Influence of separation techniques on the distribution and function of lymphocyte subpopulations. A comparison of three techniques.

The effect, if any, of three different lymphocyte separation techniques on the composition and functional characteristics of the purified cell suspensions has been studied. Each separation technique was shown to yield a cell population with highly specific and reproducible characteristics. The Ficoll-Hypaque technique led to good lymphocyte yields but low yields of sheep erythrocyte-rosetting (E-rosetting) T cells, and the separated cell population responded least well to phytohemagglutinin. The glass sand filtration technique led to lowest overall yield of small lymphocytes and of EAC-rosetting cells. There was significantly lower total yield of E-rosetting T cell as well, but the separated lymphocyte suspension had excellent purity, had relatively high percentage of E-rosetting T cells, and they responded extremely well to phytohemagglutinin (PHA) and pokeweed mitogen (PWM). The Technicon separation involving magneticremoval of phagocytic cells by exposure to iron particles consistently led to large yields of small lymphocytes with good purity, the largest total harvests of E-rosetting T cells, as well as EAC-rosetting cells while the separated population had the highest percentage of E-rosetting cells and responded very well to PHA and PWM. These results show that lymphocyte losses during purification are not nonspecific and that the choice of the separation technique profoundly affects the characteristics of the purified lymphocyte population obtainable.