scholarly journals Latent transforming growth factor-beta 1 associates to fibroblast extracellular matrix via latent TGF-beta binding protein

1994 ◽  
Vol 124 (1) ◽  
pp. 171-181 ◽  
Author(s):  
J Taipale ◽  
K Miyazono ◽  
CH Heldin ◽  
J Keski-Oja
Keyword(s):  
Molecular Weight ◽  
Extracellular Matrix ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Binding Protein ◽  
Free Form ◽  
Tgf Beta ◽  
The Matrix ◽  
Growth Factor Beta

The role of latent transforming growth factor-beta (TGF-beta) binding protein (LTBP) in the association of TGF-beta 1 to the extracellular matrix of cultured fibroblasts and HT-1080 fibrosarcoma cells was studied by immunochemical methods. The matrices were isolated from the cells, and the levels of LTBP and TGF-beta 1 were estimated by immunoblotting and immunoprecipitation. LTBP, TGF-beta 1, and its propeptide (latency-associated peptide, LAP) were found to associate to the extracellular matrix. Immunoblotting analysis indicated that treatment of the cells with plasmin resulted in a concomitant time and dose dependent release of both LTBP and TGF-beta 1 from the extracellular matrix to the supernatant. Comparison of molecular weights suggested that plasmin treatment resulted in the cleavage of LTBP from the high molecular weight fibroblast form to a form resembling the low molecular weight LTBP found in platelets. Pulse-chase and immunoprecipitation analysis indicated that both the free form of LTBP and LTBP complexed to latent TGF-beta were efficiently incorporated in the extracellular matrix, from where both complexes were slowly released to the culture medium. Addition of plasmin to the chase solution resulted, however, in a rapid release of LTBP from the matrix. Fibroblast derived LTBP was found to associate to the matrix of HT-1080 cells in a plasmin sensitive manner as shown by immunoprecipitation analysis. These results suggest that the latent form of TGF-beta 1 associates with the extracellular matrix via LTBP, and that the release of latent TGF-beta 1 from the matrix is a consequence of proteolytic cleavage(s) of LTBP.

scholarly journals Epithelium-dependent extracellular matrix synthesis in transforming growth factor-beta 1-growth-inhibited mouse mammary gland.

1990 ◽  
Vol 110 (6) ◽  
pp. 2209-2219 ◽  
Author(s):  
G B Silberstein ◽  
P Strickland ◽  
S Coleman ◽  
C W Daniel
Keyword(s):  
Extracellular Matrix ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Messenger Rna ◽  
Transforming Growth Factor ◽  
Type I ◽  
Tgf Beta ◽  
Matrix Synthesis ◽  
The Matrix ◽  
Growth Factor Beta

Exogenous transforming growth factor beta (TGF-beta 1) was shown in earlier studies to reversibly inhibit mouse mammary ductal growth. Using small plastic implants to treat regions of developing mammary glands in situ, we now report that TGF-beta 1 growth inhibition is associated with an ectopic accumulation of type I collagen messenger RNA and protein, as well as the glycosaminoglycan, chondroitin sulfate. Both macromolecules are normal components of the ductal extracellular matrix, which, under the influence of exogenous TGF-beta 1, became unusually concentrated immediately adjacent to the epithelial cells at the tip of the ductal growth points, the end buds. Stimulation of extracellular matrix was confined to aggregations of connective tissue cells around affected end buds and was not present around the TGF-beta 1 implants themselves, indicating that the matrix effect was epithelium dependent. Ectopic matrix synthesis was specific for TGF-beta 1 insofar as it was absent at ducts treated with other growth inhibitors, or at ducts undergoing normal involution in response to endogenous regulatory processes. These findings are consistent with the matrix-stimulating properties of TGF-beta 1 reported for other systems, but differ in their strict dependence upon epithelium. A possible role for endogenous TGF-beta 1 in modulating a mammary epithelium-stroma interaction is suggested.

scholarly journals Latent transforming growth factor-beta 1 and its binding protein are components of extracellular matrix microfibrils.

1996 ◽  
Vol 44 (8) ◽  
pp. 875-889 ◽  
Author(s):  
J Taipale ◽  
J Saharinen ◽  
K Hedman ◽  
J Keski-Oja
Keyword(s):  
Extracellular Matrix ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Binding Protein ◽  
Human Fibroblasts ◽  
Tgf Beta ◽  
Growth Factor Beta ◽  
Cellular Fibronectin

We studied the localization of latent transforming growth factor-beta 1 (TGF-beta 1) and its binding protein (LTBP-1) in the extracellular matrix of cultured human fibroblasts by immunofluorescence and immunoelectron microscopy. Immunofluorescence of confluent fibroblast cultures indicated that LTBP-1 localizes to extracellular fibrillar structures resembling fibronectin-collagen matrix. Similar fibrillar structures were detected in cells stained with antibodies specific for TGF-beta 1 propeptide (beta 1-LAP). Both LTBP-1 and beta 1-LAP colocalized with fibronectin in double immunofluorescence analysis. These fibrillar structures were resistant to extraction with sodium deoxycholate, which is further evidence that LTBP-1 and large latent TGF-beta 1 complexes are integral components of the extracellular matrix. SV-40-transformed human fibroblasts lacked extracellular LTBP-1 fibers. EM analysis revealed approximately 10-nm-thick microfibrils that were labeled by anti-LTBP at 90-140-nm intervals. In addition, LTBP-1 was found in structures that were heavily labeled for fibronectin. The accumulation of LTBP-1 in the fibronectin matrix could be reconstituted in vitro. When isolated matrix components were immobilized on nitrocellulose and incubated with fibroblast conditioned medium, LTBP-1 from the medium associated with cellular fibronectin but not with heparan or chondroitin sulfate, vitronectin, tenascin, laminin, or collagen I or IV. The association of LTBP-1 with cellular fibronectin was abolished by treatment of the medium with plasmin, which cleaves LTBP-1 and inhibits its assembly to matrix. The present results indicate that latent TGF-beta 1 complexes are components of the extracellular matrix and suggest that alterations of the pericellular matrix could result in aberrant TGF-beta signaling.

scholarly journals Production of monoclonal antibodies that detect Hodgkin's high molecular weight transforming growth factor-beta

Blood ◽  
1990 ◽  
Vol 75 (12) ◽  
pp. 2434-2437
Author(s):  
SR Newcom ◽  
LH Muth ◽  
ET Parker
Keyword(s):  
Molecular Weight ◽  
Monoclonal Antibodies ◽  
Growth Factor ◽  
High Molecular Weight ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Antigenic Determinants ◽  
Enzyme Linked Immunosorbent Assay ◽  
Tgf Beta ◽  
Growth Factor Beta

High molecular weight transforming growth factor-beta (TGF beta) is a physiologically active TGF secreted by nodular sclerosing Reed- Sternberg cells. Five monoclonal murine antibodies were prepared that distinguished Hodgkin's TGF beta from platelet-derived TGF beta using an enzyme-linked immunosorbent assay, neutralization of biologic activity, and Western blotting. These monoclonal antibodies directed at unique antigenic determinants (epitopes) of Hodgkin's TGF beta will allow further characterization of the role of Hodgkin's TGF beta in Hodgkin's disease and related entities.

The emerging role of transforming growth factor-beta in kidney diseases

1994 ◽  
Vol 266 (6) ◽  
pp. F829-F842 ◽  
Author(s):  
K. Sharma ◽  
F. N. Ziyadeh
Keyword(s):  
Extracellular Matrix ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Cellular Response ◽  
Transforming Growth Factor ◽  
The Body ◽  
Special Focus ◽  
Tgf Beta ◽  
Growth Factor Beta

Transforming growth factor-beta (TGF-beta) is a prototypical multifunctional cytokine, with growth being only one of its many functions. Its receptors and actions are germane to almost every cell in the body involved in tissue injury and repair, and its effects are best understood in the context of a cellular response to a changing environment. The broad areas in which TGF-beta plays a crucial role include cell proliferation and extracellular matrix production. TGF-beta is a key regulatory molecule in the control of the activity of fibroblasts and has been implicated in several disease states characterized by excessive fibrosis. In the kidney, TGF-beta promotes tubuloepithelial cell hypertrophy and regulates the glomerular production of almost every known molecule of the extracellular matrix, including collagens, fibronectin, tenascin, and proteoglycans, as well as the integrins that are the receptors for these molecules. Furthermore, TGF-beta blocks the destruction of newly synthesized extracellular matrix by upregulating the synthesis of protease inhibitors and downregulating the synthesis of matrix-degrading proteases such as stromelysin and collagenase. As will be discussed, there is a strong body of in vitro and in vivo evidence suggesting that persistent overproduction of TGF-beta 1 in glomeruli after the acute inflammatory stage of glomerulonephritis causes glomerulosclerosis. TGF-beta may also be important in a variety of other chronic renal disorders characterized by hypertrophy and sclerosis, such as diabetic nephropathy. In this review we will attempt to offer a basic understanding of the cellular and molecular biology of TGF-beta and its receptors, with special focus on the role of the TGF-beta system in the kidney during development, growth, and disease.

scholarly journals Production of monoclonal antibodies that detect Hodgkin's high molecular weight transforming growth factor-beta

Blood ◽  
1990 ◽  
Vol 75 (12) ◽  
pp. 2434-2437 ◽  
Author(s):  
SR Newcom ◽  
LH Muth ◽  
ET Parker
Keyword(s):  
Molecular Weight ◽  
Monoclonal Antibodies ◽  
Growth Factor ◽  
High Molecular Weight ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Antigenic Determinants ◽  
Enzyme Linked Immunosorbent Assay ◽  
Tgf Beta ◽  
Growth Factor Beta

Abstract High molecular weight transforming growth factor-beta (TGF beta) is a physiologically active TGF secreted by nodular sclerosing Reed- Sternberg cells. Five monoclonal murine antibodies were prepared that distinguished Hodgkin's TGF beta from platelet-derived TGF beta using an enzyme-linked immunosorbent assay, neutralization of biologic activity, and Western blotting. These monoclonal antibodies directed at unique antigenic determinants (epitopes) of Hodgkin's TGF beta will allow further characterization of the role of Hodgkin's TGF beta in Hodgkin's disease and related entities.

scholarly journals Bovine latent transforming growth factor beta 1-binding protein 2: molecular cloning, identification of tissue isoforms, and immunolocalization to elastin-associated microfibrils.

1995 ◽  
Vol 15 (12) ◽  
pp. 6932-6942 ◽  
Author(s):  
M A Gibson ◽  
G Hatzinikolas ◽  
E C Davis ◽  
E Baker ◽  
G R Sutherland ◽  
...  
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Binding Protein ◽  
Elastic Tissue ◽  
Tgf Beta ◽  
Fibrillin 1 ◽  
Growth Factor Beta ◽  
Nuchal Ligament ◽  
Cysteine Motifs

Monoclonal antibodies to fibrillin 1 (MP340), a component of elastin-associated microfibrils, were used to screen cDNA libraries made from bovine nuchal ligament mRNA. One of the selected clones (cL9; 1.2 kb) hybridized on Northern (RNA) blotting with nuchal ligament mRNA to two abundant mRNAs of 9.0 and 7.5 kb, which were clearly distinct from fibrillin mRNA (10 kb). Further library screening and later reverse transcription PCR by the rapid amplification of cDNA ends (RACE) technique resulted in the isolation of additional overlapping cDNAs corresponding to about 6.7 kb of the mRNA. The encoded protein exhibited sequence similarity of around 80% with a recently identified human protein named latent transforming growth factor beta 1 (TGF-beta 1)-binding protein 2 (LTBP-2), indicating that the new protein was bovine LTBP-2. This was confirmed by the specific localization of bovine LTBP-2 cDNA probes to human chromosome 14q24.3, which is the locus of the human LTBP-2 gene. The domain structure of bovine LTBP-2 is very similar to that of the human LTBP-2, containing 20 examples of 6-cysteine epidermal growth factor-like repeats, 16 of which have the consensus sequence for calcium binding, together with 4 examples of 8-cysteine motifs characteristic of fibrillins and LTBP-1. A 4-cysteine sequence which is unique to bovine LTBP-2 and which has similarity to the 8-cysteine motifs was also present. Antibodies raised to two unique bovine LTBP-2 peptides specifically localized in tissue sections to the elastin-associated microfibrils, indicating that LTBP-2 is closely associated with these structures. Immunoblotting experiments identified putative LTBP-2 isoforms as a 260-kDa species released into the medium by cultured elastic tissue cells and as larger 290- and 310-kDa species in tissue extracts. A major proportion of tissue-derived LTBP-2 required treatment with 6 M guanidine for solubilization, indicating that the protein was strongly bound to the microfibrils. Most of the guanidine-solubilized LTBP-2 appeared to be monomeric, indicating that it was not involved in disulfide-bonded aggregation either with itself or with latent TGF-beta. Additional LTBP-2 was resistant to solubilization with 6 M guanidine but was readily extracted with a reductive saline solution. This treatment is relatively specific for solubilization of microfibrillar constituents including fibrillin 1 and microfibril-associated glycoprotein. Therefore, it can be inferred that some LTBP-2 is bound covalently to the microfibrils by reducible disulfide linkages. The evidence suggests that LTBP-2 has a direct role in elastic fiber structure and assembly which may be independent of its growth factor-binding properties. Thus, LTBP-2 appears to share functional characteristics with both LTBP-1 and fibrillins.

scholarly journals Transforming growth factor-beta 1 modulates basic fibroblast growth factor-induced proteolytic and angiogenic properties of endothelial cells in vitro.

1990 ◽  
Vol 111 (2) ◽  
pp. 743-755 ◽  
Author(s):  
M S Pepper ◽  
D Belin ◽  
R Montesano ◽  
L Orci ◽  
J D Vassalli
Keyword(s):  
Extracellular Matrix ◽  
Endothelial Cells ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Tgf Beta ◽  
Lumen Formation ◽  
Growth Factor Beta ◽  
Pai 1

Tightly controlled proteolytic degradation of the extracellular matrix by invading microvascular endothelial cells is believed to be a necessary component of the angiogenic process. We have previously demonstrated the induction of plasminogen activators (PAs) in bovine microvascular endothelial (BME) cells by three agents that induce angiogenesis in vitro: basic FGF (bFGF), PMA, and sodium orthovanadate. Surprisingly, we find that these agents also induce plasminogen activator inhibitor-1 (PAI-1) activity and mRNA in BME cells. We also find that transforming growth factor-beta 1 (TGF-beta 1), which in vitro modulates a number of endothelial cell functions relevant to angiogenesis, also increases both PAI-1 and urokinase-type PA (u-PA) mRNA. Thus, production of both proteases and protease inhibitors is increased by angiogenic agents and TGF-beta 1. However, the kinetics and amplitude of PAI-1 and u-PA mRNA induction by these agents are strikingly different. We have used the ratio of u-PA:PAI-1 mRNA levels as an indicator of proteolytic balance. This ratio is tilted towards enhanced proteolysis in response to bFGF, towards antiproteolysis in response to TGF-beta 1, and is similar to that in untreated cultures when the two agents are added simultaneously. Using an in vitro angiogenesis assay in three-dimensional fibrin gels, we find that TGF-beta 1 inhibits the bFGF-induced formation of tube-like structures, resulting in the formation of solid endothelial cell cords within the superficial parts of the gel. These results suggest that a net positive proteolytic balance is required for capillary lumen formation. A novel perspective is provided on the relationship between extracellular matrix invasion, lumen formation, and net proteolytic balance, thereby reflecting the interplay between angiogenesis-modulating cytokines such as bFGF and TGF-beta 1.

scholarly journals Transforming growth factor-beta (TGF-beta) isoforms in rat liver regeneration: messenger RNA expression and activation of latent TGF-beta.

1991 ◽  
Vol 2 (7) ◽  
pp. 535-548 ◽  
Author(s):  
S B Jakowlew ◽  
J E Mead ◽  
D Danielpour ◽  
J Wu ◽  
A B Roberts ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Growth Factor ◽  
Liver Regeneration ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Enzyme Linked Immunosorbent Assay ◽  
Regenerating Liver ◽  
Tgf Beta ◽  
Extracellular Matrix Components ◽  
Growth Factor Beta

Expression of transforming growth factor-beta s (TGF-beta s) 1-3 was studied in normal liver and during liver regeneration after partial hepatectomy in the rat to determine whether each of these isoforms might be involved in hepatocyte growth in vivo. Expression of the mRNAs for all three TGF-beta isoforms increases in the regenerating liver. In addition, the levels of expression of the mRNAs for several extracellular matrix proteins, including fibronectin, vitronectin, laminin, and collagen, also increase in the regenerating liver. Immunohistochemical staining analysis shows a similar distribution of all three TGF-beta s in normal and regenerating liver; however, in both tissues, the level of expression of TGF-beta 1 is 8- to 10-fold higher than that of TGF-beta 2 as determined by sandwich enzyme-linked immunosorbent assay. Expression of all three TGF-beta mRNAs is restricted to liver nonparenchymal cells. Although hepatocytes from normal and regenerating livers do not synthesize TGF-beta, they are sensitive to inhibition of growth by all three TGF-beta isoforms. Hepatocytes from regenerating livers are capable of activating latent TGF-beta 1 complexes in vitro, whereas normal hepatocytes are not. The different TGF-beta isoforms may function in an inhibitory paracrine mechanism that is activated during liver regeneration and may also regulate the synthesis of extracellular matrix components in the regenerating liver.

scholarly journals Macrophage production of transforming growth factor beta and fibroblast collagen synthesis in chronic pulmonary inflammation.

1989 ◽  
Vol 170 (3) ◽  
pp. 727-737 ◽  
Author(s):  
N Khalil ◽  
O Bereznay ◽  
M Sporn ◽  
A H Greenberg
Keyword(s):  
Extracellular Matrix ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Collagen Synthesis ◽  
Transforming Growth Factor ◽  
Pulmonary Inflammation ◽  
Late Phase ◽  
Primary Role ◽  
Tgf Beta ◽  
Growth Factor Beta

A rat model of bleomycin-induced pulmonary inflammation and fibrosis was used to examine the relationship between collagen synthesis and transforming growth factor beta (TGF-beta) production, and cellular distribution. Total lung TGF-beta was elevated within 2 h of intratracheal bleomycin administration and peaked 7 d later at levels 30-fold higher than controls. This was followed by a gradual decline with lower but persistent levels of production in the late phase of the response between 21 and 28 d later. The peak TGF-beta levels preceded the maximum collagen and noncollagen protein synthesis measured by [3H]proline incorporation into lung fibroblast explants of bleomycin-treated rats. The pattern of immunohistochemical staining localized TGF-beta initially in the cytoplasm of bronchiolar epithelium cells and subepithelial extracellular matrix. The peak of lung TGF-beta levels at 7 d coincided with intense TGF-beta staining of macrophages dispersed in the alveolar interstitium and in organized clusters. Later in the course of the response. TGF-beta was primarily associated with extracellular matrix in regions of increased cellularity and tissue repair, and coincided with the maximum fibroblast collagen synthesis. This temporal and spatial relationship between collagen production and TGF-beta production by macrophages suggests an important if not primary role for TGF-beta in the pathogenesis of the pulmonary fibrosis.

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