Flow cytometric analysis of K562 cells, untreated (green) or treated with Gleevec (10uM, 2hr; blue) using Phospho-Tyrosine Mouse mAb (P-Tyr-100) (Alexa Fluor® 488 Conjugate) (solid lines) or concentration-matched Mouse (MOPC-21) mAb IgG1 Isotype Control (Alexa Fluor® 488 Conjugate) #4878 (dashed lines).
Cell Signaling Technology Antibody conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometric analysis of human cells.
*The unconjugated antibody, #9411, reacts with phospho-tyrosine in all species tested. CST expects that Phospho-Tyrosine Mouse mAb (P-Tyr-100) (Alexa Fluor® 488 conjugate) will also recognize phospho-tyrosine in all species.
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.
All reagents required for this protocol may be efficiently purchased together in our Intracellular Flow Cytometry Kit (Methanol) #13593, or individually using the catalog numbers listed below.
NOTE: Prepare solutions with reverse osmosis deionized (RODI) or equivalent grade water.
NOTE: When including fluorescent cellular dyes in your experiment (including viability dyes, DNA dyes, etc.), please refer to the dye product page for the recommended protocol. Visit www.cellsignal.com for a full listing of cellular dyes validated for use in flow cytometry.
NOTE: Adherent cells or tissue should be dissociated and in single-cell suspension prior to fixation.
NOTE: Optimal centrifugation conditions will vary depending upon cell type and reagent volume. Generally, 150-300g for 1-5 minutes will be sufficient to pellet the cells.
NOTE: If using whole blood, lyse red blood cells and wash by centrifugation prior to fixation.
NOTE: Antibodies targeting CD markers or other extracellular proteins may be added prior to fixation if the epitope is disrupted by formaldehyde and/or methanol. The antibodies will remain bound to the target of interest during the fixation and permeabilization process. However, note that some fluorophores (including PE and APC) are damaged by methanol and thus should not be added prior to permeabilization. Conduct a small-scale experiment if you are unsure.
NOTE: Count cells using a hemocytometer or alternative method.
posted July 2009
revised June 2020
Protocol Id: 407
Phospho-Tyrosine Mouse mAb (P-Tyr-100) is a high affinity antibody. ELISAs against a wide variety of phosphopeptides indicate that (a) P-Tyr-100 binds phospho-Tyr in a manner largely independent of the surrounding amino acid sequence. 2D gel Western blot analysis of pervanadate-treated cell extracts also shows that P-Tyr-100 interacts with a broad range of tyrosine-phosphorylated proteins. P-Tyr-100 does not cross-react with peptides containing phospho-serine or phospho-threonine. (U.S. Patent No's.: 6,441,140; 6,982,318; 7,259,022; 7,344,714; U.S.S.N. 11,484,485; and all foreign equivalents.)
All Species Expected
Monoclonal antibody is produced by immunizing animals with phospho-tyrosine-containing peptides . The antibody was conjugated to Alexa Fluor® 488 under optimal conditions with an F/P ratio of 2-6.
Tyrosine phosphorylation plays a key role in cellular signaling (1). Research studies have shown that in cancer, unregulated tyrosine kinase activity can drive malignancy and tumor formation by generating inappropriate proliferation and survival signals (2). Antibodies specific for phospho-tyrosine (3,4) have been invaluable reagents in these studies. The phospho-tyrosine monoclonal antibodies developed by Cell Signaling Technology are exceptionally sensitive tools for studying tyrosine phosphorylation and monitoring tyrosine kinase activity in high throughput drug discovery.