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Journal of Clinical Pathology and Laboratory Medicine | Volume 3

July 05-06, 2019 | Paris, France

Pathology and Surgical Pathology

International Conference on

Tyramid amplification system, an old and unappreciated powerful immunohistochemistry

problem solving weapon. Hints for a simple and easy use of it

Maria L Loredo Mendoza

Universidad Panamericana, Mexico

he tyramide amplification system was first used in

immunohistochemistry in the decade of 1990, but has

never been very popular in spite of its capacity to increase

in an extraordinary way the sensitivity and specificity of the

regular immunostaining. The tyramide principle of action is

based on the reactivity of this molecule with horseradish

peroxidase (HRP) enzyme which causes a catalytic reporter

deposit in close vicinity to the epitope of interest. With this

system we are able to use primary antibodies at a very high

dilution which makes our immunolabeling more specific and

also less expensive. It is also capable of detecting molecules

that are very scarce or small or the ones that give weak

signaling in our tissue, as it highly increases the size and

intensity of the signal, enabling us to visualize a very precise

and enhanced label without loss of resolution or increase in

background. Other advantage of this amplification system

includes the possibility to do a dual immuno-labeling with

primary antibodies made in the same species, like the use of

two primaries from mouse. Regarding the protocol of use of

this technique, it is very important to utilize specific washing

and protein blocking buffers to prevent having background or

non specific binding. To do the tyramid systemmore versatile

is recommendable to have HRP conjugated streptavidin (SA-

HRP) which would favor the use of secondary biotinylated

antibodies and to have HRP conjugated anti-fluorescein, that

would allow to continue with the amplification step of an

already fluorescein labeled slide with a weak signal. Finally

the anti-fluorescein-HRP could be used with a fluorescein

conjugated tyramid reagent to do a chromogenic detection

without the need of a fluorescence microscope.