title: Matrix metalloproteinase-2 and -9 lead to fibronectin degradation in astroglia infected with Toxoplasma gondii.
abstract: Toxoplasma gondii is a zoonotic parasite and its infection in human can induce toxoplasmic encephalitis in immune disorders. In this study, astroglia were infected with the TS-4 strain of T. gondii tachyzoite in vitro to investigate the changes of matrix metalloproteinase (MMP)-2, MMP-9 and their substrate fibronectin. MMP-2 and MMP-9 were significantly increased at 1 h, 6 h and 12 h post-infection (PI) in the cell homogenates, and increased at 6 h, 12 h, 24 h and 48 h PI in the cell-cultured supernatants. Fibronectin degradation also occurred at the same time points. In addition, immunocytochemistry showed that MMP-2 and MMP-9 localized in the cytoplasm, and confocal scanning laser microscopy revealed co-labeled patterns of MMP-2 and MMP-9 with fibronectin. MMP-2 and MMP-9 interacted with fibronectin, respectively. These results suggest that MMP-2 and MMP-9 induction from astroglia may contribute to extracellular matrix (ECM) degradation occurring in toxoplasmosis. Thus, we hypothesize that MMP-2 and MMP-9 cleave fibronectin and may contribute to the astroglia reaction and leukocyte migration to the sites of T. gondii replication during toxoplasmic encephalitis.
authors.affiliation: Institue of Medicine, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Cheng-You
authors.initials: CY
authors.lastname: Lu
authors.forename: Shih-Chan
authors.initials: SC
authors.lastname: Lai
mesh_terms: D001253:Astrocytes / Q000469:parasitology*; D002460:Cell Line; D003593:Cytoplasm / Q000201:enzymology; D005353:Fibronectins / Q000378:metabolism*; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D059748:Proteolysis; D014122:Toxoplasma / Q000472:pathogenicity*
chemical_list: D005353:Fibronectins; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9