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CD45 (136-4B5) Mouse mAb #3575
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Gallery: CD45 (136-4B5) Mouse mAb #3575
A. Solutions and Reagents
NOTE: Prepare solutions with reverse osmosis deionized (RODI) or equivalent grade water.
- Ethanol, anhydrous denatured, histological grade (100% and 95%).
- Deionized water (dH2O).
- Hematoxylin (optional).
- Wash Buffer:
- 1X Tris Buffered Saline with Tween® 20 (TBST): To prepare 1L 1X TBST add 100 ml 10X Tris Buffered Saline with Tween® 20 (#9997) to 900 ml dH20, mix.
- SignalStain® Antibody Diluent (#8112).
- Antigen Unmasking Citrate: 10 mM Sodium Citrate Buffer: To prepare 1 L, add 2.94 g sodium citrate trisodium salt dihydrate (C6H5Na3O7â¢2H2O) to 1 L dH2O. Adjust pH to 6.0.
- 3% Hydrogen Peroxide: To prepare 100 ml, add 10 ml 30% H2O2 to 90 ml dH2O.
- Blocking Solution: TBST/5% Normal Goat Serum: to 5 ml 1X TBST, add 250 µl Normal Goat Serum (#5425).
- Detection System: SignalStain® Boost IHC Detection Reagents (HRP, Mouse #8125).
- Substrate: Vector® NovaRED™ (Vector Laboratories).
NOTE: Do not allow slides to dry at any time during this procedure.
- Deparaffinize/hydrate sections:
- Incubate sections in three washes of xylene for 5 min each.
- Incubate sections in two washes of 100% ethanol for 10 min each.
- Incubate sections in two washes of 95% ethanol for 10 min each.
- Wash sections two times in dH2O for 5 min each.
C. Antigen Unmasking
For Citrate: Bring slides to a boil in 10 mM sodium citrate buffer, pH 6.0; maintain at a sub-boiling temperature for 10 min. Cool slides on bench top for 30 min.
- Wash sections in dH2O three times for 5 min each.
- Incubate sections in 3% hydrogen peroxide for 10 min.
- Wash sections in dH2O two times for 5 min each.
- Wash sections in wash buffer for 5 min.
- Block each section with 100–400 µl blocking solution for 1 hr at room temperature.
- Remove blocking solution and add 100–400 µl primary antibody diluted in SignalStain® Antibody Diluent (#8112) to each section. Incubate overnight at 4°C.
- Equilibrate SignalStain® Boost Detection Reagent (HRP, Mouse #8125) to room temperature.
- Remove antibody solution and wash sections with wash buffer three times for 5 min each.
- Cover section with 1–3 drops SignalStain® Boost Detection Reagent (HRP, Mouse #8125) as needed. Incubate in a humidified chamber for 30 min at room temperature.
- Wash sections three times with wash buffer for 5 min each.
- Prepare Vector® NovaRED™ per manufacturer's recommendations.
- Apply 100-400 µl substrate to each section and monitor closely. 5-15 minutes generally provides an acceptable staining intensity.
- Immerse slides in dH2O.
- If desired, counterstain sections with hematoxylin per manufacturer’s instructions.
- Wash sections in dH2O two times for 5 min each.
- Dehydrate sections:
- Incubate sections in 95% ethanol two times for 10 sec each.
- Repeat in 100% ethanol, incubating sections two times for 10 sec each.
- Repeat in xylene, incubating sections two times for 10 sec each.
- Mount sections with coverslips.
posted February 2010
revised November 2013
protocol id: 287
Not recommended for use with fixation/permeabilization protocols that contain methanol.
CD45 (136-4B5) Mouse mAb detects endogenous levels of total CD45 protein.Species Reactivity: Human
Monoclonal antibody is produced by immunizing BALB/c mice with stimulated human leukocytes.
The protein phosphatase (PTP) receptor CD45 is a type I transmembrane protein comprised of a pair of intracellular tyrosine phosphatase domains and a variable extracellular domain generated by alternative splicing (1). The catalytic activity of CD45 is a function of the first phosphatase domain (D1) while the second phosphatase domain (D2) may interact with and stabilize the first domain, or recruit/bind substrates (2,3). CD45 interacts directly with antigen receptor complex proteins or activates Src family kinases involved in the regulation of T- and B-cell antigen receptor signaling (1). Specifically, CD45 dephosphorylates Src-family kinases Lck and Fyn at their conserved negative regulatory carboxy-terminal tyrosine residues and upregulates kinase activity. Conversely, studies indicate that CD45 can also inhibit Lck and Fyn by dephosphorylating their positive regulatory autophosphorylation site. CD45 appears to be both a positive and a negative regulator that conducts signals depending on specific stimuli and cell type (1). Human leukocytes including lymphocytes, eosinophils, monocytes, basophils, and neutrophils express CD45, while erythrocytes and platelets are negative for CD45 expression (4).
For Research Use Only. Not For Use In Diagnostic Procedures. Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.