Development of Heterotypic Combinations of Dissociated Embryonic Chick Cells.

The behavior in vitro of dissociated and reaggregated mesonephric and limb-bud cells of the early chick embryo was studied in heterotypic, isochronic and heterochronic combinations, 2. Under the conditions examined, all cell types incorporated in the cell suspensions reappeared eventually in the aggregates to form tissue-like groupings that developed in accordance with their tissues of origin. 3. Manifestation of the characteristic histogenetic activity by cells of a given type in a heterotypic combination decreased in proportion to their share in the total population. If present below a certain liminal proportion, the cells did not reconstitute their typical tissue fabric, although equal amounts, when cultured separately, would differentiate histotypically.