Natural killer (NK) cells are part of the innate immune defense against infection and cancer and are especially useful in combating certain viral pathogens. The utility of NK cells in human health has been underscored by a growing number of persons who are deficient in NK cells and/or their functions. This can be in the context of a broader genetically defined congenital immunodeficiency, of wh...

the  non-classical mhc  class-i mainly involves in the  regulation of  innate  immune responses where hla-e  plays a significant role in the cell identification by natural killer cells. hla-e is a main regulatory ligand for natural killer cells and given the importance of these effector cells in hematopoietic stem cell transplantation, we investigated the effect of hla-e polymorphisms on post-h...

Lymphoid neoplasms that are derived from natural killer (NK) cells are uncommon but distinct clinicopathologic disease entities. Three types have been recognized and categorized in the latest World Health Organization classification: extranodal NK cell lymphoma, nasal-type; aggressive NK cell leukemia; and blastic NK cell lymphoma. All NK tumor cells express the NK cell marker CD56, but they la...

Natural killer (NK) cells are essential for killing transformed and virally infected cells. To prevent auto-reactivity, NK cell activation is inhibited by inhibitory receptors that activate the tyrosine phosphatase SHP-1, which dephosphorylates signaling molecules crucial for NK cell activation. Initially, only a single SHP-1 substrate was identified in NK cells, the GEF VAV1. We recently demon...

hematopoietic cord blood (cb) stem cell transplantation has more advantages to other cell sources because of lower graft versus host disease (gvhd). interleukin-15(il-15) is an immunoregulatory cytokine, known to enhance cytolytic function of cord natural killer (nk) cells. the aim of this study was to investigate the effect of il-15 on nk cytotoxicity simultaneously in different cell death sta...

Natural killer cells are well known to mediate anti-leukemic responses in myeloid leukemia but their role in myelodysplastic syndromes is not well understood. Here, in a cohort of newly diagnosed patients (n=75), widespread structural and functional natural killer cell defects were identified. One subgroup of patients (13%) had a selective deficiency of peripheral natural killer cells (count <1...