Figure 2

Interaction of CS-exposed A1AT with capsase-3. Energy (Kcal/mol) generated by the intermolecular interaction between human A1AT (100 µmol/L) added sequentially in 10-µL aliquots (for a total of 29 injections) at 540-s intervals to (A) elastase (positive control); (B) buffer (negative control); (C) caspase-3 (8.9 µmol/L); or between (D) human A1AT preexposed to CS extract (25%) and caspase-3. The energy was measured with an isothermal titration microcalorimeter at 30°C and expressed in relation to the molar ratio of the two reaction components, defined as the ratio of injected reactant to cell solution. Representative of two independent experiments.