Rapid discovery and optimization of therapeutic antibodies against emerging infectious diseases

Rogers, J.; Schoepp, R.J.; Schröder, O.; Clements, T.L.; Holland, T.F.; Li, J.Q.; Li, J.; Lewis, L.M.; Dirmeier, R.P.; Frey, G.J.; Tan, X.; Wong, K.; Woodnutt, G.; Keller, M.; Reed, D.S.; Kimmel, B.E.; Tozer, E.C.

Retired breeder Balb/c mice were split into two groups, with one group injected i.p. with 15 mg/kg of the best optimized antibody (2978/10) and a second group injected i.p. with a similar dose of an irrelevant isotype-matched antibody. Immediately following the antibody injection, mice were challenged by aerosol exposure to SARS-CoV using a wholebody chamber within a class III biological safety cabinet maintained under negative pressure for 10 min. The aerosol was created by a three-jet collison nebulizer (BGI, Inc. Waltham, MA, USA) controlled by an automated bioaerosol exposure system (Hartings, 2004) . Aerosol concentration of virus was determined by constant sampling of the chamber using an all-glass impinger (AGI; Ace Glass, Vineland, NJ, USA) with Hank's balanced salt solution (HBSS) containing 1% fetal calf serum and 0.08% antifoam A as the collection medium. Virus concentration in starting solutions and all-glass impinger (AGI) was determined by plaque assay. Determination of presented dose was calculated using respiratory minute volume (V m ) estimates derived by Guyton's formula (V m ¼ 2.10 + W b 0.75 where W b is body weight). Presented dose was calculated by multiplying the total volume (V t ) of experimental atmosphere inhaled