Human large granular lymphocytes and natural killing: Ultrastructural studies of strontium-induced degranulation

摘要: Large granular lymphocytes (LGL) are a subpopulation of human peripheral blood mononuclear cells believed to contain the mediators spontaneous cytotoxicity or natural killing. In present study, were enriched for LGL by differential density centrifugation on Percoll gradients and examined transmission electron microscopy. The ultrastructure their binding interaction with killer-susceptible target (K562) is described in detail. Some morphological similarity between myelocytic origin was observed. Studies reported elsewhere have shown that Sr2+, an alkaline earth ion known degranulate granulocytes, inhibits NK cell function. Comparison morphology control Sr2+-treated showed Sr2+ caused several characteristic changes and, indeed, led degranulation. recovery killer function seen following vitro culture effector accompanied reappearance typical intracytoplasmic granules. These data strongly suggest granules required perhaps, involved killer-mediated cytolysis.