Serum concentrations of lipopolysaccharide activity-modulating proteins during tuberculosis

Lipopolysaccharide (LPS) is the principal stimulator of host defense agains t gram-negative bacteria. LPS-binding protein (LBP), bactericidal/permeabil ity-increasing protein (BPI), and soluble CD14 (sCD14) bind LPS and regulat e its toxicity. Lipoarabinomannan, a cell wall component of Mycobacterium t uberculosis, resembles LPS with respect to induction of inflammatory respon ses through recognition by LBP and sCD14, LBP, BPI, and sCD14 were measured in serum of 124 patients with tuberculosis in various stages of disease, i n persons who had been in close contact with patients with contagious pulmo nary tuberculosis, and in healthy controls. Levels of these LPS toxicity-re gulating proteins were elevated in patients with active tuberculosis compar ed with those in contacts and controls and declined during treatment. The l evels of LBP and sCD14 were higher in patients with fever and anorexia, LPS -regulating proteins may play a role in host defense during tuberculosis, p resumably through interaction with lipoarabinomannan.