Hence we first transiently overexpressed Flag-tagged PI15 in 293T cells (Figure S1D) for 24 h and then infected these cells with Chlamydia. Similarly, as previously observed for PI15 silencing, PI15 overexpression did not affect chlamydial primary infection, as chlamydial Hsp60 (cHsp60) protein levels remained unchanged (Figure S1D). Here, PI15 is linked to infection.