Citral modulates human monocyte responses to Staphylococcus aureus infection

Area of Science:

• Immunology
• Microbiology
• Pharmacology

Background:

• Staphylococcus aureus (S. aureus) is a significant human pathogen.
• Inflammatory responses drive the severity of S. aureus infections.
• Antibiotic resistance in S. aureus necessitates alternative therapeutic strategies.

Purpose of the Study:

• To investigate the immunomodulatory effects of citral on S. aureus-induced inflammation.
• To evaluate citral's impact on immune cell surface markers and cytokine profiles.
• To explore citral as a potential anti-inflammatory agent against S. aureus infections.

Main Methods:

• Human peripheral blood mononuclear cells were isolated and treated with varying concentrations of citral (4%, 2%, 1%).
• Cells were subsequently inoculated with S. aureus and analyzed for immunophenotyping (CD14, CD54, CD80, etc.) and cytokine levels (IL-1β, IL-6, IL-10, TNF-α, etc.).
• Gene expression analysis of 84 immune response-related genes was performed, with statistical analysis using GraphPad Prism.

Main Results:

• Citral modulated monocyte surface markers (CD14, CD54, CD80), indicating effects on recognition, presentation, and migration.
• Citral demonstrated inhibitory effects on key inflammatory pathways (NF-κB, JNK/p38, IFN), reducing pro-inflammatory cytokine expression (IL-1β, IL-6, IL-12p70, IL-23, IFN-γ, TNF-α).
• Levels of anti-inflammatory cytokines, such as IL-10, were increased following citral treatment.

Conclusions:

• Citral exhibits significant anti-inflammatory properties against S. aureus infections.
• Citral modulates immune cell responses and cytokine production, offering a potential therapeutic avenue.
• This study addresses a gap in the literature by correlating citral, S. aureus, and specific immune markers.