Cell Report

Name	Killer Cells, Natural
Description	Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.
No. of Studies (Positive/Negative)	16(15/1)

Name in Literature	Reference	Research Type	Statistical Result	Relation Description
natural killer	Irwin, 1991	patients and normal controls	P-value-value<0.001	NK activity was significantly (P less than 0.001) lower in t...... NK activity was significantly (P less than 0.001) lower in the depressed patients than in their controls More...
natural killer (NK) cell	Caldwell, 1991	patients and normal controls	P-value-value<0.01	NK activity was significantly (p less than 0.01) lower in de...... NK activity was significantly (p less than 0.01) lower in depressed inpatients than control subjects. However, in the hospitalized schizophrenic patients values of natural cytotoxicity did not differ from controls. More...
Natural killer cell	Irwin, 1990	patients and normal controls		Both major depressive disorder and the presence of threateni...... Both major depressive disorder and the presence of threatening life events in control subjects are independently associated with a 50% reduction of natural killer (NK) cytotoxicity. More...
Natural killer cell	Irwin, 1990	patients and normal controls		Natural killer cell activity was significantly lower in both...... Natural killer cell activity was significantly lower in both depressed (n = 18) and alcoholic (n = 19) patients compared with control subjects (n = 50) More...
natural killer	Schleifer, 1996	patients and normal controls		Young adult subjects with major depression had more circulat...... Young adult subjects with major depression had more circulating leukocytes and granulocytes, fewer CD56+ (natural killer [NK]) cells, and, when the number of circulating NK cells was controlled, less NK cell activity. More...
natural killer (NK) cell	Ravindran, 1996	patients and normal controls		It has been observed that levels of circulating natural kill...... It has been observed that levels of circulating natural killer (NK) cells were elevated in depressed patients. Given that mild stressors may increase circulating NK cells, it is conceivable that the elevated NK cells in depression may be secondary to the increased stress perception associated with the illness. More...
Natural killer cell	Miller, 1999	patients and normal controls		Natural killer cell activity was reduced among older depress...... Natural killer cell activity was reduced among older depressed subjects but enhanced among younger depressed subjects More...
NK(natural killer) cell	Frank, 2002	patients only		Major depressive disorder (MDD) has been associated with al...... Major depressive disorder (MDD) has been associated with altered immunologic parameters including reductions in natural killer cell activity (NKCA). We propose that immunologic alterations, characterized by a suppression of NKCA and NK cell number concomitant with proinflammatory processes, may constitute an immunologic phenotype unique to early-age-onset depression and may be salient factors in the pathogenesis of depression. More...
NK(natural killer) cell	Antonijevic, 2003	patients and normal controls		Sleep alterations typically associated with depression, name...... Sleep alterations typically associated with depression, namely a reduction in sleep continuity and slow wave sleep (SWS) and an increase in REM density, were prominent in post- but not in premenopausal patients. More...
NK-cell	Jozuka, 2003	patients and normal controls		Compared with controls, NK-cell activity and levels of corti...... Compared with controls, NK-cell activity and levels of cortisol and DHEA were reduced in patients with major depression, whereas IL-2 levels were increased. More...
natural killer cell	Irwin, 2003	patients and normal controls		depressed patients showed declines of natural killer cell ac...... depressed patients showed declines of natural killer cell activity More...
NK	Pike, 2006	patients and normal controls	P-value-value=0.05	As compared to controls, patients with major depressive diso...... As compared to controls, patients with major depressive disorder showed lower NK activity (p = .05) and higher circulating levels of IL-6 (p < .05). More...
NK	Pavon, 2006	patients and normal controls		The MDD subjects showed higher levels of cortisol and TNF-al...... The MDD subjects showed higher levels of cortisol and TNF-alpha, increased CD3+CD8+ and NK percentages, diminished B cell counts More...

Name in Literature	Related Components
	Level	Approved Name(Name in Literature)	Type	Reference	Research Type	Statistical Result	Relation Description	All
natural killer		Pro-neuropeptide Y(neuropeptide Y)	protein	Irwin, 1991	patients and normal controls	r = -0.31, P-value < 0.001	Circulating concentrations of neuropeptide Y, but not catech...... Circulating concentrations of neuropeptide Y, but not catecholamines, were inversely correlated (r = -0.31, P less than 0.001) with NK activity More...
natural killer cell		Reactive Oxygen Species(reactive oxygen species)	molecule	Frank, 2001	patients only		Intracellular levels of monocyte ROS were significantly asso...... Intracellular levels of monocyte ROS were significantly associated with reductions in NKCA in outpatients (n = 15) diagnosed with MDD. More...
NK(natural killer) cell		Low energy(psychomotor retardation)	symptoms	Frank, 2002	patients only		Consistent with previous studies, sleep disturbance and psyc...... Consistent with previous studies, sleep disturbance and psychomotor retardation possessed significant explanatory power for variance in NK cell number and NKCA(natural killer cell activity), respectively. More...
NK(natural killer) cell		Sleep disturbances(sleep disturbance)	symptoms	Frank, 2002	patients only		Consistent with previous studies, sleep disturbance and psyc...... Consistent with previous studies, sleep disturbance and psychomotor retardation possessed significant explanatory power for variance in NK cell number and NKCA(natural killer cell activity), respectively. More...
Natural killer cell		Life events(threatening life events)	environment	Irwin, 1990	patients and normal controls		Both major depressive disorder and the presence of threateni...... Both major depressive disorder and the presence of threatening life events in control subjects are independently associated with a 50% reduction of natural killer (NK) cytotoxicity. More...
natural killer (NK) cell		Stress(stress)	environment	Ravindran, 1996	patients and normal controls		In the present investigation a laboratory stressor, comprisi...... In the present investigation a laboratory stressor, comprising a mathematical challenge, increased circulating NK cells. More...
Natural killer (NK) cell		Stress(stress)	environment	Pace, 2006	patients and normal controls		Natural killer (NK) cell percentages also increased followin...... Natural killer (NK) cell percentages also increased following stress. More...

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Genetic/Epigenetic Locus	Protein and Other Molecule	Cell and Molecular Pathway	Neural System	Cognition and Behavior	Symptoms and Signs	Environment	MDD

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Name in Literature	Reference	Research Type	Statistical Result	Relation Description
NK cell	Farid Hosseini R, 2007	patients and nomal controls		We found no significant differences in plasma concentration ...... We found no significant differences in plasma concentration of IL-4, IL-10, TNF-alpha, IFN-gamma, and immunoglobulins as well as total number of NK cells, B cells, and T cells between major depressed patients and healthy control subjects. More...