Immunohistochemistry

What it is

Immunohistochemistry (IHC) is a laboratory technique that uses specially designed antibodies to detect specific proteins in tumor tissue, revealing their presence and location on the microscope slide. In gliomas, IHC is used to identify molecular features such as the common IDH mutation and ATRX loss.

Understanding Immunohistochemistry

IHC works by applying antibodies that bind to a particular protein and then making that binding visible as a color on the tissue. This allows a pathologist to see, directly on the slide, whether a certain protein is present, absent, or altered. In glioma diagnosis, IHC can detect the most common IDH mutation (IDH1 R132H) with a specific antibody, show whether ATRX is retained or lost (helping distinguish astrocytoma from oligodendroglioma), and assess other markers. IHC is widely available, relatively fast, and complements genetic tests (such as sequencing), which are used when IHC is negative or inconclusive. Understanding immunohistochemistry clarifies a practical staining technique that reveals key glioma markers directly on tissue.

Why it matters

Understanding immunohistochemistry helps patients and families see one of the practical tools behind their diagnosis — a staining technique that detects key markers like IDH and ATRX directly on the tumor tissue.