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

Abstract

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.

The role of the Listeria monocytogenes surfactome in biofilm formation

“…Though transposon mutant library screens indicated importance of LTA and WTA in biofilm formation process, limited validation studies have been performed in Listeria to confirm these findings. LTA structure seems to be conserved among strains and consists of a polyglycerol phosphate backbone substituted by D-alanine and galactose in L. monocytogenes (Nichterlein et al, 1997). L. monocytogenes synthesizes the LTA backbone by the enzymes LtaP (Lmo0644), a primase that produces glycerolphosphate glycolipids, and LtaS (Lmo0927), an LTA synthase that produces polyglycerolphosphate chains (Webb et al, 2009) (Fig 1C).…”

“…Though transposon mutant library screens indicated importance of LTA and WTA in biofilm formation process, limited validation studies have been performed in Listeria to confirm these findings. LTA structure seems to be conserved among strains and consists of a polyglycerol phosphate backbone substituted by D‐alanine and galactose in L. monocytogenes (Nichterlein et al ., 1997). L .…”

“…Furthermore, the structure of L. innocua LTAs has not yet been determined. Nevertheless, they exhibit similar potential to stimulate phagocytes to produce proinflammatory cytokines, implying large structural similarities with L. monocytogenes LTAs (Nichterlein et al ., 1997).…”