Natural killer (NK) cells were discovered more than 30 years ago. NK cells are large granular lymphocytes that belong to the innate immune system because unlike T or B lymphocytes of the adaptive or antigen-specific immune system, NK cells do not rearrange T-cell receptor or immunoglobulin genes from their germline configuration. During the past 2 decades there has been a substantial gain in ou...

-A line of human leukaemia-derived cells is described that kills a wide range of human and animal cell lines, whether normal or malignant, even at a ratio of 1: 1. During exposure to the target cells, the killer cells released a factor into the culture medium which destroyed target cells in the absence of the killer cells. This phenomenon occurs without exogenous complement and requires no pre-...

Natural killer cells can be divided into five subpopulations based on the relative expression of CD16 and CD56 markers. The majority of natural killer cells are CD56(dim), which are considered to be the main cytotoxic effectors. A minority of the natural killer cells are CD56(bright), and function as an important source of immune-regulatory cytokines. Shifts of these subsets have been reported ...

cytes. OK-432, a potent immunopotentiating agent widely used in Japan, has been shown to augment the cytotoxicity of various effector cells, including macrophages, natural killer cells, and killer T cells. Therefore, these two biologic response modifiers are expected to act in a synergistic manner for a tumoncidal effect. Following the immunotherapy, our patient showed an increased capacity of ...