NOD1 and Klebsiella Infections: Several deubiquitinases, such as ubiquitin-specific peptidase 38 (USP38), deubiquitinase (DUB) BAP1, affect the protein stability of KLF5 through deubiquitination.59,60 A previous study reported that NOD1 controlled the expression of deubiquitinase CYLD in response to Klebsiella infection and that NOD1 knockdown abolished the upregulation of CYLD expression.61 Therefore, we supposed that the P. gingivalis-mediated stabilization of KLF5 expression might be dependent on NOD1 activation, which will be explored in our follow-up study.