Biomaterial Database

Hydrolysis of myelin basic protein in myelin membranes by granzymes of large granular lymphocytes. 1993

P Vanguri, and E Lee, and P Henkart, and M L Shin

Department of Pathology, University of Maryland, Baltimore 21201.

Immune-mediated demyelination initially manifests as a separation of myelin lamellae followed by loss of myelin proteins and eventual loss of myelin membranes. Myelin basic protein, one of the major structural proteins of myelin, is highly vulnerable to various proteases derived from diverse cell types. Killer lymphocytes such as CTL, in addition to other immune effectors, have been implicated in inflammatory demyelination. In addition to a pore forming peptide, the granules of CTL and large granular lymphocytes (LGL) contain a number of serine esterases collectively called as granzymes. We studied the effect of these granule enzymes on myelin and found that LGL granule-extracts (LGL-g) hydrolyzed MBP in myelin membranes. LGL-g also cleaved purified MBP at neutral pH in a Ca2+ independent manner and this hydrolysis was inhibited by serine esterase inhibitors. In addition, absorption of LGL-g with antigranzyme A significantly reduced MBP hydrolysis. These findings implicated the granzymes in LGL-g, especially granzyme A, as the agent causing MBP degradation. Inasmuch as activation of CTL in the vicinity of myelinated axons can lead to granule exocytosis, hydrolysis of MBP by granzymes may be a significant event in myelin destruction.

UI	MeSH Term	Description	Entries
D007106	Immune Sera	Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.	Antisera,Immune Serums,Sera, Immune,Serums, Immune
D007694	Killer Cells, Natural	Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.	NK Cells,Natural Killer Cells,Cell, NK,Cell, Natural Killer,Cells, NK,Cells, Natural Killer,Killer Cell, Natural,NK Cell,Natural Killer Cell
D009186	Myelin Sheath	The lipid-rich sheath surrounding AXONS in both the CENTRAL NERVOUS SYSTEMS and PERIPHERAL NERVOUS SYSTEM. The myelin sheath is an electrical insulator and allows faster and more energetically efficient conduction of impulses. The sheath is formed by the cell membranes of glial cells (SCHWANN CELLS in the peripheral and OLIGODENDROGLIA in the central nervous system). Deterioration of the sheath in DEMYELINATING DISEASES is a serious clinical problem.	Myelin,Myelin Sheaths,Sheath, Myelin,Sheaths, Myelin
D011480	Protease Inhibitors	Compounds which inhibit or antagonize biosynthesis or actions of proteases (ENDOPEPTIDASES).	Antiprotease,Endopeptidase Inhibitor,Endopeptidase Inhibitors,Peptidase Inhibitor,Peptidase Inhibitors,Peptide Hydrolase Inhibitor,Peptide Hydrolase Inhibitors,Peptide Peptidohydrolase Inhibitor,Peptide Peptidohydrolase Inhibitors,Protease Antagonist,Protease Antagonists,Antiproteases,Protease Inhibitor,Antagonist, Protease,Antagonists, Protease,Hydrolase Inhibitor, Peptide,Hydrolase Inhibitors, Peptide,Inhibitor, Endopeptidase,Inhibitor, Peptidase,Inhibitor, Peptide Hydrolase,Inhibitor, Peptide Peptidohydrolase,Inhibitor, Protease,Inhibitors, Endopeptidase,Inhibitors, Peptidase,Inhibitors, Peptide Hydrolase,Inhibitors, Peptide Peptidohydrolase,Inhibitors, Protease,Peptidohydrolase Inhibitor, Peptide,Peptidohydrolase Inhibitors, Peptide
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D004676	Myelin Basic Protein	An abundant cytosolic protein that plays a critical role in the structure of multilamellar myelin. Myelin basic protein binds to the cytosolic sides of myelin cell membranes and causes a tight adhesion between opposing cell membranes.	Golli-MBP1 Protein,Golli-MBP2 Protein,HOG5 Protein,HOG7 Protein,MBP1 Protein,MBP2 Protein,MBP3 Protein,MBP4 Protein,Myelin Basic Protein, 17.2 kDa Isoform,Myelin Basic Protein, 18.5 kDa Isoform,Myelin Basic Protein, 20.2 kDa Isoform,Myelin Basic Protein, 21.5 kDa Isoform,Myelin Basic Protein, Isoform 1,Myelin Basic Protein, Isoform 2,Myelin Basic Protein, Isoform 3,Myelin Basic Protein, Isoform 4,Myelin Basic Protein, Isoform 5,Myelin Basic Protein, Isoform 6,Myelin Basic Protein, Isoform 7,Golli MBP1 Protein,Golli MBP2 Protein
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.