CD40LG and AIDS: Plasma levels of immunoglobulin-M (IgM) antibodies to the LPS core oligosaccharide (EndoCAb), which are normally present in human plasma and potently inhibit LPS activity [41], were significantly decreased in AIDS patients, consistent with the study by Brenchley et al. [3], probably a consequence of altered B cell function in HIV-infected individuals [42], [43].