Tyramide Signal Amplification

Tyramide signal amplification (TSA), sometimes called Catalyzed Reporter Deposition (CARD), is a highly sensitive method enabling the detection of low-abundance targets in fluorescent immunocytochemistry (ICC), immunohistochemistry (IHC), and in situ hybridization (FISH) applications.

TSA involves horseradish peroxidase (HRP)-catalyzed deposition of tyramide on and near a target protein or nucleic acid sequence in situ. In the presence of low concentrations of H₂O₂, HRP is able to convert a labeled tyramide substrate into a highly reactive form that can covalently bind to tyrosine residues on proteins at or near the HRP. This generates high density tyramide labeling and is the reason for the exceptional sensitivity of this system. Tyramide can be labeled with a fluorophore or a hapten (such as biotin or DNP).

Multiple rounds of tyramide signal amplification can be performed for multicolor detection (see Figure 2 and our Tech Tip: Multicolor Fluorescence Imaging using Tyramide Amplification Kits). When TSA followed by antibody removal is used for multiplex fluorescent IHC, TSA not only facilitates detection of low-abundance targets, but also simplifies antibody panel design because primary antibodies of choice may be used, irrespective of host species or isotype.

Advantages of Tyramide Signal Amplification:

• Detect low-abundance targets
• Compatible with ICC, IHC and FISH
• Sensitivity up to 100-fold that of conventional methods
• Similar workflow to conventional ICC, IHC and FISH
• Use less primary antibody
• Simplified primary antibody panel design for multiplex IHC

Tyramide Signal Amplification Kits:

• Our kits provide all critical reagents for tyramide labeling
• Choose your tyramide: biotin tyramide or one of six CF® Dye tyramides
• Choose your HRP conjugate: goat anti-mouse, goat anti-rabbit, or streptavidin
• Kits also include Amplification Buffer and BSA for blocking

Tyramide Amplification Buffers:

• Tyramide Amplification Buffer Plus has enhanced sensitivity for tyramide signal amplification. It has improved brightness, specificity, and sensitivity over our original buffer below.
• Ready-to-Use Tyramide Amplification Buffer was our original buffer formulation, and has been replaced with the above buffer. The one advantage of this buffer is that there is no need to add hydrogen peroxide.

Tyramide Signal Amplification Kits