First, to validate the high-inducer phenotype, bone marrow derived (BMD) macrophage cells were infected with each of the LTA mutants, ΔmarR/lafA::Tn, ΔmarR/lafB::Tn, ΔmarR/ltaP::Tn, and real time quantitative PCR (RT-qPCR) analysis of IFN-β expression was performed at 6 h post infection (h.p.i.). This evidence concerns the gene IFNB1 and infection.