title: Membrane-type matrix metalloproteinases in human dermal microvascular endothelial cells: expression and morphogenetic correlation.
abstract: Membrane-type matrix metalloproteinases (MT-MMP) activate the zymogen form of MMP-2/Gelatinase A on cell surfaces and are expressed in invasive tumors. We sought to identify and characterize MT-MMP in a non-malignant cell type that undergoes a physiologic and reversible invasive phenotype during angiogenesis. Human dermal microvascular endothelial cells (HDMEC) were isolated from neonatal tissue and purified by anti-CD31 (PECAM) affinity beads. MT-MMP-1 and -3 transcripts were amplified by reverse transcriptase-polymerase chain reaction and northern blots showed a single 4.5 kB mRNA for MT-MMP-1 that was modulated by angiogenic factors and phorbol ester. Immunoblotting of reduced cellular extracts with different MT-MMP-1 antibodies showed the presence of the 63-65 kDa and 57-60 kDa forms, as well as additional forms at lower molecular weights. HDMEC membranes extracted with Triton X114 were incubated with gelatin-sepharose purified MMP-2 and MMP-9 to show activation of proenzymes. Pre-incubation of HDMEC with anti-MT-MMP-1 antibodies decreased proMMP-2 conversion activity only. The movement of HDMEC and the formation of tubule-like structures in three-dimensional collagen gels was markedly delayed by preincubation with the same anti-MT-MMP-1 antibodies. These results demonstrate the presence of MT-MMP in cutaneous microvascular cells in vitro. Modulation of these cell surface proteinases by angiogenic factors, demonstration of multiple processed forms, and specific attenuation of HDMEC morphogenetic patterns in three-dimensional collagen gels implicate their potential roles in the formation of new blood vessels in the skin.
authors.affiliation: Department of Dermatology, Stanford University School of Medicine, California 94305, USA.
authors.forename: V T
authors.initials: VT
authors.lastname: Chan
authors.forename: D N
authors.initials: DN
authors.lastname: Zhang
authors.forename: U
authors.initials: U
authors.lastname: Nagaravapu
authors.forename: K
authors.initials: K
authors.lastname: Hultquist
authors.forename: L I
authors.initials: LI
authors.lastname: Romero
authors.forename: G S
authors.initials: GS
authors.lastname: Herron
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000494:pharmacology; D019138:Antibodies, Blocking / Q000276:immunology; D004730:Endothelium, Vascular / Q000166:cytology*; D004789:Enzyme Activation / Q000276:immunology; D004792:Enzyme Precursors / Q000378:metabolism; D018093:Gelatinases / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D015151:Immunoblotting; D007231:Infant, Newborn; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008833:Microcirculation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000098:blood supply*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D043925:Angiogenesis Inducing Agents; D019138:Antibodies, Blocking; D004792:Enzyme Precursors; D018093:Gelatinases; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases; C069860:progelatinase