Showing papers by "Kathleen C. Flanders published in 1990"
TL;DR: The colocalization of intracellular staining by anti-LC with in situ hybridization of TGF beta 1 mRNA in the luminal and glandular epithelia on days 1-4 of pregnancy indicates that the epithelial cells are the primary sites of T GF beta 1 synthesis during the preimplantation period.
Abstract: Immunohistochemistry and in situ and Northern blot hybridization were employed to determine temporal and spatial expression of transforming growth factor-beta 1 (TGF beta 1) in the mouse uterus during the periimplantation period. The polyclonal antisera anti-LC-(1-30) and anti-CC-(1-30), raised against two different preparations of a peptide corresponding to the amino-terminal 30 amino acids of TGF beta 1, were used for histochemical analyses because of their distinct staining patterns. Anti-LC shows intracellular staining, while staining by anti-CC is primarily extracellular. The colocalization of intracellular staining by anti-LC with in situ hybridization of TGF beta 1 mRNA in the luminal and glandular epithelia on days 1-4 of pregnancy (day 1 = vaginal plug) indicates that the epithelial cells are the primary sites of TGF beta 1 synthesis during the preimplantation period. On the other hand, staining of the extracellular matrix of the stroma by anti-CC during this period suggests an active accumulation of TGF-beta 1 that is synthesized in and secreted from the epithelia. While intracellular staining and accumulation of TGF-beta 1 mRNA in the epithelia were clearly evident on days 1-4, the extracellular staining showed temporal fluctuations. The clear extracellular staining of the stroma that was observed on day 1 was absent on day 2; moderate staining was again visualized in the stroma on day 3 and was markedly increased on day 4.(ABSTRACT TRUNCATED AT 250 WORDS)
237 citations
TL;DR: The results indicate colocalization of TGF-beta 1 expression and that of matrix proteins in the developing lung when branching morphogenesis (cleft formation) and tissue stabilization occur, and suggests a direct participation of the growth factor in the development of the basic architecture of the lung.
Abstract: The possible in vivo role of TGF-beta 1 in regulating various proteins of the extracellular matrix, including fibronectin, collagen I and III, and glycosaminoglycans, was examined by immunohistochemical methods during critical stages of lung morphogenesis in the 11- to 18-day-old mouse embryo. Sections of Bouin-fixed, paraffin-embedded whole embryos were exposed to polyclonal antibodies specific to synthetic peptides present in the precursor part of TGF-beta 1 (pro-TGF-beta 1), in the processed TGF-beta 1 (antibody CC), collagen I and III, fibronectin, followed by the PAP or ABC technique to visualize the location of the antibody. GAG were stained with Alcian Blue 8GX. Our results indicate colocalization of TGF-beta 1 expression and that of matrix proteins in the developing lung when branching morphogenesis (cleft formation) and tissue stabilization occur. The presence of TGF-beta 1 at the epithelial-mesenchymal interfaces of stalks and clefts at a time when matrix proteins can first be visualized in these areas, suggests a direct participation of the growth factor in the development of the basic architecture of the lung.
221 citations
TL;DR: The ability of TGF-β to improve and/or accelerate tissue repair has been studied extensively in a variety of animal models of both normal and impaired healing.
216 citations
TL;DR: Mechanistically, TGF-beta s act to control gene expression of their target cells, many of their actions converging on a complex, multifaceted scheme of control of matrix proteins and their interactions with cells; these effects on matrix are thought to mediate many of the effects of TGF -beta on development.
Abstract: Transforming growth factors-beta (TGF-beta) are 25 kilodalton (kDa) homodimeric peptides with multifunctional actions controlling the growth, differentiation and function of a broad range of target cells of both epithelial and mesenchymal derivation. They are expressed early in embryogenesis and their tissue-specific and developmentally dependent expression is strongly suggestive of an essential role in particular morphogenetic and histogenetic events. Five distinct TGF-beta s have been characterized so far, with 65-80% homology to each other. By using both molecular biological and immunohistochemical techniques, we are currently attempting to define specific sites of expression of the different TGF-beta s and to determine whether TGF-beta s 1-5 might have unique functions in development and in the mature organism. Comparative study of the promoter regions for the different TGF-beta s and for any particular TGF-beta in different species is also underway. Mechanistically, TGF-beta s act to control gene expression of their target cells, many of their actions converging on a complex, multifaceted scheme of control of matrix proteins and their interactions with cells; these effects on matrix are thought to mediate many of the effects of TGF-beta on development.
184 citations
TL;DR: None of the TGF-β2 peptide antibodies was able to block receptor binding of either TGF -β1 or 2, and both anti-P 50–75(2) andAnti-P 79–108 (2) specifically immunoprecipitated TGF,β2 under reducing conditions only.
Abstract: Polyclonal antibodies have been raised to synthetic peptides corresponding to several regions of transforming growth factor-β2 (TGF-β2). All antisera were tested for their ability to react with either the native or reduced forms of both TGF-β1 and TGF-β2 in enzyme-linked immunosorbent assays, Western blots, and immunoprecipitation assays. On Western blots, antisera raised to a peptide corresponding to residues 50–75 of TGF-β2 specifically detected 5 ng TGF-β2, while antisera raised to regions 1–30 and 79–108 cross-reacted with TGF-β1. Anti-P 50–75(2) also localized TGF-β2 in murine placenta in immunohistochemical studies. In immunoprecipitation assays with either iodinated TGF-βs or with media conditioned by cells labeled with [35S]Jcysteine, both anti-P 50–75(2) and anti-P 79–108(2) specifically immunoprecipitated TGF-β2 under reducing conditions only, while anti-P 79–108(2) also reacted with TGF-β1. None of the TGF-β2 peptide antibodies was able to block receptor binding of either TGF-β1 or 2. A...
60 citations
01 Jan 1990
14 citations
TL;DR: Synthetic peptides corresponding to regions of human TGFP2 and chicken TGFP3 were coupled to bovine serum albumin through added amino and carboxyl terminal tyrosines and the conjugates were injected into rabbits to produce polyclonal antisera.
Abstract: Synthetic peptides corresponding to regions of human TGFP2 and chicken TGFP3 were coupled to bovine serum albumin through added amino and carboxyl terminal tyrosines and the conjugates were injected into rabbits to produce polyclonal antisera. The peptides and their homologies to other TGFBs are listed in TABLE 1. With the exception of anti-pre 127-146(2), antisera were affinity-purified by elution from a column of the appropriate peptide coupled to agarose. This treatment removed reactivity to bovine serum albumin, but reactivity to the peptide and to the appropriate TGFP was retained as determined in an ELISA assay. An antibody to amino acids 1-30 of TGFPl' was affinity-purified on a X F P l Sepharose column. On Western blots, anti-50-76(2) reacts with 2 ng of TGFP2, but not 100 ng of TGFPl. Anti-50-60(3) does not react with either 100 ng of TGF01 or 02, but does react with a 25 kD species present in media conditioned by NIH-3T3 cells transfected with a TGF03 expression vector. Antipre 81-lOO(3) recognizes a 90 kD species in this media. Both species recognized by the E F P 3 antibodies are half their molecular weight upon reduction and there is no reactivity with media from mock-transfected cells.
4 citations
Journal Article•
TL;DR: Proteoglycan-mediated binding and concentration of TGF-beta 1 in specific areas of the extracellular matrix may constitute a mechanism whereby the growth factor could be targeted to specific sites of action.
Abstract: We report here that extracellular TGF-beta 1 is associated exclusively with microfibrils of elastin which are present in the extracellular matrix of the inflamed articular joint of the rat. Inflammation was initiated by bacterial cell walls localized in the synovium following intraperitoneal injection of the bacterial components. This synovitis is associated with both destruction of connective tissue components and matrix deposition. The growth factor was localized by using a polyclonal antibody raised to a synthetic peptide corresponding to amino terminal 30 amino acids of TGF-beta 1 in conjunction with a gold-labeled secondary antibody. The results suggest a close association of TGF-beta 1 with proteoglycans which are known to be a major component of the microfibrils in elastin. Proteoglycan-mediated binding and concentration of TGF-beta 1 in specific areas of the extracellular matrix may constitute a mechanism whereby the growth factor could be targeted to specific sites of action.
2 citations
TL;DR: The present study investigated the synthesis and localization of TCFPl in fracture healing and found that its presence in fracture repair is dependent on the carrier and removal of canine coronavirus.
Abstract: Transforming growth factor-PI (TGFPI) modulates the proliferation and differentiation of various cell types and regulates the synthesis of extracellular matrix proteins. Although previous studies have shown that bone contains high levels of TGFPI, little is known about its presence in fracture repair. The present study was undertaken to investigate the synthesis and localization of TCFPl in fracture healing.
2 citations
TL;DR: TGF-beta 1 treatment had no effect on the growth rate of either cell type or on BPV-1 gene expression in the transformed cells, and neither the pattern nor intensity of TGF- beta 1 staining was affected by BPv-1 infection.
Abstract: There is substantial evidence to suggest that transforming growth factor-β (TGF-β) plays an important role in wound healing and tissue repair as well as in carcinogenesis. It has also been observed that naturally occurring bovine papillomavirus type 1 (BPV-l)-induced bovine fibropapillomas occur predominantly at traumatized sites of the body, suggesting that humoral factors released in wounds might be important for papillomavirus infection. We have therefore investigated the possible role of TGF-β1 in BPV-1 infections. Two anti-peptide antibodies which recognize different epitopes in the N-terminus of TGF-β1 were used to localize TGF-β1 in bovine fibropapillomas and normal bovine skin using im-munohistochemical methods. Staining by anti-LC(l-30) is intracellular in suprabasal keratinocytes of the epidermis as well as the hair follicles and sebaceous glands and correlates with known sites of TGF-β1 mRNA synthesis. Anti-CC(l-30) staining is extracellular in the immediately underlying dermis. Neither...