In myeloid dendritic cells (mDCs), TLR3 is expressed in the endosomal membrane and interacts with the adaptor toll/interleukin 1 receptor homology domain-containing adaptor molecule 1 (TICAM-1; TRIF). TICAM-1 signals culminate in interferon (IFN) regulatory factor (IRF) 3 activation. Co-culture of mDC pretreated with the TLR3 ligand polyI:C and natural killer (NK) cells resulted in NK cell acti...

Natural killer (NK) cells are essential components of the innate immune system and play a critical role in host immunity against cancer. Recent progress in our understanding of NK cell immunobiology has paved the way for novel NK cell-based therapeutic strategies for the treatment of cancer. In this review, we will focus on recent advances in the field of NK cell immunotherapy, including augmen...

While distinct stages of natural killer (NK) cell development have been defined, the molecular interactions that shape human NK cell maturation are poorly understood. Here we define intercellular interactions between developing NK cells and stromal cells which, through contact-dependent mechanisms, promote the generation of mature, functional human NK cells from CD34(+) precursors. We show that...

Because NK cells lack gene-recombination machinery and are thought to be relatively short-lived, it is unclear whether NK cells can mount long-term effective recall responses to reinfections by diverse pathogens. In this article, we report that FcRγ-deficient NK cells, which we recently identified and termed g(-)NK cells, possess distinct memory features directed by FcR-mediated Ab-dependent ta...

Although bone marrow (BM) is the main site of natural killer (NK)-cell development in adult mice, recent studies have identified a distinct thymic-dependent NK pathway, implicating a possible close link between NK- and T-cell development in adult hematopoiesis. To investigate whether a potential NK-/T-lineage restriction of multipotent progenitors might take place already in the BM, we tested t...

BACKGROUND The aim of this paper is to study the function of allogeneic and autologous NK cells against Dental Pulp Stem Cells (DPSCs) and Mesenchymal Stem Cells (MSCs) and to determine the function of NK cells in a three way interaction with monocytes and stem cells. METHODOLOGY/PRINCIPAL FINDINGS We demonstrate here that freshly isolated untreated or IL-2 treated NK cells are potent inducer...

Incubation of human peripheral blood lymphocytes with bone marrow cells resulted in significant inhibition of colony formation by committed myeloid and erythroid cells. Using positively selected homogeneous natural killer (NK) cell preparations and lymphocyte subpopulations depleted of or enriched for NK cells, we definitively characterize as NK cells the cells in normal peripheral blood that a...

Expression of adenovirus E1A gene products in tumor cells enhances NK cell lysis in vitro and NK-mediated rejection in vivo, despite increasing class I molecules on tumor cells. It is unclear why the increased expression of MHC class I molecules does not appear to confer resistance to killing by NK cells. One possibility is the unique capacity of E1A to sensitize cells to multiple NK cell killi...

Murine natural killer (NK) cells have been shown to inhibit the growth of the yeastlike organism Cryptococcus neoformans both in vivo and in vitro. An essential first step in NK cell-mediated damage of cryptococcal cells is the binding of the NK cell to the cryptococcal cell. The studies presented here focused on the binding event. Electron photomicrographs and three-dimensional reconstructions...

Natural killer (NK) cells play an important role in immune surveillance against a variety of infectious microorganisms and tumors. Limited availability of NK cells and ability to expand in vitro has restricted development of NK cell immunotherapy. Here we describe a method to efficiently expand vast quantities of functional NK cells ex vivo using K562 cells expressing membrane-bound IL21, as an...