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Biomedical subjects

V Pistoia

Publications and source records attributed to V Pistoia.

At least 19 recordsLinked to original sources
PubMed2006

Bone marrow mesenchymal stromal cells (BM-MSCs) from healthy donors and auto-immune disease patients reduce the proliferation of autologous- and allogeneic-stimulated lymphocytes in vitro.

OBJECTIVES: To investigate the ability of bone marrow (BM)-derived mesenchymal stromal cells (BM-MSCs) in suppressing the proliferation of stimulated lymphocytes across a range of conditions including autologous BM-MSCs derived from autoimmune disease (AD) patients. METHODS: In vitro cultures of BM-MSCs from healthy donors and AD patients were established and characterized by their differentiation potential into adipocytes and osteoblasts, and their fibroblast-colony-forming unit (CFU-F) ability and phenotype by flow cytometry. BM-MSCs (irradiated and non-irradiated) from healthy and AD patients were tested for their ability to suppress the in vitro proliferation of autologous and allogeneic peripheral blood mononuclear cells (PBMC) (from healthy donors and patients suffering from various ADs) stimulated with anti-CD3epsilon antibody alone or in combination with anti-CD28 antibody. The anti-proliferative effect of the BM-MSCs from healthy donors was tested also on transformed B-cell lines as a model of non-antigen-stimulated lymphocytes. RESULTS: BM-MSCs from healthy donors and AD patients reduced the proliferation of autologous and allogeneic PBMCs by up to 90% in a cell dose-dependent fashion. The immunosuppression was independent of the proliferation of the BM-MSCs and was also effective on already proliferating cells. It was independent also of the clinical activity of AD. An MSC dose-dependent pattern of suppression of proliferation was observed also with transformed B-cell lines, similar to that observed with proliferating PBMC. CONCLUSIONS: The BM-MSCs exhibit extensive anti-proliferative properties against lymphocytes under different conditions. This property might offer a form of immunomodulatory cellular therapy for AD patients if further confirmed in animal models.

Adipocytes↗
PubMed2006

Angiogenesis in a human neuroblastoma xenograft model: mechanisms and inhibition by tumour-derived interferon-gamma.

Tumour progression in neuroblastoma (NB) patients correlates with high vascular index. We have previously shown that the ACN NB cell line is tumorigenic and angiogenic in immunodeficient mice, and that interferon-gamma (IFN-gamma) gene transfer dampens ACN tumorigenicity. As IFN-gamma represses lymphocyte-induced tumour angiogenesis in various murine models and inhibits proliferation and migration of human endothelial cells, we have investigated the antiangiogenic activity of tumour-derived IFN-gamma and the underlying mechanism(s). In addition, we characterised the tumour vasculature of the ACN xenografts, using the chick embryo chorioallantoic membrane assay. We show that the ACN/IFN-gamma xenografts had a lower microvessel density and less in vivo angiogenic potential than the vector-transfected ACN/neo. The vascular channels of both xenografts were formed by a mixed endothelial cell population of murine and human origin, as assessed by the FICTION (fluorescence immunophenotyping and interphase cytogenetics) technique. With respect to ACN/neo, the ACN/IFN-gamma xenografts showed more terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling-positive human and murine endothelial cells, suggesting that inhibition of angiogenesis by IFN-gamma was dependent on the induction of apoptosis, likely mediated by nitric oxide. Once the dual origin of tumour vasculature is confirmed in NB patients, the xenograft model described here will prove useful in testing the efficacy of different antiangiogenic compounds.

Animals↗
PubMed2006

Catastrophic relapse of Evans syndrome five years after allogeneic BMT notwithstanding full donor chimerism. Terminal hemolytic-uremic syndrome.

A patient with severe Evans syndrome received an allo-BMT from his HLA-identical sister on November, 2000. Full marrow and blood donor chimerism were achieved only after 5 donor lymphocyte infusions (DLI), and coincided with complete clinical remission and disappearence of auto-antibodies. Five years later, hemolytic anemia recurred with rapid increase of serum bilirubin to over 50 mg%: he responded to combined therapy, but died on day +17 from admission of an acute hemolytic uremic syndrome (HUS). All circulating blood cells, including erythrocytes, were 100% donor. Ex vivo cultured and expanded T and B cells from the peripheral blood were also 100% donor. The supernatants from B cell cultures, containing either IgM or IgG, did not react with a panel of erythrocytes. Thus in this typical autoimmune disease with a predominant B cell pathogenesis the donor immune system resulted "innocent of autoimmunity". The persistence of long-lived recipient autoreactive plasma-cell lines in survival niches, still producing autoantibodies, may be hypothesized for this and similar cases. The postulated graft-versus-autoimmunity (GVA) effect was apparently not sufficient to eradicate autoimmunity in this patient.

Adolescent↗
PubMed2006

Lymphoproliferative disorders and chemokines.

Chemokines are low molecular weight cytokines specialized in leukocyte recruitment. Recent studies have shown that tumor cells of hematopoietic and non hematopoietic origin express different chemokine receptors that may be involved in neoplastic cell growth, metastasis and angiogenesis. Human lymphoproliferative disorders arise from the malignant transformation of normal lymphoid cells frozen at discrete maturational stages. Studies performed with acute or chronic lymphoproliferative disorders have shown that CXCR4, the unique receptor for CXCL12, is up-regulated in many B and T cells malignancies and may be involved in metastatic localization of the neoplastic elements. Additional chemokine receptors are expressed in the individual lymphoproliferative disorders, but some of these are often non functional. Here we shall review the state of the art on chemokine receptor expression and function in human lymphoproliferative disorders, stressing the potential value of chemokines receptors as novel therapeutic targets. In this respect, small antagonistic peptides are being produced by pharmaceutical companies and hold great promise for clinical application.

Animals↗
PubMed2004

Low-dose interferon-gamma-producing human neuroblastoma cells show reduced proliferation and delayed tumorigenicity.

Interferon-gamma (IFN-gamma) directs T helper-1 cell differentiation and mediates antitumour effects in preclinical models. However, high-dose IFN-gamma is toxic in vivo, and IFN-gamma-transfected neuroblastoma (NB) cells secreting high amounts of the cytokine may be lost due to cell apoptosis or differentiation. Two human NB cell lines (ACN and SK-N-BE2(c)) differing as to genetic and phenotypic features were transfected with the human IFN-gamma gene and selected on the grounds of the low concentrations of IFN-gamma produced. In both IFN-gamma-transfected cell lines, autocrine and paracrine activation of IFN-gamma-mediated pathways occurred, leading to markedly reduced proliferation rate, to increased expression of surface HLA and CD40 molecules and of functional TNF binding sites. ACN/IFN-gamma cells showed a significantly delayed tumorigenicity in nude mice as compared to parental cells. ACN/IFN-gamma tumours were smaller, with extensive necrotic area as a result of a damaged and defective microvascular network. In addition, a significant reduction in the proliferation index was observed. This is the first demonstration that IFN-gamma inhibits in vivo proliferation of NB cell by acting on the tumour cell itself. This effect adds to the immunoregulatory and antiangiogenic activities operated by IFN-gamma in syngeneic tumour-bearing hosts.

Animals↗
PubMed2003

Expression of costimulatory molecules in human neuroblastoma. Evidence that CD40+ neuroblastoma cells undergo apoptosis following interaction with CD40L.

Tumour cells display low to absent expression of costimulatory molecules. Here, we have investigated the expression of costimulatory molecules (CD40, CD80, CD86, PD-1L, B7H2, OX40L and 4-1BBL) in human neuroblastoma (NB) cells, since virtually no information is available on this issue. Both established NB cell lines and primary tumours were tested by RT-PCR and flow cytometry. Neuroblastoma cell lines expressed the transcripts of all costimulatory molecule genes, but not the corresponding proteins. Culture of NB cell lines with human recombinant (r)IFN-gamma induced surface expression of CD40 in half of them. Primary NB cells showed CD40, CD80, CD86, OX40L, 4-1BBL, but not PD-1L and B7H2, mRNA expression. Surface CD40 was consistently detected on primary NB cells by flow cytometry. Interferon-gamma gene-transfected NB cells expressed constitutively surface CD40 and were induced into apoptosis by incubation with rCD40L through a caspase-8-dependent mechanism. CD40 may represent a novel therapeutic target in NB.

Antigens, Differentiation↗
PubMed2002

CD10 is a marker for cycling cells with propensity to apoptosis in childhood ALL.

CD10 constitutes a favourable prognostic marker for childhood acute lymphoblastic leukaemia. Since correlations between CD10, cell cycle and apoptotic abilities were demonstrated in various cell types, we investigated whether differences existed in the cycling/apoptotic abilities of CD10-positive and CD10-negative B acute lymphoblastic leukaemia cells. Twenty-eight cases of childhood acute lymphoblastic leukaemia (mean age of 6.8 years) were subdivided into two groups according to high (17 cases, 93.2+/-4.5%, MRFI 211+/-82 CD10-positive cells) or low (11 cases, 11.5+/-6.2%, MRFI 10+/-7 CD10-negative cells) expression of CD10. CD10-positive acute lymphoblastic leukaemia cells were cycling cells with elevated c-myc levels and propensity to apoptosis, whereas CD10-negative acute lymphoblastic leukaemia cells had lower cycling capacities and c-myc levels, and were resistant to apoptosis in vitro. A close correlation between all these properties was demonstrated by the observations that the few CD10-positive cells found in the CD10-negative acute lymphoblastic leukaemia group displayed elevated c-myc and cycling capacities and were apoptosis prone. Moreover, exposure of CD10-positive acute lymphoblastic leukaemia B cells to a peptide nucleic acid anti-gene specific for the second exon of c-myc caused inhibition of c-myc expression and reduced cell cycling and apoptotic abilities as well as decreased CD10 expression.

Antigens, CD↗
PubMed2002

Involvement of the hypothalamic-pituitary-adrenal axis in children with oligoarticular-onset idiopathic arthritis.

Adult patients with rheumatic arthritis and other rheumatic disorders show inappropriate cortisol secretion and peculiar CRH promoter gene polymorphisms. So far, no data are available about this topic in children with juvenile idiopathic arthritis (JIA). We have studied a series of 13 prepubertal patients (10 female, 3 male) affected with oligoarticular JIA (o-JIA) without clinical and biological signs of disease activity (ESR and IL-6). ACTH plasma concentrations were significantly increased at 8 a.m. in o-JIA patients, whereas no differences were found in cortisol plasma concentrations. The ACTH/cortisol ratio was significantly increased in o-JIA patients with respect to the normal population both at 8 a.m. and at noon. DHEAS and testosterone plasma concentration did not statistically differ in the two populations. The genetic study was aimed at defining the prevalence of polymorphisms A1 and A2 in o-JIA patients, but we failed to find allelic or genotypic differences. Our study suggests the presence of a partial resistance to ACTH with a dysregulated pattern of secretion also in inactive o-JIA patients. These preliminary data need further confirmation in larger pediatric studies.

Adrenocorticotropic Hormone↗
PubMed2002

MICA gene polymorphisms in an Italian paediatric series of juvenile Behçet disease.

The objective of this study was to investigate MICA (major histocompatibility complex MHC class I chain-related genes) polymorphisms in an Italian series of patients with juvenile Behcet disease (jBD) and to compare these genetic findings with the high prevalence of inflammatory mucosal disease, which occurs in Western populations. Ten families which included at least 1 affected patient were studied. We genotyped 18 patients (13 children and 5 adults) affected with the complete or incomplete form of jBD comparing the results to those found in a population of 20 apparently healthy individuals. The MICA transmembrane polymorphism was analysed by PCR and polyacrylamide gel electrophoresis. HLA typing was assessed by SSP-PCR technique. Statistical analysis was performed using chi2 based methods. In our series the prevalence of gastrointestinal disease was high (41%). Seven of 10 patients were HLA-B51 positive. MICA A6 allele was present in 70% of probands as compared to 25% of an ethnically matched control population. On the other hand, MICA A5.1 was present in 20% of probands as compared to 60% in controls. Out of 5 A6 homozygotes, 2 probands and 2 affected relatives developed a severe gut inflammatory disease. The study of MICA gene polymorphisms disclosed an independent association with genetic risk for jBD. The combination of MICA A6 and HLA-B51 is the strongest genetic marker for this disease. Homozygous A6 patients seem to develop more severe mucosal gut involvement. This finding sheds light on the role of a receptor for MICA, named NKG2D, presented by natural killer cells, and CD8+, alphabetaT cells and gammadeltaT cells, usually localised in gut mucosa.

Adult↗
PubMed2001

Cytokine gene expression in neoplastic B cells from human mantle cell, follicular, and marginal zone lymphomas and in their postulated normal counterparts.

Cytokines may promote tumor growth by paracrine and/or autocrine pathways. Little information is available because malignant cells differ from their normal counterparts for the cytokine repertoire they express. Here we have investigated by reverse transcription-PCR the expression of 22 cytokine genes in neoplastic B lymphocytes from six patients with mantle cell lymphoma, 10 with follicular lymphoma, and 5 with marginal zone lymphoma and in their normal counterparts, i.e., naive, germinal center, and memory B cells, purified from tonsils. The overall profiles of cytokine gene expression in neoplastic B cells and in the corresponding normal B-cell subsets were similar, but some "holes" in the repertoire of malignant versus normal B lymphocytes were detected. Different "hole" combinations were identified consistently in mantle cell lymphoma, follicular lymphoma, and marginal zone lymphoma, thus representing molecular fingerprints of each individual lymphoma entity.

B-Lymphocytes↗
PubMed2001

Lack of HLA-class I antigens in human neuroblastoma cells: analysis of its relationship to TAP and tapasin expression.

We studied the constitutive and the interferon (IFN)-gamma-induced expression of HLA class I antigen heavy chain, beta2-microglobulin (beta2m), TAP-1, TAP-2 and tapasin in a panel of eleven neuroblastoma cell lines. Surface expression of HLA class I antigens was low in eight out of eight neuroblastoma cell lines bearing MYC-N amplification and/or 1p deletion, while two out of three neuroblastoma cell lines lacking these genetic alterations showed normal expression. IFN-gamma treatment restored HLA class I antigen surface expression in all neuroblastoma cell lines. Eight out of 11 neuroblastoma cell lines did not express TAP-1 mRNA and three of them also lacked TAP-2 mRNA. beta2 m mRNA was barely detectable or absent in five neuroblastoma cell lines, while tapasin mRNA was always expressed. IFN-gamma upregulated the expression of HLA class I heavy chain, beta2 m, TAP-1, TAP-2 and tapasin, as detected at mRNA or protein level. Post-transcriptional events were involved in altered TAP-1 and beta2 m expression in one peculiar neuroblastoma cell line. These data indicate that multiple mechanisms play a role in the HLA class I antigen-deficient phenotype of human neuroblastoma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Interferon gamma and tumour necrosis factor alpha are overexpressed in bone marrow T lymphocytes from paediatric patients with aplastic anaemia.

Twelve paediatric patients with aplastic anaemia and two groups of normal control subjects underwent flow cytometric analysis for intracytoplasmic expression of gamma interferon (gamma-IFN) and tumour necrosis factor alpha (TNF-alpha) in bone marrow and peripheral blood CD4+ and CD8+ cells. The same cytokines were tested, by immunoassay, in culture supernatants from unstimulated bone marrow mononuclear cells (MNCs). Marrow CD4+ and CD8+ cells expressing gamma-IFN and TNF-alpha were significantly increased in the patients in comparison with normal control subjects (P from < 0.05 to < 0.0001 in the different cellular subsets). Patients' marrow CD4+ and CD8+ cells containing gamma-IFN and TNF-alpha were significantly increased when compared with the same cell fractions from paired peripheral blood samples (P from < 0.05 to < 0.0001 in the various cellular subsets). In the supernatant of marrow MNCs, gamma-IFN and TNF-alpha were detected in four out of eight and five out of eight cases, respectively, whereas neither cytokine was traceable in the control subjects. Patients' peripheral blood CD4+ and CD8+ cells containing gamma-IFN and TNF-alpha were not significantly increased in comparison with those from normal control subjects. Whereas patients with favourable and unfavourable outcomes had no significantly different proportions of marrow gamma-IFN+/CD4+ and gamma-IFN+/CD8+ cells, the percentages of marrow CD4+ and CD8+ cells containing TNF-alpha were significantly lower in subjects with favourable than in those with unfavourable outcome. Overall, these findings show that, in aplastic patients, T cells overexpressing gamma-IFN and TNF-alpha concentrate in the bone marrow and that intracytoplasmic expression of TNF-alpha in marrow CD4+ and CD8+ cells is associated with an unfavourable clinical course.

Adolescent↗
PubMed2001

Plasma levels of soluble CD30 are increased in children with chronic renal failure and with primary growth deficiency and decrease during treatment with recombination human growth hormone.

BACKGROUND: Previous studies have suggested that in vivo Th2 lymphocyte activation is related to increased soluble CD30 (sCD30) plasma levels. As various hormones (dehydroepiandrosterone, glucocorticoids, progesterone) can regulate the Th1/Th2 balance, and because growth hormone (GH) enhances lymphocyte function, we measured sCD30 plasma levels, before and after treatment with recombinant human GH (rhGH), in children with growth failure due to chronic renal failure (CRF) or to isolated GH deficiency in order to evaluate the potential effects of rhGH treatment on Th1/Th2 balance. METHODS: sCD30 plasma levels were determined by ELISA assay in 30 children with CRF (mean age 10.7+/-3.7 years), in five children with isolated GH deficiency (mean age 11.4+/-2.6 years), and in 10 normal controls (mean age 10.1+/-3.5 years). RESULTS: sCD30 levels were higher in the 30 children with CRF than in the 10 controls (179.8+/-79.4 vs 11.3+/-10.9 U/ml, P<0.001) exhibiting an inverse correlation with glomerular filtration rate (GFR) (r=-0.7860, P<0.001). In 11 children with CRF, after 19.9+/-16.7 months of rhGH treatment, a decrease of sCD30 plasma level (170+/-50 vs 134+/-49 U/ml, P<0.01) was observed. The five children with primary GH deficiency had higher sCD30 plasma level than controls (mean 147+/-105 vs 11+/-10 U/ml, P<0.004) and sCD30 plasma levels decreased to 95.2+/-109.6 U/ml after rhGH treatment. CONCLUSIONS: The finding that rhGH treatment decreased sCD30 plasma levels in children with CRF, and that children with primary GH deficiency had higher sCD30 plasma levels than controls, suggest that GH may regulate CD30 expression and possibly the balance of Th1/Th2. Whether the uraemia-induced increase in sCD30 is due to decreased renal excretion, to overproduction or both, remains to be determined.

Adolescent↗
PubMed2000

Expression and function of IL-12 and IL-18 receptors on human tonsillar B cells.

IL-12 activates murine and human B cells, but little information is available as to the expression and function of IL-12R on human B lymphocytes. Here we show that the latter cells, freshly isolated from human tonsils, expressed the transcripts of both beta1 and beta2 chains of IL-12R and that beta2 chain mRNA was selectively increased (4- to 5-fold) by incubation with Staphylococcus aureus Cowan I bacteria or IL-12. B cell stimulation with IL-12 induced de novo expression of the transcripts of the two chains of IL-18R, i.e., IL-1 receptor-related protein and accessory protein-like. Functional studies showed that both IL-12 and IL-18 signaled to B cells through the NF-kappaB pathway. In the case of IL-12, no involvement of STAT transcription factors, and in particular of STAT-4, was detected. c-rel and p50 were identified as the members of NF-kappaB family involved in IL-12-mediated signal transduction to B cells. IL-12 and IL-18 synergized in the induction of IFN-gamma production by tonsillar B cells, but not in the stimulation of B cell differentiation, although either cytokine promoted IgM secretion in culture supernatants. Finally, naive but not germinal center or memory, tonsillar B cells were identified as the exclusive IL-12 targets in terms of induction of NF-kappaB activation and of IFN-gamma production.

B-Lymphocyte Subsets↗
PubMed2000

Analysis of stepwise genetic changes in an AIDS-related Burkitt's lymphoma.

In this study, immunoglobulin variable (Ig V) region genes, c-myc re-arrangement and sequence and p53 status were analyzed in clones derived from a Burkitt's lymphoma cell line (LAM) in which it was previously demonstrated that Epstein-Barr virus (EBV) infection occurred late during lymphomagenesis. Such evidence was based on the finding that 2 groups of cellular clones, characterized by the same c-myc re-arrangement but different EBV-fused termini, were obtained from the LAM cell line. The Ig V gene sequences were identical for the 2 groups of clones with different EBV-fused termini. The Ig variable heavy (V(H)) gene sequence displayed a substantial accumulation of point mutations (but no intra-clonal diversification), whereas the productive Ig V lambda (V(lambda)) gene sequence was virtually unmutated. Studies on the Ig V kappa (V(kappa)) locus suggested a receptor revision event (with a switch from kappa to lambda chain production) prior to EBV infection. Likewise, it was determined that the mutations observed in both p53 alleles and in the re-arranged c-myc gene occurred before EBV infection. Based on these findings, we present a model for the various steps of lymphomagenesis. It is proposed that stimulation by an antigen or a superantigen initially favored the clonal expansion and accumulation of other cytogenetic changes, including those involved in receptor editing. These events occurred prior to or during the germinal center (GC) phase of B-cell maturation. Thereafter, possibly upon exit of the cells from the GC, EBV infection occurred, further promoting lymphomagenesis.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Stromal cell-derived factor-1 as a chemoattractant for follicular center lymphoma B cells.

BACKGROUND: Follicular center lymphoma displays widespread lymph node involvement at diagnosis. The chemoattractants that control the locomotion of follicular center lymphoma B cells have not been established. Stromal cell-derived factor-1 (SDF-1) is a CXC-class chemokine that enhances the migration of normal human B cells and is expressed in peripheral lymphoid tissues. Here we have investigated 1) whether SDF-1 stimulates the in vitro locomotion of follicular center lymphoma B cells and of their presumed normal counterparts (i. e., germinal center B cells) and 2) whether the same cells express SDF-1 transcripts. METHODS: B cells were purified by immunomagnetic bead manipulation. Messenger RNA was detected by reverse transcription-polymerase chain reaction. Migration was assessed by the filter and collagen invasion assays. All P values were two sided. RESULTS: Follicular center lymphoma B lymphocytes showed a statistically significant migratory response to 300 ng/mL SDF-1, both in the filter and in the collagen assays (P =.002 for each). Such response was mediated by the SDF-1 receptor, CXCR4. CD40 monoclonal antibody (MAb) and tonsillar germinal center B cells treated with CD40 MAb and recombinant interleukin 4, but not freshly isolated, migrated statistically significantly faster in the presence than in the absence of SDF-1 (P =.002 in both filter and collagen assays). Freshly isolated follicular center lymphoma and germinal center B cells expressed SDF-1 transcripts. CONCLUSIONS: This study shows that SDF-1 substantially enhances the migration of follicular center lymphoma B cells but not the migration of freshly purified germinal center B cells. This difference may be related to the extended survival of follicular center lymphoma versus germinal center B cells. SDF-1 produced in follicular center lymphoma lymph nodes may play a role in the local dissemination of tumor cells.

Antibodies, Monoclonal↗