PHLPP1 and escherichia coli infection: Since macrophages are a key cell type involved in the initial response to E. coli infection and LPS challenge, we analyzed the transcriptome of BMDMs isolated from WT or Phlpp1-/- mice before and after stimulation by the major LPS component, Kdo2-Lipid A (KLA), for 1, 6, or 24 hr (Figure 2A).