Deficiency of monoclonal antibody-defined NK Cells (HNK-1+) in primary immunodeficiency disorders.

Natural killer (NK) cells were enumerated in the peripheral blood mononuclears from 13 patients with primary immunodeficiency disease, using recently developed monoclonal antibody, Leu 7 (HNK-1). Eight of 13 patients demonstrated quantitative deficiency of NK cells when compared to simultaneously studied healthy controls, using monoclonal antibody and fluorescence-activated cell sorter (FACS). The quantitative deficiency of NK cells could be one of several factors responsible for increased susceptibility to infections and increased incidence of malignancies in patients with primary immunodeficiencies.