An Introduction to Multiplex Immunohistochemistry - Part 1 of 4
Jane Naberhuis, Ph.D.
Article
With the advancement of immunotherapeutics, the urge to understand the tumor microenvironment has never been more pressing. Immunohistochemistry is a powerful tool used to examine protein expression, distribution, and activation in situ. Antibodies specific to an antigen of interest are used to detect the antigen in thin sections of flash frozen or formalin-fixed paraffin-embedded tissue. Visualization of the antigen is achieved using either an enzymatic reaction that induces chromogen precipitation at the site of antibody-antigen binding, or fluorescent reporters. Fluorescent reporters may be directly conjugated to the primary antibody used to detect the antigen of interest (direct immunofluorescence), or may be attached to a secondary antibody that detects the species-specific primary antibody (indirect immunofluorescence). The latter is more common, as it achieves more sensitive antigen detection.
