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S R Goldring

Publications and source records attributed to S R Goldring.

At least 55 records · Page 3Linked to original sources
PubMed1992

Cloning, characterization, and expression of a human calcitonin receptor from an ovarian carcinoma cell line.

A human ovarian small cell carcinoma line (BIN-67) expresses abundant calcitonin (CT) receptors (CTR) (143,000 per cell) that are coupled, to adenylate cyclase. The dissociation constants (Kd) for the CTRs on these BIN-67 cells is approximately 0.42 nM for salmon CT and approximately 4.6 nM for human CT. To clone a human CTR (hCTR), a BIN-67 cDNA library was screened using a cDNA probe from a porcine renal CTR (pCTR) that we recently cloned. One positive clone of 3,588 bp was identified. Transfection of this cDNA into COS cells resulted in expression of receptors with high affinity for salmon CT (Kd = approximately 0.44 nM) and for human CT (Kd = approximately 5.4 nM). The expressed hCTR was coupled to adenylate cyclase. Northern analysis with the hCTR cDNA probe indicated a single transcript of approximately 4.2 kb. The cloned cDNA encodes a putative peptide of 490 amino acids with seven potential transmembrane domains. The amino acid sequence of the hCTR is 73% identical to the pCTR, although the hCTR contains an insert of 16 amino acids between transmembrane domain I and II. The structural differences may account for observed differences in binding affinity between the porcine renal and human ovarian CTRs. The CTRs are closely related to the receptors for parathyroid hormone-parathyroid hormone-related peptide and secretin; these receptors comprise a distinct family of G protein-coupled seven transmembrane domain receptors. Interestingly, the hCTR sequence is remotely related to the cAMP receptor of Dictyostelium discoideum (21% identical), but is not significantly related to other G protein-coupled receptor sequences now in the data bases.

Amino Acid Sequence↗
PubMed1991

Expression cloning of an adenylate cyclase-coupled calcitonin receptor.

A calcitonin receptor complementary DNA (cDNA) was cloned by expression of a cDNA library from a porcine kidney epithelial cell line in COS cells. The 482-amino acid receptor has high affinity for salmon calcitonin (dissociation constant Kd approximately 6 nM) and is functionally coupled to increases in intracellular cyclic adenosine monophosphate (cAMP). The receptor shows no sequence similarity to other reported G protein-coupled receptors but is homologous to the parathyroid hormone-parathyroid hormone-related peptide (PTH-PTHrP) receptor, indicating that the receptors for these hormones, which regulate calcium homeostasis, represent a new family of G protein-coupled receptors.

Adenylyl Cyclases↗
PubMed1991

An interleukin 1 beta point mutant demonstrates that jun/fos expression is not sufficient for fibroblast metalloproteinase expression.

Substitution of glycine for arginine at position 127 of the mature human interleukin 1 beta protein generates a mutant IL-1 beta protein (IL-1 beta R----G) which binds cellular IL-1 receptors with high affinity but fails to elicit significant proliferation of T-helper cells (Gehrke, L., Jobling, S. A., Paik, L. S. K., McDonald, B., Rosenwasser, L. J., and Auron, P. E. (1990) J. Biol. Chem. 265, 5922-5925). Although both IL-1 beta and the IL-1 beta R----G mutein stimulate transcription of fibroblast immediate early (fos and jun) and early (IL-1 beta and IL-6) genes, the IL-1 beta R----G mutein, in contrast to the wild-type IL-1 beta protein, induces minimal or no transcription of late genes such as procollagenase and prostromelysin. The effect of the naturally occurring IL-1 receptor antagonist protein (IL-1ra) on fibroblast transcription is distinct from that of the IL-1 beta R----G mutein, for the IL-1ra fails to stimulate not only late (procollagenase and prostromelysin) but also immediate early (fos and jun) gene expression. These data suggest that the IL-I beta R----G mutein triggers an incomplete or defective signal transduction cascade and demonstrate that fibroblast fos and jun expression is not necessarily accompanied by increased transcription of genes containing the AP-1 binding site. These data also suggest that at least two events are required for IL-1-mediated late gene induction in fibroblasts.

Blotting, Northern↗
PubMed1991

Cytokines and cell growth control.

Cellular proliferation in eukaryotic cells is associated with a highly organized sequence of events involving expression of growth-related genes. The growth regulatory cytokines such as platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), epidermal growth factor (EGF), and insulin-like growth factor (IGF-I) are thought to be responsible for initiating proliferation of fibroblasts and other connective tissue cells. The immunomodulatory cytokines, including interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma), are also known to modulate the growth response in nonimmune cells and regulate cellular metabolism by inducing expression of genes encoding biologically active molecules. While TGF-beta can induce anchorage-independent growth of nonneoplastic cells, it inhibits the proliferation of most normal cell types. Several of the cytokines that stimulate fibroblast proliferation may inhibit the growth of other cell types. Recent studies have also begun to assign specific roles to different cytokines in embryonic development and cellular differentiation. The growth response to some cytokines may be dependent upon the induction of other cytokines that then directly stimulate proliferation. Some cytokines may also modulate the responses induced by other cytokines by regulating receptor expression and other cellular events. Binding of cytokines to their specific membrane-associated receptors results in activation of signal transduction pathways, many of which involve phosphorylation of specific intercellular proteins. The final biological response is dependent ultimately on the induction and activation of trans-acting factors that regulate transcription by interacting with cis-acting DNA sequences in the target genes. Since many of these signaling and transcriptional events are common to distinct cytokines, many of which have different effects on proliferation in the same cell types, it is not clear how specificity is achieved in regulating the different biological responses.

Animals↗
PubMed1990

Infection of nonlymphoid cells by human immunodeficiency virus type 1 or type 2.

Human epithelial cells (L132) derived from embryonic lung and human lung fibroblasts (MRC5) were infected by human immunodeficiency virus type 1 (HIV-1) or type 2 (HIV-2). Surface CD4 protein was detected on these cells, and recombinant soluble CD4 (sCD4) blocked infection, indicating that HIV infection was mediated by the cell surface CD4 protein. In contrast, infection of human primary chondrocyte cells (C23), synovial cells (HSA), and foreskin fibroblasts (F13) was apparently independent of cell CD4-mediated mechanisms. Surface CD4 protein could not be detected on these cells, and sCD4 did not block the infection. F13 cells could be infected only by HIV-2, not by HIV-1, under our experimental conditions. In cells of mesenchymal orgin, viral production could be detected only after cocultivation with the human T-lymphoid H9 cells but not by conventional viral assays, including reverse transcriptase and p24 antigen assays in cell culture supernatant and immunofluorescence of host cells. Our DNA transfection studies indicated that this lack of detectable viral production was not due to the inefficient use of the HIV long terminal repeat or the Tat protein in these cells. These mesenchymal and epithelial cells were susceptible to HIV infection but differed in mechanism of virus entry compared with hematopoietic cells such as T lymphocytes. These observations may provide insights into clinical syndromes such as lung dysfunction in HIV-infected newborns and connective tissue disorders in HIV-infected adults.

Antigens, CD↗
PubMed1990

Heterogeneity in hormone responses and patterns of collagen synthesis in cloned dermal fibroblasts.

Fibroblasts cultured from normal human dermis are heterogeneous with respect to growth kinetics, synthetic function, and morphologic features. There are many examples of clonal heterogeneity in apparently homogeneous connective tissue cell populations, and it has been suggested that selection of cell populations with particular phenotypic features is the basis for the development of pathologic connective tissue changes in inflammatory disorders. In these studies we report characterization of the pattern of matrix biosynthesis and responses to hormones in cells cloned from normal human dermis. The results indicate that cloned dermal fibroblasts are heterogeneous with respect to synthesis of collagens as well as their responses to prostaglandin E2 and parathyroid hormone. Selective expansion of clonal populations with unique patterns of matrix synthesis and cell surface receptors could provide the basis for abnormal connective tissue remodeling in certain pathologic states.

Clone Cells↗
PubMed1990

Evaluation of connective tissue cell responses to orthopaedic implant materials.

We have developed an in vitro cell culture model to examine the interaction between connective tissue cells and orthopaedic implant biomaterials. Human connective tissue cells grown on different materials exhibit distinct responses in terms of attachment, morphology, proliferative capacity and matrix biosynthesis. Our results closely complement in vivo observations concerning biocompatibility and demonstrate the usefulness of this in vitro system for evaluating biomaterials. More importantly, this model can be used to define the specific cellular and biochemical processes that are responsible for the local tissue responses to orthopaedic implant materials.

Alloys↗
PubMed1990

Skeletal tissue response to cytokines.

Communication among individual cell types that populate connective tissues such as cartilage or bone is of critical importance in determining the phenotypic properties of these tissues under both physiologic and pathologic conditions. Cytokines, which may be defined as soluble products released from one cell that can modulate the activity of other cells, play a critical role in this process of cell communication. The introduction of molecular biologic techniques has permitted identification of specific cytokines previously characterized on the basis of biologic activities. Cloning and sequencing of these products have provided formal evidence for their existence and allowed identification of the full spectrum of their biologic activities. These results have established that individual cytokines may have multiple biologic activities and that multiple cytokines share common functional properties. Based on these results, the term "cytokine" has been used more generally to include products originally described as growth or differentiation factors, e.g., interleukins, monokines, or lymphokines. Cytokines have an important role in the initiation and control of skeletal tissue growth and development and in regulating bone remodeling in the adult organism. As in other connective tissues, these effects are mediated via paracrine, autocrine, and endocrine mechanisms. In skeletal tissues, cytokines may modulate the activity of resident cells by an additional mechanism. Factors produced locally within bone or arriving via the circulation are incorporated into the mineralized bone matrix, and their release during skeletal remodeling could provide the basis for coupling the activity of bone resorbing and forming cells. The principal cytokines that have been shown to affect skeletal tissues include factors previously described as monokines or lymphokines such as interleukin-1 (IL-1), tumor necrosis factors (TNF-alpha and TNF-beta), and interferon-gamma (IFN-gamma); the colony-stimulating factors; and the so-called growth and differentiation factors including transforming growth factors-alpha and -beta (TGF-alpha and TGF-beta), insulinlike growth factor-I (IGF-I), platelet-derived growth factor (PDGF), and fibroblast growth factor (FGF). Although the effects of the individual cytokines are diverse, it is possible to classify individual factors based on their effects on specific aspects of bone formation or resorption. Significant progress has been made recently toward elucidating the mechanisms of action of the cytokines. Binding studies using radiolabeled ligands have characterized the specific cell surface receptors and defined their distribution and properties among skeletal tissue cells. Various so-called signal transduction pathways have been implicated in mediating these effects...

Animals↗
PubMed1988

Cytokines.

During physiological and pathological skeletal remodelling, immune cells and stromal fibroblasts near active bone-forming and bone-resorbing surfaces might modulate the functions of skeletal tissue cells. Osteoblasts, osteoclasts and their progenitor cells are the probable direct targets of these effector cells (e.g. lymphocytes and monocytes) which act through direct contact or the release of soluble ligands (e.g. interleukin 1 or tumour necrosis factor, lymphotoxins, transforming growth factors). These cytokines bind to specific cellular receptors, resulting in changes in the form and function of the target bone cells and variable activation of genes coding for extracellular matrix proteins and proteinases which are responsible for remodelling the matrix. The synthesis and release of eicosanoids such as prostaglandins (e.g. PGE2) are frequent associated events. PGE2, in turn, affects several functions of the skeletal tissue cells as well as the lymphocytes and monocytes in their environment. The mesenchymal cells may also be induced to release ligands such as colony-stimulating factors, other cellular products or hormones resulting in a system of feedback and amplification loops. The cellular responses are thus subject to multiple controls not only determined by these ligands acting on their respective receptors but also by the pathways of signal transduction and how they, in turn, are influenced by interactions with molecules within the cells.

Animals↗
PubMed1988

Multinucleated cells elicited in response to implants of devitalized bone particles possess receptors for calcitonin.

The introduction into soft tissues of particulate materials resistant to digestion results in the induction of a "foreign-body giant-cell reaction." We have examined the relation between osteoclasts and foreign-body giant cells by comparing the tissue responses elicited by subcutaneous implants of devitalized, mineral-containing bone particles (BP), nonresorbable plastics such as polymethylmethacrylate (PMMA), or both. Implantation of BP results in the recruitment of multinucleated cells with features of in osso osteoclasts including tartrate-resistant acid phosphatase activity, contact-mediated resorption of BP, membrane specializations (ruffled borders and clear zones), and inhibition of resorption by calcitonin treatment of animals. In the present study, an autoradiographic technique employing 125I-salmon calcitonin was used to demonstrate the presence of receptors for this hormone on multinucleated cells from BP implants. In contrast, outgrowth cells from PMMA implants lacked calcitonin receptors. Demonstration of features of the osteoclastic phenotype in multinucleated cells elicited in response to BP supports the hypothesis that the mineralized matrix of bone may be a requirement for acquisition of the osteoclast phenotype.

Animals↗
PubMed1987

Human giant cell tumors of bone identification and characterization of cell types.

Cells cultured from human giant cell tumors of bone were characterized on the basis of morphological features, proliferative capacity, presence of granulocyte-monocyte antigens, receptors for skeletal hormones, and soluble cell products. Three major cell types were identified. One population consisted of mononuclear cells with fibroblastic morphology, which proliferated in culture and most likely represent the neoplastic element of the tumor. Phenotypically they resembled a connective tissue stromal cell. A second population of mononuclear cells lacked receptors for skeletal hormones and did not persist in culture. These cells were likely of monocyte-macrophage lineage. A third population of cells consisted of large multinucleated giant cells. These cells possessed phenotypic features of osteoclasts including receptors for calcitonin. Human giant cell tumors of bone are most likely a neoplasm of connective tissue stromal cells, which have the capacity to recruit and interact with multinucleated giant cells that exhibit phenotypic features of osteoclasts.

Antibodies, Monoclonal↗
PubMed1986

The adenosine 3':5'-cyclic monophosphate response to prostaglandin E2 is altered in U937 cells in association with maturational events induced by activated T lymphocytes and 1,25-dihydroxyvitamin D3.

Previous studies have shown that maturational changes can be induced in a human monocyte line, U937, by treatment with cellfree medium from lectin-stimulated cloned human T lymphocytes or the vitamin D metabolite, 1,25-dihydroxyvitamin D3 (1,25-[OH]2D3). Many of the maturational effects are accompanied by modification, new synthesis, or reorganization of cell surface membrane constituents, including proteins that function as receptors for ligands that modulate monocyte function. In the present studies, we examined the effects of monocyte differentiation on responsiveness to prostaglandin E2 (PGE)2. We found that the maturational effects of the lymphokine or 1,25[OH]2D3 were accompanied by a marked reduction in the PGE2-induced increase in cellular content of adenosine 3':5'-cyclic monophosphate (cAMP) and a shift in the dose-response curve consistent with a decrease in PGE2 receptor number or binding affinity. Incubation of cells with IFN-alpha or IFN-gamma produced by recombinant DNA technology did not influence PGE2 responsiveness, suggesting that the effects of the lymphokine were not mediated by these products. The absence of an effect on sodium fluoride- or forskolin-induced adenylate cyclase response in membranes prepared from treated cells suggests that the treatment conditions affect PGE2 receptor function rather than the adenylate cyclase enzyme complex. Changes in cell surface receptors for hormones such as PGE2 provide a potential mechanism for modulating the biologic activity of monocyte-macrophages during the process of cellular differentiation.

Adenylyl Cyclases↗
PubMed1986

Formation of a synovial-like membrane at the bone-cement interface. Its role in bone resorption and implant loosening after total hip replacement.

Histologic evaluation of tissue surrounding the loosened components after joint replacement reveals the presence of a synovial-like lining adjacent to the polymethyl methacrylate cement. The tissue is heavily infiltrated with particulate cement as well as polyethylene associated with a foreign body-type giant cell reaction. That this tissue response may be responsible for the bone lysis associated with loosening is suggested by the demonstration of high prostaglandin E2 levels and enhanced bone resorbing activity in the tissue culture medium of fragments from this membrane.

Arachidonic Acid↗
PubMed1986

Characterization of cells from human giant cell tumors of bone.

In vitro cell culture techniques were used to identify and characterize the individual cell types present in human giant cell tumors of bone. Three major cell types were identified based on morphologic characteristics, patterns of specific cell surface antigens, presence of receptors for hormones, and cell products. One population consisted of mononuclear cells that expressed monocyte-macrophage markers. These cells lacked receptors for skeletal hormones and did not persist in culture. Distinct from these cells was a population of mononuclear cells that proliferated in culture and most likely represented the neoplastic element of the tumor. These cells phenotypically resembled connective tissue stromal cells, i. e., they did not express macrophage surface antigens and they produced collagens (Types I and III). They also possessed receptors for parathyroid hormone. The final population of tumor cells consisted of multinucleated giant cells. These cells lacked monocyte-macrophage surface antigens and possessed receptors for calcitonin, a phenotypic marker for osteoclasts. These studies illustrate that in vitro cell culture techniques can be employed to identify and characterize the cell populations of tumors of skeletal tissues, and demonstrate the usefulness of these cell culture models for investigating the biology of bone tumors.

Adult↗
PubMed1986

Localized osteolysis in stable, non-septic total hip replacement.

We are reporting four cases of extensive, localized bone resorption adjacent to a rigidly anchored, cemented total hip replacement. None of these hips showed evidence of infection on clinical, bacteriological, or pathological evaluation. The tissue from the regions of osteolysis showed sheets of macrophages and foreign-body giant cells invading the femoral cortices. Abundant methylmethacrylate particulate debris was present in the tissues, but polyethylene wear debris was absent. The histological appearance of this tissue resembled that reported about loosened total hip implants with the exception of the synovial-like layer at the cement surface. The cases reported here show that aggressive bone lysis may occur around stable cemented total hip arthroplasties without the presence of sepsis or malignant disease.

Adult↗
PubMed1985

Differential effects of parathyroid hormone responsive cultured human cells on biological activity of parathyroid hormone and parathyroid hormone inhibitory analogues.

We have employed parathyroid hormone (PTH) responsive human cells cultured from dermis or giant cell tumors of bone (GT) to evaluate the biological properties of a newly developed in vivo PTH inhibitor, [Tyr34]bPTH-(7-34)-amide (PTH-Inh). Short periods of incubation of cells from dermis or GT with maximal stimulatory concentrations of PTH in the presence of increasing concentrations of PTH-Inh resulted in a dose-dependent inhibition of the adenosine cyclic 3',5'-phosphate (cAMP) response (Ki = 3 X 10(-7) M and 4.2 X 10(-7) M for GT and dermal cells, respectively). In both cell cultures, PTH-Inh alone did not increase cAMP levels, and in desensitization experiments, preincubation with PTH-Inh alone did not desensitize cells to PTH. Hence, the analogue displayed no agonist properties. Unexpectedly, when PTH-Inh was incubated with dermal cells in the presence of PTH, the PTH-Inh failed to block desensitization, suggesting a loss of biological effectiveness of the inhibitor. When medium containing PTH-Inh alone was removed from dermal cells and tested for inhibition of the acute PTH response in untreated cells, there was apparent loss of inhibitory efficacy (t1/2 = 20 h). In contrast, incubation of native PTH or bPTH-(1-34) with cells did not affect the biological activity of these ligands. Unlike the dermal cells, the PTH-Inh did block desensitization to PTH in GT, and there was no loss of inhibitor efficacy when medium containing PTH-Inh was incubated with GT (48 h) and then tested in untreated cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Biological Assay↗
PubMed1984

Photoaffinity labeling of parathyroid hormone receptors: comparison of receptors across species and target tissues and after desensitization to hormone.

Cells derived from human giant cell tumors of bone and fibroblasts derived from human neonatal foreskin respond to parathyroid hormone (PTH) by increasing the intracellular and extracellular levels of adenosine cyclic 3',5'-phosphate (cAMP). Using photoaffinity labeling methods, we examined these cells for the presence of a PTH receptor or a binding subunit of a receptor complex. A previously designed biologically active and photolabile radioligand analogue of PTH was reacted with these intact cells. After photolysis, the cells were extracted, and the proteins were denatured, reduced, and separated by electrophoresis on sodium dodecyl sulfate (Na-DodSO4)-polyacrylamide gels followed by autoradiography. A single membrane component, Mr 70 000, was labeled specifically in intact cells cultured from skeletal and dermal tissue. By mixing, in pairs, photolabeled proteins from (a) intact human cells derived from giant cell tumors of bone, (b) intact human fibroblasts, and (c) canine renal cortical membranes, the receptors (or their binding subunits) for PTH were compared directly and found to be identical in terms of molecular size (as determined by the migration position on NaDod-SO4-polyacrylamide gels) across species (dog and human) and target tissue (bone, skin, and kidney). Preincubation of cells cultured from giant cell tumors of bone with PTH resulted in loss of the PTH-induced cAMP response (desensitization). Preincubation with PTH was accompanied by a marked decrease in photoaffinity labeling of the PTH binding component and suggests that the loss of hormone response in cells preincubated with PTH was related to a decrease in the number or availability of PTH receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Affinity Labels↗