Human antibody‐secreting cells enriched by free flow electrophoresis

Mononuclear leukocytes of the human peripheral blood were separated by counter‐current centrifugal elutriation. In this way a group of lymphocytes was isolated, which contained B‐lymphocytes with an electrophoretic mobility (EM) of 0.9 × 10−4 (cm2 V−1 s−1) and T‐lymphocytes with an EM of 1.1 × 10−4 (cm2 V−1 s−1). This group of lymphocytes was incubated for 7 days in the presence of monocytes and pokeweed mitogen. Then the culture supernatants were screened. Non‐specific human antibodies were found in all culture supernatants. In 20% of the supernatants human antibodies against sheep red blood cells could be detected. The viable cells of the cultures were separated into 5 fractions by free flow electrophoresis. Then the cells of the different fractions were tested for their capability to produce antibodies. The tests revealed that antibody‐secreting cells had an EM around 0.9 × 10−4 (cm2 V−1 s−1) and that the greater part of the cells, isolated from pokeweed mitogen cultures, had a significant higher EM. Thus free flow electrophoresis could be applied to enrich antibody‐secreting cells ninefold.