[Mannan-Binding Lectin Inhibits Candida Albicans-Induced DC Maturation and Cytokine Secretion]

Area of Science:

• Immunology
• Cell Biology

Background:

• Dendritic cells (DCs) are crucial in initiating immune responses.
• Candida albicans (C. albicans) is a fungal pathogen that can trigger immune responses via DCs.
• Mannan-binding lectin (MBL) is a key component of the innate immune system involved in pathogen recognition.

Purpose of the Study:

• To investigate the impact of MBL on the maturation and cytokine secretion of human dendritic cells (DCs) stimulated by C. albicans.
• To elucidate the molecular mechanisms underlying MBL's effects on DCs during C. albicans infection.

Main Methods:

• Human peripheral blood mononuclear cells were differentiated into monocyte-derived dendritic cells (MoDCs).
• MoDCs were stimulated with C. albicans in the presence of varying MBL concentrations.
• DC maturation markers (CD83, CD86), cytokine levels (TNF-α, IL-6), MBL-DC/C. albicans interaction, IκBα phosphorylation, and p65/NF-κB translocation were analyzed using FACS, ELISA, and Western blot.

Main Results:

• MBL, particularly at higher concentrations (10-20 mg/L), down-regulated CD83 and CD86 expression on C. albicans-stimulated MoDCs.
• MBL inhibited the production of TNF-α and IL-6 induced by C. albicans.
• MBL demonstrated binding to both C. albicans and immature DCs in a Ca2+-dependent manner, and it reduced IκBα phosphorylation and p65/NF-κB nuclear translocation.

Conclusions:

• MBL inhibits C. albicans-induced TNF-α and IL-6 production in DCs, likely via the NF-κB signaling pathway.
• MBL plays a regulatory role in the immune response to C. albicans infections.