Publications by authors named "Sabrina Chiesa"

21 Publications

  • Page 1 of 1

A novel knock-in mouse model of cryopyrin-associated periodic syndromes with development of amyloidosis: Therapeutic efficacy of proton pump inhibitors.

J Allergy Clin Immunol 2020 01 10;145(1):368-378.e13. Epub 2019 Jun 10.

UOSD Centro Malattie Autoinfiammatorie ed Immunodeficienze, IRCCS Istituto G. Gaslini, Genova, Italy. Electronic address:

Background: Cryopyrin-associated periodic syndromes (CAPS) are a group of autoinflammatory diseases linked to gain-of-function mutations in the NOD-like receptor family, pyrin domain containing 3 (NLRP3) gene, which cause uncontrolled IL-1β secretion. Proton pump inhibitors (PPIs), which are commonly used as inhibitors of gastric acid production, also have anti-inflammatory properties, protect mice from sepsis, and prevent IL-1β secretion by monocytes from patients with CAPS.

Objective: We sought to develop a novel Nlrp3 knock-in (KI) mouse model of CAPS to study amyloidosis, a severe CAPS complication, and test novel therapeutic approaches.

Methods: We generated KI mice by engineering the N475K mutation, which is associated with the CAPS phenotype, into the mouse Nlrp3 gene. KI and wild-type mice received PPIs or PBS intraperitoneally and were analyzed for survival, inflammation, cytokine secretion, and amyloidosis development.

Results: Mutant Nlrp3 KI mice displayed features that recapitulate the immunologic and clinical phenotype of CAPS. They showed systemic inflammation with high levels of serum proinflammatory cytokines, inflammatory infiltrates in various organs, and amyloid deposits in the spleen, liver, and kidneys. Toll-like receptor stimulated macrophages from KI mice secreted high levels of IL-1β, IL-18, and IL-1α but low amounts of IL-1 receptor antagonist. Treatment of KI mice with PPIs had a clear clinical effect, showing a reduction in inflammatory manifestations, regression of amyloid deposits, and normalization of proinflammatory and anti-inflammatory cytokine production by macrophages.

Conclusion: Nlrp3 KI mice displayed a CAPS phenotype with many characteristics of autoinflammation, including amyloidosis. The therapeutic effectiveness of PPIs associated with a lack of toxicity indicates that these drugs could represent relevant adjuvants to the anti-IL-1 drugs in patients with CAPS and other IL-1-driven diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2019.05.034DOI Listing
January 2020

CD70 Deficiency due to a Novel Mutation in a Patient with Severe Chronic EBV Infection Presenting As a Periodic Fever.

Front Immunol 2017 29;8:2015. Epub 2018 Jan 29.

Clinica Pediatria e Reumatologia, Istituto Giannina Gaslini, Genova, Italy.

Primary immunodeficiencies with selective susceptibility to EBV infection are rare conditions associated with severe lymphoproliferation. We followed a patient, son of consanguineous parents, referred to our center for recurrent periodic episodes of fever associated with tonsillitis and adenitis started after an infectious mononucleosis and responsive to oral steroid. An initial diagnosis of periodic fever, aphthous stomatitis, pharyngitis, cervical adenitis syndrome was done. In the following months, recurrent respiratory infections and episodes of keratitis were also observed, together with a progressive reduction of immunoglobulin levels and an increase of CD20 cells. Cell sorting and EBV PCR showed 25,000 copies for 100,000 leukocytes with predominant infection of B lymphocytes. Lymph node's biopsy revealed reactive lymphadenopathy with paracortical involvement consistent with a chronic EBV infection. Molecular analysis of , and genes did not detect any pathogenic mutation. The patients underwent repeated courses of anti-CD20 therapy with only a partial control of the disease, followed by stem cell transplantation with a complete normalization of clinical and immunological features. Whole exome sequencing of the trio was performed. Among the variants identified, a novel loss of function homozygous c.163-2A>G mutation of the gene, affecting the exon 2 AG-acceptor splice site, fit the expected recessive model of inheritance. Indeed, deficiency of both CD27, and, more recently, of its ligand CD70, has been reported as a cause of EBV-driven lymphoproliferation and hypogammaglobulinemia. Cell surface analysis of patient-derived PHA-T cell blasts and EBV-transformed lymphoblastoid cell lines confirmed absence of CD70 expression. In conclusion, we describe a case of severe chronic EBV infection caused by a novel mutation of CD70 presenting with recurrent periodic fever.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2017.02015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5796890PMC
January 2018

CD56brightCD16- NK Cells Produce Adenosine through a CD38-Mediated Pathway and Act as Regulatory Cells Inhibiting Autologous CD4+ T Cell Proliferation.

J Immunol 2015 Aug 19;195(3):965-72. Epub 2015 Jun 19.

Laboratory of Immunogenetics and CeRMS, Department of Medical Sciences, University of Turin, Turin 10126, Italy; Immunologia dei Trapianti, Città della Salute e della Scienza, Turin 10126, Italy;

Recent studies suggested that human CD56(bright)CD16(-) NK cells may play a role in the regulation of the immune response. Since the mechanism(s) involved have not yet been elucidated, in the present study we have investigated the role of nucleotide-metabolizing enzymes that regulate the extracellular balance of nucleotides/nucleosides and produce the immunosuppressive molecule adenosine (ADO). Peripheral blood CD56(dim)CD16(+) and CD56(bright)CD16(-) NK cells expressed similar levels of CD38. CD39, CD73, and CD157 expression was higher in CD56(bright)CD16(-) than in CD56(dim)CD16(+) NK cells. CD57 was mostly expressed by CD56(dim)CD16(+) NK cells. CD203a/PC-1 expression was restricted to CD56(bright)CD16(-) NK cells. CD56(bright)CD16(-) NK cells produce ADO and inhibit autologous CD4(+) T cell proliferation. Such inhibition was 1) reverted pretreating CD56(bright)CD16(-) NK cells with a CD38 inhibitor and 2) increased pretreating CD56(bright)CD16(-) NK cells with a nucleoside transporter inhibitor, which increase extracellular ADO concentration. CD56(bright)CD16(-) NK cells isolated from the synovial fluid of juvenile idiopathic arthritis patients failed to inhibit autologous CD4(+) T cell proliferation. Such functional impairment could be related to 1) the observed reduced CD38/CD73 expression, 2) a peculiar ADO production kinetics, and 3) a different expression of ADO receptors. In contrast, CD56(bright)CD16(-) NK cells isolated from inflammatory pleural effusions display a potent regulatory activity. In conclusion, CD56(bright)CD16(-) NK cells act as "regulatory cells" through ADO produced by an ectoenzymes network, with a pivotal role of CD38. This function may be relevant for the modulation of the immune response in physiological and pathological conditions, and it could be impaired during autoimmune/inflammatory diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4049/jimmunol.1500591DOI Listing
August 2015

Single amino acid charge switch defines clinically distinct proline-serine-threonine phosphatase-interacting protein 1 (PSTPIP1)-associated inflammatory diseases.

J Allergy Clin Immunol 2015 Nov 27;136(5):1337-45. Epub 2015 May 27.

Children's Hospital and Clinics of Minnesota, Saint Paul, Minn.

Background: Hyperzincemia and hypercalprotectinemia (Hz/Hc) is a distinct autoinflammatory entity involving extremely high serum concentrations of the proinflammatory alarmin myeloid-related protein (MRP) 8/14 (S100A8/S100A9 and calprotectin).

Objective: We sought to characterize the genetic cause and clinical spectrum of Hz/Hc.

Methods: Proline-serine-threonine phosphatase-interacting protein 1 (PSTPIP1) gene sequencing was performed in 14 patients with Hz/Hc, and their clinical phenotype was compared with that of 11 patients with pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome. PSTPIP1-pyrin interactions were analyzed by means of immunoprecipitation and Western blotting. A structural model of the PSTPIP1 dimer was generated. Cytokine profiles were analyzed by using the multiplex immunoassay, and MRP8/14 serum concentrations were analyzed by using an ELISA.

Results: Thirteen patients were heterozygous for a missense mutation in the PSTPIP1 gene, resulting in a p.E250K mutation, and 1 carried a mutation resulting in p.E257K. Both mutations substantially alter the electrostatic potential of the PSTPIP1 dimer model in a region critical for protein-protein interaction. Patients with Hz/Hc have extremely high MRP8/14 concentrations (2045 ± 1300 μg/mL) compared with those with PAPA syndrome (116 ± 74 μg/mL) and have a distinct clinical phenotype. A specific cytokine profile is associated with Hz/Hc. Hz/Hc mutations altered protein binding of PSTPIP1, increasing interaction with pyrin through phosphorylation of PSTPIP1.

Conclusion: Mutations resulting in charge reversal in the y-domain of PSTPIP1 (E→K) and increased interaction with pyrin cause a distinct autoinflammatory disorder defined by clinical and biochemical features not found in patients with PAPA syndrome, indicating a unique genotype-phenotype correlation for mutations in the PSTPIP1 gene. This is the first inborn autoinflammatory syndrome in which inflammation is driven by uncontrolled release of members of the alarmin family.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2015.04.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6591125PMC
November 2015

Autophagy contributes to inflammation in patients with TNFR-associated periodic syndrome (TRAPS).

Ann Rheum Dis 2013 Jun 31;72(6):1044-52. Epub 2012 Oct 31.

Laboratory of Molecular Genetics, Giannina Gaslini Institute, Genoa, Italy.

Objectives: Tumour necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) is caused by TNFRSF1A mutations, known to induce intracellular retention of the TNFα receptor 1 (TNFR1) protein, defective TNFα-induced apoptosis, and production of reactive oxygen species. As downregulation of autophagy, the main cellular pathway involved in insoluble aggregate elimination, has been observed to increase the inflammatory response, we investigated whether it plays a role in TRAPS pathogenesis.

Methods: The possible link between TNFRSF1A mutations and inflammation in TRAPS was studied in HEK-293T cells, transfected with expression constructs for wild-type and mutant TNFR1 proteins, and in monocytes derived from patients with TRAPS, by investigating autophagy function, NF-κB activation and interleukin (IL)-1β secretion.

Results: We found that autophagy is responsible for clearance of wild-type TNFR1, but when TNFR1 is mutated, the autophagy process is defective, probably accounting for mutant TNFR1 accumulation as well as TRAPS-associated induction of NF-κB activity and excessive IL-1β secretion, leading to chronic inflammation. Autophagy inhibition due to TNFR1 mutant proteins can be reversed, as demonstrated by the effects of the antibiotic geldanamycin, which was found to rescue the membrane localisation of mutant TNFR1 proteins, reduce their accumulation and counteract the increased inflammation by decreasing IL-1β secretion.

Conclusions: Autophagy appears to be an important mechanism in the pathogenesis of TRAPS, an observation that provides a rationale for the most effective therapy in this autoinflammatory disorder. Our findings also suggest that autophagy could be proposed as a novel therapeutic target for TRAPS and possibly other similar diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/annrheumdis-2012-201952DOI Listing
June 2013

Principles of inflammation for the pediatrician.

Pediatr Clin North Am 2012 Apr;59(2):225-43

UO Pediatria II, G. Gaslini Institute, Largo G. Gaslini 5, 16147 Genova, Italy.

The immune system consists of 2 branches: innate and adaptive. The former represents the first line of host defense during infection and plays a key role in the early recognition and protection against invading pathogens. The latter orchestrates elimination of pathogens in the late phase of infection and leads to the generation of immunologic memory. Innate and adaptive immunity should not be considered separate compartments. Innate and adaptive immune responses represent an integrated system of host defense. The authors review the mechanisms driving the induction and perpetuation of the inflammatory responses observed during pathogen-associated, autoimmune, and autoinflammatory diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.pcl.2012.03.004DOI Listing
April 2012

Mesenchymal stem cells impair in vivo T-cell priming by dendritic cells.

Proc Natl Acad Sci U S A 2011 Oct 29;108(42):17384-9. Epub 2011 Sep 29.

Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, 16132 Genoa, Italy.

Dendritic cells (DC) are highly specialized antigen-presenting cells characterized by the ability to prime T-cell responses. Mesenchymal stem cells (MSC) are adult stromal progenitor cells displaying immunomodulatory activities including inhibition of DC maturation in vitro. However, the specific impact of MSC on DC functions, upon in vivo administration, has never been elucidated. Here we show that murine MSC impair Toll-like receptor-4 induced activation of DC resulting in the inhibition of cytokines secretion, down-regulation of molecules involved in the migration to the lymph nodes, antigen presentation to CD4(+) T cells, and cross-presentation to CD8(+) T cells. These effects are associated with the inhibition of phosphorylation of intracellular mitogen-activated protein kinases. Intravenous administration of MSC decreased the number of CCR7 and CD49dβ1 expressing CFSE-labeled DC in the draining lymph nodes and hindered local antigen priming of DO11.10 ovalbumin-specific CD4(+) T cells. Upon labeling of DC with technetium-99m hexamethylpropylene amine oxime to follow their in vivo biodistribution, we demonstrated that intravenous injection of MSC blocks, almost instantaneously, the migration of subcutaneously administered ovalbumin-pulsed DC to the draining lymph nodes. These findings indicate that MSC significantly affect DC ability to prime T cells in vivo because of their inability to home to the draining lymph nodes and further confirm MSC potentiality as therapy for immune-mediated diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1103650108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3198360PMC
October 2011

Role of IL-1 beta in the development of human T(H)17 cells: lesson from NLPR3 mutated patients.

PLoS One 2011 26;6(5):e20014. Epub 2011 May 26.

Rheumatology Unit, Second Division of Pediatrics G. Gaslini Institute, Genoa, Italy.

Background: T helper 17 cells (T(H)-17) represent a lineage of effector T cells critical in host defence and autoimmunity. In both mouse and human IL-1β has been indicated as a key cytokine for the commitment to T(H)-17 cells. Cryopyrin-associated periodic syndromes (CAPS) are a group of inflammatory diseases associated with mutations of the NLRP3 gene encoding the inflammasome component cryopyrin. In this work we asked whether the deregulated secretion of IL-1β secondary to mutations characterizing these patients could affect the IL-23/IL-17 axis.

Methodology/principal Findings: A total of 11 CAPS, 26 systemic onset juvenile idiopathic arthritis (SoJIA) patients and 20 healthy controls were analyzed. Serum levels of IL-17 and IL-6 serum were assessed by ELISA assay. Frequency of T(H)17 cells was quantified upon staphylococcus enterotoxin B (SEB) stimulation. Secretion of IL-1β, IL-23 and IL-6 by monocyte derived dendritic cells (MoDCs), were quantified by ELISA assay. A total of 8 CAPS and 11 SoJIA patients were also analysed before and after treatment with IL-1β blockade. Untreated CAPS patients showed significantly increased IL-17 serum levels as well as a higher frequency of T(H)17 compared to control subjects. On the contrary, SoJIA patients displayed a frequency of T(H)17 similar to normal donors, but were found to have significantly increased serum level of IL-6 when compared to CAPS patients or healthy donors. Remarkably, decreased IL-17 serum levels and T(H)17 frequency were observed in CAPS patients following in vivo IL-1β blockade. On the same line, MoDCs from CAPS patients exhibited enhanced secretion of IL-1β and IL-23 upon TLRs stimulation, with a reduction after anti-IL-1 treatment.

Conclusion/significance: These findings further support the central role of IL-1β in the differentiation of T(H)17 in human inflammatory conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0020014PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3102666PMC
September 2011

Is there a role for mesenchymal stem cells in autoimmune diseases?

Autoimmunity 2008 Dec;41(8):592-5

Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, Genoa, Italy.

Recent reports have highlighted that adult stem cells are granted with yet poorly understood properties other than multipotentiality. In particular, mesenchymal stem cells (MSCs) represent a subset of adult stromal cells that can down-regulate several functions of the immune cells. In addition, MSCs may promote survival of damaged cells and tissues through paracrine mechanisms, possibly under the guidance of environmental cues. Thus, MSCs clinical application in autoimmune diseases seems an appealing opportunity and preclinical results in different experimental models of autoimmunity further support this strategy. Despite the absolute need for caution related to several clinical and technical issues, MSCs are now on the edge of a new era of clinical applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/08916930802200166DOI Listing
December 2008

Tumor mRNA-transfected dendritic cells stimulate the generation of CTL that recognize neuroblastoma-associated antigens and kill tumor cells: immunotherapeutic implications.

Neoplasia 2006 Oct;8(10):833-42

Laboratory of Oncology, G. Gaslini Children's Hospital, Genoa, Italy.

Several observations suggest a potential role of T-cell-mediated immunity in the control of neuroblastoma (NB). However, the generation of NB-specific cytotoxic T lymphocytes (CTL) on T-cell priming with tumor mRNA-transfected dendritic cells (DC) has never been investigated before. In the present study, the feasibility of this strategy has been analyzed, both in healthy donors and in NB patients. Monocyte-derived DC were raised from three human leukocyte antigen (HLA) A2+ NB patients and seven HLA-A1+ or HLA-A2+ healthy donors transfected with mRNA from four NB cell lines and cocultured with autologous CD8+ lymphocytes. Expanded CTL expressed an effector/memory phenotype and a T cytotoxic 1-like profile of cytokine secretion. CTL specificity was demonstrated by interferon-gamma release on incubation with HLA-matched NB cell lines. The latter cell lines, but not autologous T-cell blasts, were lysed by CTL in an HLA-restricted manner. Cytotoxicity was found to involve the release of granzyme B. When tested for reactivity against NB-associated antigens, CTL from normal individuals recognized anaplastic lymphoma-associated kinase (ALK) and preferentially expressed antigen of melanoma (PRAME) peptides only, whereas patients' CTL reacted also to survivin, telomerase, and tyrosine hydroxylase peptides. This study demonstrates that DC transfected with NB mRNA induce the generation of patients' CTL specific for different NB-associated antigens, supporting the feasibility of NB T-cell immunotherapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1593/neo.06415DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1715922PMC
October 2006

T cell mediated immune responses to Toxoplasma gondii in pregnant women with primary toxoplasmosis.

Microbes Infect 2006 Feb 21;8(2):552-60. Epub 2005 Oct 21.

Laboratory of Oncology, Department of Experimental and Laboratory Medicine, G. Gaslini Scientific Institute, Largo G. Gaslini 5, 16148 Genoa, Italy.

The aim of this study was to investigate T cell immunity to Toxoplasma gondii (Tg) in pregnant women with primary toxoplasmosis. This issue has never been addressed before in humans and available information derives from murine models. Peripheral blood mononuclear cells (PBMC) from pregnant women with primary Tg infection were stimulated with Tg tachyzoites, excretory-secretory antigens (ESA) or recombinant surface antigen-1 (rSAG-1), and tested for proliferation, immunophenotype, cytokine production and antigen specific cytotoxic activity. Pregnant women with primary toxoplasmosis displayed a significant decrease of the CD4/CD8 T cell ratio and a significant increase of circulating T cell receptor (TCR) gammadelta+ cells as compared to their uninfected counterparts. T cells from Tg infected pregnant women proliferated to Tg tachyzoites, ESA or rSAG-1. Most tachyzoite and ESA specific T cell blasts were CD4+, whereas SAG-1 specific blasts were CD4+ and CD8+. ESA and tachyzoite specific T cell blasts displayed a Th1 or Th0 cytokine profile with overexpression of IFN-gamma. This pattern was unchanged upon in vitro exposure of T cells to progesterone, tested at a concentration close to that reached in vivo at the maternal-fetal interface. Finally, tachyzoite or ESA specific T cell blasts lysed, through a granule exocytosis dependent mechanism, autologous lymphoblastoid cell lines presenting Tg antigens. In conclusion, pregnant women with primary toxoplasmosis mounted in vitro Tg-specific Th1/Th0 responses whose impact on neonatal infection warrants further investigation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.micinf.2005.08.008DOI Listing
February 2006

Multiplicity and plasticity of natural killer cell signaling pathways.

Blood 2006 Mar 15;107(6):2364-72. Epub 2005 Nov 15.

Centre d'Immunologie de Marseille-Luminy, INSERM/CNRS, Université de la Méditerranée, Marseille Cedex 09, France.

Natural killer (NK) cells express an array of activating receptors that associate with DAP12 (KARAP), CD3zeta, and/or FcRgamma ITAM (immunoreceptor tyrosine-based activation motif)-bearing signaling subunits. In T and mast cells, ITAM-dependent signals are integrated by critical scaffolding elements such as LAT (linker for activation of T cells) and NTAL (non-T-cell activation linker). Using mice that are deficient for ITAM-bearing molecules, LAT or NTAL, we show that NK cell cytotoxicity and interferon-gamma secretion are initiated by ITAM-dependent and -independent as well as LAT/NTAL-dependent and -independent pathways. The role of these various signaling circuits depends on the target cell as well as on the activation status of the NK cell. The multiplicity and the plasticity of the pathways that initiate NK cell effector functions contrast with the situation in T cells and B cells and provide an explanation for the resiliency of NK cell effector functions to various pharmacologic inhibitors and genetic mutations in signaling molecules.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/blood-2005-08-3504DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1895728PMC
March 2006

Phenotypic and functional characterisation of CCR7+ and CCR7- CD4+ memory T cells homing to the joints in juvenile idiopathic arthritis.

Arthritis Res Ther 2005 12;7(2):R256-67. Epub 2005 Jan 12.

II Division of Pediatrics, University of Genoa, Genoa, Italy.

The aim of the study was to characterise CCR7+ and CCR7- memory T cells infiltrating the inflamed joints of patients with juvenile idiopathic arthritis (JIA) and to investigate the functional and anatomical heterogeneity of these cell subsets in relation to the expression of the inflammatory chemokine receptors CXCR3 and CCR5. Memory T cells freshly isolated from the peripheral blood and synovial fluid (SF) of 25 patients with JIA were tested for the expression of CCR7, CCR5, CXCR3 and interferon-gamma by flow cytometry. The chemotactic activity of CD4 SF memory T cells from eight patients with JIA to inflammatory (CXCL11 and CCL3) and homeostatic (CCL19, CCL21) chemokines was also evaluated. Paired serum and SF samples from 28 patients with JIA were tested for CCL21 concentrations. CCR7, CXCR3, CCR5 and CCL21 expression in synovial tissue from six patients with JIA was investigated by immunohistochemistry. Enrichment of CD4+, CCR7- memory T cells was demonstrated in SF in comparison with paired blood from patients with JIA. SF CD4+CCR7- memory T cells were enriched for CCR5+ and interferon-gamma+ cells, whereas CD4+CCR7+ memory T cells showed higher coexpression of CXCR3. Expression of CCL21 was detected in both SF and synovial membranes. SF CD4+ memory T cells displayed significant migration to both inflammatory and homeostatic chemokines. CCR7+ T cells were detected in the synovial tissue in either diffuse perivascular lymphocytic infiltrates or organised lymphoid aggregates. In synovial tissue, a large fraction of CCR7+ cells co-localised with CXCR3, especially inside lymphoid aggregates, whereas CCR5+ cells were enriched in the sublining of the superficial subintima. In conclusion, CCR7 may have a role in the synovial recruitment of memory T cells in JIA, irrespective of the pattern of lymphoid organisation. Moreover, discrete patterns of chemokine receptor expression are detected in the synovial tissue.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/ar1485DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1065323PMC
December 2005

Coordination of activating and inhibitory signals in natural killer cells.

Mol Immunol 2005 Feb;42(4):477-84

Centre d'Immunologie de Marseille-Luminy, INSERM-CNRS-Université de la Méditerranée, Campus de Luminy, Case 906, 13288 Marseille Cedex 09, France.

NK cells are equipped with multiple activating and inhibitory cell surface receptors whose engagement regulate NK cell effector function (i.e. cytotoxicity as well as chemokine and cytokine production). Several components (adaptors, effector molecules) that participate to NK cell signalling pathways have been described. Yet, the spatio-temporal organisation of these pathways is still poorly understood. In addition, the mechanisms that integrate several simultaneous input signals in NK cells remain to be elucidated.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.molimm.2004.07.030DOI Listing
February 2005

Cytokine flexibility of early and differentiated memory T helper cells in juvenile idiopathic arthritis.

J Rheumatol 2004 Oct;31(10):2048-54

2nd Division of Pediatrics, "G. Gaslini" Scientific Institute for Children, Genoa, Italy.

Objective: It has been suggested that CD45RO+CD27+ T cells represent recently activated memory cells, whereas CD45RO+CD27- T cells are activated memory T cells in the process of differentiating into effector cells. We investigated (1) CCR7 and CCR5 expression and (2) modulation of cytokine expression in "early" (CD27+) and "differentiated" (CD27-) memory CD4+ T cells from peripheral blood and synovial fluid (SF) of patients with juvenile idiopathic arthritis (JIA).

Methods: SF CD4+CD45RO+CD27+ and CD27- memory T cells from 6 patients with JIA were tested by flow cytometry for intracellular interferon-gamma (IFN-gamma) and interleukin 4 (IL-4) after in vitro priming with CD3 and CD28 mAb in the presence of IL-4, and subsequent culture with IL-2.

Results: SF CD4+CD45RO+CD27+ cells contained higher proportions of CCR7+ (median 46% vs 23%) and lower proportions of CCR5+ (73% vs 90%) cells than paired CD27- T cells. Both CD27+ and CD27- memory T helper cells from SF displayed a higher IFN-gamma/IL-4 ratio than their peripheral blood counterparts. No significant difference was observed in the percentage of IFN-gamma-expressing cells between CD27+ (32%, range 4-47%) and CD27- (29.4%, range 5-52%) memory T helper cells from SF.

Conclusion: Irrespective of their differentiation stage, both CD27+ and CD27- SF memory T helper cells were found to switch from a proinflammatory to an antiinflammatory pattern of cytokine production.
View Article and Find Full Text PDF

Download full-text PDF

Source
October 2004

Peritoneal T cell responses can be polarized toward Th1 or Th2 in children on chronic peritoneal dialysis.

Artif Organs 2004 Aug;28(8):750-2

Nephrology Department, G. Gaslini Children's Hospital, Genoa, Italy.

Peritoneal T cell responses can be polarized toward Th1 or Th2 in children on chronic peritoneal dialysis. Previous studies on the peritoneal immune system described the presence of activated T lymphocytes in peritoneal effluents from subjects on chronic peritoneal dialysis (CPD). Since Th1/Th2 polarized response can influence the outcome of specific infectious diseases, we investigated if activated Th1/Th2 cells can be detected in peritoneal effluents during peritoneal dialysis, in order to better understand the role of T cells in the mechanisms of peritoneal defense. We have studied 8 children (4 males, 4 females, mean age 5.8 +/- 5.7 years, range 0.3-13.4) on CPD. Peritoneal cells have been isolated from peritoneal effluents by centrifugation. Immunofluorescent staining of intracellular cytokines for flow cytometric analysis was used to detect the percentage of T cells producing either IFN-gamma (Th1) or IL-4 (Th2). In the initial study 3 months after CPD initiation, high percentages of IFN-gamma positive peritoneal T cells (38% and 63%) were detected in two subjects; this finding is consistent with a Th1 polarization of peritoneal T cells. In another subject, high percentages of IL-4 positive T cells (31%) were detected, suggesting a Th2 polarization of peritoneal T cell response. Small amounts of either Th1 or Th2 T cells (2-4%) were also detected in the other subjects. At the 1 year follow-up, Th1 polarization persisted in one subject (18% IFN-gamma positive peritoneal T cells), in another a shift from Th1 to Th2 was observed, and in the other subject a down regulation of both T cell subsets occurred. The finding that a predominance of T cells producing either IFN-gamma or IL-4 was found in 3 out of 8 children strongly suggests that peritoneal T cell responses can be polarized toward Th1 or Th2. The decrease of Th1 and/or Th2 polarized T cells in the peritoneum of 4 out of 6 subjects (after 1 year) suggests that CPD can play an immunosuppressive role on T cell peritoneal responses. Further studies are needed in order to define whether different T helper activation patterns are associated with a higher risk of peritoneal infection or of peritoneal damage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1525-1594.2004.00055.xDOI Listing
August 2004

Changes in markers of bone turnover and inflammatory variables during alendronate therapy in pediatric patients with rheumatic diseases.

J Rheumatol 2002 Aug;29(8):1786-92

Clinica Pediatrica, ICP, Milano, Italy.

Objective: Alendronate treatment for 12 months in pediatric patients with rheumatic diseases and secondary low bone mass was reported to result in a substantial increase in bone mineral density (BMD). In this study, we evaluated the changes in bone metabolism and disease activity markers in 45 patients ages 5 to 18 years (31 female, 14 male) with rheumatic diseases treated with alendronate for 12 months.

Methods: Variables analyzed included demographic and anthropometric data, biochemical markers of bone metabolism, disease activity indexes, and BMD values. For all variables, the differences between levels at baseline and at 12 months were calculated; correlations between the variables and between the BMD variation over 12 months and baseline levels of the different variables were also evaluated.

Results: There was a statistically significant decrease of both bone resorption and bone formation markers over the 12 month treatment period. By contrast, no disease activity index changed significantly over one year. BMD Z score change over one year did not correlate with erythrocyte sedimentation rate, matrix metalloproteinase-3, interleukin 6, or C-reactive protein variations over the same period.

Conclusion: These results support the conclusion that alendronate treatment is accompanied by a reduction of bone turnover in pediatric patients and that the observed BMD increase is not secondary to a reduction of inflammatory activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
August 2002

A novel case of immunodeficiency, centromeric instability, and facial anomalies (the ICF syndrome): immunologic and cytogenetic studies.

Haematologica 2002 Mar;87(3):329-31

The immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome is characterized by hypogammaglobulinemia and recurrent bacterial infections. Here we report a novel case of ICF syndrome with hypogammaglobulinemia and an inverted CD4/CD8 ratio. Cytogenetically abnormal cells,that were identified in both CD4+ and CD4- peripheral blood lymphocytes, retained their ability to proliferate in vitro following polyclonal stimulation. A primitive defect of B-cell differentiation was detected.
View Article and Find Full Text PDF

Download full-text PDF

Source
March 2002