An integrative approach to the proteolytic control of the cell-mediated cytotoxicity.
The possible role of intracellular proteases in the control of the cell-mediated cytotoxicity of NK or CTL type, as components of the sequential molecular events leading to the target cell lysis, is emphasized by an integrative structural and functional approach. Starting from the own cytochemical researches and based on recent data, the effector cell proteases are analysed concerning their cellular and ultrastructural compartmentalization and their involvement in the sequential stages of the cytotoxic cycle. Membranous, granular, lysosomal and cytosolic compartments of the proteolytic activity are differentially elicited to interfere in the stimulus-secretion pattern of the cytotoxic function. Serine proteases (trypsin and chymotrypsin-like) and thiol proteases (calpain, cathepsins B and L) are specifically involved in the receptor-mediated signal transduction by the phosphatidyl inositol pathway, in the programming of the secretory machinery, in the exocytosis of the cytotoxic factors and in the final lytic phase. An integrative model of the cell-mediated cytotoxicity is proposed including the protease compartments of the effector cell and their specific involvement in the triggering, the modulation and the control of the cellular and molecular events, as main components of the informational networks of the cytotoxic cells.
Gabrielescu
E
E
Victor Babeş Institute, Bucharest, Romania.
D000818:Animals; D003594:Cytoplasmic Granules / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D003602:Cytotoxicity, Immunologic / Q000502:physiology*; D010450:Endopeptidases / Q000502:physiology*; D006801:Humans; D007694:Killer Cells, Natural / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D008247:Lysosomes / Q000201:enzymology; D051379:Mice; D008954:Models, Biological; D011956:Receptors, Cell Surface / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000201:enzymology / Q000276:immunology / Q000378:metabolism
D011956:Receptors, Cell Surface; D010450:Endopeptidases