Immunogen
carcinoembryonic antigen (CEA) isolated from a human colon adenocarcinoma cell line.
Specificity
The antibody reacts specifically with human CEA (CD66e, 180 kDa) from several types of malignant tissue including colorectal, lung and breast tumors. It also stains medullary carcinomas of the thyroid. The product reacts strongly with the cell surface and cytoplasm of malignant glands in colorectal adenocarcinomas. A weak reactivity is seen with normal colon mucosa and occasionally with bile canalicular and pancreatic acinar cells, but not with other tested tissue including term placenta. There is no cross-reactivity with non-specific cross-reacting antigen (NCA) present in granulocytes, using immunoblotting, flow cytometry and immunohistochemical techniques. The antibody recognizes an epitope that is resistant to 30 minute oxidation by 1% sodium periodate solution in routine formalin-fixed and paraffin-embedded tissue sections. Enzymatic predigestion with proteolytic enzymes improves immunohistochemical staining with the antibody.