Dendritic Cells: More Than Just Adaptive Immunity Inducers?

Dendritic cells (DC) are well known for their capacity to induce immune responses and there is also accumulating evidence of their ability to interact with various cell types of the innate system, such as NK, NKT or TCRγδ cells. These interactions are bi-directional, mediated by soluble or cell surface molecules and have been mainly described in the context of immune responses to infectious agents and tumors. NK, NKT or TCRγδ cells induce the maturation of DC, as shown by the increased expression of CD86, IL12 production and priming of T cell responses. On the other hand, mature DC have the ability to activate NK, NKT or TCRγδ cells for sustained innate immune responses and activated NK cells may kill immature DC. In addition, DC and NK or TCRγδ cells share similar functions such as cytotoxic and antitumor activity, interferon production and antigen presentation capacity.