Activated NK cells reprogram regulatory dendritic cells into mature dendritic-like cells.

NICOLAS IGNACIO TORRES; XIMENA RAFFO IRAOLAGOITIA; ANDREA ZIBLAT; RAUL GERMÁN SPALLANZANI; CAROLINA INES DOMAICA; MERCEDES BEATRIZ FUERTES; NORBERTO WALTER ZWIRNER

Congreso; 62 Reunión anual de la Sociedad Argentina de Imunología; 2014

Reciprocal crosstalk between dendritic cells (DC) and NK cells plays an essential role during the immune responses against tumors. In addition, tumors promote the recruitment of regulatory dendritic cells (regDC), which contributes to immune escape. regDC also have been involved in the maintenance of immune tolerance. Previously, we demonstrated that regDC restrain NK cell activation through an NKp46-mediated regulatory mechanism. However, the consequences of the crosstalk between regDC and activated NK cells remain unknown. Thus, the aim of this work was to explore the outcome of such crosstalk using murine NK cells stimulated with agonists TLRs and IL-12. We obtained immature DC (iDC) from bone marrow cells differentiated for 6 days with GM-CSF. To obtain mature DC (mDC) and regDC, iDC were stimulated overnight with 25ng/ml of LPS (mDC) or 25ng/ml of LPS and 100nM of dexamethasone (regDC). We observed that regDC induced a ten-fold reduction in proliferation of allogeneic splenocytes as compared with mDC (p