• Eliminates ⁵¹Cr radioisotope for safer measurements
• Direct rapid labeling of apoptotic cells
• Concurrently quantitate apoptosis with SR-FLICA Kits
• Clearly distinguish apoptotic from necrotic cells

Without using ⁵¹Cr radioisotope, ICT's Cytotoxicity Test (CT) and Total Cytotoxicity Test (TCT) Kits provide a direct measurement of cytotoxicity, as opposed to an indirect indicator such as the release of LDH or ATP enzymes. The TCT Kit enables you to distinguish apoptosis from necrosis for more accurate assessment of cytolytic activity.

The kits utilize two stains: The green SFSE membrane stain separates the effector cells from the target cells by staining all the target cells green, and the red 7-AAD live/dead stain identifies cells killed by cytolytic activity by binding to the DNA of membrane-compromised cells. With ICT's TCT Kit, a unique additional reagent is also added to the target cells to measure apoptosis via detection of caspase activity, which enables you to obtain a higher percentage of overall cell death.

Figure 1: As all target cells were initially stained green, the entire population can be counted in R2+R1. After this initial staining, the red live/dead stain was added so all the dead target cells were stained red which shifted them up Y-axis (R2) and clearly distinguished them from the live target cells (R1). Live effector cells are in R4, dead effector cells are in R3.

Figure 2: Using the formula {R2/(R2+R1)} x 100, total cytotoxicity increases as more effector cells are combined with target cells (E/T ratios increase from 0:1 to 100:1). User Manual