Figure 1. Vaccine recovery after lyophilization in study of protective efficacy of lyophilized vesicular stomatitis virus–based vaccines in animal model. A) VSV∆G/LASVGPC vaccine stored at 4°C; B) VSV∆G/EBOVGP vaccine stored at 4°C; C) VSV∆G/LASVGPC vaccine stored at 21°C; D) VSV∆G/EBOVGP vaccine stored at 21°C; E) VSV∆G/LASVGPC vaccine stored at 21°C; F) VSV∆G/EBOVGP vaccine stored at 21°C. VSV∆G/LASVGPC or VSV∆G/EBOVGP vaccines were lyophilized in DMEM containing no excipients or containing combinations of 5% lactalbumin hydrolysate, 10% sucrose, 5% trehalose, or 0.5% gelatin and stored at different temperatures. At the specified time points, vaccines were resuspended in triplicate in normal saline, titered by using standard tissue culture techniques, and the median TCID₅₀ was calculated for each. p values are indicated above brackets. Errors bars are SDs. DMEM, Dulbecco modified Eagle medium; G, gelatin; LS, lactalbumin hydrolysate and sucrose; NC, not calculated; T, trehalose; TCID₅₀, 50% tissue culture infectious dose; VSV-Lassa, vesicular stomatitis virus expressing Lassa virus glycoprotein; VSV-Zebov, vesicular stomatitis virus expressing Ebola virus glycoprotein.