Application

The greater incorporation of Br-dUTP results in a stronger signal by flow cytometry when detected using a fluorescein-labeled anti-BrdU antibody.Propidium iodide/RNase A solution is included in the kit to counterstain the total DNA. APOBRDU has been used in flow cytometry assay in human non–small cell lung cancer. APOBRDU has been used in cell cycle and apoptosis assay in HeLa cells, and in tunel assay human neuroblastoma cell lines.

Features and Benefits

Greater incorporation of Br-dUTP, resulting in improved detection than found by using biotin- or digoxigenin-conjugated dUTP or by using fluorochrome (fluorescein or BODIPY)-conjugated deoxynucleotides.

Packaging

The kit is shipped in two parts, both wet ice. Upon receipt, store APO-PART1 at −20 °C and APO-PART2 at 2-4 °C

Principle

Br-dUTP is incorporated more readily into the DNA fragments than deoxyuridine triphosphate labeled with larger dyes such as FITC, biotin or digoxigenin. One of the biological characteristics that defines apoptosis is the degradation of genomic DNA into fragments of 180-200 bp, commonly called "DNA laddering". The fragmentation creates a large number of 3′-hydroxyl sites at the DNA breaks. This property is used in the APO-BRDU kit to identify apoptotic cells by labeling the 3′-hydroxyl sites with bromodeoxyuridine triphosphate (Br-dUTP). Br-dUTP is enzymatically attached to the 3-hydroxyl sites of double- or single-stranded DNA by terminal transferase (TdT). Non-apoptotic cells do not incorporate Br-dUTP due to the lack of available 3-hydroxyl sites.