Figure 10. In vivo protective activity of CR6261 against wild type H5N1 and H1N1 strains.

Kaplan-Meier survival curves of BALB/c mice were injected (i.p.) with CR6261 or irrelevant control (15 mg/kg) then challenged 24 h later (i.n.) with (a) 10 LD₅₀ of A/Vietnam/1203/04 (n = 5) or (b) 25 LD₅₀ A/WSN/33 (n = 10) and observed daily for a period of 21 days. Haematoxylin-Eosin stained lung sections taken 6 d.p.i from (c) CR6261 or (d) control mAb treated mice (1 d.p.i.) and challenged with 25 LD₅₀ A/Hong Kong/156/97. (e) Survival (upper panel), mean±s.e.m. body weight, (middle panel) and median clinical signs (bottom panel) of mice (n = 10) challenged as in (c,d) and injected i.v. with 15 mg/kg CR6261 IgG1 3 (dark blue), 4 (light blue), 5 (green) or 6 days (orange) or control mAb (black dotted line) 4 days after challenge (see colored arrows in bottom panel). The day five time point at which therapeutic efficacy is lost is indicated by a grey box.