Distinctive role of efferocytosis in dendritic cell maturation and migration in sterile or infectious conditions

Efferocytosis, or clearance of apoptotic cells (ACs), by dendritic cells (DCs) leads to immune response suppression and tolerance to self-antigens. However, efferocytosis of infected apoptotic cells (IACs) leads to the production of a mixed pro- and anti-inflammatory cytokine milieu. We examined the DC phenotype and ability to migrate after phagocytosis of ACs or IACs and observed higher levels of CD86 and CCR7 expression in DCs, as well as enhanced migration capacity following efferocytosis of IACs. Interestingly, higher levels of interleukin-1, interleukin-10 and prostaglandin E-2 (PGE(2)) were also produced in this context. Blockage of IAC recognition led to an impaired maturation profile and PGE(2) production, which may have contributed to reduced CD86 and CCR7 expression and migration capacity. These data contribute to the understanding of how efferocytosis of sterile or infected cells may regulate the adaptive immune response, although the precise role of PGE(2) in this process requires further investigation.