“…Numerous virulence factors of S. marcescens , including biofilm formation, motility, prodigiosin, protease, lipase and hemolysin, are associated with QS [ 11 , 35 ]. Protease in S. marcescens can degrade immunoglobulins A and G in the host, promoting bacterial invasion and inhibiting host defense [ 36 , 37 ]. The cytotoxicity of hemolysin damages host cells through inflammation and hinders neutrophils defensive function [ 38 ].…”