EpiQuik Circulating Acetyl Histone H3K18 ELISA Kit (Colorimetric)

The EpiQuik™ Circulating Acetyl Histone H3K18 ELISA Kit (Colorimetric) is a convenient package of tools that allows the experimenter to specifically measure circulating acetyl histone H3K18 (H3K18ac) from biological fluid samples such as plasma and serum from human, mouse or rat. The kit has the following advantages:

• Quick and efficient procedure, which can be finished within 2.5 hours.
• High sensitivity and specificity. The detection limit is as low as 0.5 ng/well with dynamic range of 1-20 ng/well within the indicated amount range of the plasma/serum. Only recognizes H3K18ac with no cross-reactivity with unmodified H3 or other modifications at the same lysine site.
• The control is conveniently included for the quantification of H3K18ac.
• Strip microplate format makes the assay flexible: manual or high throughput.
• Simple, reliable, and consistent assay conditions.

Background Information
Epigenetic activation or inactivation of genes plays a critical role in many important human diseases, especially in cancer. A major mechanism for epigenetic gene inactivation is methylation of CpG islands in genomic DNA caused by DNA methyltransferases. Histone acetyltransferases (HATs) and deacetylases (HDACs) control or regulate DNA methylation through chromatin-dependent transcriptional repression or activation. HATs transfer acetyl groups from acetyl CoA to the lysine residues of histone proteins. P300 is the major HAT that catalyzes acetylation of histone H3 at lysine 18 (H3K18) in mammalian cells. HDACs and SIRT1/7 are the major histone deacetylases that deacetylate H3K18. H3K18ac has been viewed as a signature mark of transcriptionally active genes, which is placed exclusively in the 5’- region downstream of the promoter. The H3K18ac can also be changed by inhibition or activation of HATs or HDAC/SIRTs. Circulating histone H3K18ac in plasma or serum has been observed and demonstrated as the marker for many different diseases or pathological changes such as cancer progression. Therefore, detection of circulating H3K18ac would provide useful information for a better understanding of epigenetic regulation of gene activation and silencing, histone modification-associated pathological processes, screening of disease-related biomarkers, as well as for developing histone modification-targeted drugs. 

Principle & Procedure
This kit is designed for measuring total H3K18acin plasma or serum. In an assay with this kit, the Histone H3 proteins acetylated at K18 in the plasma/serum sample are captured on the strip wells coated with anti-H3K18ac antibody. The captured H3K18ac proteins can be then recognized with detection antibody followed by a color development reagent. The ratio of H3K18ac is proportional to the intensity of absorbance. The absolute amount of H3K18ac can be quantitated by comparing to the standard control.

Starting Materials
Input materials should be plasma or serum. The amount of plasma or serum for each assay can be 10 to 40 µl with an optimal amount of 30 µl.