AKT1 and infection: These results agree with previous studies suggesting that the steady-state levels of active Rac are increased in ABR (and Bcr) deficient cells.40 Following infection with EPEC-∆espH/pEspHwt, active Rac1 and Cdc42 levels in the ABR shRNA treated cells were still upregulated, albeit at somewhat reduced levels compared to the uninfected cells (Figure 5d).