Following infection of differentiated THP-1 cells with Bt at an MOI of 1, treatment with TLR4-ab–compared to an isotype control–significantly reduced supernatant TNF-α concentrations in the presence of rhLTF (p = 0.03) or phLTF (p = 0.008), but not media alone (Fig 6B). Here, TLR4 is linked to infection.