(A) Percent β arr2 expression over time in spleen is significantly lower in Cre positive versus Cre negative mice (*** p <0 .0001 by two-way ANOVA)(n=3 mice at each time point on days 8, 10 and n=2 at each time point day 12). (B) Percent βarr2 expression at day 12 in spleen relative to pretreatment expression levels (*** p=0.0002 by t-test)(n=2 at each time point).