 1:200
Flow Cytometry 1:50

Storage: Supplied in PBS (pH 7.2), less than 0.1% sodium azide and 2 mg/ml BSA. Store at 4°C. Do not aliquot the antibody. Protect from light. Do not freeze.

Specificity / Sensitivity

T-Bet/TBX21 (D6N8B) XP® Rabbit mAb (Alexa Fluor® 488 Conjugate) recognizes endogenous levels of total T-Bet/TBX21 protein.

Species Reactivity: Human

Source / Purification

Monoclonal antibody is produced by immunizing animals with a synthetic peptide corresponding to residues surrounding Gly465 of human T-Bet/TBX21 protein.

Product Description

This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated T-bet/TBX21 (D6N8B) XP® Rabbit mAb #13232.

The T-box gene family consists of transcription factors characterized by a related DNA-binding domain (T-box) of approximately 200 amino acids (1,2). The T-box genes exhibit diverse temporal and spatial patterns in the developing embryo. Studies have demonstrated members of this family play crucial roles during embryogenesis in a wide range of organisms by regulating cell fate decisions to establish the early body plan and to regulate later processes underlying organogenesis (3-5). Mutations in T-box genes are associated with many developmental defects (6). Recent studies also indicate potential roles in cancer by members of T-box family (7-9).

1.  Wilkinson, D.G. et al. (1990) Nature 343, 657-9.

2.  Papaioannou, V.E. and Silver, L.M. (1998) Bioessays 20, 9-19.

3.  Showell, C. et al. (2004) Dev Dyn 229, 201-18.

4.  Papaioannou, V.E. (2001) Int Rev Cytol 207, 1-70.

5.  Hoogaars, W.M. et al. (2007) Cell Mol Life Sci 64, 646-60.

6.  Baldini, A. (2004) Curr Opin Cardiol 19, 201-4.

7.  Abrahams, A. et al. (2010) IUBMB Life 62, 92-102.

8.  Rowley, M. et al. (2004) J Mammary Gland Biol Neoplasia 9, 109-18.

9.  Yang, X.R. et al. (2009) Nat Genet 41, 1176-8.

Entrez-Gene Id 30009
Swiss-Prot Acc. Q9UL17

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
XP is a registered trademark of Cell Signaling Technology, Inc.
Alexa Fluor is a registered trademark of Life Technologies Corporation.
The Alexa Fluor dye conjugates in this product are sold under license from Life Technologies Corporation, for research use only excluding use in combination with DNA microarrays and high content screening (HCS).
This product is provided under an intellectual property license from Life Technologies Corporation. The transfer of this product is contingent on the buyer using the purchased product solely in research, including use with HCS or other automated imaging applications but excluding use in combination with DNA microarrays. The buyer must not sell or otherwise transfer this product or its components for (a) diagnostic, therapeutic or prophylactic purposes; (b) testing, analysis or screening services, or information in return for compensation on a per-test basis; (c) manufacturing or quality assurance or quality control, or (d) resale, whether or not resold for use in research. For information on purchasing a license to this product for purposes other than as described above, contact Life Technologies Corporation, 5791 Van Allen Way, Carlsbad, CA 92008 USA or

T-Bet/TBX21 (D6N8B) XP® Rabbit mAb (Alexa Fluor® 488 Conjugate)