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...

Natural killer (NK) cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through ...

aApplied Microbiology Research Center, Nippon Kayaku Co., Ltd., 225-1, Koshikiya, Horigome, Ageo-shi, Saitama 362, Japan bResearch and Development Division, Pharmaceutical Group, Nippon Kayaku Co., Ltd., 3-31-12 Shimo, Kita-ku, Tokyo 115, Japan cGraduate School of Science and Engineering, Advanced Research Institute for Science and Engineering, Waseda University, Ohkubo, Shinjuku, Tokyo 169, Japan

Recently, it has become apparent that surface proteins commonly transfer between immune cells in contact. Inhibitory receptors and ligands exchange between cells during NK cell surveillance and we report here that NK cells also acquire activating ligands from target cells. Specifically, the stress-inducible activating ligand for NKG2D, MHC class I-related chain A (MICA), transferred to NK cells...

Background: Natural killer (NK) cells originate from the differentiation of hematopoietic stem (HSCs) in common lymphoid progenitor pathway, and HSCs can be obtained umbilical cord blood (UCB). Comparative studies NK cell between cultured freshly isolated are important development therapy for cancer. This study aimed to compare maturation stages newly HSC samples using interleukin-2 absence fee...

The ability of natural killer (NK) cells to provide protection against myeloid leukemia has been demonstrated in clinical settings. However, whether NK cells play a role in the clinical course of solid tumors is debated. The controversy surrounding the role of NK cells is due, at least in part, to the limited extent of NK cell infiltration found in the tumor bed. Inactivation of NK cells may ex...

NK cells are a major component of the antitumor immune response and are involved in controlling tumor progression and metastases in animal models. Here, we show that dysfunction of these cells accompanies human breast tumor progression. We characterized human peripheral blood NK (p-NK) cells and malignant mammary tumor-infiltrating NK (Ti-NK) cells from patients with noninvasive and invasive br...

BACKGROUND Natural killer (NK) cells constantly survey surrounding tissues and remove newly generated cancer cells, independent of cancer antigen recognition. Although there have been a number of attempts to apply NK cells for cancer therapy, clinical application has been somewhat limited because of the difficulty in preparing a sufficient number of NK cells. Therefore, ex vivo NK cell expansio...