Differentiation of Argyrophil and Argentaffin Cells in Organotypic Cultures of Embryonic Chick Intestine

Abstract

ABSTRACT Argyrophil, Bodian positive cells, and argentaffin, Masson-Hamperl positive cells differentiate in vitro in organotypic cultures of intestine of chick embryos explanted before argyrophil and argentaffin cells are known to differentiate, which is at the 14th and the day of incubation, respectively. During culture in vitro, argyrophil and argentaffin granules differentiate simultaneously; the number of cells demonstrable with either method does not show any significant difference throughout the duration of the cultures, which were incubated up to a maximum of 6 days. This result is at variance with what occurs in vivo, where argyrophil cells differentiate earlier than argentaffin cells and are in earlier stages 3 or 4 times as frequent as the latter, becoming only twice as numerous at a later stage. As in development in vivo, argyrophil and argentaffin cells differentiating in the intestine of the chick embryo are mainly situated in the epithelium. Only very few are found in the connective tissue of the lamina propria. Simard & van Campenhout (1932) and Ghidini (1940) showed that enterochromaffin granules differentiate in chorioallantoic grafts of intestine of chick embryos and they disproved in this way any kind of derivation of the enterochromaffin substance (enteramine) from the lumen of the gastrointestinal tract, as well as its formation under the influence of normal nervous connexions. It is now shown that the specific granules differentiate also in intestine cultivated in vitro and therefore in conditions which exclude any other possible mode of correlation with the whole organism, and particularly any uptake of enteramine from the blood, thus strongly supporting the conclusion that it is synthesized in situ.