Interestingly, MyD88 protein levels were decreased (Fig 1E and 1F), while co-localization of MyD88 with the proteasome marker PSMD2, the specific marker for 19S subunit of the proteasome [16], was enhanced significantly in K-macrophages from CFT073wt infected mice with pyelonephritis compared to K-macrophages isolated from mice infected with CFT073Δtcpc (Fig 1G–1I). Here, MYD88 is linked to pyelonephritis.