HET-CAM
The HET-CAM , also known as the chicken egg test , is a method for checking the mucous membrane tolerance of chemicals. The abbreviation stands for hen's egg test on the chorionic allantoic membrane and is a CAM assay . The abbreviation is often derived from the English Hen's egg test on chorioallantoic membrane .
In the mid-1980s, the chicken and egg test on the chorionic allantoic membrane was developed to test the skin tolerance of chemicals. The chorionic allantoic membrane (CAM) is the choroid membrane of an egg. Chorion and allantois are fructose coats that surround the embryo in vertebrates. The membrane is permeated by blood vessels and is insensitive to pain. The test is carried out on incubated eggs before the 10th day of incubation. This ensures that the chicken embryo does not yet feel pain.
For the test, the substance to be tested is placed on the CAM. The reactions of the membrane (bleeding, changes in the blood vessels or the albumen) are observed and evaluated.
With the help of the HET-CAM, the frequency of the extremely controversial Draize test for checking the irritative effects of substances on the eyes and mucous membranes in rabbits' eyes ( rabbit eye test ) could be reduced. The method is valid but not yet validated and delivers results after 5 to 15 minutes. In Germany, the test is recognized as an official pre-test for testing mucosal tolerance. However, in Germany, HET-CAM is only allowed to replace the test on rabbit eyes in the case of strongly irritating substances. In France it is recognized as a complete alternative. Substances that are not assessed as strongly irritating in the HET-CAM must still be tested on rabbit eyes.
The HET-CAM was developed by the Osnabrück pharmacologist and toxicologist Niels-Peter Lüpke in 1985.
Individual evidence
- ^ University of Osnabrück newspaper, Prof. Lüpke: Legislative recognition of the HET-CAM test in France ( Memento from June 25, 2007 in the Internet Archive ), from July 10, 1997.
- ^ H Rietz: Pain-free testing . In: Ruprecht - Heidelberg student newspaper. May 15, 2007.
- ↑ NP Luepke: Hen's egg chorioallantoic membrane test for irritation potential. In: Fd Chem Toxic. Volume 23, 1985, pp. 287-291.
literature
- A. Elsner: Animal experiments: The relevance for humans is controversial . In: Deutsches Ärzteblatt . Volume 101, 2004, pp. A-2511 / B-2118 / C-2038.
- W. Steiling et al .: The HET-CAM, a Useful In Vitro Assay for Assessing the Eye Irritation Properties of Cosmetic Formulations and Ingredients. In: Toxicology in Vitro . Volume 13, 1999, pp. 375-384.
- L. Gilleron et al .: Evaluation of a modified HET-CAM assay as a screening test for eye irritancy. In: Toxicology in Vitro. Volume 10, 1996, pp. 431-446.
- TD Wilson, WF Steck: A modified HET-CAM assay approach to the assessment of anti-irritant properties of plant extracts. In: Food and Chemical Toxicology . Volume 38, 2000, pp. 867-872.
- WK Schlage et al .: Use of the HET-CAM Test for the Determination of the Irritant Potential of Cigarette Sidestream Smoke. In: Toxicology in Vitro. Volume 13, 1999, pp. 829-835.
- Z. Djabari et al .: The HET-CAM test combined with histological studies for better evaluation of active ingredient innocuity. In: International Journal of Tissue Reactions. Volume 24, 2002, pp. 117-121. PMID 12779245
- AH Brantner et al .: HET-CAM bioassay as in vitro alternative to the croton oil test for investigating steroidal and non-steroidal compounds. In: Alternatives to Animal Experiments. Volume 19, 2002, pp. 51-56. PMID 12098009