ABSTRACT
Natural resistance was manifested by lower incidence and reduced growth rate of parental leukemia-lymphoma tumors after transplantation into F1 hybrid recipients in comparison to the optimal growth of the same tumors upon transplantation into syngeneic mice. In contrast to the multitude of investigations on Natural killer (NK) cell cytotoxicity in patients with solid cancers, studies of the NK cell cytotoxic profile in patients with leukemia are relatively infrequent. The studies on the characterization of peripheral blood effector cells displaying impaired cytotoxic potential are sporadic and to some degree controversial. Most of the peripheral blood NK cell activity has been shown to be associated with a subpopulation of lymphoid cells designated large granular lymphocytes, characterized morphologically by a reniform nucleus, a low nucleus to cytoplasm ratio, and cytoplasmic azurophilic granules. Patients with myeloid and lymphoid leukemia exhibited low levels of NK cell cytotoxicity in Ficoll-Hypaqued peripheral blood.
