Researchers report of a novel method to detect an aggressive form of breast cancer that overproduce HER2-encoded proteins, using antibodies from chicken.

In a paper in the International Journal of Cancer, the NIST-NCI-SAIC research team found that chicken immunoglobulin Y (IgY) antibody created against the HER2 protein could be tagged with quantum dots (tiny, intense and tunable sources of colorful light) to more reliably detect the HER2 biomarker than the existing diagnostic tests using mammalian antibodies tagged with conventional fluorescent dyes. Overall, the improvement in sensitivity to the HER2 biomarker was about 40-50 percent.

The increased sensitivity of the HER2 quantum dot-based quantitative bioimaging system stems from the broad genetic differences between avian and human species. The chicken IgY antibody to HER2 reacts strongly with the target protein while ignoring other human proteins that can interfere with current diagnostic tests.

In photo: Immunohistochemical detection of HER2 cancer biomarker with IgY antibody and quantum dots is demonstrated in these samples of breast cancer cells from a patient with HER2 over expression. Cell nuclei are stained blue, quantum dots responding to the HER2 protein light up in bright red at the cell membranes. Treatment with trastuzumab could only be effective for the latter patient. Credit: NIST