Multicellular spheroid formation and evolutionary conserved behaviors of apple snail hemocytes in culture

► A culture system for Pomacea canaliculata's hemocytes was developed. ► Hemocyte spreading and phagocytosis were observed in short-term cultures. ► Large spheroidal aggregates were formed in longer cultures (>4 h). ► Later, spheroidal aggregates increased in size and merged with adjacent spheroids. ► Aggregates may be significant in snail immunity and other fields of cell biology.