Comparison of live and heat-inactivated bacteria. A dose-dependent increase of granulocyte CR3 (CD11b/CD18) expression and oxidative burst was observed in lepirudin-anticoagulated human whole blood after stimulation for 10 minutes at 37°C. Results for live log-phase and heat-inactivated meningococci were similar. MFI indicates median fluorescence intensity; B, baseline (unstimulated sample) at time of incubation (t = 0) and after 10 minutes (t = 10). The experiment was repeated once with virtually identical results.