AE1/AE3

Histopathology of a pelvic lymph node in a patient with endometrial adenocarcinoma (FIGO grade 1):
- Left panel shows H&E staining and low magnification, where any presence of small metastases is hard to see.
- Middle panel shows immunohistochemistry for CK AE1/AE3, which highlights even small tumor nests.
- The right panel shows high magnification on a positive area, confirming adenocarcinoma, as it shows tumor cells with large nuclei and prominent nucleoli.

AE1/AE3 is an antibody cocktail that is used in immunohistochemistry, being generally positive in the cytoplasm of carcinomas (cancers of epithelial origin).[1][2]

Targets

The antibody cocktail binds to cytokeratin 1 - 8, 10, 14 - 16 and 19 (but not CK17 or CK18).[1] It is therefore used as a marker of carcinomas, such as depth of invasion and metastases.[1] For example, it is both relatively sensitive and specific for detection of breast cancer metastasis to sentinel lymph nodes.[3]

It may cross-react with GFAP, leading to aberrant staining of glial tumors such as ependymoma, glioblastoma and schwannoma.[1] It may also stain myofibroblasts and smooth muscle cells.[1] Furthermore, it may stain nodal epithelial cells that has contaminated a tumor from recent biopsy.[1]

See also

• List of histologic stains that aid in diagnosis of cutaneous conditions

References

1. "Stains - Cytokeratin AE1 / AE3". PathologyOutlines. 2013-07-01. Revised: 26 November 2019
2. Cytoplasmic stain: "Pan Cytokeratin [AE1/AE3]". BioCare Medical. Retrieved 2021-05-12.
3. Xu X, Roberts SA, Pasha TL, Zhang PJ (2000). "Undesirable cytokeratin immunoreactivity of native nonepithelial cells in sentinel lymph nodes from patients with breast carcinoma". Arch Pathol Lab Med. 124 (9): 1310–3. doi:10.5858/2000-124-1310-UCIONN. PMID 10975928.