Published online by Cambridge University Press: 18 September 2015
Recently, some investigators have reported blunted natural killer cell activity (NKCA) in patients with major depression. In addition, there were some reports on negative relationships between NKCA and the occurence of negative life events. In order to replicate the above findings, the present study investigates NKCA and negative life events in 11 normal and 35 unipolar (minor, simple major, melancholic) depressed subjects. NKCA has been determined by all subjects. They completed the Questionnaire on Recently Experienced Events with scores on number and impact factor of events related to a) illness, b) working conditions, c) social relationships, d) housing problems, e) loss of possession. Depressed subjects reported higher scores on number and/or impact factor of events related to illness, social relationships and housing problems. In our investigation NKCA was significantly blunted in depressed subjects and, particularly in melancholies. So NKCA is negative correlated to the severity of depression. We were unable to detect any significant relationship between NKCA, and life events ( number of impact factors ), Our results do not corroborate the thesis that life events may affect immune function, as assessed by NKCA.