Human NK cells are characterized by their ability to initiate an immediate and direct cytolytic response to virally infected or malignantly transformed cells. Within human peripheral blood, the more mature CD56(dim) NK cell efficiently kills malignant targets at rest, whereas the less mature CD56(bright) NK cells cannot. In this study, we show that resting CD56(bright) NK cells express signific...

Cell lines with natural killer (NK) activity grown from native spleen cells cultured in medium conditioned by spleen cells proliferating in the presence of concanavalin A (Con A) were characterized. One NK cell line was cloned and assayed on several human and mouse NK-sensitive targets to analyze whether target specificities segregate upon cloning. Results showed that NK clones display target s...

NK cells are defined as those cells that lyse tumor cells without priming. In this study, we show that the preincubation of resting human NK cells with the leukemia cell CTV-1 primes NK cells to lyse NK-resistant cell lines, primary leukemias, and solid tumors even when HLA-matched, allogeneic or autologous. The primed NK cells remained nonresponsive to HLA-C matched and mismatched normal monon...

NK cells contribute to antitumor and antiviral immunosurveillance. Their development in the bone marrow (BM) requires the transcription factor E4BP4/NFIL3, but requirements in other organs are less well defined. In this study, we show that CD3(-)NK1.1(+)NKp46(+)CD122(+) NK cells of immature phenotype and expressing low eomesodermin levels are found in thymus, spleen, and liver of E4BP4-deficien...

Human natural killer (NK) cells are functionally regulated by killer cell immunoglobulin-like receptors (KIRs) and their interactions with HLA class I molecules. As KIR expression in a given NK cell is stochastically established, KIR repertoire perturbations reflect a dominance of discrete NK-cell subsets as the consequence of adaptation of the NK-cell compartment to exogenous agents, more ofte...

We characterize the natural killer (NK) cell colony-inhibiting activity (CIA) produced in supernatants from cultures of human peripheral blood lymphocytes (PBL) with NK-sensitive target cell lines, and study its relationship with NK cell-derived cytotoxic factor (NKCF). Using monoclonal antibodies (mAb) specific for NK cells or other lymphocyte populations, we unambiguously identify NK cells as...

Natural killer (NK) cells play a crucial role in the defense against tumors. Peripheral blood monocytes are routinely assayed for the activity of NK cells by using a 4hr-51Cr release assay, and subsets of the NK cells are determined with monoclonal antibodies directed against surface phenotypes of the NK cells. We reviewed associations of demographic characteristics and individual lifestyles wi...

Background Despite the ability of NK cells to kill cancer cells, NK cell–based immunotherapy has resulted in limited clinical benefit. This is largely due to the poor capacity of adoptively transferred NK cells to home to tumors. We have shown that NK cells are able to kill osteosarcoma (OS) cells in vitro in a dose-dependent manner, indicating that recruiting more NK cells to OS lung metastasi...