Whilst others have shown activation of TLR2 by LPG preparations in vitro resulting in inflammatory responses [10, 16, 18], it is important to note that this is in contrast to many of the known functions of LPG in vivo, which are related to the down regulation of inflammatory responses [46–49], so it would be paradoxical for LPG to also promote protective immune responses in the context of an in vivo infection. The gene discussed is APOE; the disease is infection.