Decreased cell mediated cytotoxicity occurs frequently in inflammatory bowel disease, particularly in patients with active disease. It is not clear, however, whether this decrease is caused by the disease or is a consequence of the medical treatment. In this study we evaluated the effect of in vivo treatment with 5-aminosalicylic acid and sulphasalazine on the in vitro natural killer cell activ...

BACKGROUND Natural killer cells have been demonstrated to exert remarkable graft-versus-leukemia effects after haploidentical transplantation. Acquisition of both, inhibiting and activating, receptors on developing natural killer cells is an important step in their functional maturation. Here, we report on the reconstitution of natural killer receptors after haploidentical transplantation of T-...

Natural killer (NK) cells play a crucial role in regulating immune functions. Few studies have characterized canine NK cells. We previously demonstrated that canine peripheral blood lymphocytes (PBLs) with a low surface CD5 density (CD5lo) are considered a critical NK population. Natural killer cells in most mammals do not express T-cell markers, but canine CD5lo cells express surface molecules...

The administration of epinephrine to humans increases natural killer (NK) cell activity and numbers. If endogenous catecholamines regulate NK cells, then their activity should be increased by cocaine, an agent that potentiates endogenous catecholamines. We investigated the in vivo effect of cocaine on NK cell activity and on the distribution of lymphocyte subsets, including NK cells. Intravenou...

Natural killer (NK) cells are a heterogenous subpopulation of peripheral blood lymphocytes (PBL) that have the ability to kill various tumors and tumor cell lines in the absence of prior sensitization. These cells have generated considerable interest and have been implicated in natural resistance to tumors,'-5 resistance to viral infection:-7 transplantation rejection,'** and immunoregulation o...