TUNELtesztet

The TUNEL assay, which stands for Terminal deoxynucleotidyl transferase dUTP nick end labeling, is a common laboratory technique used to detect and quantify apoptosis, or programmed cell death, in cells and tissues. It works by identifying DNA fragmentation, a hallmark of late-stage apoptosis. The TUNEL assay utilizes an enzyme called terminal deoxynucleotidyl transferase (TdT). This enzyme catalyzes the addition of labeled nucleotides to the free 3' hydroxyl ends of fragmented DNA. The labels can be fluorescent dyes or haptens, which are then detected using microscopy or flow cytometry. The presence of these labeled nucleotides indicates that the DNA within the cell has been broken down, signifying apoptotic activity. The TUNEL assay is widely used in various research fields, including cancer biology, developmental biology, and neuroscience, to study the mechanisms and extent of cell death. It can be performed on both fixed and unfixed cells, and on tissue sections. While a valuable tool, it is important to note that DNA fragmentation can also occur in some non-apoptotic processes, so TUNEL results are often interpreted in conjunction with other indicators of apoptosis.