XenoScreen XL YES YAS is a ready to use estrogen and androgen receptor transactivation test kit for the identification of  chemicals, agrochemicals, cosmetics (EDC's) or water samples with endocrine disruptive activity, i.e estrogenic and androgenic activity or antagonistic activity.  In the receptor transactivation test a chemical is required to bind to the receptor and to activate the receptor. In compliance with OECD Guideline TG455 and ISO 19040. The kit can also be used for measurement of agonistic activity only allowing the measurement of 8 compounds.

Many endocrine disrupting chemicals adversely impact the estrogen or androgen signaling by interacting with estrogen or androgen receptors. The receptors show ligand selectivity and target gene regulation, they modulate metabolic enzymes that are critical for normal estrogen or androgen synthesis and metabolism. Typical EDC's are e.g. phytoestrogens, bisphenolics, and organochlorine pesticides. Many endocrine discrupting chemicals act through multiple mechanisms and therefore biological effects of EDCs need to be carefully interpreted.

In the receptor transcriptional activation assay, YES (Yeast Estrogen Screen) and YAS (Yeast Androgen Screen) cells are exposed to 8 concentrations of a test sample, as well as a positive and a negative control, for 18 hours (XenoScreen XL YES YAS). After exposure, the receptor mediated β-galactosidase expression is assessed via a chromogenic substrate. Each dose is tested in duplicate to allow for statistical analysis of the data.

A dose-dependent and significant increase or decrease in the color development relative to the corresponding negative control upon exposure indicates that the sample acts as an endocrine disruptor. Comparison with standardized positive controls (tested in multiple doses) allows for a quantification of the endocrine disrupting properties in terms of EC10, EC50 of EEQ/AEQ.

XenoScreen XL YES YAS includes lyticase for a higher sensitivity as compared to the XenoScreen YES YAS. XL stands for Extra Lyticase, which is responsible for higher signals of the β-galactosidase activity leading to higher sensitivity.    

Characteristics

• Includes all media, controls, also quality controlled plastic ware
• Number of samples: 4 samples in 4 different receptors (ER, AR, Agonist and Antagonist), in duplicates, 8 dilutions or for 32 samples in 4 different receptors in 1 dilution. Allows for measurement of only 1 receptor activity whereby 4 times more samples can be measrued.
• Excel calculation sheet is available free of charge to support result Interpretation
• Includes Lyticase 
• Strains are not included in the kit and are available separately.

Also available

• YES (Yeast Estrogen Screen) Strain for max. 20 passages, art.no. N05-230-E (not included in the kit)
• YAS (Yeast Andogen Screen) Strain for max. 20 passages, art.no. N05-230-A (not included in the kit)
• YES YAS Culture Maintenance for growing the cells, art.no. N05-PMY-7
• XenoScreen XL YES test kit for the determination of estrogen agonistic activity, art.no. N32-233-Y
• XenoScreen XL YAS test kit for the determination of androgen agonistic activity, art.no. N32-234-Y