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Biomedical subjects

V Pistoia

Publications and source records attributed to V Pistoia.

At least 55 records · Page 3Linked to original sources
PubMed1997

B-cell-derived granulocyte-colony stimulating factor (G-CSF).

Biologically active granulocyte-colony stimulating factor (G-CSF) was released spontaneously in culture by in vivo activated tonsillar B lymphocytes and, in particular, by the germinal center (GC) B-cell subset. In contrast, mantle zone B cells failed to produce the cytokine under any of the culture conditions tested. A CD40 monoclonal antibody (mAb), recombinant (r) IL4, and the combination of the CD40 mAb and rIL4 all increased G-CSF production by GC B cells. The augmentation of G-CSF release correlated with the increased survival of GC B cells. rG-CSF rescued GC B cells from apoptosis, suggesting that the cytokine may be utilized in autocrine and/or paracrine ways. Neoplastic B cells from follicular center cell lymphoma patients, which are the counterparts of normal GC B lymphocytes, also released G-CSF spontaneously in culture. In contrast, malignant B cells from a subset of chronic lymphocytic leukemia (CLL) patients had to be stimulated with Staphylococcus aureus Cowan I or CD40 mAb in combination with rIL4 or rIL2 to produce G-CSF in vitro. Some B-CLL cell suspensions were rescued from spontaneous apoptosis following culture in the presence of rG-CSF. Taken together, these studies provide the first demonstration that G-CSF (i) is produced by either normal or neoplastic human B lymphocytes and (ii) participates in the modulation of apoptosis of the same cells.

Antibodies, Monoclonal↗
PubMed1997

Synovial fluid T cell clones from oligoarticular juvenile arthritis patients display a prevalent Th1/Th0-type pattern of cytokine secretion irrespective of immunophenotype.

The aim of the present study was to investigate the patterns of cytokine production by T cell clones raised from in vivo activated synovial fluid (SF) mononuclear cells (MNC) of five patients with oligoarticular juvenile arthritis (JA). Freshly isolated SF T cells were cultured in vitro with low dose recombinant IL-2 and subsequently cloned by limiting dilution. Sixty-four clones were obtained from the five patients studied. Fifty-nine clones were TCR alpha/beta+, either CD4+ (n = 43) or CD8+ (n = 15). The remaining five clones were TCR gamma/delta+, CD4-, CD8-. Clone immunophenotypes differed in the individual patients. Forty-four T cell clones were stimulated with phytohaemagglutinin (PHA) and phorbol myristate acetate (PMA) and supernatants tested for the presence of IL-2, IL-4, IL-5 and interferon-gamma (IFN-gamma) by ELISA or bioassays. Cytokine mRNA accumulation was tested by reverse transcriptase-polymerase chain reaction (RT-PCR). Most of 44 clones tested released large amounts of IFN-gamma irrespective of the immunophenotype. Of these, 27 were classified as Th1-type and 17 as Th0-type based upon the IFN-gamma/IL-4 ratio in culture supernatants. Finally, when 10 representative T cell clones were tested for pro- and anti-inflammatory cytokines, gene expression by RT-PCR, all of them were found to express the granulocyte-macrophage colony-stimulating factor (GM-CSF), tumour necrosis factor-alpha (TNF-alpha), IL-10 and transforming growth factor-beta 1 (TGF-beta1) genes, and half of them IL-6 and IL-8 mRNA. In conclusion, T cell clones, that represent the progeny of in vivo activated SF T cells from oligoarticular JA patients, display heterogeneous immunophenotypes, but all share the ability to produce large amounts of IFN-gamma, with a predominant Th1/Th0 pattern. The expression of pro- and anti-inflammatory cytokine genes in these clones suggests that in vivo activated SF T cells modulate joint inflammation in a complex fashion.

Adolescent↗
PubMed1997

[Prenatal diagnosis of triploidy and trisomy 21 through fetal erythroblasts isolated from maternal blood].

BACKGROUND: A long-sought goal of medical genetics has been the development of prenatal diagnostic procedures that do not endanger the conceptus. The safety of noninvasive methods for prenatal diagnosis would be especially attractive because they could be extended to all pregnant women, regardless of their ages or histories. Noninvasive prenatal diagnosis for the entire population might be possible recovering fetal cells from maternal blood. For this purpose, we have studied fetal erythroblasts. MATERIALS AND METHODS: To evaluate the potential of the method for clinical use, we studied maternal blood samples from 11 women referred to us for prenatal diagnosis between 15 and 20 weeks of gestation. For simple and effective enrichment of fetal nucleated erythrocytes from peripheral maternal blood, we combined a triple density gradient and magnetic-activated cell sorting (MACS) of anti-CD71 transferrin receptor antibody labeled cells. The isolated cells were analysed by using dual-colour interphase fluorescent in situ hybridization (FISH) with X-, Y-, 18- and 21-specific DNA probes. RESULTS: Chromosomal abnormalities detected on enriched fetal cells include trisomy 21 and triploidy. CONCLUSIONS: Based on the current results it is suggested that the technique described here is a simple, fast, efficient and reliable method for non invasive prenatal diagnosis.

Down Syndrome↗
PubMed1996

Expression of MAGE-1, MAGE-3 and MART-1 genes in neuroblastoma.

The human MAGE-1, MAGE-3 and MART-1 genes code for antigens that are specifically recognized by cytolytic T lymphocytes in a MHC-restricted manner. The MAGE-1 and MAGE-3 genes are expressed in tumors of different histotypes but not in normal adult tissues (with the exception of testis), while the MART-1 gene appears to be selectively expressed in melanoma. MAGE-1, MAGE-3 and MART-1 antigens may therefore constitute useful targets for specific anti-tumor immunization of cancer patients. Here we have investigated the expression of MAGE-1, MAGE-3 and MART-1 in 11 neuroblastoma (NB) cell lines and 73 NB tumor masses. MAGE-1 and MAGE-3 transcripts were detected simultaneously in 36% of the cell lines and in 16% of tumor samples. The MAGE-1 gene was never expressed alone except in one tumor. In contrast, MAGE-3 mRNA was found in approximately 40% of the NB tumor samples in the absence of MAGE-1 mRNA. No expression of the MART-1 gene was observed in any cell line or tumor sample. No correlation was found between MAGE gene expression and clinical stage, event-free survival and presence or absence of N-myc amplification.

Antigens, Neoplasm↗
PubMed1996

Increase of metaiodobenzylguanidine uptake and intracellular half-life during differentiation of human neuroblastoma cells.

Iodine-labelled metaiodobenzylguanidine (MIBG) is a radiopharmaceutical used for diagnostic imaging and targeted radiotherapy of neuroendocrine tumors. We previously reported that the ability of a neuroblastoma (NB) cell line, LAN-5, to accumulate MIBG was powerfully stimulated by interferon-gamma (IFN-gamma), a well-known NB differentiation-promoting agent. To extend the above findings, we have investigated 5 NB cell lines for their ability to accumulate 125I-MIBG in basal conditions or after various combinations of differentiative stimuli. Our results show that association of IFN-gamma and tumor necrosis factor-alpha boosts MIBG uptake in the early times of incubation in LAN-5 and GI-LI-N cells, while both SK-N-SH and SK-N-BE(2)c cells are strongly stimulated by co-treatment with IFN-gamma and all-trans retinoic acid. Moreover, although only LAN-5 and GI-LI-N cells are sensitive to IFN-gamma alone, the combination of IFN-gamma and IFN-alpha causes a synergistic increase in MIBG uptake in all the NB cell lines tested. From experiments on MIBG release we conclude that no intracellular storage within specialized structures took place during differentiation. The observed enhancement in MIBG accumulation results from an increased uptake of the drug only. This conclusion was confirmed by analyzing MIBG-transporter gene expression, which was increased in cells subjected differentiative regimens. According to these findings, inducing differentiation of NB cells in vitro appears to improve their MIBG incorporation ability powerfully.

3-Iodobenzylguanidine↗
PubMed1996

Expression of granulocyte colony-stimulating factor and granulocyte colony-stimulating factor receptor genes in partially overlapping monoclonal B-cell populations from chronic lymphocytic leukemia patients.

B lymphocytes were purified from the peripheral blood of 30 B-cell chronic lymphocytic leukemia (B-CLL) patients and tested for the ability to produce granulocyte colony-stimulating factor (G-CSF) in vitro. Fifteen Staphylococcus aureus Cowan I (SAC)-stimulated, but not unstimulated, B-cell suspensions produced G-CSF in short-term cultures. Accordingly, G-CSF mRNA was detected only in SAC-stimulated B cells. Five CLL B-cell fractions that released G-CSF following exposure to SAC were also incubated with CD40 or anti-mu antibodies in the presence or absence of recombinant (r) interleukin-2 (IL-2) or IL-4. The 5 cell suspensions produced G-CSF only on culture with CD40 monoclonal antibody in combination with rIL-2 or rIL-4. CD5+ B lymphocytes, which represent the normal counterparts of most B-CLL proliferations, did not produce G-CSF under any of the above culture conditions. G-CSF produced by leukemic B lymphocytes was biologically active, because conditioned media of SAC-stimulated cells supported the in vitro growth of myeloid colonies from normal bone marrow progenitors. The colony stimulating activity of CLL B-cell supernatants was ascribed to both G-CSF and granulocyte-macrophage colony stimulating factor. G-CSF receptors (G-CSFRs) were detected on freshly isolated B lymphocytes from 7 of 11 B-CLL patients; 5 of these cell suspensions produced G-CSF in culture, whereas 2 did not. rG-CSF rescued 3 of the 7 G-CSFR+ cell fractions from spontaneous apoptosis but had no effect on their in vitro proliferation.

B-Lymphocytes↗
PubMed1996

Functional and molecular characterization of tumour-infiltrating lymphocytes and clones thereof from a major-histocompatibility-complex-negative human tumour: neuroblastoma.

Neuroblastoma (NB) is a major-histocompatibility-complex(MHC)-negative neuroectodermal tumour that is often infiltrated with lymphocytes. A detailed characterization of NB-associated tumour-infiltrating lymphocytes (TIL) has never been carried out. Here we have investigated the immunophenotype and the cytotoxic activities of TIL from nine and seven NB patients respectively. Furthermore, the T cell receptor (TcR) variability and the patterns of cytokine gene expression of fresh versus recombinant (r) interleukin (IL)-2-cultured TIL were studied in four NB cases. The results obtained showed the following: (1) freshly isolated TIL were comprised of a mixture of CD4+ and CD8+ T cells partially expressing HLA-DR and/or CD25. The CD4/CD8 ratio ranged from 0.5 to 5 in the different cases. Upon culture of TIL with rIL-2, an increased proportion of CD56+ and CD8+ lymphocytes was consistently observed; (2) IL-2-expanded TIL lysed natural-killer(NK)sensitive and lymphokine-activated-killer(LAK)-sensitive target cell lines; (3) reverse-transcriptase/polymerase-chain-reaction (RT-PCR) experiments showed that most TcR V beta genes were expressed both in fresh and in cultured TIL, suggesting that such cell populations were polyclonal; (4) interferon gamma, IL-4, IL-5, tumour necrosis factor (TNF) alpha, IL-8, IL-10 mRNA and, to a lesser extent, IL-2 mRNA were expressed by cultured TIL, as assessed by RT-PCR; the corresponding tumour samples consistently contained TNF alpha, IL-8 and IL-10 mRNA, whereas IL-2 and IFN gamma mRNA were faintly expressed in some NB tumours and IL-4 and IL-5 mRNA were never detected. A total of 90 clones were subsequently raised from IL-2-expanded TIL from six NB patients; 87/90 clones were of T cell lineage with a CD4+ or CD8+ immunophenotype, whereas the 3 remaining clones were of NK cell origin. Upon triggering of the CD3-TcR complex, 64% CD4+ and 77% CD8+ T cell clones killed the murine P815 mastocytoma cell line. Virtually no T cell clone lysed a LAK-sensitive NB cell line whereas 15% CD4+ and 17% CD8+ clones mediated NK-like activity against the K562 cell line. Finally, the patterns of cytokine production by CD4+ clones were roughly consistent with those of a T helper (TH) 1 profile and similar to those observed in CD8+ clones.

Base Sequence↗
PubMed1996

Serum p55 and p75 tumour necrosis factor receptors as markers of disease activity in juvenile chronic arthritis.

OBJECTIVE: To determine the expression of tumour necrosis factor alpha (TNF alpha) and its soluble receptors (p55 and p75) in the sera and synovial fluid of patients with juvenile chronic arthritis (JCA), and their correlation with disease activity parameters. METHODS: Ninety eight sera from 45 patients with JCA (14 systemic, 12 polyarticular, 19 pauciarticular), 20 sera from age matched healthy controls, and five synovial fluids from five antinuclear antibody (ANA) positive pauciarticular JCA patients were tested for the presence of TNF alpha, soluble TNF receptors p55 and p75 (sTNFRp55, sTNFRp75), and interleukin-6 (IL-6) by an enzyme amplified sensitivity immunoassay. Physician global estimate of disease activity, weekly fever score and joint score, C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and haemoglobin concentration were evaluated as parameters of disease activity. The expression of p55 and p75 on peripheral mononuclear cells (MNCs) from five patients with systemic JCA and synovial MNCs from five ANA positive patients with pauciarticular JCA was evaluated by flow cytometry. RESULTS: TNF alpha serum concentrations did not differ significantly between the patients with active JCA and the control group. No correlation was found between TNF alpha and parameters of disease activity, but both p55 and p75 showed a significant positive correlation with the physician global estimate of disease activity (p < 0.001), ESR (p < 0.001), CRP (p < 0.001), and serum concentrations of IL-6 (p < 0.001). Serum concentrations of haemoglobin correlated inversely with the concentrations of p55 and p75 (p < 0.001). Synovial lymphocytes selectively expressed the p75 surface receptor. CONCLUSIONS: sTNFRp55 and sTNFRp75 each represent a sensitive marker of disease activity in JCA. Their increased expression in biological fluids may support the hypothesis that TNF alpha has a role in the pathogenesis of JCA.

Adolescent↗
PubMed1996

Common variable immunodeficiency presenting in a girl as lung infiltrates and mediastinal adenopathies leading to severe "superior vena caval" syndrome.

Common variable immunodeficiency (CVID) is a primary immunodeficiency disorder characterized by decreased levels of circulating immunoglobulins (Ig) and increased susceptibility to infections. We describe the case of a girl, progressively developing CVID, whose first clinical manifestations were noninfectious diffuse pulmonary infiltrates and rapidly developing hilar and mediastinal lymphadenopathies causing a severe "superior vena caval syndrome". Histological evaluation of surgical samples showed follicular and paracortical hyperplasia of the lymph nodes and poorly organized, non-necrotizing, noninfectious, "reactive" granulomata in lymph nodes and pulmonary tissue. Daily treatment with azathioprine and prednisone induced resolution of the intrathoracic abnormalities but was associated with a progressive decrease of circulating IgG and IgA levels and natural killer (NK) lymphocytes that was not related to treatment. This case demonstrates that granulomatous inflammatory changes may be the first manifestations of common variable immunodeficiency, and that this disorder must be included in the differential diagnosis of lymphoid interstitial pneumonitis and of bilateral mediastinal lymph node enlargement leading to superior vena caval syndrome.

Anti-Inflammatory Agents↗
PubMed1996

6-methylprednisolone 'mini-pulses': a new modality of glucocorticoid treatment in systemic onset juvenile chronic arthritis.

From 1989 to 1994 we have been following in our Department 22 patients (12 males, 10 females, age range 1-13.5 years) affected by sJCA who underwent glucocorticoid (GC) treatment. These patients were randomised to receive for 6 months two different GC schedules: group A (12) received 6 methylprednisolone (6MP) i.v. for 3 days with 5 mg/kg/d and for an additional 3 days at 2.5 mg/kg/d followed by po prednisone (1 mg/kg/d); group B (10) received po prednisone (1 mg/kg/d). A remarkable decrease of disease activity and fever score and a prompt improvement of joint involvement were observed. A CPR serum concentration decrease associated to a consistent increase of Hb over baseline values were disclosed in group A. GC cumulative daily requirement was significantly lower in group A. Four patients from group B but only one from group A developed a cushingoid appearance: no differences of BMI were found in the two groups. Our study shows that in sJCA patients i.v. GC mini pulses are effective on early clinical and biological parameters of inflammation and requires a lower cumulative daily dosage than conventional oral GC treatment.

Administration, Oral↗
PubMed1996

Outgrowth of interleukin-2-dependent T cell lines with cytotoxic activity against mesothelial cells from cultures of peritoneal effluent cells of children on CPD.

Previous studies on the peritoneal immune system described the presence of activated T lymphocytes in peritoneal effluents (PE) from patients on chronic peritoneal dialysis (CPD), and showed that mesothelial cells (MC) can present antigens to T cells. In order to better define phenotypic and functional characteristics of T cells and their interactions with MC, we isolated PE cells from 15 children. At the immunophenotypic analysis, high percentages of activated T cells were identified (mean value: 15% double staining for CD3/DR; 12% CD25+). T cells with gamma/delta T cell receptor (mean 5%) and natural killer cells (mean 17%) were also present in elevated numbers. MC lines (n = 7) and interleukin-2-dependent T cell lines (9 CD4+; 1 CD8+) were also obtained by incubating PE cells under different conditions. Two cell lines showed a major histocompatibility complex (MHC) restricted cytotoxic activity against autologous MC; two lines killed allogeneic MC; one line killed both autologous and allogeneic MC. Although the hypothesis that activated T cells could kill MC after recognition of surface structures modified by dialysis fluid, or during antigen presentation, needs to be further investigated, our data suggest that the subsets of lymphocytes we identified could play an important role in the mechanisms of peritoneal membrane defense.

Adolescent↗