Purification of a cytolytic factor from purple fluid of a sea hare

Abstract

A cytolytic factor inducing tumor lysis was purified approx. 1000‐fold from purple fluid of the sea hare Aplysia kurodai . The purified factor appeared homogeneous on polyacrylamide gel electrophoresis and consisted of a single polypeptide chain of 60 kDa. The cytolytic factor was half‐maximally active at 3–25 ng protein/ml and lysed all tumor cells tested, but not normal cells.