bluuebunny/crossref_metadata_2025 huggingface dataset:
Anti-platelet antibodies associated with the Canale–Smith syndrome bind to the same platelet glycoprotein complexes as those of idiopathic thrombocytopenic purpura patients
Authors: GRODZICKY T , BUSSEL J B , ELKON K B
Published: March 2003

The Canale–Smith syndrome (CSS) is an inherited disease characterized by massive lymphadenopathy, hepatosplenomegaly and systemic autoimmunity to erythrocytes and platelets. Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disease in which approximately 60–80% of patients have anti-platelet antibodies directed against specific platelet glycoprotein complexes (GPCs) located on their membrane: GP IIb/IIIa, GPIb/IX, and GPIa/IIa. Almost all (95–100%) of the antibody-positive patients have antibodies directed against GPIIb/IIIa alone, or in combination with other glycoprotein targets. Our objective was to determine the specificities of the anti-platelet antibodies in CSS patients. The detection of anti-platelet antibodies was performed using a commercially available ELISA, the Pak-AUTO (GTI, Brookfield, WI), in which highly purified GPIIb/IIIa, GPIb/IX, and GPIa/IIa are immobilized on microtitre plates, incubated with serum or plasma, and subsequently developed with an antihuman polyclonal immunoglobulin. Of 14 CSS patients tested, 11 (79%) had anti-platelet antibodies in their serum directed toward at least one of the three major GPC, nine (82%) of which were against GPIIb/IIIa alone or in combination. Antibodies detected in the sera of ITP patients had similar specificities. No such antibodies were detected in samples from 25 consecutive normal controls. These results demonstrate that a genetically defined defect in lymphocyte apoptosis results in a humoral autoimmune response with anti-platelet specificities very similar to the common idiopathic form of autoimmune thrombocytopenia.
The cytoplasmic linker protein CLIP-170 is a human autoantigen
Authors: GRIFFITH K J , RYAN J P , SENÉCAL J-L , FRITZLER M J
Published: March 2003

The purpose of this study was to identify autoantigens that are recognized by human sera and are associated with a speckled cytoplasmic fluorescent staining pattern on tissue culture cells, and to determine clinical features associated with specific autoantibodies. A serum from a patient with systemic lupus erythematosus was used to identify a 3·7-kb cDNA insert from a HeLa cell expression library. The purified cDNA (VLK2·1) encoded a peptide of 1051 amino acids that shared 98·4% similarity with the carboxyl terminal portion of a previously reported 170 kD protein named cytoplasmic linker protein-170 (CLIP-170). Antibodies affinity purified with the recombinant CLIP-170 protein, the prototype human serum and a monoclonal antibody raised against CLIP-170 exhibited identical speckled staining of the cytoplasm in HEp-2 cells. The human autoantibodies reacted with the purified recombinant protein in a Western immunoblot and immunoprecipitated the in vitro translated recombinant protein. Three additional human sera also immunoprecipitated the recombinant CLIP-170 protein. The clinical diagnoses in these patients were limited scleroderma, glioblastoma and idiopathic pleural effusion. This is the first report that identifies CLIP-170 as a human autoantigen.
Expression, modulation and signalling of IL-17 receptor in fibroblast-like synoviocytes of patients with rheumatoid arthritis
Authors: KEHLEN A , THIELE K , RIEMANN D , LANGNER J
Published: March 2003

Interleukin-17 (IL-17) has been characterized as a proinflammatory cytokine produced by CD4+ CD45RO+ memory T cells. Overproduction of IL-17 was detected in the synovium of patients with rheumatoid arthritis (RA) compared to patients with osteoarthritis. In contrast to the restricted expression of IL-17, the IL-17 receptor (IL-17R/CDw217) is expressed ubiquitously. Using a real-time RT-PCR assay, we detected similar absolute levels of IL-17R mRNA expression in fibroblast-like synoviocytes (SFC) from patients with RA (mean 9 pg/μg total RNA; ranged from 0·1 pg to 96 pg IL-17R mRNA/μg total RNA) compared to synoviocytes of non-RA patients. Analysis of the IL-17R surface expression confirmed the results obtained for IL-17R mRNA expression. Exposure of SFC to IL-17 led to a mRNA induction of CXC chemokines IL-8, GRO-α and GRO-β. An anti-IL-17 antibody blocked these effects of IL-17. The MAPK p38 appears necessary for the regulation of IL-8, GRO-α and GRO-β expression as shown by inhibition with SB203580. The inhibitors genistein (tyrosine kinase inhibitor) and calphostin C (inhibitor of protein kinase C) reduced significantly the IL-17-stimulated mRNA expression of IL-8, GRO-α and GRO-β in SFC, whereas PD98059 (inhibitor of MEK-1/2) was without effect. Pharmacological drugs used in therapy of RA, such as cyclosporin and methotrexate, induced a fourfold increase of IL-17R mRNA expression and augmented the IL-17-stimulated IL-8 expression. Our results support the hypothesis that IL-17/IL-17R may play a significant role in the pathogenesis of RA contributing to an unbalanced production of cytokines as well as participating in connective tissue remodelling.
Elevated monocytic IL-12 and TNF-αproduction in Wegener's granulomatosis is normalized by cyclophosphamide and corticosteroid therapy
Authors: LAMPRECHT P , KUMANOVICS G , MUELLER A , CSERNOK E , KOMOCSI A , TRABANDT A , GROSS W L , SCHNABEL A
Published: March 2003

Wegener's granulomatosis (WG) is characterized by a predominance of the type 1 T-helper cell (Th1) response. We have studied monocytic cytokine expression in untreated patients and in patients who did not respond to prior methotrexate or trimethoprim-sulphamethoxazole therapy, i.e. patients with active disease. Intracytoplasmic IL-12 and TNF-α expression was significantly increased in WG compared with healthy controls. IL-8 expression was not increased. Two and 12 weeks of daily standard oral cyclophosphamide and corticosteroid (CYC + GC) treatment induced a stable remission of the disease. Elevated IL-12 and TNF-α expression of monocytes was normalized. The active metabolite of CYC was shown to down-regulate IL-12 mRNA in vitro. Monocytic cytokines, especially IL-12, may have a role in the early determination and skewing of the immunoregulatory response towards a Th1 profile. It appears that CYC + GC exerts its effect by normalizing the Th1-driving cytokine pattern, and CYC may maintain this mode of action. Normalization of the skewed cytokine pattern may be a prerequisite and an indicator of inducing a remission in WG.
Highly active antiretroviral therapy restores in vitro mitogen and antigen-specific T-lymphocyte responses in HIV-1 perinatally infected children despite virological failure
Authors: PERUZZI M , AZZARI C , GALLI L , VIERUCCI A , DE MARTINO M
Published: March 2003

To analyse the effect of highly active antiretroviral therapy (HAART) on T-lymphocyte functions we selected seven HIV-1 perinatally infected children (CDC immunological category 1 or 2) who had neither a fall in their plasma HIV-1 RNA levels nor a significant rise in CD4+ lymphocyte counts while receiving HAART. Clinical signs and symptoms were monitored monthly. Plasma viral load, CD4+, CD8+, CD19+ lymphocyte counts and in vitro T-lymphocyte proliferative responses to mitogens (anti-CD3, phytohaemoagglutinin, concanavalin A and pokeweed mitogen) and recall antigens (Candida albicans and tetanus toxoid) were tested at baseline and after 1, 3, 6 and 12 months of HAART. Twenty-two healthy age-matched children were studied as controls. A gain in body weight, no worsening of the disease and no recurrence of opportunistic infections were observed. At baseline, the majority of the children had low responses to mitogens, and all of them had a defective in vitro antigen-specific T-lymphocyte response (<2 standard deviations below the mean result for controls). During HAART, a significant increase in the response to mitogens and antigens was observed in all the patients. The T-lymphocyte response was restored more consistently against antigens to which the immune system is constantly exposed (Candida albicans, baseline versus 12 months: P < 0·001) compared with a low-exposure antigen (tetanus toxoid, baseline versus 12 months: P < 0·01). HAART restores in vitro T-lymphocyte responses even in the absence of a significant viral load decrease and despite any significant increase in CD4+ lymphocyte counts. It implies that a direct mechanism might be involved in the overall immune recovery under HAART.
Transforming growth factor-β expression in human retinal pigment epithelial cells is enhanced by Toxoplasma gondii: a possible role in the immunopathogenesis of retinochoroiditis
Authors: NAGINENI C N , DETRICK B , HOOKS J J
Published: March 2003

Retinochoroiditis caused by Toxoplasma gondii infection results in inflammation and necrosis of the retina. We have used human retinal pigment epithelial cultures (HRPE) as an in vitro model to investigate the role of TGF-β in T. gondii-induced retinochoroiditis. RT-PCR analyses showed enhanced steady state levels of TGF-β1 and TGF-β2 mRNA in T. gondii-infected HRPE. Uninfected HRPE secrete TGF-β1 in a latent form while 10–30% of the secreted TGF-β2 was in the active form. T. gondii infection induced a significant increase (P < 0·01) in total TGF-β1 and TGF-β2 secretion by HRPE. In addition, soluble extracts of T. gondii (ST) stimulated secretion of both TGF-β1 and TGF-β2 significantly (P < 0·01). Interestingly, T. gondii infection as well as ST of the parasites completely inhibited secretion of the active form of TGF-β2. Studies evaluating the effect of TGF-β on T. gondii replication in HRPE revealed that TGF-β enhanced parasite replication. The interactions between host retinal cells and T. gondii may play an active role in the pathogenesis of retinochoroiditis.
Deficiencies in CD4+ and CD8+ T cell subsets in ataxia telangiectasia
Authors: SCHUBERT R , REICHENBACH J , ZIELEN S
Published: March 2003

Chronic sinopulmonary infections that are associated with immunodeficiency are one of the leading causes of death in the multi-systemic disease ataxia telangiectasia (AT). Immunological investigations of AT patients revealed a broad spectrum of defects in the humoral and the cellular immune system. Based on their important role in host defence the aim of our study was an extensive analysis of cell distribution and function of CD4+ and CD8+ T lymphocytes and NK cells. We found that naive (CD45RA+) CD4+ lymphocytes, as well as CD8+/CD45RA+ lymphocytes, are decreased, whereas NK cells (CD3−/CD16+CD56+) are significantly elevated in AT patients. In our culture system proliferation and cytokine production was normal in purified memory (CD45RO+) lymphocytes after stimulation with phorbol-12,13-dibutyrate (PBu2) and after PHA activation, indicating that differences in proliferation and cytokine production are due solely to reduced numbers of CD45RA+ lymphocytes. However, activation, and especially intracellular interferon production of AT lymphocytes, seem to follow different kinetics compared to controls. In contrast to polyclonal activation, stimulation via the T cell receptor results consistently in a reduced immune response. Taken together, our results suggest that deficiency of immunocompetent cells and an intrinsic immune activation defect are responsible for the immunodeficiency in AT.
Diversity and dynamics of the T-cell response to MBP in DR2+ve individuals
Authors: MAZZA G , PONSFORD M , LOWREY P , CAMPBELL M J , ZAJICEK J , WRAITH D C
Published: March 2003

It is generally accepted that multiple sclerosis (MS) is mediated by autoreactive T cells and that myelin basic protein (MBP) is one of the target autoantigens. The T-cell response to MBP has been analysed extensively, largely through the use of T-cell lines (TCL) and T-cell clones (TCC), and to date, three immunodominant regions (13–32, 84–103 and 144–163) have been described. However, given that TCL may represent a skewed pattern of peptide reactivity, we have developed a kinetic response assay in which the proliferation of peripheral blood mononuclear cells (PBMC) from MS patients and healthy individuals was measured directly against a panel of peptides spanning the full length of human MBP. Furthermore, PBMC from each subject were tested three times over the course of 18 months. A high proportion of MS patients exhibited a significant response to eight MBP regions (1–24, 30–54, 75–99, 90–114, 105–129, 120–144, 135–159 and 150–170). TCC were subsequently generated from MS subjects and were used to further define the epitope recognized in each case. Overall, normal individuals recognized significantly fewer peptides. In addition, we noted that the T-cell recognition of any one peptide can fluctuate, appearing at one time point, regressing, and subsequently reappearing at a later date. This study provides new insight into the recognition profile and dynamics of myelin-antigen-specific T cells in MS.
Longitudinal study of intracellular T cell cytokine production in infants compared to adults
Authors: BUCK R H , CORDLE C T , THOMAS D J , WINSHIP T R , SCHALLER J P , DUGLE J E
Published: March 2003

Intracellular cytokine production in lymphocytes obtained longitudinally from 325 healthy infants aged 2–12 months was compared with adult lymphocytes using four-colour flow cytometry. Peripheral blood samples (180 microlitres) were stimulated with phorbol 12-myristate 13-acetate, ionomycin and brefeldin A to induce production and intracellular accumulation of cytokines. The method was validated by assessing reproducibility, repeatibility, ruggedness (i.e. fresh versus day-old blood samples), precision, linearity and sensitivity. Among infants, the number and percentage of T lymphocytes (helper/inducer T cell subsets and cytotoxic/suppressor T cell subsets) producing IFN-γ (type 1) and IL4 (type 2) increased over the first year of life but remained significantly lower than levels found in adults. In both infants and adults more CD4− T cells than CD4+ T cells were induced to make IFN-γ. Infant Th1/Th2 ratios revealed modest Th1-skewed (predominant) profiles compared to adults, which were 5–10 times higher. Infant Tc1/Tc2 ratios revealed Tc1-skewed responses which were equal to adult ratios by age 12 months. At 12 months infant Th2 responses were closer to adult levels than were Th1 cells. Intracellular cytokine detection by flow cytometry is a rapid, sensitive, rugged and precise method to characterize immune status changes over time.
Requirement for TNF-Tnfrsf1 signalling for sclerosing cholangitis in mice chronically infected byCryptosporidium parvum
Authors: PONNURAJ E M , HAYWARD A R
Published: March 2003

An increase in mRNA levels for TNF and Tnfrsf1 in the bile ducts of Tnfsf5–/–(CD40 ligand or CD154 knockout) mice developing cholangitis following infection by Cryptosporidium parvum (CP) is accompanied by staining for TNFα in areas of inflammation. To determine whether TNF contributed to the bile duct damage seen in chronically-infected animals, we bred B6 mice with disrupted genes for Tnfrsf1a, Tnfrsf1b and Tnfsf5. Following CP infection, the Tnfsf5–/– Tnfrsf1a & 1b–/– mice were spared from cholangitis, even though their intestinal and bile duct infection by CP persisted. Mice with disruptions of Tnfsf5, and either Tnfrsf1a or Tnfrsf1b, developed bile duct sclerosis similar to that seen in CD40 and Tnfsf5 knockouts. Our data indicate that signalling through either TNF receptor is sufficient for the bile duct damage that follows chronic CP infection in mice, with disruption of the Tnfsf5 molecule.
Leptin receptor (Ob-R) expression is induced in peripheral blood mononuclear cells byin vitroactivation andin vivoin HIV-infected patients
Authors: SÁNCHEZ-MARGALET V , MARTÍN-ROMERO C , GONZÁLEZ-YANES C , GOBERNA R , RODRÍGUEZ-BAÑO J , MUNIAIN M A
Published: March 2003

Leptin, the Ob gene product, is an adipocyte hormone that centrally regulates weight control. In addition, other effects of leptin in peripheral tissues have been described. Thus, leptin has been found to regulate reproduction, haematopoiesis and immune function. We have found recently that leptin has a stimulatory effect on human peripheral blood mononuclear cells (PBMC). Monocytes are activated by leptin alone whereas T lymphocytes need a suboptimal stimulus of PHA or ConA before further activation by leptin. These effects are mediated by the long isoform of the leptin receptor, which has been shown to trigger signalling in PBMC. In fact, we have found that human leptin stimulates Janus kinase (JAK)-signal transducer and activator of transcription (STAT), phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways in PBMC. In order to assess possible regulation of the long isoform of the leptin receptor (Ob-R) in mononuclear cells upon activation, we have studied the expression of Ob-R by RT-PCR and Western blotting in PBMC activated in vitro by PHA or ConA and in vivo in HIV-infected patients. We have found that in vitro activation and in vivo HIV infection correlates with an increase in leptin receptor expression in PBMC. Moreover, the leptin receptor is tyrosine phosphorylated in PBMC from HIV-infected patients, suggesting that the leptin receptor is activated. These results are consistent with the suggested role of leptin in modulating the immune response.
Interferon-αinduces interleukin-18 binding protein in chronic hepatitis C patients
Authors: KASER A , NOVICK D , RUBINSTEIN M , SIEGMUND B , ENRICH B , KOCH R O , VOGEL W , KIM S H , DINARELLO C A , TILG H
Published: March 2003

Interleukin-18 (IL-18), derived from macrophages and Kupffer cells, is the central pro-inflammatory cytokine leading to experimental liver failure. IL-18 binding protein (IL-18BP) is a circulating protein that binds IL-18 and neutralizes its activity. Since IL-18 production is increased in chronic HCV infection, we asked whether IFN-α might act on the IL-18/IL-18BP system in HCV patients. IL-18BP, total and free IL-18 plasma levels were determined in 13 HCV patients receiving 1 × 107 IU IFN-α subcutaneously daily for 28 days. The in vitro effects of IFN-α on macrophage IL-18BP and IL-18 were studied by enzyme-linked immunosorbent assays and Northern analysis. IFN-α administration increased IL-18BP plasma levels 3·24 fold 24 h after institution of therapy, resulting in a 67·4% reduction of free IL-18. Total IL-18 levels decreased from day +24 on. In vitro, IFN-α diminished IL-18 release from macrophages of healthy volunteers and chronic HCV patients. On top of its inhibitory effects on IL-1 and TNF-α release, IFN-α also exerts its anti-inflammatory action in vivo by induction of IL-18BP. These anti-inflammatory properties might account – together with its antiviral action – for its clinical efficacy in chronic hepatitis C.
Novel promiscuous HLA-DQ HIV Nef peptide that induces IFN-γ-producing memory CD4+T cells
Authors: PANCRÉ V , GEORGES B , ANGYALOSI G , CASTELLI F , DELANOYE A , DELACRE M , HACHULLA E , MAILLERE B , BOUZIDI A
Published: March 2003

We describe the highly conserved sequence 56–68 of the HIV Nef protein as the first promiscuous HLA-DQ HIV-derived peptide. The Nef peptide exhibits an albeit rare capacity to bind 6 different HLA-DQ molecules whereas no binding is observed with the 10 HLA-DR molecules tested. In agreement with these data, after immunization with the Nef peptide, HLA-DQ transgenic Aβ° mice display a vigorous cellular and humoral response while the specific immune response of HLA-DR expressing mice is minimal. The promiscuous potentiality of the Nef 56–68 peptide in humans has been confirmed by ex vivo immunization experiments with CD4+ T cells from 14 healthy donors expressing different HLA genotypes. Nef 56–68 specific CD4+ T cells rapidly acquire a memory cell phenotype and are characterized by the preferential usage of the TCR Vβ 6·1 gene segment and predominant production of IFN-γ. Taken together, these data indicate that the Nef 56–68 peptide constitutes an attractive component of vaccines aiming at inducing or enhancing HIV-specific T cell immunity.
Intranasal delivery of a truncated recombinant human SP-D is effective at down-regulating allergic hypersensitivity in mice sensitized to allergens ofAspergillus fumigatus
Authors: STRONG P , REID K B M , CLARK H
Published: March 2003

C57BL/6 mice were sensitized to Aspergillus fumigatus 1-week culture filtrate, which is rich in the non-glycosylated allergen Asp f1, a major allergen in allergic bronchopulmonary aspergillosis (ABPA). A comparison of the effect of treatment of allergen challenged mice by intranasal administration of a 60-kDa truncated recombinant form of human SP-D (rfhSP-D) or recombinant full length SP-A (rhSP-A) was undertaken. Treatment with rfhSP-D produced significant reduction in IgE, IgG1 and peripheral blood eosinophilia and treatment with rfhSP-D, but not rhSP-A resulted in a significant reduction in airway hyperresponsiveness as measured by whole body plethysmography. Lung histology revealed less peribronchial lymphocytic infiltration in mice treated with rfhSP-D. Intracellular cytokine staining of spleen homogenates showed increases in IL-12 and IFN-γ and decrease in IL-4. The level of endogenous mouse SP-D was elevated sixfold in the lungs of sensitized mice and was not affected by treatment with rfhSP-D. Taken with our previous studies, with a BALB/c mouse model of ABPA using a 3-week A. fumigatus culture filtrate, the present results show that rfhSP-D can suppress the development of allergic symptoms in sensitized mice independent of genetic background and using a different preparation of A. fumigatus allergens.
Inhibition of experimental autoimmune uveoretinitis by systemic and subconjunctival adenovirus-mediated transfer of the viral IL-10 gene
Authors: DE KOZAK Y , THILLAYE-GOLDENBERG B , NAUD M-C , VIANA DA COSTA A , AURIAULT C , VERWAERDE C
Published: March 2003

Pathological ocular manifestations result from a dysregulation in the balance between proinflammatory type 1 cytokines and regulatory type 2 cytokines. Interleukin-10 (IL-10) is an anti-inflammatory cytokine with potent immunosuppressive effects. We have examined the efficiency of viral IL-10 adenovirus (Ad-vIL-10)-mediated gene transfer on experimental autoimmune uveoretinitis (EAU) induced in mice and rats by purified retinal autoantigens, respectively, interphotoreceptor binding protein (IRBP) and S-antigen (S-Ag). B10-A mice that received a single unilateral injection of Ad-vIL-10 in the retro-orbital sinus venosus performed 1 day before immunization with IRBP in the footpads showed high levels of circulating vIL-10 in their sera and a significant reduction in pathological ocular manifestations. Lower levels of IFN-γ and IL-2 were found in cellular supernatants from IRBP-stimulated splenic cells in these treated mice. The local effect on ocular disease of vIL-10 was neutralized completely by injection of a monoclonal anti-vIL-10 antibody, demonstrating the specificity of the treatment. To determine whether the transfer of the vIL-10 gene within the periocular tissues of the eye could prevent acute EAU, a subconjunctival injection of Ad-vIL-10 was performed in Lewis rats simultaneously with S-­antigen in the footpads. This injection determined in situ vIL-10 expression with very low circulating vIL-10 and led to a significant reduction of EAU without affecting the systemic immune response. The present results suggest that Ad-mediated gene transfer resulting in systemic and local expression of vIL-10 provide a promising approach for the treatment of uveitis.
The scavenger receptor, cysteine-rich domain-containing molecule gp-340 is differentially regulated in epithelial cell lines by phorbol ester
Authors: KANG W , NIELSEN O , FENGER C , MADSEN J , HANSEN S , TORNOE I , EGGLETON P , REID K B M , HOLMSKOV U
Published: March 2003

Gp-340 is a glycoprotein belonging to the scavenger receptor cysteine rich (SRCR) group B family. It binds to host immune components such as lung surfactant protein D (SP-D). Recent studies found that gp-340 interacts directly with pathogenic microorganisms and induces their aggregation, suggesting its involvement in innate immunity. In order to investigate further its potential immune functions in the appropriate cell lines, the expression of gp-340 in four conventional immune cell lines (U937, HL60, Jurkat, Raji), and two innate immune-related epithelial cell lines (A549 derived from lung and AGS from stomach), was examined by RT-PCR and immunohistochemistry. The resting immune cell lines showed weak or no gp-340 mRNA expression; while the two epithelial cell lines expressed gp-340 at much higher level, which was differentially regulated by phorbol myristate acetate (PMA) treatment. In the A549 cells, gp-340 was up-regulated along with the PMA-induced proinflammatory expression of both IL-6 and IL-8. In AGS cells, PMA down-regulation of gp-340 was seen in parallel with an up-regulation of the two mature gastric epithelial specific proteins TFF1 (trefoil factor 1) and TFF2, which are implicated as markers of terminal differentiation. Analysis of the distribution of gp-340, together with the TFFs and SP-D in normal lung and gastric mucosa, supported further our in vitro data. We conclude that the differential regulation of gp-340 in the two epithelial cell lines by PMA indicates that gp-340 s involvement in mucosal defence and growth of epithelial cells may vary at different body locations and during different stages of epithelial differentiation.
Interleukin-10 ameliorates the outcome ofStaphylococcus aureusarthritis by promoting bacterial clearance
Authors: GJERTSSON I , HULTGREN O H , TARKOWSKI A
Published: March 2003

Staphyllococcus aureus-induced infections often result in high mortality and permanent joint destruction, despite treatment with antibiotics. IL-10 is typically regarded as an anti-inflammatory cytokine because it promotes a T helper cell type 2 response, and subsequently down-regulates cell mediated immune functions. To investigate the role of IL-10 in S. aureus-induced arthritis and sepsis, Balb/c mice, intact or defective with respect to IL-10 gene were intravenously inoculated with bacteria. IL-10–/– mice develop a more frequent and destructive arthritis compared to their congeneic controls. The mechanisms regulating such outcome may be due not only to the anti-inflammatory properties of IL-10 but also, directly or indirectly, to antibacterial features of this molecule. Indeed, inoculation of staphylococci to IL-10–/– mice resulted in higher bacterial load in blood and kidneys compared to congeneic controls. Altogether our data indicate that IL-10 is essential for efficient elimination of bacteria and thereby for protection against septic arthritis.
Hyper IgD syndrome (HIDS) associated with in vitro evidence of defective monocyte TNFRSF1A shedding and partial response to TNF receptor blockade with etanercept
Authors: ARKWRIGHT P D , MCDERMOTT M F , HOUTEN S M , FRENKEL J , WATERHAM H R , AGANNA E , HAMMOND L J , MIRAKIAN R M , TOMLIN P I , VIJAYDURAI P I , CANT A J
Published: March 2003

Hereditary periodic fever syndromes comprise a group of distinct disease entities linked by the defining feature of recurrent febrile episodes. Hyper IgD with periodic fever syndrome (HIDS) is caused by mutations in the mevalonate kinase (MVK) gene. The mechanisms by which defects in the MVK gene cause febrile episodes are unclear and there is no uniformly effective treatment. Mutations of the TNFRSF1A gene may also cause periodic fever syndrome (TRAPS). Treatment with the TNFR-Fc fusion protein, etanercept, is effective in some patients with TRAPS, but its clinical usefulness in HIDS has not been reported. We describe a 3-year-old boy in whom genetic screening revealed a rare combination of two MVK mutations producing clinical HIDS as well as a TNFRSF1A P46L variant present in about 1% of the population. In vitro functional assays demonstrated reduced receptor shedding in proband's monocytes. The proband therefore appears to have a novel clinical entity combining Hyper IgD syndrome with defective TNFRSF1A homeostasis, which is partially responsive to etanercept.
Induction of IL-15 by TCR/CD3 aggregation depends on IFN-γand protects against apoptosis of immature thymocytesin vivo
Authors: Matthys P , DOOMS H , ROTTIERS P , MITERA T , OVERGERGH L , LECLERCQ G , BILLIAU A , GROOTEN J
Published: March 2003

TCR/CD3 aggregation by injection of anti-CD3 Ab produces T cell activation, release of cytokines such as IFN-γ, and apoptosis in the cortical region of the thymus. We show that anti-CD3 Ab induces IL-15 mRNA in spleens of wild-type but not IFN-γ receptor-knock-out (IFN-γR KO) mice. The loss of IL-15 mRNA induction in IFN-γR KO mice was associated with increased thymocyte apoptosis. Pretreatment of wild-type mice with neutralizing anti-IL-15 Ab increased the anti-CD3-triggered thymocyte apoptosis, thus mimicking the sensitive phenotype of IFN-γR KO mice. Inversely, anti-CD3-induced apoptosis in IFN-γR KO mice was suppressed by administration of recombinant IL-15. In IFN-γR KO mice and in wild-type mice that were treated with anti-IL-15, augmented apoptosis affected mainly CD4+CD8+ immature thymocytes. IL-15 as well as IL-15Rα mRNA expression in thymocytes was not increased by anti-CD3. These data demonstrate that systemic IL-15 exerts anti-apoptotic activity on immature T cells and establish a regulatory mechanism whereby TCR/CD3 engagement induces IL-15 expression via an IFN-γ-dependent pathway. The self-amplifying nature of this IFN-γ/IL-15 connection may constitute a regulatory pathway in central tolerance to self.
Detection and identification of a soy protein component that cross-reacts with caseins from cow's milk
Authors: ROZENFELD P , DOCENA G H , AÑÓN M C , FOSSATI C A
Published: March 2003

Soy-based formulas are the most employed cow's milk substitutes in the treatment of cow's milk allergy in our country. Since adverse reactions have been reported in allergic patients as a consequence of exposure to soy proteins, we have investigated the possible cross-reactivity between components from soybean and cow's milk. A cow's milk specific polyclonal antiserum and casein specific monoclonal antibodies were used in immunoblotting and competitive ELISA studies to identify a 30-kD component from soybean that cross-reacts with cow's milk caseins. Its IgE binding capacity was tested by EAST, employing sera from cow's milk allergic patients, not previously exposed to soy proteins. The 30 kD protein was isolated and partially sequenced. It is constituted by two polypeptides (A5 and B3) linked by a disulphide bond. The protein's capacity to bind to the different antibodies relies on the B3 poly-peptide. These results indicate that soy-based formula, which contains the A5-B3 glycinin molecule, could be involved in allergic reactions observed in cow's milk allergic patients exposed to soy-containing foods.
Development of CD4+ T cell lines that suppress an antigen-specific immune responsein vivo
Authors: VIEIRA DE MORAES L , SUN B , RIZZO L V
Published: March 2003

It has been suggested for many years that the regulation of the immune system for the maintenance of peripheral tolerance may involve regulatory/supressor T cells. In the past few years, several investigators have demonstrated that these cells can be generated in vitro. It has also been shown that they can inhibit the progression of various autoimmune disease models when infused into susceptible mice. We have generated two murine T cell lines in the presence of KLH-specific T cell clones from BALB/c or DBA2 mice. The lines are characterized by a low proliferative response to mitogens, the capacity to secrete high amounts of IL-10 and TGF-β, and small amounts of IFN-γ. Interestingly, these cells are unable to produce IL-2, IL-4 or IL-5. The study of the surface phenotype of both lines revealed CD4+, CD25high, CD44low and CTLA-4– cells. When injected intravenously in (CBy.D2) F1 mice, these cells were able to inhibit 50–100% of the TNP-specific antibody production, when the hapten was coupled to KLH. In the present study we offer another evidence for the existence of regulatory T cells in the T lymphocyte repertoire, suggesting that they can also regulate immune responses to foreign antigens. Furthermore, we demonstrate an alternative pathway to generate these cells different from approaches used thus far.
After chemotherapy, functional humoral response capacity is restored before complete restoration of lymphoid compartments
Authors: ZANDVOORT A , LODEWIJK M E , KLOK P A , BREUKELS M A , RIJKERS G T , TIMENS W
Published: March 2003

Chemotherapy has, besides the beneficial effects, several adverse effects. Suppression of the immune system is one of the most important problems. Infections caused by encapsulated bacteria like Streptococcus pneumoniae are responsible for a major part of infectious problems during and after treatment. The splenic marginal zone is essential in the initiation of an immune response to encapsulated bacteria. In this study, we analysed the effects of three different cytostatic agents on humoral immune responses. We found a reduced, but detectable immune response capacity at two days after treatment although the marginal zone B cell population is severely reduced at this time point. Twenty-four days after cessation of treatment, the immune response capacity was largely restored although lymphoid compartments were still not completely restored at that time point. Apparently, the presence of only few marginal zone B cells is sufficient to evoke a rise in antibody titres and although antibody titre increases are low, even small rises are most likely clinically relevant.
Regulation of the interleukin-5 receptorα-subunit on peripheral blood eosinophils from healthy subjects
Authors: HELLMAN C , HALLDÉN G , HYLANDER B , LUNDAHL J
Published: March 2003

The aim was to study in vitro regulation of the IL-5 receptor α (IL-5Rα) on purified peripheral blood eosinophils from healthy subjects. The IL-5Rα was down-regulated, in a dose-dependent manner, by recombinant IL-5 and GM-CSF, with IL-5 being most potent. This down-regulation was not induced by autocrine release of GM-CSF or IL-5, respectively. Incubation of eosinophils with cell-free peritoneal dialysis fluid (PF) collected from a patient with peritoneal fluid eosinophilia (PFE), induced up-regulation of the proportion of CD69 positive eosinophils, in parallel with down-regulation of the proportion of IL-5Rα positive eosinophils. Experiments with neutralizing antibodies against IL-5 and GM-CSF, revealed that IL-5 was the principal cytokine responsible for the down-regulation of the IL-5Rα. When eosinophils were incubated with PF collected from the same patient in remission or with PF collected from a newly started patient or a patient with bacterial peritonitis, less down-regulation of the IL-5Rα was observed.

In conclusion our data indicate that IL-5, as opposed to its proposed action on eosinophil progenitors, down-regulates the IL-5Rα chain on mature eosinophils. We therefore suggest that an IL-5 driven inflammation generates an eosinophil tissue phenotype that is characterized by a low IL-5Rα expression. These aspects of IL-5 action on IL-5Rα expression could gain new insights into the mechanisms of specific immuno-modulatory therapies, such as anti-IL-5.
Modulation of autoreactive responses of peripheral blood lymphocytes of patients with systemic lupus erythematosus by peptides based on human and murine anti-DNA autoantibodies
Authors: STHOEGER Z M , DAYAN M , TCHERNIACK A , GREEN L , TOLEDO S , SEGAL R , ELKAYAM O , MOZES E
Published: March 2003

Two peptides, based on the sequences of the complementarity-determining regions (CDR) 1 and 3 of a pathogenic murine monoclonal anti-DNA autoatibody that bears the 16/6 idiotype (Id), were shown to either prevent or treat an already established systemic lupus erythematosus (SLE) in two murine models of lupus. Two additional peptides based on the human monoclonal anti-DNA, 16/6 Id were synthesized. This study was undertaken in order to investigate the ability of the CDR-based peptides to immunomodulate SLE-associated responses of peripheral blood lymphocytes (PBL) of SLE patients. PBL of 24 of the 62 SLE patients tested proliferated in vitro following stimulation with the human 16/6 Id. Peptides based on the CDRs of both the human and murine anti-DNA autoantibodies inhibited efficiently and specifically the 16/6 Id-induced proliferation and IL-2 production. The latter inhibitions correlated with an up-regulated production (by 2·5–3·5-fold) of the immunosuppressive cytokine, TGF-β. Overall, the results of our study demonstrate that the CDR-based peptides are capable of down-regulating in vitro autoreactive T cell responses of PBL of SLE patients. Thus, these peptides are potential candidates for a novel specific treatment of SLE patients.
Human immunodeficiency virus-1 envelope glycoproteins and anti-CD4 antibodies inhibit interleukin-2-induced Jak/STAT signalling in human CD4 T lymphocytes
Authors: KRYWORUCHKO M , PASQUIER V , THèZE J
Published: March 2003

Human immunodeficiency virus (HIV) infection leads to a profound T cell dysfunction well before the clinical onset of acquired immunodeficiency syndrome (AIDS). We have been accumulating evidence that one of the mechanisms responsible for this T cell deficiency may be the dysregulation of signal transduction via the interleukin (IL)-2/IL-2 receptor (R) complex. In CD4 T cells, we have observed previously that viral envelope (env) glycoproteins induce IL-2 unresponsiveness and the down-regulation of the three chains making up the IL-2R (α, β, γ) in vitro. We have now established further that this disruption of the IL-2/IL-2R system manifests itself in defective signal propagation via the Janus kinase (Jak)/signal transducer and activator of transcription (STAT) pathway in response to IL-2. The treatment of CD4 T cells with HIV env or surface ligation of CD4 with anti-CD4 monoclonal antibodies inhibited the IL-2-induced activation of Jak-1 and Jak-3, as well as their targets, STAT5a and STAT5b. This Jak/STAT deficiency may contribute to the crippling of CD4 T cell responses to a cytokine central to the immune response by HIV.
Complement resistance of human carcinoma cells depends on membrane regulatory proteins, protein kinases and sialic acid
Authors: DONIN N , JURIANZ K , ZIPOREN L , SCHULTZ S , KIRSCHFINK M , FISHELSON Z
Published: March 2003

Nucleated cells employ several strategies to evade killing by homologous complement. We studied complement resistance in the human carcinoma cell lines (CA) T47D (mammary), SKOV3 (ovarian), and PC-3 (prostate) with emphasis on the following mechanisms of defense: 1. Expression and shedding of the membrane complement regulatory proteins (mCRP) CD46, CD55 and CD59; 2. Resistance based on protein phosphorylation; 3. Cell surface expression of sialic acid residues; 4. Desensitization to complement upon exposure to sublytic complement doses. Anti-mCRP antibody blocking experiments demonstrated that CD59 is the main mCRP protecting these CA from complement. Soluble CD59 was also found in supernates of PC-3> SKOV3 > T47D cells. Second, inhibitors of PKC, PKA and MEK sensitized the CA to lysis, thus implicating these protein kinases in CA complement resistance. Third, removal of sialic acid residues with neuraminidase also sensitized CA to lysis. Finally, exposure of CA to sublytic doses of complement conferred on them enhanced resistance to lytic complement doses in a PKC-dependent process. Combined treatment of CA with anti-CD59 antibodies, PD98059 (a MEK inhibitor) and neuraminidase produced a large enhancement in CA sensitivity to complement. Our results show that CD59 and sialic acid residues present on the cell surface, and intracellular processes involving protein phosphorylation act additively to secure CA resistance to complement-mediated lysis. Therefore, the effectiveness of antibody- and complement-based cancer immunotherapy will markedly improve by suppression of the various complement resistance mechanisms.
Signal transducer and activator of transcription 6 geneG2964Apolymorphism and inflammatory bowel disease
Authors: XIA B , CRUSIUS J B A , WU J , ZWIERS A , VAN BODEGRAVEN A A , PEñA A S
Published: March 2003

Signal transducer and activator of transcription 6 (STAT6) is a key transcription factor involved in interleukin 4 (IL-4) and IL-13-mediated Th2 response. The STAT6 gene is located on chromosome 12q13.3–14·1 (IBD2 region) and is therefore a positional and functional candidate gene for study in inflammatory bowel disease. We investigated the G2964A polymorphism in the 3′ untranslated region of the STAT6 gene in Dutch patients with inflammatory bowel disease and healthy controls. The G2964A polymorphism in the STAT6 gene was genotyped in 141 unrelated Dutch Caucasian patients with ulcerative colitis, 183 patients with Crohn's disease and 173 healthy individuals by PCR and the amplification-created restriction site method. Patients with Crohn's disease were classified according to the Vienna classification and the patients with ulcerative colitis were classified with the age at onset, extent of disease and colectomy. We did not find significant differences in genotype and allele frequencies of the G2964A polymorphism in the STAT6 gene between ulcerative colitis, Crohn's disease and healthy controls. Subgroups of the patients with Crohn's disease classified according to the Vienna classification and those with ulcerative colitis classified according to age of onset, disease extension and colectomy did not differ in the distribution of this polymorphism. The STAT6 G2964A gene polymorphism is not involved in the overall susceptibility or in determining the phenotype of IBD.
Familial isolated primary hyperparathyroidism with parathyroid carcinomas: clinical and molecular features
Authors: Yoshimoto Katsuhiko , Endo Hideko , Tsuyuguchi Masaru , Tanaka Chisato , Kimura Takehiko , Iwahana Hiroyuki , Kato Genichi , Sano Toshiaki , Itakura Mitsuo
Published: March 2003

OBJECTIVE

Familial isolated primary hyperparathyroidism (FIHP) is a rare hereditary disorder. We present four patients from a single family with FIHP, and genetic analysis of their parathyroid adenomas and parathyroid carcinoma.

DESIGN

DNA was extracted from tumours resected at surgery. Tumours were examined for loss of heterozygosity (LOH) with microsatellite polymorhpic markers.

PATIENTS

The 27‐year‐old proband (Patient 1) died of parathyroid carcinoma with metastases to the lungs and chest wall. Sixteen years later, his 34‐year‐old sister (Patient 2) presented with a neck tumour and primary hyperparathyroidism. Family screening revealed parathyroid tumours in his 36‐year‐old sister (Patient 3) and 29‐year‐old cousin (Patient 4). Histological examination of resected tumours showed parathyroid carcinoma and adenoma in Patient 2, a parathyroid adenoma in Patient 3, and an atypical parathyroid adenoma in Patient 4. Autopsy of the proband ruled out multiple endocrine neoplasia (MEN) type 1, and the three patients who underwent parathyroidectomy did not exhibit any abnormalities in the pancreas or the pituitary gland.

RESULTS

Analysis of tumour DNA from one parathyroid carcinoma (Patient 2), the atypical parathyroid adenoma (Patient 4), and two parathyroid adenomas (Patients 2 and 3) showed limited LOH on chromosomes 13q12.3–q32 in an adenoma of Patient 2 and 9p21–p22 and 13q12.3–q32 in an adenoma of Patient 3.

CONCLUSION

These results suggest the possible contribution of tumour suppressor genes including the retinoblastoma gene and the hereditary breast cancer susceptibility gene (BRCA2) on 13q to parathyroid tumours in this family.
Evidence for a role of intracellular stored parathyroid hormone in producing hysteresis of the PTH–calcium relationship in normal humans
Authors: Schwarz Peter , Madsen Jesper C. , Rasmussen Anne Q. , Transbøl Lb , Brown Edward M.
Published: March 2003

OBJECTIVE

Despite the clear recognition that extracellular ionized calcium controls PTH secretion, there have been suggestions of hysteresis in the relationship between extracellular ionized calcium and PTH during recovery from induced hypo‐ and hypercalcaemia in vivo in humans. In this study, we examined the possibility that release of intracellular stored PTH during induced hypocalcaemia may explain hysteresis.

VOLUNTEERS

Eleven volunteers, five women and six men, were recruited to participate in the study.

DESIGN

A series of three protocols of repeated induction of hypocalcaemia or sequential induction of hypo‐ and hypercalcaemia.

RESULTS

We observed in a total of 13 trials that a drastic lowering of blood ionized calcium by 0.20 mmol/l within 30 min elicited an immediate large, transient peak release of PTH amounting to 6–16 times the baseline concen_tration. However, following a steady‐state period of hypocalcaemia, a subsequent lowering of blood ionized calcium either following a brief return to normocalcaemia (protocol 1), from the initial hypocalcaemic level of blood ionized calcium (protocol 2) or after a brief period of induced hypercalcaemia (protocol 3) gave either no peak release of PTH or a markedly blunted peak. Thus, the PTH response during the initial induction of and the first recovery from hypocalcaemia in our protocol 3 showed significant hysteresis in the relationship between blood ionized calcium and PTH (P < 0.001), whereas, no hysteretic relationship could be shown during the second recovery from induced hypocalcaemia in four of five cases (NS). Moreover, no hysteretic relationship was observed during induction, recovery and re‐induction of hypercalcaemia in protocol 3 (NS).

CONCLUSION

We believe that the release of what might be preformed, intracellular stored depot PTH can explain, at least in part, the observed hysteretic PTH–calcium relationship in normal humans.