Rabbit bone collagenase inhibitor blocks the activity of other neutral metalloproteinases.

Rabbit bone explants produce a collagenase inhibitor during the first few days in culture and later produce neutral metallo-proteinases, one of which is collagenase. We present evidence that the collagenase inhibitor also blocks the activity of the other neutral metalloproteinases (after activation by 4-amino-phenylmercuric acetate), indicating that one inhibitor may function as a single regulator for all the metalloproteinases involved in connective tisue catabolism.     

Purification of an Aspergillus oryzae Metallo-proteinase by Talopeptin-aminohexyl-Sepharose and Its Properties

Simple and speedy purification of Aspergillus oryzae metallo-proteinase was performed using Talopeptin-aminohexyl-Sepharose The properties of the metallo-proteinase were: optimum pH 6.5; pH stability, pH 5~11; optimum temperature,50°C; and molecular weight 42,000 (SDS electrophoresis). These results were similar to those of neutral protease I from Aspergillus oryzae reported by Nakadai et al. This metallo-proteinase was compared with others from microbes using the metallo-proteinase inhibitors FMPI, PLT, and Talopeptin. The metallo-proteinase is unique in the point at which FMPI and PLT gave nearly stoichiometrical inhibition.     

Extraction of collagenase from the 6000 times g sediment of uterine and skin tissues of mice. A comparative study.

An enzyme capable of digesting native collagen in solution at neutral pH was extracted from the 6 000 times g sediment of the involuting uterus of the mouse and of the back skins of mice and rats. The collagenase could be dissociated at cold-room temperature from the sediment in about equal amounts when neutral Tris buffer containing 1.0M NaCl or 5M urea was used for the extraction step. The enzyme has been concentrated by ammonium sulfate precipitation and the activity was measured by using [14C]collagen in solution at pH 7.5. Collagen breakdown products were identified by disc electrophoresis. The amount of enzyme extracted was a function of temperature and salt concentration. As 5M urea extracted collagenase from the sediment in a relatively short time, this method of extraction seems to be a useful tool for serial experiments in the study of collagenase activity in collagen-rich tissues.     

The presence of collagenase in collagen preparations.

The frequently observed instability of neutral salt solutions of native collagen extracted from various sources and partially purified by standard procedures has been studied by disc electrophoresis in polyacrylamide gel and by electron microscopic examination of segment long spacing crystallites. The phenomenon has revealed time and temperature dependency, pH optima near neutrality, and inhibition by sodium EDTA and serummin addition, collagen breakdown has been found to be quantitatively related to the state of aggregation of the substrate, being more marked in reconstituted collagen gels than in collagen in solutionma typical pattern of animal collagenase degradation of native collagen into two fragments designated as TC-A and TC-B has been observed under certain conditions. It is concluded that the degradation of native collagen in neutral salt solution is due to a specific collagenase, and that this enzyme probably remains bound to collagen throughout the process of extraction and partial purification. Experiments with gelatin suggest that, in addition to collagenase, a nonspecific proteolytic activity may also be present in collagen preparations.     

A component of normal human serum which enhances the activity of vertebrate collagenases.

The activity of vertebrate collagenase is increased by approximately 3-fold in the presence of saturating amounts of a macromolecule found in normal human serum. The activities of collagenases from human skin, rat skin, and tadpole tailfin are all markedly enhanced in the presence of this molecule, but activities of bacterial collagenase, trypsin, chymotrypsin, thermolysin, and a gelatin-specific neutral protease from human skin are unchanged. The enhancer itself has no proteolytic activity and does not change the normal cleavage products of human skin collagenase. The collagenase enhancer is an extremely stable molecule. It is resistant to heat, to extremes of pH at physiological temperature, and appears to be protein in nature. Of particular interest is the requirement that the collagen substrate be in fibrillar form in order for the enhancer to be effective.     

Purification of rabbit bone inhibitor of collagenase.

1. Rabbit bones in tissue culture synthesize an inhibitor of collagenase during the first 4 days of culture. 2. The inhibitor was purified by a combination of gel filtration, concanavalin A--Sepharose chromatography, ion-exchange chromatography and zinc-chelate affinity chromatography. 3. The purified inhibitor migrated as a single band on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and had a mol.wt. of 28000. 4. The inhibitor blocked the activity of the metalloproteinases collagenase, gelatinase, neutral proteinase III (proteoglycanase), human leucocyte collagenase and gelatinase, but not thermolysin or bacterial collagenase. The serine proteinases plasmin and trypsin were not inhibited. 5. The inhibitor interacted with purified rabbit bone collagenase with 1:1 stoichiometry. 6. The inhibitory activity was lost after incubation for 1 h at 90 degrees C, after treatment with trypsin (250 micrograms/ml) at 37 degrees C for 30 min and after reduction and alkylation.     

Purification of rheumatoid synovial collagenase and its action on soluble and insoluble collagen.

1. The neutral collagenase released into the culture medium by explants of ehrumatoid synovial tissue has been purified by ultrafiltration and column chromatography, utilising Sephadex G-200, Sephadex QAE A-50 and Sephadex G-100 superfine. 2. The final collagenase preparation had a specific activity against thermally reconstituted collagen fibrils of 312 mug collagen degraded min-1 mg enzyme protein-1, representing more than a 1000-fold increase over that of the active culture medium. 3. Electrophoresis in polyacrylamide disc-gels with and without sodium dodecyl sulphate showed the enzyme to migrate as a single protein band. Elution experiments from polyacrylamide gels and chromatography columns have provided no evidence for the existence of more than one collagenase. 4. The molecular weight of the enzyme, as determined by dodecylsulphate-polyacrylamide gel electrophoresis, was 33000. 5. Data obtained from sutdies with the ion-exchange resin and from gel electrophoresis in acid and alkaline buffer systems suggested a basically charged enzyme. 6. It did not hydrolyse the synthetic collagen peptide Pz-Pro-Leu-Gly-Pro-D-Arg and non-specific protease activity was absent. 7. The collagenase attacked undenatured collagen in solution at 25 degrees C resulting in a 58% loss of viscosity and producing the two characteristic products TCA(3/4) and TCB(1/4). 8. At 37 degrees C and pH 8.0 both reconstituted collagen fibrils and gelatin were degraded to peptides of less than 10000 molecular weight. 9. As judged by the release of soluble hydroxyproline peptides and electron microscopic appearances the enzyme degraded human insoluble collagens derived from tendon and soft juxta-articular tissues although rates of attack were less than with reconstituted fibrils. 10. The data suggests that pure rheumatoid synovial collagenase at 37 degrees C and neutral pH can degrade gelatin, reconstituted fibrils and insoluble collagens without the intervention of non-specific proteases. 11. The different susceptibilities of various collagenous substrates to collagenase attack are discussed.     

Effects of gonadotrophins, sex steroids and adenohypophysectomy on the activities of proteolytic enzymes in the ovarian follicle wall of the domestic fowl (Gallus domesticus)

LH and progesterone added to cultures of the follicle wall of hens increased the total activity of neutral and acid proteases and collagenase and the increase was greater for follicle tissues from the stigma region. Adenohypohysectomy of hens resulted in the decreased activities of neutral and acid proteases and collagenase in the first and second largest follicles.     

Enhancement of eosinophil effector function by soluble factors released by S. mansoni: role of proteases

Schistosomulum-released products (SRP) have been shown to enhance both expression of rat and human eosinophil Fc receptors and IgG-dependent cytotoxicity. The present work provides additional evidence of the secretion of eosinophil-enhancing factors by schistosomula and other developmental stages of schistosomes, including adult worms. The heat lability, as well as the strong inhibition of the stimulating activity of SRP by the protease inhibitor Trasylol, suggest that thermolabile proteases secreted by the parasite are involved in this mechanism. The purification of the schistosome proteases by preparative isoelectric focusing and gel filtration demonstrated that neutral proteases able to hydrolyze the collagenase substrates Azocoll and Z-Gly-Pro-Leu-Gly-Pro are able to significantly enhance eosinophil effector functions. Purified Clostridium histolyticum collagenase was also able to mimic the enhancing effect of schistosome proteases, suggesting involvement of a collagenase-like activity of the enzymes in the eosinophil stimulation.     

Strongyloides spp.: demonstration and partial characterization of acidic collagenolytic activity from infective larvae

Infective larvae of Strongyloides spp. have been shown to contain azocollytic enzymes which may aid in host skin penetration. Attempts to demonstrate classical, neutral pH-active collagenase activity in Strongyloides ratti were unsuccessful. In the current study, we investigated the presence of acidic collagenolytic activity in the infective larvae of Strongyloides ransomi, S. ratti, and S. stercoralis. All three species demonstrated collagenolytic activity in acidic homogenates as well as in neutral freeze-thaw fractions. Biochemical characterization of this collagenolytic activity from S. ratti and S. ransomi indicated that it was active over an acidic pH range, although it was stable at a neutral pH. This, along with molecular weight estimates and inhibitor susceptibilities, suggested that the collagenolytic activity was similar to vertebrate acidic cysteinyl proteinases. These studies also indicated that this activity is similar to the acidic cysteinyl proteinases in extracts of S. ransomi.     

Purification and properties of extracellular matrix-degrading metallo-proteinase overproduced by Rous sarcoma virus-transformed rat liver cell line, and its identification as transin

Rous sarcoma virus-transformed rat liver cell line RSV-BRL secreted a neutral proteinase in a latent precursor form with a molecular weight (Mr) of 57,000 (57k) as a major secreted protein. This enzyme was a calcium-dependent metallo-proteinase. The proenzyme was purified from the serum-free conditioned medium of the transformed cells by affinity chromatographies on a zinc chelate Sepharose column and a reactive red agarose column. When activated by treatment with trypsin or p-aminophenylmercuric acetate (APMA) in the presence of Ca2+, the purified enzyme effectively hydrolyzed casein, fibronectin, and laminin. Type IV collagen was hydrolyzed at 37 degrees C but not at 30 degrees C by the enzyme, whereas type I and type III collagens were hardly hydrolyzed even at 37 degrees C. The treatment with trypsin or AMPA in the presence of Ca2+ converted this 57k proenzyme to an active and stable enzyme with Mr 42k. In the absence of Ca2+, however, APMA converted the proenzyme to an intermediate form with Mr 45k, while trypsin digested it to an inactive peptide with Mr 30k. These results demonstrate that calcium ion is essential for the activation, activity expression, and stabilization of this metallo-proteinase. Analysis of its partial amino acid sequence and amino acid composition showed that the 57k proenzyme was identical or closely related to the putative protein transin, a rat homologue of stromelysin.     

Metalloproteinase activity in growth plate chondrocyte cultures is regulated by 1,25-(OH)(2)D(3) and 24,25-(OH)(2)D(3) and mediated through protein kinase C.

During endochondral development, growth plate chondrocytes must remodel their matrix in a number of ways as they differentiate and mature. In previous studies, we have shown that matrix metalloproteinases (MMPs) extracted from matrix vesicles can extensively degrade aggrecan and that this is modulated by vitamin D metabolites in a manner involving protein kinase C (PKC). Matrix vesicles represent only a small component of the extracellular matrix, however, and it is unknown if the total metalloproteinase complement, including the MMPs and aggrecanases in the culture, is also regulated in a similar way. This study tested the hypothesis that vitamin D metabolites regulate the level of metalloproteinase activity in growth plate chondrocytes via a PKC-dependent mechanism and play a role in partitioning this proteinase activity between the media and cell layer (cells+matrix) in these cultures. To do this, resting zone cells (RC) were treated with 10(-9)-10(-7) M 24R,25-(OH)(2)D(3), while growth zone cells (GC) were treated with 10(-10)-10(-8) M 1alpha,25-(OH)(2)D(3). Cultures of both cell types were also treated with the PKC inhibitor chelerythrine in the presence and absence of vitamin D metabolites. At harvest, the media were either left untreated or treated to destroy metalloproteinase inhibitors, while enzyme activity in the cell layers was extracted with buffered guanidine and then treated like the media to destroy metalloproteinase inhibitors. Neutral metalloproteinase (aggrecan-degrading activity) activity was assayed on aggrecan-containing polyacrylamide gel beads and collagenase activity was measured on telopeptide-free type I collagen. Neutral metalloproteinase activity was found primarily in the cell layer of both cell types; however, activity was greater in extracts of GC cell layers. No collagenase activity could be detected in RC extracts until the metalloproteinase inhibitors were destroyed. In contrast, extracts of GC cell layers contained measurable activity without removing the inhibitors, and destroying the inhibitors resulted in a greater than two-fold increase in activity. No collagenase activity was found in the media of either cell type. 24,25-(OH)(2)D(3) caused a dose-dependent increase in neutral metalloproteinase activity in extracts of RC cells, but had no effect on collagenase activity. In contrast, 1,25-(OH)(2)D(3) caused a dose-dependent decrease in collagenase activity in extracts of GC cells, but had no effect on neutral metalloproteinase activity. In both cases, the effect of the vitamin D metabolite was mediated through the activation of PKC. These results support the hypothesis that metalloproteinases are involved in regulating the bulk turnover of collagen and aggrecan in growth plate chondrocytes and that the amount of metalloproteinase activity found is a function of the cell maturation state. Furthermore, 83-93% of neutral metalloproteinase activity and 100% of collagenase activity is localized to the cell layer. Moreover, the regulation of metalloproteinase activity by 1,25-(OH)(2)D(3) and 24,25-(OH)(2)D(3) involves a PKC-dependent pathway that is controlled by the target cell-specific vitamin D metabolite.     

Inhibition of human collagenase activity by a small molecular weight serum protein.

Fractionation of human serum proteins by gel filtration in Sephadex G-200 revealed two regions of collagenase inhibition which corresponded to α₂-macroglobulin and a smaller serum component which eluted after α₁-antitrypsin. The smaller collagenase inhibitor, having a molecular weight of 40,000 was separated from α₁-antitrypsin by chromatography in Sephadex DEAE A.50. It was found to inhibit human collagenases derived from skin, rheumatoid synovium, gastric mucosa and granulocytes, but not the neutral proteases trypsin and papain. Purified preparations of α₁-antitrypsin inhibiting trypsin and papain had no effect on the collagenase activities. The small collagenase inhibitor may have importance as a regulatory factor in the control of collagenase activity in vivo.     

Synthesis and release of procollagenase by cultured fibroblasts.

An inactive collagenase was harvested from both serum-free and serum-supplemented fibroblast monolayer cultures in periods of active collagen synthesis. The latent collagenase did not hydrolyze collagen and did not bind the potent collagenase inhibitor alpha2-macroglobulin. Activation with trypsin imparted to the enzyme the ability to hydrolyze collagen at neutral pH in a typical manner and to form an inhibited complex with alpha2-macroglobulin. The molecular weights, determined by calibrated gel filtration, were 78,000 and 60,000 for the latent and active enzymes, respectively. The data indicate that collagenase is released from the cells in inactive form, as a zymogen.     

A latent collagenase from rheumatoid synovial fluid. Purification and partial characterization

1. A latent collagenase (EC 3.4.24.3) has been isolated from rheumatoid synovial fluids and purified by (NH4)2SO4 precipitation and column chromatography, utilising Sephadex G-150, DEAE Sephadex A-50 and Sephadex G-100 superfine grade. 2. The final preparation activated by trypsin (EC 3.4.21.4) had a specific activity against thermally reconstituted collagen fibrils of 259 micrograms collagen degraded/min per mg enzyme protein, representing a nearly 800-fold increase over that of the original rheumatoid synovial fluid. 3. The latent collagenase preparation can be activated by trypsin and to some extent by HgCl2 but not by 3 M NaSCN, 3.5 M NaCl, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) or p-chloromercuribenzoate. 4. Inhibition studies and the acrylamide gel electrophoretic pattern of collagen degradation products showed that the trypsin-activated enzyme has the essential features of a neutral collagenase. 5. The molecular weights, determined by calibrated gel filtration, were 52 000 and 43 000 for the latent and the activated enzyme, respectively. 6. The nature of the latency of synovial fluid collagenase is discussed.     

Activation of human breast carcinoma collagenase through plasminogen activator

Latent collagenase activity was detected in the media of a well-characterized line of human breast carcinoma cells maintained for over two years in culture. The media also contained sufficient plasminogen activator to convert extrinsically added plasminogen to plasmin which in turn activated the collagenase. During culture of the breast carcinoma in serum-free medium, collagenase activity was maximum on day 12 whereas plasminogen activator activity changed little with time. Using type I collagen as a substrate, the activated breast tumor collagenase produced $\text{3}\text{4}\text{?}\text{1}\text{4}$ fragments consistent with a mammalian collagenase. These findings suggest a pathologic role of plasminogen activator in the activation of latent collagenase during tumor invasion.A number of investigators have postulated that proteases may play a role in tumor invasion (1–5). Collagenase is one such protease which is active at neutral pH and specifically cleaves triple helical collagen into two ($\text{3}\text{4}\text{?}\text{1}\text{4}$ fragments (6). Secretion of collagenase by tumor cells migrating from the primary mass provides an attractive hypothesis for the mechanism of tumor invasion of surrounding host connective tissue—since the local environment would likely be at neutral pH. Consequently, a number of investigators have reported significant levels of collagenase activity in a wide variety of tumors (7–14). Abramson (13) has correlated aggressive $\text{in vivo}$ growth in carcinomas of the head and neck with collagenase activity, and Kuettner et al. (14) have postulated that inhibitors of collagenase may prevent tumors from invading cartilage.Collagenase is produced in both latent and active forms (6). The latent form can be activated with brief protease treatment (15). Since one of the proteases capable of activating collagenase is plasmin (15), the possibility arose that tumor cells could activate collagenase through plasminogen activator. Plasminogen activator secreted by tumor cells (4, 5) could convert plasminogen zymogen to plasmin which would in turn activate latent tumor collagenase. Testing this hypothesis $\text{in vitro}$ was the subject of the present study.Previous studies on collagenase from human carcinoma (7, 13, 14) have suffered from the drawback that contaminating inflammatory cells and fibroblasts may have been the source of the collagenase. Therefore, we have studied collagenase production from cultured human breast carcinoma cells which have been well characterized to be mammary epithelial in origin, malignant in karyotype, and able to grow in nude mice. Production of collagenase from these cells is therefore unequivocally of human carcinoma origin. The time course of latent collagenase and plasminogen activator secretion by these cultured tumor cells was studied following withdrawal of serum. To test whether plasminogen activator was secreted in sufficient amounts to indirectly activate latent collagenase, collagenase activity of the culture media was studied after the extrinsic addition of plasminogen. Finally, to verify that the tumor-secreted collagenase cleaved type I collagen at a single locus, enzyme degradation products were studied by gel electrophoresis.     

Proteoglycan-degrading enzymes of rabbit fibroblasts and granulocytes.

A neutral proteinase secreted by rabbit synovial fibroblasts in parallel with specific collagenase was partially purified by ion-exchange chromatography. At pH 7.6 this proteinase degraded 35S-labelled bovine nasal proteoglycan and azo-casein. The enzymic activity was inhibited by EDTA, 1,10-phenanthroline and serum, whereas di-isopropyl phosphorofluoridate and soya-bean trypsin inhibitor had little effect. By gel filtration the apparent mol.wt. of the enzyme was 25000. The fibroblast neutral proteinase was compared with the proteoglycan-degrading neutral proteinases of rabbit polymorphonuclear-leucocyte granules. Two distinct activities were found in the granules: one was inhibited by soya-bean trypsin inhibitor and the other by EDTA. The proteoglycan-degrading proteinases of rabbit fibroblasts and polymorphonuclear leucocytes at acid pH also were examined. Both cathepsin D and a thiol-dependent proteinase contributed to the degradation of proteoglycan at pH 4.5.     

Isolation of Metallo-proteinase Inhibitor (FMPI) Producing Microorganism

A screening test was carried out for the purpose of isolating a microorganism which produced a specific proteinase inhibitor for mold metallo-proteinase. A potent strain identified as Streptomyces rishiriensis was isolated, and this inhibitor was named fungal metallo-proteinase inhibitor (FMPI). The strain was aerobically cultured at 25°C for 26–30 hr in shaking flasks with a medium consisting of 1 % meat extract, 1 % polypepton and 0.3% NaCl (about 100 mg/liter). FMPI showed execellent inhibitory activity against the metallo-proteinase of Aspergillus oryzae, and moderate activity against other microbials. FMPI has a low molecular weight and is stable only at alkaline region (pH > 11).     

The presence of collagenase in collagen preparations

The frequently observed instability of neutral salt solutions of native collagen extracted from various sources and partially purified by standard procedures has been studied by disc electrophoresis in polyacrylamide gel and by electron microscopic examination of segment long spacing crystallites. The phenomenon has revealed time and temperature dependency, pH optima near neutrality, and inhibition by sodium EDTA and serum. In addition, collagen breakdown has been found to be quantitatively related to the state of aggregation of the substrate, being more marked in reconstituted collagen gels than in collagen in solution. A typical pattern of animal collagenase degradation of native collagen into two fragments designated as TC^A and TC^B has been observed under certain conditions. It is concluded that the degradation of native collagen in neutral salt solution is due to a specific collagenase, and that this enzyme probably remains bound to collagen throughout the process of extraction and partial purification. Experiments with gelatin suggest that, in addition to collagenase, a nonspecific proteolytic activity may also be present in collagen preparations.     

Collagenase and collagenolytic cathepsin in normal and fibrotic rat liver

Collagenase and collagenolytic cathepsin activities in normal and carbon tetrachloride-induced fibrotic livers of rats were simultaneously determined at 35 and 25 degrees C for 18 h, using the same 14C-labeled neutral soluble collagen as a substrate. Collagenolytic cathepsin had higher activity under the assay conditions at both 35 and 25 degrees C than collagenase in normal and fibrotic livers. On sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis, the collagen was visibly degraded by collagenolytic cathepsin, but not by collagenase. These results indicate that, unlike collagenase, collagenolytic cathepsins exist as active forms in the rat liver, and can participate in the degradation of collagens, especially of soluble collagens including procollagens.