Immunostaining of mouse atherosclerotic lesions.

Atherosclerotic lesions develop through interactions with diverse cell types whose functions are determined by a complex array of regulators. Immunostaining is now a commonly applied technique to identify these numerous cell types and regulators in lesions. The principle of the technique is that an antibody is incubated with the tissue under conditions that favor a specific interaction with its antigen. This is subsequently visualized most commonly by a chromogenic substrate that produces a colored precipitate at the location of the antigen-antibody interaction. When appropriately applied, it is a powerful technique to provide mechanistic insight into the atherogenic process. However, the complexity of atherosclerotic tissue can provide challenges to ensuring that development of the chromogen is due to specific antigen-antibody interaction. Thus, the determination of specific interactions frequently requires the judicious use of appropriate control experiments.