Comparative study of apoptosis-detecting techniques: TUNEL, apostain, and lamin B

The mechanism of the apoptotic process is generally recognized as being highly intricate. Unfortunately, so is its detection. The concept of detection sensitivity reflects not only the ability of a particular technique to label most of the cells displaying the appropriate marker but also the possibility of labeling cells in the earliest phase of the apoptotic process. For this study, we chose three techniques, visualized by means of immunohistochemistry: terminal dUTP-transferase-mediated nick end labeling (TUNEL), apostain, and lamin B. The number of apoptotic cells detected in the observed specimens with respect to the used technique differed for the majority of cases. The lowest apoptotic indices were usually obtained by the lamin B technique, the TUNEL technique followed, and the apostain technique gave the highest values. The comparison revealed that the TUNEL and apostain techniques were positively correlated in the majority of specimens observed. The linear correlation between TUNEL/apostain and lamin B was weaker. TUNEL, apostain, and lamin B techniques, variant in principle, give different yet correlating results, which is in accordance with the assumption that they describe the same phenomenon detected at different time periods of the apoptotic process.