What should you know about immunofluorescence and immunohistochemistry?

In immunohistochemistry, an antibody attaches to a target marker and produces a visible colour reaction in a tissue section. In immunofluorescence, the antibody carries a fluorescent tag that is seen with a specialised microscope. Both methods can show whether a marker is present and where it is located.

The methods may be used to identify cell types, investigate a tissue pattern, or assess a feature relevant to diagnosis. A pathologist interprets the staining with the tissue structure and your clinical information. A visible stain is not, by itself, a complete diagnosis.

The tissue usually comes from a Biopsy. Tell your team about earlier pathology, medicines, allergies, and treatments that could affect the sample or interpretation. Ask which marker is being tested and whether the laboratory may use one or both methods.

When the report is ready, ask whether the stain is present, where it appears, and how strongly the finding supports the proposed diagnosis. The Immunohistochemistry technology page provides further background. Your clinician can explain how the result fits with imaging and other tests.

These are laboratory methods, so any immediate concerns usually relate to collecting the tissue rather than the staining. Contact your care team if the biopsy area develops increasing redness, warmth, swelling, discharge, or pain, or if you develop fever.

Seek urgent help for uncontrolled bleeding, fainting, severe breathing difficulty, or swelling around the mouth or throat. Follow the specific aftercare instructions from the service that collected your sample.

Ask why the marker was selected, whether the tissue sample is sufficient, how immunofluorescence differs from the stain used in your report, and when the findings will be discussed. Ask what other results are needed before a diagnosis or treatment plan is confirmed.