Role of different sponge cell types in species specific cell aggregation.

Abstract

INVESTIGATIONS into species specific sponge cell reaggregation, aimed at illuminating the nature of the adhesive elements at the cell surface and the mechanism responsible, have apparently neglected the fact that a population of dissociated sponge cells consists of several different types which may have dissimilar adhesive properties. Yet the classical studies of reaggregation1 indicate that some cell types are markedly more active than others in forming aggregates. We have now partially separated , the different cell types by density gradient centrifugation and investigated their ability to reaggregate. It seems that the presence of archaeocytes is necessary for aggregation to take place but species specificity in the sorting out process is conferred by mucoid cells in interaction with the archaeocytes.