Distinct modulation of chemokine expression patterns in human monocyte-derived dendritic cells by prostaglandin E₂

Dendritic cells (DCs) are key in regulating immune responses. DCs reside in tissues facing the environment and sample their surrounding for pathogens. Upon pathogen encounter, DCs mature and migrate into secondary lymphoid organs. Distinct maturation signals dictate the ability of DCs to produce distinct patterns of chemokines that orchestrate immunity. Prostaglandin E2 (PGE2) is produced during inflammation and modulates DC functions. We demonstrate that PGE2 modulates distinct chemokine expression patterns of human monocyte-derived (Mo) DCs upon maturation with various stimuli. PGE2 dampened early production of the inflammatory chemokines CCL2, CCL4, CCL5 and attenuated the expression of the T cell attractant CXCL10. In contrast, PGE2 enhanced CXCL8 production early during maturation, whereas CXCL16 levels were continuously elevated, contributing to innate immune cell recruitment. Moreover, PGE2 induces transcription of the homeostatic chemokines CCL17 and CCL22. Finally, mature MoDCs produced the homing chemokine CCL19 and its expression was down-regulated by PGE2