Final answer:
Immunohistochemistry (IHC) is a biological technique that uses antibodies to detect specific proteins within tissue sections and is instrumental in disease diagnosis, particularly in tumor and cancer detection.
Step-by-step explanation:
Immunohistochemistry (IHC) is a staining technique that uses antibodies to detect specific proteins in tissues, a key application in the molecular basis of disease diagnosis and treatment. This technique relies on the principle that antibodies have high specificity for their antigens, allowing IHC to provide precise localization of proteins within various cell types in the tissue context. By labeling the antibodies with enzymes or fluorochromes, IHC allows for the visualization of protein distribution in tissue sections. This method is valuable in a wide range of applications, including tumor and cancer detection, analyzing mixtures of complex antigens, determining the structure of cell membranes and membrane proteins, and studying diseases, such as AIDS, which rely on the understanding of cellular components like CD8 cells.
IHC is distinct from similar techniques such as immunocytochemistry (ICC), which studies cells rather than whole tissues and requires further processing of cells to allow antibodies to enter and bind to intracellular targets. Techniques like ICC and immunofluorescence extend the applications of antibody-based assays in cellular and molecular biology.