Lipoteichoic acid fractions from pathogenic and apathogenic Listeria species and Staphylococcus aureus induce similar amounts of macrophage-derived cytokines.

Lipoteichoic acids (LTAs) of pathogenic and apathogenic Listeria species and of Staphylococcus aureus were fractionated and tested for their ability to stimulate production of cytokines (IL-1alpha, IL-6, TNF-alpha) in resident peritoneal macrophages (Mvarphi) of endotoxin-resistant C3H/HeJ mice using a serum-free medium. For IL-1alpha and IL-6 there were no detectable differences in the ability of LTA fractions of pathogenic and apathogenic Listeria species and of Staphylococcus aureus. However, LTA-2 fractions of Staphylococcus aureus, which might be less hydrophobic than the LTA-2 fractions of the listeriae-induced lower amounts of TNF-alpha. Furthermore, the more lipophilic LTA-2 fractions of all LTAs employed were more potent inducers of cytokines than the less lipophilic LTA-1 fractions. The biologic effect of LTAs appears, therefore, to depend mainly on their hydrophobicity.