Composition of the packaging reaction.

aFinal concentration of the reagents in the reaction mixture at each step is shown in parentheses.
bAverage±S.E. The titer is shown as luciferase transduction units. The number in parenthesis represents the number of repeated experiments.

a 反应体系各步骤的试剂终浓度以括号标注。
b 实验结果以平均值±标准误（Standard Error, S.E.）表示；滴度以萤光素酶转导单位（luciferase transduction units）为单位进行统计，括号内数字代表重复实验的次数。