salmonella enterica serovar typhimurium expressing mutant lipid a with decreased endotoxicity causes maturation of murine dendritic cells a major salmonella component involved in cellular activation is the lipopolysaccharide lps molecule which can act as a dendritic cell dc stimulator the structure of the lipid a domain of the lps molecule dictates its immunostimulatory capacity with various cell types in this study the role of lipid a as an integral component of salmonella in stimulating murine dcs was studied by using a salmonella enterica serovar typhimurium lpxm mutant with defective lipid a this study revealed that a mutation in lpxm did not significantly affect the ability of bacteria to activate dcs although the lpxm mutant less tumor necrosis factor alpha interleukin1beta and inducible nitric oxide synthase than the parental strain this was only seen at lower multiplicities of infection mois both strains upregulated surface molecule expression on dcs and augmented the tcellstimulating capacity of these cells in an moiindependent manner thus the lpxm mutation did not appear to affect the stimulatory capacity of the salmonella mutant