FIGURE 5.

a, In vivo PGP generation: in vivo PGP production was examined using MMPs or HNE with or without PE. Various proteases (50 μl) were administered intratracheally into murine (4- to 6-wk-old BALB/c mice) airways and bronchoalveolar lavage fluid was collected 24 h later. PGP levels were determined using ESI LC-MS/MS. PGP production was significantly increased in MMP-9 with PE (*, p < 0.05 vs PBS control; †, p < 0.05 vs MMP-9 alone) and MMP-8 with PE (*, p <0.05 vs PBS control; †, p <0.05 vs MMP-8 alone) compared with other proteases with or without PE. PBS control and PE alone had similar PGP production. Of note, aminophenylmercuric acetate alone (or in combination with PE) also did not generate PGP (data not shown). Number of mice per group = 6. b, PGP production correlated with neutrophil influx: PGP production levels (■) were compared with PMN counts ( ) in mice treated with a combination of the indicated protease and PE from Fig. 3a. There is a notable correlation between PGP production and PMN counts for each condition (R² = 0.996, inset).