Growth Characteristics Of Large Granular Lymphocytes In Vitro Upon Stimulation With Mitogens Phytohemagglutinin And Recombinant Interleukin-2

Abstract

A pilot experiment was performed in which peripheral blood lymphocytes were isolated from whole blood using the Ficoll-Hypaque technique. Percoll discontinuous-gradient centrifugation of peripheral blood mononuclear cells resulted in a 2-fold increase in natural killer cell activity coupled with a 3 to 4-fold increase in large granular lymphocytes. Morphology, function (NK activity), and phenotype of Percoll fractions 2-4, presumably large granular lymphocytes, were compared with that of lower density fractions 6-7 over a 28-day period. Augmentation agents phytohemagglutinin and recombinant interleukin-2 were added to the culture medium. Optimal increase in cell number of fractions 2-4 was achieved by the addition of augmentation agents phytohemagglutinin and recombinant interleukin-2 to culture medium, however, interleukin-2 alone failed to induce mitogenesis. Fractions 6-7, containing monocytes, were unstimulated.