Whole blood endotoxin responsiveness in patients with chronic heart failure: the importance of serum lipoproteins.

Background Endotoxin [lipopolysaccharide (LPS)] may be an important stimulus for cytokine release in patients with chronic heart failure (CHF). We sought to investigate the relationship between whole blood endotoxin responsiveness and serum lipoprotein concentrations. It is not known if low-dose LPS is sufficient to stimulate immune activation. Methods and results Whole blood from 32 CHF patients (mean age 66±2 years, NYHA class 2.7±0.2, five female) and 11 healthy control subjects (mean age 47±4 years, six female) was stimulated with LPS at nine different concentrations (0.001 to 10 ng/mL), and tumor necrosis factor (TNF-α) release was quantified. Reference standard endotoxin at concentrat…