T-cell production of matrix metalloproteinases and inhibition of parasite clearance by TIMP-1 during chronic Toxoplasma infection in the brain

ASN Neuro. 2011 Jan 21;3(1):e00049. doi: 10.1042/AN20100027.

Abstract

Chronic infection with the intracellular protozoan parasite Toxoplasma gondii leads to tissue remodelling in the brain and a continuous requirement for peripheral leucocyte migration within the CNS (central nervous system). In the present study, we investigate the role of MMPs (matrix metalloproteinases) and their inhibitors in T-cell migration into the infected brain. Increased expression of two key molecules, MMP-8 and MMP-10, along with their inhibitor, TIMP-1 (tissue inhibitor of metalloproteinases-1), was observed in the CNS following infection. Analysis of infiltrating lymphocytes demonstrated MMP-8 and -10 production by CD4+ and CD8+ T-cells. In addition, infiltrating T-cells and CNS resident astrocytes increased their expression of TIMP-1 following infection. TIMP-1-deficient mice had a decrease in perivascular accumulation of lymphocyte populations, yet an increase in the proportion of CD4+ T-cells that had trafficked into the CNS. This was accompanied by a reduction in parasite burden in the brain. Taken together, these findings demonstrate a role for MMPs and TIMP-1 in the trafficking of lymphocytes into the CNS during chronic infection in the brain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / metabolism
  • Astrocytes / parasitology
  • Brain / immunology
  • Brain / parasitology
  • Brain / pathology*
  • CD4 Antigens
  • CD4-Positive T-Lymphocytes / metabolism*
  • CD8-Positive T-Lymphocytes / metabolism*
  • Caseins
  • Cells, Cultured
  • Cytokines / metabolism
  • Disease Models, Animal
  • Flow Cytometry
  • Matrix Metalloproteinases / genetics
  • Matrix Metalloproteinases / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Peptide Fragments
  • RNA, Messenger / metabolism
  • Time Factors
  • Tissue Inhibitor of Metalloproteinase-1 / deficiency
  • Tissue Inhibitor of Metalloproteinase-1 / metabolism*
  • Toxoplasmosis / pathology*
  • Toxoplasmosis / physiopathology
  • Up-Regulation / genetics

Substances

  • CD4 Antigens
  • Caseins
  • Cytokines
  • Peptide Fragments
  • RNA, Messenger
  • Tissue Inhibitor of Metalloproteinase-1
  • KNQDK peptide
  • Matrix Metalloproteinases