[Deficiency of NK activity evolving in a parallel manner with immune granulopenia]

The role of NK cells and their place in blood lines remain the subject of controversy. The authors report on a 42-year-old patient who exhibited a regressive auto-immune granulopenia following administration of anti-lymphocytic serum and also during immunosuppression by cyclophosphamide after a relapse. The NK activity level closely paralleled the evolution of the granulopenia. The possible relationships between these two phenomena are discussed, and the possible role of membrane antigens common to NK cells and myeloid lines.