Novel Non-cellular Adhesion and Tissue Grafting in the Mutable Collagenous Tissue of the Sea Cucumber Parastichopus Parvimensis

Previous work on wound healing in holothurians (sea cucumbers) has been concerned with the relatively longterm cellular processes of wound closure and regeneration of new tissue. In this report, we characterize a short-term adhesion that is a very early step in holothurian wound healing. Dissected pieces of dermis from the sea cucumber Parastichopus parvimensis adhered to each other after only 2 h of contact, whether the cells in the tissues were intact or had been lysed. Lapshear tests showed that the breaking stresses of adhered tissues reached approximately 0.5 kPa after 24 h of contact. Furthermore, dermal allografts were incorporated into the live recipient individuals without any external pressures, sutures or artificial gels to keep them in place. Dislodging the grafts after 24 h of contact required shear stresses of approximately 14 kPa. It appears that the adhesive property of the dermis plays a key role in the initiation of this grafting.