Continuous formation of plasma cells in long-term cultures of spleen

Abstract

Splenic tissue of different species were grown in vitro to provide long-term cultures for immunologic and morphologic studies. A regular growth, with the continuous differentiation of mature types of cells, was obtained. Reticular cells, transitional cells, and mature plasma cells of the Marschalko type were identified by observing these cultures by phase-contrast microscopy and as fixed preparations stained with Giemsa or methyl-green-pyronin. A similar differentiation, with peculiar species characteristics, was obtained in splenic cultures of chicken, mouse, rat, rabbit, and man. They were easily subcultured and grown for various periods of time, up to 14 months at the time of report. Embryo-spleen cultures also form mature plasma cells although, according to general knowledge, plasma cells are not found in animals before birth. Long-term splenic cultures with continuous differentiation of plasma cells provide an opportunity to study the long-debated origin of these cells, as well as a system suitable for immunologic investigation in vitro.