Amoebocytes of the echinoderm (sea urchin), Paracentrotus lividus are responsible for cytotoxic activity. The cytotoxic event requires contact between effector and target cells and calcium-dependent hemolysins, causing disintegration and lysis of target cells. The amoebocytes contain cytoplasmic, lytic granules which are electron-dense and lucid. Isolated granules consist of morphologically empty vesicles. Acid, but not alkaline, proteases were the degradative enzyme constituents of isolated amoebocyte granules. The similarity of mammalian NK cells and putative equivalents in sea urchins is discussed and compared with respect to the evolution of cytotoxicity.
Structure and enzyme content of sea urchin cytolytic granules
PAGLIARA, Patrizia;
1993-01-01
Abstract
Amoebocytes of the echinoderm (sea urchin), Paracentrotus lividus are responsible for cytotoxic activity. The cytotoxic event requires contact between effector and target cells and calcium-dependent hemolysins, causing disintegration and lysis of target cells. The amoebocytes contain cytoplasmic, lytic granules which are electron-dense and lucid. Isolated granules consist of morphologically empty vesicles. Acid, but not alkaline, proteases were the degradative enzyme constituents of isolated amoebocyte granules. The similarity of mammalian NK cells and putative equivalents in sea urchins is discussed and compared with respect to the evolution of cytotoxicity.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
