MPO and NE activities (mean ± SEM) of skin extracts from NE–/– mice injected intradermally with pathogenic rabbit anti-mBP180 IgG. Neonatal NE–/– (bars 1–3) and NE+/+ (bars 4–6) mice received 2.5 mg/g body weight anti-mBP180 IgG. MPO (a) and NE (b) activities in skin at the injection sites were assayed 4 hours (bars 2 and 5 in a; bars 1 and 3 in b) or 12 hours (bars 1, 3, 4, and 6 in a; bars 2 and 4 in b) after IgG administration. n = 8 for NE–/– and NE+/+ groups. *P < 0.01; **P < 0.001. Student t test for paired samples (bar 2 vs. 5, bar 3 vs. 6 in a; bar 1 vs. 3, bar 2 vs. 4 in b).