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Biomedical subjects

F Costanzo

Publications and source records attributed to F Costanzo.

At least 37 records · Page 2Linked to original sources
PubMed1994

A polymorphism (G-->A transition) in the -78 position of the apolipoprotein A-I promoter increases transcription efficiency.

AG-->A transition at -78 base pairs from the transcription start site of the apolipoprotein A-I (apoA-I) gene has been associated with increased apoA-I serum levels in humans. We report here that this mutation (G-->A) increases significantly (5-7-fold) the expression of a reporter gene fused to the apoA-I promoter in human liver and intestine cells. In addition, the presence of A at -78 base pairs from the transcription start site of the gene significantly decreases the binding affinity of a nuclear factor present in liver and intestine cells. We suggest that the reduced affinity of this factor increases the transcription efficiency of the promoter and explains why individuals carrying the A allele have high serum apoA-I levels.

Adenine↗
PubMed1994

Transcriptional regulation of the human H ferritin-encoding gene (FERH) in G418-treated cells: role of the B-box-binding factor.

We have analysed the molecular basis underlying the increase in ferritin heavy-chain mRNA (FERH) levels in cells exposed to the antibiotic Geneticin (G418). Transient transfection experiments demonstrate that this increase is paralleled by an enhanced transcription driven by the promoter (pFERH) for the human FERH gene, in which the most proximal promoter element (B-box) appears to play a key role. This region is conserved in human and rat, and binds an unknown factor. The DNA-protein complex composed of B-box-binding factor and its cis-element becomes more abundant in the G418-treated cells, as compared with the untreated ones.

Animals↗
PubMed1994

PCR analysis of the H ferritin multigene family reveals the existence of two classes of processed pseudogenes.

The human gene coding for the apoferritin H subunit belongs to a complex multigene family constituted by the expressed gene and by an undefined number of pseudogenes. We have used a strategy based on PCR to amplify specifically the H pseudogenes from a sample of human genomic DNA. With this approach, three new H pseudogenes have been cloned and characterized by DNA sequence analysis. In addition, we have identified a new type of pseudogene, the size of which (700 bp) is caused by multiple detection events in the putative coding region.

Base Sequence↗
PubMed1994

[Current trends in the treatment of giant nonparasitic cysts of the liver].

The authors report 10 cases of giant non-parasitic congenital cysts of the liver (7.7-25 cm in size). All the patients were symptomatic; preoperative ultrasonography was diagnostic in all cases allowing to discover the cyst. Six patients underwent partial resection of the cyst (in one of these a cystojejunostomy was performed), while atypical hepatic resection was performed in two cases, enucleation in one and left lobectomy in another case. No evidence of malignant degeneration was found in the histologic study of the specimens. No mortality nor morbidity were registered. All patients were followed up for 1-20 years and no recurrences were found. The authors point out that partial resection of the cyst is a safe operation with good immediate and long-term results.

Adolescent↗
PubMed1993

Passive immune protection by herpes simplex virus-specific monoclonal antibodies with different plaque development inhibition activity.

A series of herpes simplex viruses type 1 (HSV-1) neutralizing monoclonal antibodies (mAbs) with different plaque development inhibition (PDI) activity were tested for passive protection in mice. When virus was inoculated intracranially, mAbs with PDI activity were not more protective than mAbs without PDI activity. However, when virus was inoculated percutaneously, there was a trend indicating that neutralizing mAbs with PDI power were more active in protecting mice from the cutaneous lesion than mAbs without PDI power. The results are discussed in relation to the possible involvement of PDI activity in in vivo protection and to the fact that this mechanism of protection might operate in cutaneous, but not in nervous tissue.

Animals↗
PubMed1992

Promoter for the human ferritin heavy chain-encoding gene (FERH): structural and functional characterization.

We conducted a functional analysis of the promoter for the human ferritin heavy chain-encoding gene (pFERH) in HepG2 and HeLa cells. The activity of pFERH is equivalent in both cell types, despite their different ferritin (Fer) isotypes. Transfections of a series of 5'-deletion mutants indicate that pFERH activity is essentially dependent on two motifs. One of them, accounting for about 50% of the total transcriptional activity, is recognized by the RNA polymerase II transcription factor, Sp1, and the other by a low-affinity factor present in both the cell types analyzed.

Base Sequence↗
PubMed1990

Inhibition by anti-HLA class I mAb of IL-2 and IL-2 receptor synthesis in lymphocytes stimulated with PHA-P.

Inhibition by anti-HLA Class I monoclonal antibody (mAb) Q6/64 of phytohemagglutinin (PHA)-P-induced peripheral blood mononuclear cell (PMBC) proliferation is associated with a reduction of Tac expression and interleukin 2 (IL-2) secretion. To analyze the mechanism(s) underlying the latter phenomena, the Tac gene and IL-2 gene transcription was analyzed by a nuclear transcription assay. No synthesis of Tac and IL-2 mRNA was detected in PBMC stimulated with PHA-P in the presence of mAb Q6/64. In conjunction with our recently published data, these results indicate that the blocking by anti-HLA Class I mAb of PHA-P-induced PBMC proliferation reflects an inhibitory effect within the signal transduction pathway leading to transcriptional activation of IL-2 and IL-2 receptor genes.

Antibodies, Monoclonal↗
PubMed1990

Isolation of cDNA fragments hybridizing to rat brain-specific mRNAs.

A cDNA minilibrary in pUC18 has been generated from 3-month-old rat brains. Two hundred clones were randomly selected and sequenced. Comparison with a nucleic acid and protein data bank revealed a number of cDNA fragments not homologous to any published sequence. Northern blot analyses of some of these clones yielded 5 brain-specific cDNA fragments. The full-length cDNA for one of these clones has been isolated and completely sequenced. It corresponds to an mRNA of about 1,500 nucleotides, which is present in brain and, to a lesser extent, in heart and skeletal muscle. Its expression is developmentally regulated in the rat brain from 14-day embryos to 3-month-old adults. A very recent comparison with the EMBL nucleotide sequence data bank showed that this mRNA codes for a brain-specific snRNP-associated protein.

Aging↗
PubMed1989

Expression of genes of ferritin subunits in human hepatoma cell lines.

The expression of ferritin genes has been studied in two well differentiated hepatoma cell lines, HepG2 and Hep3B, and in an undifferentiated cell line, HepPLC/PRF/5. The steady-state level of the H and L ferritin subunit mRNAs is different in the three cell lines, being most abundant in the HepG2 and Hep3B cells. The efficiency of promotion of transcription of the H and L gene promoters is not correlated with the levels of the two transcripts; moreover the half-life of the H and L mRNAs varies among the hepatoma cells. The different level of ferritin mRNAs in differentiated and undifferentiated cells appears to be mainly due to a different stability of the transcripts.

Blotting, Northern↗
PubMed1989

Lack of a role of monocytes in the inhibition by monoclonal antibodies to monomorphic and polymorphic determinants of HLA class I antigens of PHA-P-induced peripheral blood mononuclear cell proliferation.

This study aimed at characterizing the mechanism(s) underlying the regulatory role of distinct determinants of HLA Class I antigens in PHA-P-induced T cell proliferation and the involvement of monocytes in this phenomenon. The anti-HLA-A2,A28 monoclonal antibodies (MoAb) CR11-351, the MoAb Q6/64 to a determinant restricted to the gene products of the I antigens HLA-B locus, and the MoAb CR10-215 and W6/32 to distinct monomorphic determinants of HLA Class I antigens were found to inhibit PHA-P-induced peripheral blood mononuclear cell (PBMC) proliferation in a dose-dependent fashion. The inhibition is specific and reflects neither inhibition of PHA-P binding to cells nor a toxic effect of the anti-HLA Class I MoAb. The latter differed in the concentration required to induce inhibition, in the influence of the concentration of PHA-P used as mitogen, in the differential effect on the donors used as a source of PBMC, and/or in the requirement of the Fc portion to induce inhibition. At variance with the information in the literature, the inhibitory effect of anti-HLA Class I MoAb on PHA-P-induced PBMC proliferation neither reflected their interaction with accessory cells nor was mediated by suppressor factors released by monocytes stimulated with PHA-P in the presence of anti-HLA Class I MoAb. Therefore, the regulatory role of HLA Class I antigens in T cell proliferation is not likely to be mediated by monocytes and/or factors released from them, but may reflect an involvement of these molecules in T cell activation pathways.

Antibodies, Monoclonal↗
PubMed1989

Inhibition of herpes simplex virus type 1 (HSV-1) plaque enlargement by neutralizing sera.

The inhibitory activity of neutralizing sera on Herpes simplex virus type 1 (HSV-1) plaque enlargement (PE) is easily detected using the S variant of low passage clinical isolates (Mannini-Palenzona et al., 1985b; Costanzo et al., 1986). The same sera show little or no activity on PE of the product of the S variant rapid in vitro conversion, the L variant, and laboratory strains HSV-1 (F) and (MP). No significant difference was found in the inhibitory activity of sera from healthy individuals with no history of recurrence and patients with recurrences.

Adult↗
PubMed1989

Proliferative pathways in CD1- CD3+ CD4+ CD8+ T-prolymphocytic leukemic cells: analysis with monoclonal antibodies and cytokines.

The antigenic profile and the proliferative pathways in leukemic cells from the patient TRT with T-prolymphocytic leukemia (T-PLL) were analyzed using monoclonal antibodies (MoAbs) and cytokines. T-PLL cells expressed the phenotype CD1- CD3+ CD4+ CD8+. Incubation with the differentiating agent phorbol-12-myristate-13-acetate markedly increased the percentage of cells with the CD4- CD8+ phenotype, suggesting that leukemic cells were already committed towards a differentiated element with the CD4- CD8+ phenotype. T-PLL cells were induced to proliferate by anti-CD2 MoAb 9-1 + 9.6 and by anti-CD3 MoAb OKT3. The two pathways exhibited normal functional interactions and were susceptible to modulation by anti-HLA class I MoAbs. These results indicate that regulation of cell proliferation was preserved to a significant extent in the T-PLL cells analyzed. At variance with normal resting T cells that require previous activation to proliferate when incubated with interleukin-1 (IL-1) or interleukin-2 (IL-2), T-PLL cells proliferated vigorously when incubated with either interleukin. Furthermore, T-PLL cells proliferated when incubated with immune interferon (IFN-gamma). The latter finding parallels the enhancement by IFN-gamma of the proliferative response of lectin-activated murine T lymphocytes. These results suggest that T-PLL cells, which express a high constitutive level of c-myc mRNA, may be in an activated state. The antigenic phenotype and the characteristics of the proliferative pathways of T-PLL cells from the patient TRT are compatible with the possibility that they may be derived from an intermediate thymocyte.

Antibodies, Monoclonal↗
PubMed1987

The transcriptional efficiency of clustered tRNA genes is affected by their position within the cluster.

The transcription of a mouse genomic segment containing four tRNA genes, coding for a tRNA(Ala), a tRNA(Ile), a tRNA(Pro) and a tRNA(Lys), has been studied in a HeLa cell extract, demonstrating that differences among their transcriptional efficiencies are evident using as templates either the natural cluster or an equimolecular mixture of the four isolated genes. Nevertheless, the structure of the cluster influences the transcriptional efficiency of the clustered genes. In fact, a cis-acting inhibitory sequence has been located at about 400 bp downstream of the tRNA(Pro) coding sequence. Moreover rearrangements of the reciprocal position of the various tRNA genes within the cluster results in significant changes in the transcriptional rates of the individual transcriptional units.

Animals↗
PubMed1986

Structure and in vitro transcription of tRNA gene clusters containing the primers of MuLV reverse transcriptase.

Three genes coding for mouse tRNAPro have been isolated from a genomic library and characterized both structurally and functionally. Two of these (tPro52 and tPro53) code for the tRNA primer of reverse transcriptase of MuLV. The third one (tPro51) shows several differences (mutations and deletions) that probably prevent the folding of the matured transcript into the cloverleaf structure, and is therefore a pseudogene. This pseudogene gives rise to a RNA transcription product in vitro. tPro52 is clustered with a tRNALys gene and with a tRNAAla gene, which is strongly homologous to the rat identifier repeated sequence. tPro53 is clustered with a tRNAAsp and a tRNAGly gene. Other tRNA-hybridizing sequences are present in the lambda clones that contain tPro51 and tPro53.

Anticodon↗
PubMed1986

Cloning of the gene coding for human L apoferritin.

A recently reported cDNA clone coding for human promyelocytic L apoferritin, shows some differences with a liver L apoferritin cDNA. We have investigated if these differences are due to the expression of different genes or to an alternative transcription of an unique gene. In this paper we report data suggesting that a single gene is mainly expressed in several tissues examined. This gene has been cloned and characterized. Its sequence shows three introns: the exon sequence is identical to that of cDNA clone isolated from human liver. A minimum of five related pseudogenes have been also analysed. One of them is a processed pseudogene interrupted by an intron-like fragment.

Amino Acid Sequence↗
PubMed1986

Structure of gene and pseudogenes of human apoferritin H.

Ferritin is composed of two subunits, H and L. cDNA's coding for these proteins from human liver (1,2,3), lymphocytes (4) and from the monocyte-like cell line U937 (5) have been cloned and sequenced. Southern blot analysis on total human DNA reveals that there are many DNA segments hybridizing to the apoferritin H and L cDNA probes (1,2,4,6). In view of the tissue heterogeneity of ferritin molecules (7,8), it appeared possible that apoferritin molecules could be coded by a family of genes differentially expressed in various tissues (1,2). In this paper we describe the cloning and sequencing of the gene coding for human apoferritin H. This gene has three introns; the exon sequence is identical to that of cDNA's isolated from human liver, lymphocytes, HeLa cells and endothelial cells. In addition we show that at least 15 intronless pseudogenes exist, with features suggesting that they were originated by reverse transcription and insertion. On the basis of these results we conclude that only one gene is responsible for the synthesis of the majority of apoferritin H mRNA in various tissues examined, and that probably all the other DNA segments hybridizing with apoferritin cDNA are pseudogenes.

Apoferritins↗
PubMed1986

Further characterization of virus obtained from herpes simplex virus type 1 recurrences and primary infections. Influence of the temperature of incubation upon glycoprotein synthesis and virus release. Brief report.

The virus contained in clinical isolates of herpes simplex virus type 1 (HSV-1) which have not undergone previous in vitro passages (new isolates) differs from HSV-1 prototype strains with respect to infected cell glycoprotein pattern, and, most probably efficiency of virus egress at 37 degrees C. The differences can be abolished by lowering the temperature of incubation to 33 degrees C. A few tissue culture passages cause the conversion of the original virus to a virus undistinguishable from HSV-1 prototype strains with respect to the parameters mentioned above.

Animals↗