Annexins I and IV inhibit Staphylococcus aureus attachment to human macrophages

The present study investigated the effect of annexins on interaction between Gram-positive bacteria and immune cells such as macrophages. Annexins I and IV bound to lipoteichoic acids which are surface molecules on Gram-positive bacteria. Binding of annexins I and IV to whole Staphylococcus aureus (S. aureus) were observed and these bindings were inhibited by lipoteichoic acid from S. aureus. Moreover, annexins I and IV suppressed the attachment of S. aureus to phorbol 12-myristate 13-acetate-treated THP-1 cells (human macrophages). These results suggest that annexins I and IV have ligand specificities toward foreign substances, and that the annexins might have some anti-inflammatory property for Gram-positive bacteria.