FIGURE 3. (A) Caspase-3 activity is increased in HUVECs after 4-hour incubation with T/HS lymph. Whole cell extracts of HUVECS incubated in medium, T/HS, or T/SS lymph were prepared and standardized to 10 μg of protein. An ApoAlert kit (Clontech) was used to detect Caspase-3 activity. The amount of fluorescence correlates with caspase-3 activity. Data expressed as mean ± SD. *P < 0.05 versus all groups; n = 5 for T/HS and T/SS, and n = 3 for medium control. (B) Incubation with T/HS lymph but not T/SS lymph results in cleavage of caspase 3. Equal amounts of whole cell extracts (10 μg) prepared from cells treated with T/SS and T/HS lymph were resolved by SDS-PAGE and probed with anticleaved caspase-3 antibody. These results are representative of 3 independent studies.