Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0014070 (encephalomyelitis)
 13,017 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Matrix metalloproteinases (MMPs) comprise a group of proteolytic enzymes that are implicated in the pathogenesis of inflammatory diseases of the nervous system such as multiple sclerosis. However, the exact function and expression pattern of MMPs in the inflamed nervous system are not known. In the present study we investigated the expression of 92-kDa gelatinase (MMP-9) in spinal cord from animals with adoptive transfer experimental autoimmune encephalomyelitis (AT-EAE), using a semiquantitative competitive reverse transcriptase-polymerase chain reaction assay. Increased levels of MMP-9 mRNA were found with peak values at times of maximum disease severity. Increased mRNA expression was associated with enhanced proteolytic activity of this enzyme, as demonstrated by gelatin zymography. Immunohistochemistry revealed immunoreactivity along the meninges, around blood vessels and within the parenchyma, in diseased but not in normal spinal cord. Furthermore, the expression pattern of five other MMPs was investigated. Matrilysin (MMP-7) was also found to be upregulated with maximum mRNA levels at the peak of the disease. In contrast, mRNAs for collagenase-3, 72-kDa gelatinase, and stromelysin-1 and -3 were not changed. Our findings indicate that 92-kDa gelatinase and matrilysin are selectively upregulated during AT-EAE and thus may contribute to the pathogenesis of inflammatory diseases of the CNS.
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PMID:Matrix metalloproteinase-9 and -7 are regulated in experimental autoimmune encephalomyelitis. 954 96

Matrix metalloproteinase-2 (MMP-2; gelatinase A) is known to degrade a broad range of extracellular matrix components and chemokines, and has important roles in the processes of cell migration, invasion, and involution during development, as well as during tumor growth and metastasis and in inflammation and repair. To better elucidate the roles of this matrix metalloproteinase in the development and progression of experimental autoimmune encephalomyelitis, we used MMP-2-deficient (KO) mice. Surprisingly, we found that MMP-2 KO mice exhibited an earlier onset and more severe disease than did their wild-type (WT) counterparts. WT mice engrafted with MMP-2 KO bone marrow exhibited a similar earlier onset and more severe clinical disease score than WT mice engrafted with WT bone marrow. Lymphocytes derived from MMP-2 KO mice exhibited increased transmigration through endothelial cell monolayers as well as through collagen type IV and laminin-coated BD BIOCOAT inserts, which correlated with a 3-fold increase in expression of MMP-9 and was abrogated by inhibition of MMP activity. We demonstrated a correlation between expression levels of MMP-9 and MT1-MMP expression and suggest a signaling pathway involving tethering of MMP-2 to MT1-MMP as a modulator of MMP-9 expression. Last, we discuss other possible MMP-2-mediated mechanisms which may contribute to the observed phenotype.
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PMID:MMP-2 null mice exhibit an early onset and severe experimental autoimmune encephalomyelitis due to an increase in MMP-9 expression and activity. 1552 13

Effective recovery of activated brain infiltrating lymphocytes is critical for investigations involving murine neurological disease models. To optimize lymphocyte recovery, we compared two isolation methods using brains harvested from seven-day Theiler's murine encephalomyelitis virus (TMEV) and TMEV-OVA infected mice. Brains were processed using either a manual dounce based approach or enzymatic digestion using type IV collagenase. The resulting cell suspensions from these two techniques were transferred to a percoll gradient, centrifuged, and lymphocytes were recovered. Flow cytometric analysis of CD45hi cells showed greater percentage of CD44hiCD62lo activated lymphocytes and CD19+ B cells using the dounce method. In addition, we achieved a 3-fold greater recovery of activated virus-specific CD8 T cells specific for the immunodominant Db:VP2121-130 and engineered Kb:OVA257-264 epitopes through manual dounce homogenization approach as compared to collagenase digest. A greater percentage of viable cells was also achieved through dounce homogenization. Therefore, we conclude that manual homogenization is a superior approach to isolate activated T cells from the mouse brain.
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PMID:Superior isolation of antigen-specific brain infiltrating T cells using manual homogenization technique. 2762 24

The enzymes gelatinase A/matrix metalloproteinase-2 (MMP-2) and gelatinase B/MMP-9 are essential for induction of neuroinflammatory symptoms in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis (MS); in the absence of these enzymes, the disease does not develop. We therefore investigated the cellular sources and relative contributions of MMP-2 and MMP-9 to disease at early stages of EAE induction. We demonstrated that MMP-9 from an immune cell source is required in EAE for initial infiltration of leukocytes into the central nervous system and that MMP-9 activity is a reliable marker of leukocyte penetration of the blood-brain barrier. We then developed a molecular imaging method to visualize MMP activity in the brain using fluorescent- and radioactive-labeled MMP inhibitors (MMPis) in EAE animals and used the radioactive MMP ligand for positron emission tomography (PET) imaging of MMP activity in patients with MS. In contrast to traditional T1-gadolinium contrast-enhanced MRI, MMPi-PET enabled tracking of MMP activity as a unique feature of early lesions and ongoing leukocyte infiltration. MMPi-PET therefore allows monitoring of the early steps of MS development and provides a sensitive, noninvasive means of following lesion formation and resolution in murine EAE and human MS.
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PMID:Imaging matrix metalloproteinase activity in multiple sclerosis as a specific marker of leukocyte penetration of the blood-brain barrier. 2788 2