Another likelihood is that our own Stx prep contained damaging lipopolysaccharide that might begin TLR4 signaling in charge tissue, and not in TLR4-depleted tissue. Even so, using a pair of delicate lipopolysaccharide diagnosis assays, a Limulus amebocyte lysate analysis (QCL-1000, Lonza) with an NF��B news reporter assay throughout HEK293 cells revealing human TLR4, MD2, and CD14 (Yang et ing., T