Reaggregation of insect cells in vitro. i. adhesive properties of dissociated fat-body cells from developing saturniid moths

TLDR: In the experiments reported here, the plienomellon has been further examined in order to identify the factors prerequisite to this mutual adhesiveness between fat-body cells.

Abstract: Cells dissociated from the fat-body of developing saturniid moths undergo rapid reaggregation when cultured in insect blood (Walters and Williams, 1966). The phenomenon as a whole is reminiscent of the self-reconstruction of tissues from the dissociated cells of sponges and vertebrate embryos (Wilson, 1907: Townes and Holtfreter, 1955 ; Humphreys, 1963 ; Moscona, 1965 ) . The important difference is that the cells of the dissociated fat-body lack any intrinsic motility or power of locomotion. By means of time-lapse cinematography, it was possible to show that the dissociated fat-body cells are drawn together by certain motile hemocytes which are regularly present in the hemolymph of developing moths. These “?�plasmato cytes” were seen to crawl about and frequently adopt a single shape with their elongate processes adhering to two or more fat-body cells or groups of cells which were then pulled together by the active contraction of the plasmatocytes. In stationary cultures of dissociated fat-body cells, reaggregation was completely blocked when the plasniatocytes were removed or otherwise inactivated. Cultures lacking all hemocytes could l)e made to reaggregate, however, by subjecting them to gentle agitation. The fat-body cells collided at random and cohered to form large aggregates. This finding strongly implies an intrinsic adhesiveness between fat-body cells. In the experiments reported here, the plienomellon has been further examined in order to identify the factors prerequisite to this mutual ad hesion.