https://www.selleckchem.com/products/BIX-02189.html Upon L. pneumophila challenge of bone marrow-derived macrophages (BMDM) in vitro, secretion of IL-1β and TNF-α proteins was also reduced in Tβ4-Tg macrophages, without affecting their survival. The anti-inflammatory effects of BMDM in Tβ4-Tg mice on each cytokine were affected when triggering with tlr2, tlr4, tlr5, or tlr9 ligands, suggesting that anti-inflammatory effects of Tβ4 are likely mediated by the reduced activation of Toll-like receptors (TLR). Finally, Tβ4-Tg mice in a systemic sepsis model were protected from L. pneumophila-induced lethality compared to wild-type controls. Therefore, Tβ4 confers effective resistance against L. pneumophila via two pathways, a bactericidal and an anti-inflammatory pathway, which can be harnessed to treat acute pneumonia and septic conditions caused by L. pneumophila in humans.Mutation of purR was previously shown to enhance the virulence of Staphylococcus aureus in a murine sepsis model, and this cannot be fully explained by increased expression of genes within the purine biosynthesis pathway. Rather, the increased production of specific S. aureus virulence factors, including alpha toxin and the fibronectin-binding proteins, was shown to play an important role. Mutation of purR was also shown previously to result in increased abundance of SarA. Here, we demonstrate by transposon sequencing that mutation of purR in the USA300 strain LAC increases fitness in a biofilm while mutation of sarA has the opposite effect. Therefore, we assessed the impact of sarA on reported purR-associated phenotypes by characterizing isogenic purR, sarA, and sarA/purR mutants. The results confirmed that mutation of purR results in increased abundance of alpha toxin, protein A, the fibronectin-binding proteins, and SarA, decreased production of extracellular proteases, an increased capacity to form a biofilm, and increased virulence in an osteomyelitis model. Mutation of sarA had the opposite eff