title: In vivo imaging of matrix metalloproteinase 12 and matrix metalloproteinase 13 activities in the mouse model of collagen-induced arthritis.
abstract: OBJECTIVE
  To develop enzyme-activatable Förster resonance energy transfer (FRET) substrate probes to detect matrix metalloproteinase 12 (MMP-12) and MMP-13 activities in vivo in mouse models of inflammatory arthritis.
  
  
  METHODS
  Peptidic FRET probes activated by MMP-12 and MMP-13 were reverse designed from inhibitors selected from a phosphinic peptide inhibitor library. Selectivity of the probes was demonstrated in vitro using MMP-1, MMP-2, MMP-3, MMP-12, and MMP-13. In vivo activation of the probes was tested in the zymosan-induced mouse model of inflammation, and probe specificity was evaluated by the MMP inhibitor GM6001 and specific synthetic inhibitors of MMP-12 and MMP-13. The probes were used to monitor these enzyme activities in the collagen-induced arthritis (CIA) model in vivo.
  
  
  RESULTS
  The MMP-12 and MMP-13 activity probes (MMP12ap and MMP13ap, respectively) discriminated between the activities of the 2 enzymes. The in vivo activation of these probes was inhibited by GM6001 and by their respective specific inhibitors. In the CIA model, MMP12ap activation peaked 5 days after disease onset and showed strong correlation with disease severity during this time (r = 0.85, P < 0.0001). MMP13ap activation increased gradually after disease onset and correlated with disease severity over a longer period of 15 days (r = 0.58, P < 0.0001).
  
  
  CONCLUSIONS
  We generated two selective FRET probes that can be used to monitor MMP-12 and MMP-13 activities in live animals. MMP12ap follows the initial stage of inflammation in CIA, while MMP13ap follows the progression of the disease. The specificity of these probes is useful in monitoring the efficacy of MMP inhibitors.
authors.affiliation: Kennedy Institute of Rheumatology and University of Oxford, Oxford, UK.
authors.forename: Ngee Han
authors.initials: NH
authors.lastname: Lim
authors.forename: Ernst
authors.initials: E
authors.lastname: Meinjohanns
authors.forename: George
authors.initials: G
authors.lastname: Bou-Gharios
authors.forename: Luke L
authors.initials: LL
authors.lastname: Gompels
authors.forename: Elisa
authors.initials: E
authors.lastname: Nuti
authors.forename: Armando
authors.initials: A
authors.lastname: Rossello
authors.forename: Laurent
authors.initials: L
authors.lastname: Devel
authors.forename: Vincent
authors.initials: V
authors.lastname: Dive
authors.forename: Morten
authors.initials: M
authors.lastname: Meldal
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nagase
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental / Q000201:enzymology*; D003952:Diagnostic Imaging; D031541:Fluorescence Resonance Energy Transfer; D053508:Matrix Metalloproteinase 12 / Q000378:metabolism*; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism*; D061965:Matrix Metalloproteinase Inhibitors / Q000494:pharmacology; D051379:Mice; D013583:Synovial Membrane / Q000187:drug effects / Q000201:enzymology*
chemical_list: D061965:Matrix Metalloproteinase Inhibitors; D053509:Matrix Metalloproteinase 13; D053508:Matrix Metalloproteinase 12