Development of reporter monocytic cell lines for early autophagy and membrane damages during S. aureus infection

Macrophages are professional phagocytes having a crucial role in innate immune response. These myeloid immune cells are able to perform phagocytosis, and they participate in pivotal processes like inflammation, wound healing and adaptive immune response. Being able to engulf and digest pathogens, macrophages have an essential role in the response against bacterial infection too. Pathogens phagocytosis involves many components of the autophagy machinery, which plays a critical role in the macrophage response to bacterial infection. Nonetheless, the autophagic response can be modulated and manipulated by several bacterial species, which are able to block their degradation and even benefit from the autophagic pathway. Engulfed pathogens can escape macrophages inducing membrane damages, through toxins production or membrane-damaging cell death induction (e.g. necroptosis). The ESCRT-III membrane repair machinery plays a crucial role in the maintenance of membranes integrity during physiological and infection relevant processes. In this work, THP-1 cells were transduced using a 3rd generation Lentiviral System, obtaining two stable monocytic cell lines usable as models for investigation of early-stage autophagy formation, as well as membrane damages and repair upon bacterial infection. In particular, these two cell lines can be a valuable tool to investigate macrophages infection by S. aureus, a major human pathogen causing concern due to its ability to escape phagocytosis and its increasing antibiotic resistance.