Elevated natural killer (NK) cell activity: a possible role in resistance to infection and malignancy in immunodeficient splenectomized patients.

Splenectomized patients, who have had their spleens removed following trauma, have immune deficiencies. However, the risk of infection (with one exception--septicaemia caused mainly by Streptococcus pneumoniae) and malignancy in these patients appears to be comparable to that of healthy individuals. We propose that a compensatory increase in the activity of effector cells, such as natural killer cells (NK) and macrophages, may protect against infection and malignant diseases in splenectomized individuals.