Dendritic Cells: Elegant Arbiters in Human Reproduction

The female reproductive tract represents a great challenge to the residing immune cells: Concomitantly, those immune-competent cells have to provide tolerogenic mechanisms favoring the development of a successful pregnancy while permitting protection against harmful pathogens. The predominant cell population facing this “double edged” regulatory capacity within the reproductive tract is that of dendritic cells (DC). There is evidence that DC represent a highly adaptive cell type, which can either be transformed in an immune-stimulatory phenotype after exposure to inflammatory or infectious signals, or in an immune inhibitory phenotype preventing T cell activation when located in an adequate antiinflammatory microenvironment. Thus, this review highlights this two-faced character of DC focusing on their morphology and function within the human reproductive tract and especially during pregnancy.