Cytotoxic T lymphocytes and natural killer (NK) cells represent two major types of immune cytotoxic cells that have a crucial role in innate immunity. Urban air pollution represents a common and difficult problem in the majority of metropolises, which contain high levels of traffic congestion generating great amounts of genotoxic substances. Diesel exhaust particles act as adjuvant in the immun...

Background: Although there is convincing data in support of the effectiveness of hyperthermia in tumor therapy, the molecular mechanisms underlying the clinical effects of hyperthermia are still poorly understood. Objective: To investigate natural killer (NK) cell cytotoxicity against heat-treated SW-872 and HeLa tumor cell lines. Methods: NKG2D ligands and HLA class I transcription were examin...

Altered sialic acid processing that leads to upregulation of cell surface sialylation is recognized as a key change in malignant tissue glycosylation. This cancer-associated hypersialylation directly impacts the signaling interactions between tumor cells and their surrounding microenvironment, especially the interactions mediated by immune cell surface sialic acid-binding immunoglobulin-like le...

Human NK cells adhere to and lyse porcine endothelial cells (pEC) and therefore may contribute to the cell-mediated rejection of vascularized pig-to-human xenografts. Since MHC class I molecules inhibit the cytotoxic activity of NK cells, the expression of HLA genes in pEC has been proposed as a potential solution to overcome NK cell-mediated xenogeneic cytotoxicity. HLA-G, a minimally polymorp...

alpha-Galactosylceramide (alphaGalCer) stimulates NKT cells and has antitumor activity in mice. Murine NKT cells may directly kill tumor cells and induce NK cell cytotoxicity, but the mechanisms are not well defined. Newly developed human CD1d/alphaGalCer tetrameric complexes were used to obtain highly purified human alphaGalCer-reactive NKT cell lines (>99%), and the mechanisms of NKT cell cyt...

Although real-time cell electronic sensing (RT-CES) system-based natural killer (NK) cytotoxicity has been introduced, it has not been evaluated using human blood samples. In present study, we measured flowcytometry based assay (FCA) and RT-CES based NK cytotoxicity and analyzed degranulation activity (CD107a) and cytokine production. In 98 healthy individuals, FCA with peripheral blood mononuc...

Natural killer (NK) cells have been known to enhance the host immune responses against cancer. NK cell number and cytotoxicity in patients with cancer is often low. Therefore, we developed a large-scale ex vivo NK cell expansion method without feeder layers and introduced NK cell-based autologous immune enhancement therapy (AIET). In this paper, we discuss the epidemiological data that show the...

AIMS Allogeneic human cardiac-derived stem/progenitor cells (hCPC) are promising candidates for cardiac repair. They interact with T cells, major effectors of the adaptive immune response, inducing 'paracrine' anti-inflammatory effects that could sustain tissue repair/regeneration. Natural killer (NK) cells are major effectors of the innate immune system that might influence the persistence of ...

Non-major histocompatibility complex-restricted cytotoxicity or natural killer (NK) activity could be detected in all intestinal lamina propria mononuclear cell preparations of histologically normal mucosa from 57 patients with gastrointestinal disease. Similar levels of NK activity were detected among the different disease groups. Within the inflammatory bowel disease patient group, however, C...

Natural killer (NK) cells play an important role in anti-tumor immunity. Interleukin (IL)-18 is an immunoregulatory cytokine that induces potent NK cell-dependent anti-tumor responses when administrated with other cytokines. In this study, we explored the effects of combining IL-18 and IL-2 on NK cytotoxicity as well as expression levels of the NK cell receptor NKG2D in vitro. Freshly isolated ...