How is Immunohistochemistry Used in Pathological Diagnosis?

Immunohistochemistry (IHC) is a powerful tool in histology, used to detect specific proteins within tissue sections. By using antibodies that bind to antigens in the tissue, IHC can reveal the presence and distribution of certain proteins, helping to classify tumors and identify infectious agents. For example, the presence of estrogen receptor (ER) and progesterone receptor (PR) in breast cancer cells can guide treatment decisions. IHC is also used to detect viral proteins, aiding in the diagnosis of viral infections.