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P Calissano

Publications and source records attributed to P Calissano.

At least 55 records · Page 3Linked to original sources
PubMed1988

IFN-gamma facilitates NGF-induced neuronal differentiation in PC12 cells.

Natural or recombinant murine interferon-gamma causes a reversible arrest of proliferation of PC12 cells. Treatment with other antimitotics (AraC, colchicine, mitomycin C, hydroxyurea) or removal of serum, on the contrary, leads to mitotic arrest followed by cell death. IFN-gamma-treated PC12 cells respond more rapidly to NGF in terms of speed of neuronal outgrowth. On the other hand, NGF potentiates the action of IFN-gamma in stimulating the enzyme 2',5'-A synthetase which shifts from an average of 4.4-fold stimulation at 48 h with IFN-gamma alone to increments varying between 5- and 18-fold when PC12 cells are treated for 48 h with IFN-gamma and NGF. NGF alone, on the contrary, does not exert any detectable effect on this enzyme. From the findings we propose the use of a combined treatment of PC12 cells with NGF and IFN-gamma for a more rapid induction of neuronal differentiation.

Adrenal Gland Neoplasms↗
PubMed1988

Three distinct types of monoclonal antibodies after long-term immunization of rats with mouse nerve growth factor.

This article reports the results of a systematic investigation of the different types of antibodies produced in the course of a long-term immunization of rats with mouse nerve growth factor (NGF). We have characterized three types of monoclonal antibodies, namely: (1) antibodies that bind to NGF and inhibit its binding to target cells and its biological activity in culture (type A); (2) antibodies that bind to and precipitate NGF but do not inhibit its binding to target cells or its biological activity (type B); (3) antibodies that fail to recognize NGF itself, but inhibit nonetheless its binding to target cells (type C). These antibodies bind to an antigen present on NGF target cells and not on rat fibroblasts lacking NGF receptor. They appear thus to be antiidiotypic antibodies directed against the NGF receptor, developed as a consequence of the long-term immunization with NGF.

Animals↗
PubMed1988

Intracellular localization of nerve growth factor in PC12 cells. An immuno-gold electron microscopic approach.

Nerve growth factor (NGF) localization in the clonal cell line PC12 has been assessed with the immunocytochemical colloidal gold staining (IGS) method. Three distinct fixation and staining procedures have been adopted to avoid possible artifactual localizations and to better assess NGF intracellular targets. Colloidal gold particles are observed in the cytoplasm and also within the nuclear compartment, close to the nuclear envelope. Gold particles are also detectable, in aggregates or patches, in proximity of or in association with, cytoskeletal elements tentatively identified with microfilaments (MF) present in the growth cone and microtubules (MT) running in parallel within the neurites or present in the perikaryon. Neurofilaments (NF), on the contrary, were devoid of any NGF-antibody cross-reacting material detectable with colloidal gold staining. It is postulated that the association of NGF or NGF-receptor complexes with cytoskeletal elements is instrumental for the mechanism of action of NGF.

Animals↗
PubMed1986

Effect of nerve growth factor on glucose utilization and nucleotide content of pheochromocytoma cells (clone PC12).

The effect of nerve growth factor (NGF) on the utilization and fate of uniformly labeled 14C glucose and on the content of several pyridine and purine nucleotides has been tested in the clonal cell line PC12. After incubation for 72 h with NGF, PC12 cells exhibit a 2.7-fold increase in glucose utilization and a 4.7-fold increase in CO2 release. During the same incubation period, all the nucleotides tested (NAD+, AMP, GMP, UDP-glucose, UDP-galactose, UDP, ADP, GDP, UTP, CTP, ATP, and GTP) underwent significant increments, varying from a minimum of 27% for ADP to a maximum of 90-120% for AMP, GMP, UDP-glucose, and UDP-galactose. These findings are discussed in connection with the trophic and differentiative effects of NGF in PC12 cells, which, in the presence of this factor, shifted from a neoplastic to a neuronal-like cell population.

Adenosine Monophosphate↗
PubMed1985

Synthesis and content of a DNA-binding protein with lactic dehydrogenase activity are reduced by nerve growth factor in the neoplastic cell line PC12.

We have previously demonstrated that synthesis of a 34 kD protein having specific, high affinity for single-stranded DNA (34kD-ssb protein), is markedly inhibited by nerve growth factor (NGF) in the neoplastic clonal cell line PC12. We report here that total content as well as mRNA for this protein are progressively reduced in PC12 cells undergoing mitotic arrest and morphological differentiation induced by NGF. It is also shown that binding of the 34K-ssb protein to ssDNA is fully inhibited by NADH but not by NAD+ or by several other nucleotides. Enzymatic tests on the possible NADH/NAD+-dependent dehydrogenase activity of the 34K-ssb protein have demonstrated that it has lactic dehydrogenase activity (LDH) with a specific activity comparable to that of rabbit muscle. Furthermore, the 34K-ssb protein has the same peptide mapping as LDH purified from rat muscle. Antibodies directed against the 34K-ssb protein cross-react with the rabbit muscle enzyme and, vice versa, antibodies raised against rabbit LDH cross-react with the 34K-ssb protein. It is concluded that the 34K-ssb protein is identifiable with the type M of LDH, although possible differences in primary structure of the two proteins may have escaped the present studies. We hypothesize that interaction of the PC12 lactic dehydrogenase with ssDNA occurs also in vivo, as indicated by the findings reported in the accompanying paper, and may be modulated by the cellular content of NADH which, in turn, is related to energy metabolism.

Animals↗
PubMed1985

Nuclear localization of a lactic dehydrogenase with single-stranded DNA-binding properties.

In the preceding article [1] we identified the 34 kD single-stranded DNA-binding (ssb) protein, whose synthesis is inhibited in PC12 cells concomitantly with nerve growth factor (NGF)-induced mitotic arrest, with the enzyme lactic dehydrogenase (LDH-ssb protein). Localization studies performed with antibodies raised against the LDH-ssb protein demonstrate the presence of a pool of this protein in the nucleus of several cell types. The nuclear association of this protein is sensitive to DNase treatment of the cells and quantitative electron microscopy confirms that the LDH-ssb protein is located close to chromatin structures. These results point to a possible involvement of the LDH-ssb protein in some nuclear function(s).

Animals↗
PubMed1984

Nerve growth factor inhibits the synthesis of a single-stranded DNA binding protein in pheochromocytoma cells (clone PC12).

Arrest of mitosis and neurite outgrowth induced by nerve growth factor (NGF) in rat pheochromocytoma cells (clone PC12) is accompanied by a progressive inhibition of the synthesis of a protein that binds to single-stranded but not to double-stranded DNA. Time course experiments show that this inhibition is already apparent after a 2-day incubation with NGF and is maximum (85-95%) upon achievement of complete PC12 cell differentiation. Inhibition of the synthesis of this single-stranded DNA binding protein after 48 hr of incubation with NGF is potentiated by concomitant treatment of PC12 cells with antimitotic drugs acting at different levels of DNA replication. Purification on a preparative scale of this protein and analysis of its major physicochemical properties show that: (i) it constitutes 0.5% of total soluble proteins of naive PC12 cells; (ii) its molecular weight measured by NaDodSO4/PAGE is Mr 34,000 (sucrose gradient centrifugation under nondenaturing conditions yields a sedimentation coefficient s20,w of 8.1 S, indicating that the native protein is an oligomer); (iii) amino acid analysis demonstrates a preponderance of acidic over basic residues, while electrofocusing experiments show that it has an isoelectric point around 8.0; (iv) approximately 15% of the protein is phosphorylated in vivo. It is postulated that control of the synthesis of this protein is connected with activation of a differentiative program triggered by NGF in the PC12 neoplastic cell line at some step(s) of DNA activity.

Adrenal Gland Neoplasms↗
PubMed1983

Hidden receptors for nerve growth factor in PC12 cells.

The binding of nerve growth factor (NGF) to its receptors in PC12 cells was studied in two experimental conditions: (a) cell fixation with paraformaldehyde followed by permeabilization of the plasma membrane with methanol and (b) metabolic poisoning of living cells with sodium azide. Paraformaldehyde fixation of PC12 cells causes a 60-70% reduction of NGF binding capacity; the original binding capacity is restored following permeabilization with methanol. A kinetic analysis of NGF binding under these conditions reveals a single homogeneous population of receptors at variance with experiments performed in living cells where two kinetically distinct types of NGF receptors were demonstrated [Landreth, G. E. and Shooter, E. M. (1980) Proc. Natl Acad. Sci. USA, 77, 4751-4755; Schechter, A. L. and Bothwell, M. A. (1981) Cell, 24, 867-874]. Our results suggest that a proportion of the NGF receptors in PC12 cells is hidden, i.e. not available for binding to the ligand, and in a dynamic equilibrium with exposed receptors. The existence of hidden receptors is confirmed by treatment of PC12 cells with sodium azide, which causes a 50% reduction in NGF binding capacity and protection from trypsin digestion of the remaining pool of hidden receptors. The latter become exposed at the cell surface following removal of sodium azide. Our data provide an interpretation for the as yet unsatisfactorily explained data on NGF receptors.

Cell Line↗
PubMed1983

A macromolecular structure favouring microtubule assembly in NGF-differentiated pheochromocytoma cells (PC12).

Cellular extracts derived from pheochromocytoma cells (PC12-) inhibit the assembly of calf brain tubulin, while those derived from nerve growth factor-differentiated cells (PC12+) do not display this effect. Incubation with RNase abolishes the inhibition by PC12- extracts and reveals the presence of an activating effect exerted by PC12+ extracts. Activation of microtubule assembly is enhanced when extracts are prepared from PC12+ cells exposed for 1 day to 1.0 microM taxol and is abolished when PC12+ extracts are: (a) prepared from cells incubated for 1 day with 1 microM colchicine, (b) treated with the non-ionic detergent Nonidet P-40 or (c) centrifuged at 100 000 g instead of 80 000 g. 2D gel electrophoresis of the proteins of the 100 000 g pellet responsible for the activating effect (referred to as 100 K g pellet) reveals the presence of 100 K, 88 K and 32 K proteins which are markedly enriched in PC12+ extracts. The 88 K protein is further enriched in taxol-treated cells and markedly reduced in the same cells incubated with colchicine. A correlation between the differential protein composition of the 100 K g pellets and their effect on microtubule formation is postulated.

Adrenal Gland Neoplasms↗
PubMed1982

Effects of oral administration of nerve growth factor and of its antiserum on sympathetic ganglia of neonatal mice.

When NGF is orally administered to neonatal mice at the daily doses of 10 micrograms/animal for a 1-week period, a marked volume increase of para- and prevertebral sympathetic ganglia and neuronal hypertrophy are produced. Conversely oral administration of NGF antiserum to NGF for the same length of time, produces destruction of sympathetic nerve cells. The NGF effects correlate with the appearance in blood of this molecule in a biologically active form.

Administration, Oral↗
PubMed1982

Microtubules and microfilaments in fixed and permeabilized cells are selectively decorated by nerve growth factor.

A specific antibody against nerve growth factor (NGF) and indirect immunofluorescence microscopy have been used to follow the in vitro binding of NGF to cells made permeable to large molecules. All cells tested, both target (sensory neurons and PCI2 cells) and nontarget (3T3, BKH 2I, C6 glioma cells), revealed a decoration of cytoskeletal structures which on the basis of their form, reactivity with antibodies, and sensitivity to specific drugs may be identified as microtubules (MTs) and microfilaments (MFs). The decoration of either structure depends on the fixation and permeabilization conditions: MFs, in the form of stress fibers, are stained by NGF when the plasma membrane is permeabilized with methanol/acetone; MTs become intensely stained when the plasma membrane is solubilized with a nonionic detergent in the presence of a MT-stabilizing medium. The two procedures do not affect the staining of these structures with specific antibodies. Binding of 125I-labeled NGF to PCI2 cells was not competitively inhibited by a 100-fold excess of several positively charged proteins but it was markedly decreased in the presence of DNase I. 125I-Labeled NGF interacted with MTs and F-actin (fixed with paraformaldehyde) in a range of concentrations similar to that used for their cellular localization with NGF-anti-NGF. Our studies show that the specificity and affinity of NGF binding to MTs and MFs is in the range of that of antibodies against tubulin and actin. The possible relevance of these findings to the mechanism of action of NGF in target cells is discussed.

Actins↗
PubMed1981

Distribution of nerve growth factor in chick embryo sympathetic neurons in vitro.

The distribution of nerve growth factor (NGF) in chick embryo sympathetic neurons has been followed by two distinct procedures, that is, indirect immunofluorescence microscopy employing purified NGF antibodies and autoradiography after exposure of cells to [125I]NGF. This study shows that NGF bound to sympathetic neurons is not uniformly distributed but appears in spots over the surface of perikarya and along processes. If the same cells, after incubation with NGF and fixation, are treated with methanol-acetone to allow permeation of immunoglobulins across the plasma membrane, NGF antibody immunoreactive material is also found within the cytoplasm and notably in the paranuclear area only in sympathetic neurons. Analogous findings are obtained when sympathetic neurons are incubated in the presence of [125I]NGF, fixed, sectioned and processed for autoradiography. Also with this technique NGF appears to be localized in the cytoplasmic compartment and is found around the nucleus. These studies are discussed in connection with the results of similar experiments performed on a clonal line of NGF target cells known as PC12.

Animals↗
PubMed1980

Intracellular distribution of nerve growth factor in rat pheochromocytoma PC12 cells: evidence for a perinuclear and intranuclear location.

The distribution of nerve growth factor (NGF) in rat pheochromocytoma cells (clone PC12) has been studied with two different techniques: immunofluorescence and autoradiography. It was found that NGF is progressively internalized in the cytoplasmic compartment and eventually accumulates in the form of discrete dots around the nucleus. A fraction of the internalized NGF appears within the nucleoplasm, often contiguous with the nucleolus. It is suggested that cytoplasmic and perinuclear NGF may be be in contact with a pool of tubulin or actin-like proteins in their soluble or organized form and play a key role in the process of arrest of division and neurite growth.

Actins↗