Purification and characterization of a new tissue inhibitor of metalloproteinases (TIMP-2) from mouse colon 26 tumor cells

Sonic extracts from a bacterium related to periapical disease activate gelatinase A and inactivate tissue inhibitor of metalloproteinases TIMP-1 and TIMP-2

AIM

To examine the effects of sonicated bacterial extracts (SBEs) from three related to periapical disease bacteria (Porphyromonas gingivalis, P. endodontalis and F. nucleatum) on the activation of matrix metalloproteinase (MMP-2) and the inactivation of tissue inhibitors of metalloproteinase (TIMP-1 and TIMP-2).

METHODOLOGY

Each SBE was added to cultures of human periodontal ligament (PL) cells or HT1080 cells and their supernatants were analysed by zymography for MMP-2. Each SBE was added to PL cell cultures, and the amount of TIMP-1 was determined by ELISA. P. gingivalis SBE was incubated with HT1080 cell culture supernatants, and the amounts of TIMP-1 and TIMP-2 were determined by ELISA. Statistical analysis was performed with the paired Student's t-test.

RESULTS

In extracts of PL cells that had been incubated in the presence of P. gingivalis SBE, one representing pro-MMP-2 (72 kDa) and a band corresponding to the active MMP-2 (66 kDa) were observed; but in the other extracts it was not detected. When HT1080 cells were treated with P. gingivalis SBE, the pro-MMPs was processed into 86- and 66-kDa fragments, but in the other extracts, the processing did not occur when the other SBEs were used. When PL cells were incubated with the same SBEs, the amount of TIMP-1 was markedly decreased (P < 0.01), but in the other extracts, it was not. The amounts of both TIMP-1 and TIMP-2 were decreased in a dose-dependent manner when HT1080 cell culture supernatant was incubated with P. gingivalis SBE.

CONCLUSIONS

These findings suggest that P. gingivalis SBE may cause connective tissue to be destroyed, contributing to the process of periapical disease, by activating pro-MMP-2 as well as by inactivating TIMP-1 and TIMP-2.

Interaction between tissue inhibitor of metalloproteinases-2 and progelatinase A: immunoreactivity analyses

By immunoreactivity analysis using monoclonal antibodies, we showed that the C-terminal domain [R415-631; R is residue] of progelatinase A [pro-matrix metalloproteinase-2 (proMMP-2); EC 3.4.24.24] affected the immunoreactivity of a one-step sandwich enzyme immunoassay (sandwich EIA) for tissue inhibitor of metalloproteinases-2 (TIMP-2) in exactly the same way as does proMMP-2 [Fujimoto, Zhang, Iwata, Shinya, Okada and Hayakawa (1993) Clin. Chim. Acta 220, 31-45], confirming that the C-terminal domain ("tail" portion of TIMP-2 participates in the binding with the C-terminal domain of proMMP-2. We also demonstrated that not only the C-terminal domain but also the N-terminal domain (R1-417) of proMMP-2 bound to TIMP-2 in a 1:1 molar ratio. The binding of each individual domain to TIMP-2, however, was weak enough that either domain could be fully replaced by proMMP-2 through the same binding sites as does proMMP-2, and also that the high-order structure of proMMP-2 allows a more stable binding to TIMP-2. We further confirmed that TIMP-2 complexed with the N-terminal domain of pro-MMP-2 had fully inhibitory activity against the collagenolytic activity of MMP-1. We also demonstrated that either the interstitial collagenase-TIMP-2 complex or the gelatinase B(MMP-9)-TIMP-2 complex was able to form a ternary complex with proMMP-2 in a 1:1 molar ratio, clearly indicating that there are two distinct binding sites, one specific for proMMP-2 complex, but the binding seemed to be less stable than the binding with TIMP-2 alone. Even in the presence of a 10-fold molar excess of the N-terminal domain, ternary complex formation was not observed between the N-terminal domain and the MMP-9--TIMP-2 complex. These clear differences might be ascribed to some significant conformational change(s) evoked in the TIMP-2 molecule, or hindrance of a part of the N-terminal domain binding site of TIMP-2 by complex formation with MMP-9.

Cell growth-promoting activity of tissue inhibitor of metalloproteinases-2 (TIMP-2)

Human tissue inhibitor of metalloproteinases-2 (TIMP-2) has a potent growth-promoting activity for wide range of human, bovine and mouse cells, having an optimal concentration (10 ng/ml, 0.46 nM) that is ten-times lower than that of TIMP-1 (Hayakawa et al. (1992) FEBS Lett. 298, 29). Neither TIMP-1 complexed with progelatinase B nor TIMP-2 complexed with progelatinase A, both of which have full inhibitory activity against active forms of matrix metalloproteinases (MMPs), showed any cell growth-promoting activity. On the contrary, both reductively alkylated TIMPs had no MMP inhibitory activity, but significantly stimulated cell proliferation. These facts clearly indicate that the cell-proliferation. These facts clearly indicate that the cell-proliferating activity of TIMPs is independent of MMP inhibitory activity. We also demonstrated that [3H]thymidine was significantly incorporated into Raji cells, a Burkitt lymphoma cell line, in the presence of either 4 ng/ml of TIMP-1 or 0.1 ng/ml of TIMP-2. Under steady-state conditions at 4 degrees C, high-(Kd = 0.15 nM) and low-(35 nM) affinity binding sites for TIMP-2 were identified on Raji cells with 20,000 and 1.4 × 10(5) sites/cell, respectively. Both high- and low-affinity binding of 125I-TIMP-2 to Raji cells were competitively inhibited by unlabeled TIMP-2 but not by unlabeled TIMP-1, suggesting the presence of receptors for TIMP-2 independent from those for TIMP-1. TIMP-2 seems to be another new TIMP cell-growth factor in serum, besides TIMP-1.

Purification and characterization of two collagenase inhibitors from mouse sarcoma 180 conditioned medium

We have previously shown that mouse sarcoma 180 cells produce vascular endothelial growth factor [VEGF; Rosenthal et al., 1990, Growth Factors, 4: 53-59], an endothelial mitogen that stimulates angiogenesis. Recent reports have implicated metalloproteinases and their inhibitors in the regulation of vascular morphogenesis, tumor invasion, and metastasis. We report here that mouse sarcoma 180 cells produce two collagenase inhibitors. These inhibitors were purified by heparin-Sepharose affinity chromatography, gel filtration, and C4 reverse phase h.p.l.c. Analytical gel electrophoresis of the purified inhibitors (MS-22 and MS-31) revealed molecular masses of 22,000 and 31,000 Da under reducing conditions, and 20,000 and 30,000 Da under nonreducing conditions, respectively. The NH2-terminal amino acid sequence of MS-22 was identical to that of tissue inhibitor of metalloproteinases type 2 (TIMP-2) produced by human melanoma cells [Stetler-Stevenson et al., 1989, J. Biol. Chem. 264: 17374-17378) over the first 30 amino acids. The NH2-terminal amino acid sequence of MS-31 was identical to that of murine TIMP-1 [Gewert et al., 1989, EMBO J 6:651-657]. Statistical analysis of the amino acid composition data of these two mouse sarcoma 180-derived collagenase inhibitors confirms the identification of MS-22 as TIMP-2 and MS-31 as TIMP-1.

Identification of tissue inhibitor of metalloproteinases-1 (TIMP-1) in human teeth and its distribution in cementum and dentine

An inhibitory activity toward matrix metalloproteinases such as interstitial collagenase, 72-kDa gelatinase/type IV collagenase, and stromelysin-1 was detected in an EDTA extract of pulverized roots of human teeth, and identified as TIMP-1 by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and immunoblotting. Distribution of TIMP-1 in human cementum and dentine was investigated by a sandwich enzyme immunoassay in combination with an abrasive microsampling technique. TIMP-1 could not be detected in cementum from some teeth but in others decreased from a fairly low value at the surface towards the cementodentinal junction. TIMP-1 concentrations in the dentine increased consistently from the cementodentinal junction toward the predentine. The average TIMP-1 concentration in the dentine (54.1 +/- 18.5 pg/mg +/- SE) was significantly (P < 0.05) higher than that (9.6 +/- 6.0 pg/mg +/- SE) in the cementum.

Identification of tissue inhibitor of metalloproteinase-2 (TIMP-2)-progelatinase complex as the third metalloproteinase inhibitor peak in rheumatoid synovial fluid

The metalloproteinases are a family of enzymes that can degrade all the components of the extracellular matrix. These potent enzymes are often found in proenzyme forms and require activation before the substrate can be digested. To prevent unlimited connective tissue destruction a number of inhibitors exist to limit their activity. In a previous study it was found that metalloproteinases in proenzyme form and metalloproteinase inhibitors were often present in rheumatoid synovial fluids. Two of these inhibitors were identified in rheumatoid synovial fluid as alpha 2 macroglobulin and tissue inhibitor of metalloproteinase (TIMP), the specific metalloproteinase inhibitor. A third inhibitory peak was unidentified. In the study reported here it was shown that this third inhibitor can be purified using gelatin-Sepharose chromatography and consists of TIMP-2 bound to progelatinase (relative molecular weight 72,000) in a similar way to that found in concentrated connective tissue culture medium. The importance of these proteinase inhibitors in synovial fluid is discussed.

Large inhibitor of metalloproteinases (LIMP) contains tissue inhibitor of metalloproteinases (TIMP)-2 bound to 72,000-M(r) progelatinase

Connective-tissue cells in culture produce a family of metalloproteinases which, once activated, can degrade all the components of the extracellular matrix. These potent enzymes are all inhibited by the tissue inhibitor of metalloproteinases (TIMP), and it was thought that this inhibitor was solely responsible for the inhibition of these enzymes within connective tissue. However, other inhibitors have recently been described, including large inhibitor of metalloproteinases (LIMP) present in the culture medium of human foetal lung fibroblasts. Here we show that a large proportion of the inhibitory activity of LIMP consists of 72,000-M(r)-progelatinase bound to TIMP-2, a recently discovered low-M(r) metalloproteinase inhibitor closely related to TIMP. The physiological implications of the secretion of a complex of 72,000-M(r) progelatinase and TIMP-2 are discussed, and the separation of the complex in 6 M-urea is described.

Cloning and sequencing of the cDNA encoding a mouse tissue inhibitor of metalloproteinase-2

A mouse cDNA encoding a tissue inhibitor of metalloproteinases (mTIMP-2) was cloned and the 1695-bp sequence was determined. While high homology was observed with the sequences encoding the human (hTIMP-2) and bovine (bTIMP-2) genes, mTIMP-2 contained a long 3'-nontranslated region not observed in the hTIMP-2 or bTIMP-2 genes.

Growth-promoting activity of tissue inhibitor of metalloproteinases-1 (TIMP-1) for a wide range of cells. A possible new growth factor in serum

Human tissue inhibitor of metalloproteinases-1 (TIMP-1), but not TIMP-2, has potent growth-promoting activity for a wide range of human and bovine cells. TIMP-1 seems to be a new cell-growth factor in serum and to stimulate the cells independently of its inhibitory activity.