bluuebunny/crossref_metadata_2025 huggingface dataset:
A comparison of the T cell delayed-type hypersensitivity epitopes of the 19-kD antigens fromMycobacterium tuberculosisandMyco. intracellulareusing overlapping synthetic peptides
Authors: MACKALL J C , BAI G H , ROUSE D A , ARMOA G R G , CHUIDIAN F , NAIR J , MORRIS S L
Published: August 2010

Mycobacterial disease remains a serious international public health concern. Improved methods to rapidly and specifically detect mycobacterial infections would greatly enhance clinical management of these diseases. To define species-specific T cell epitopes that may be useful for the immunodiagnosis of mycobacterial infections, polymerized synthetic peptides from the 19-kD Mycobacterium tuberculosis and Myco. intracellulare protein homologues were tested in guinea pig DTH assays. Five Myco. tuberculosis and eight Myco. intracellulare peptides evoked skin test responses. Although all of the active Myco. tuberculosis and seven of the Myco. intracellulare peptides elicited non-specific DTH reactions, the peptide IN13 induced a Myco intracellulare-specific skin test reaction, and thus represents a specific Myco intracellulare T cell DTH epitope. This result suggests that the development of monospecific peptide-based immunodiagnostic reagents may be feasible for future clinical use.
Production of IL-1 and IL-1 receptor antagonist and the pathological significance in lipopolysaccharide-induced arthritis in rabbits
Authors: MATSUKAWA A , OHKAWARA S , MAEDA T , TAKAGI K , YOSHINAGA M
Published: August 2010

Injection of lipopolysaccharide (LPS) into rabbil knee joints provoked leucocyte infiltration and loss of proteoglycan (PG) from the cartilage. We investigated the role of IL-1 and IL-1 receptor antagonist (IL-IRa) and its significance in the pathogenesis of LPS-arthritis. Production of IL-1β peaked at 6 h (196.7±89.4 pg/joint) after injection of 10 ng of LPS. while IL-IRa peaked at 9 h (34.5 ± 13.4 ng/joint). The amount of IL-IRa was 180–200-fold molar excess of IL-1, and a large amount of IL-IRa was sustained for I week. Both IL-1β and IL-IRa were mainly produced by synovial exudate cells. Arthritis was reproduced by rabbit IL-1β. LPS-induced leucocyte infiltration was inhibited 70–75% by rabbit IL-IRa. Loss of PG in LPS-arthritis was prevented by IL-1Ra and also by neutrophil elastase inhibitor, and superoxide dismutase. In leucopenic rabbits, injection of LPS induced neither production of IL-1β nor loss of PG. Direct injection of inflammatory exudated cells in leucopenic rabbits reproduced loss of PG. and there was only a partial recovery by IL-1Ra. These results suggest that LPS-initiated IL-1 acts as a key mediator in LPS-arthritis and that endogenous IL-1 Ra may suppress a part of IL-1 activity at the site, but its amount was too low for suppression of the produced IL-1. Loss of PG is a sequela of infiltrated leucocytes and leucocyte-derived elastase, and superoxide anion may play a pivotal role in the destruction of cartilage.
IL-2 enhances polyclonal IgM but not IgM-rheumatoid factor synthesis by activated human peripheral blood B cells
Authors: CALLAGHAN M , WHELAN A , FEIGHERY C , BRESNIHAN B
Published: August 2010

IgM-rheumatoid factor (RF) is thought to be involved in the pathogenesis of rheumatoid arthritis (RA). Several cytokines are known to regulate immunoglobulin synthesis. In this study the effects of IL-2 on polyclonal IgM and IgM RF synthesis were compared. Cytokines were added to peripheral blood B cells from normal subjects and patients with RA after activation by Staphylococcus aureus Cowan 1 (SAC). The addition of IL-2. but not IL-4 or IL-6, resulted in significant enhancement of IgM synthesis in cultures from both healthy subjects and patients with RA. Similar degrees of enhancement were seen in both peripheral blood mononuclcar cell and highly purified B cell cultures. IgM-RF was synthesized after activation in cultures from healthy subjects and spontaneously in cultures from RA patients. In contrast to polyclonal IgM synthesis, IL-2 failed to augment IgM-RF synthesis in cell cultures from either healthy subjects or RA patients. This study demonstrates different effects of IL-2 on IgM and IgM-RF synthesis.
Clustering of neutrophil leucocytes in serum: possible role of Clq-containing immune complexes
Authors: STURFELT G , JONSSON H , HELLMER G , SJöHOLM A G
Published: August 2010

Clustering activity for neutrophil granulocytes was generated in pooled normal human serum (NHS) by incubation of the serum with preformed IgG aggregates, but not in heat-treated NHS (56°C, 30 min), indicating that the function was complement-dependent. Judging from results of experiments with complement-deficient sera, and serum depleted of Clq, factor D and properdin, recruitment of the complement system beyond Cl was not required for induction of the activity. Zymosan treatment of NHS resulted in some neutrophil clustering activity, but recombinant C5a had a limited effect. Clq added to heat-treated NHS in conjunction with preformed IgG aggregates supported neutrophil clustering in a dose-dependent manner. The serum Clq inhibitor, a chondroitin 4-sulphate proteoglycan known to interact with the collagenous part of Clq, clearly reduced neutrophil clustering in heat-treated NHS supplemented with Clq and IgG aggregates. The Clq inhibitor also reduced the inherent neutrophil clustering activity of some sera from patients with systemic lupus erythematosus (SLE). Neutrophil clustering activity in SLE serum was earlier shown to be inversely related to the number of circulating neutrophils in vivo. Although the precise mechanisms remain unclear, we propose that Clq-containing immunoglobulin complexes mediate neutrophil clustering through Clq receptors, and that this might contribute to pathogenesis of immune complex diseases such as SLE.
Trichosanthin, an initiator of the alternative complement activation pathway
Authors: CHEN X , MA B-L
Published: August 2010

Trichosanthin (TCS), a protein purified from the plant Trichosanthes Kirilowii Maxim, activates normal human serum complement via the alternative pathway, as shown by TCS-induced C3 conversion in normal serum and its prevention by depletion of factor B, but not with the addition of EGTA. Injection of TCS to BALB/c mice consumed the complement alternative pathway (APC) activity in serum, implying in vivo activation of the alternative pathway by TCS. Elevation of peripheral blood leucocyte count as well as protein exudation and neutrophil accumulation in the peritoneal cavities could be induced by peritoneal injection of TCS. The main effect of complement activation by TCS was demonstrated to be induction of neutrophil accumulation.
Antibodies to the protein core of the small cell lung cancer workshop antigen cluster-w4 and to the leucocyte workshop antigen CD24 recognize the same short protein sequence leucine-alanine-proline
Authors: WEBER E , LEHMANN H P , BECK-SICKINGER A G , WAWRZYNCZAK E J , WAIBEL R , FOLKERS G , STAHEL R A
Published: August 2010

We recently described the identity of the small cell lung cancer (SCLC) cluster-w4 antigen and the human B cell differentiation marker CD24, a glycosylphosphatidylinositol (GPI)-anchored, highly glycosylated surface molecule of only 31–35 amino acids [15]. The specificities of three anti-cluster-w4 and of eleven anti-CD24 MoAbs have been investigated with respect to their binding capacity to the protein core of cluster-w4/CD24 antigen. Four overlapping peptides spanning this protein core were synthesized. MoAbs shown to bind to two overlapping peptides by antibody binding inhibition using the clustcr-w4/CD24-positive SCLC cell line SW2 and by direct peptide binding detected in an ELISA were investigated in more detail. To determine the exact epitopes recognized by these MoAbs, an epitope mapping assay using peptides synthesized onto polyethylene pins was established. The three anti-cluster-w4 MoAbs SWA11, SWA21 and SWA22 and the anli-CD24 MoAbs OKB2 and ALB9 recognized the same short leucine-alanine-proline (LAP) sequence in an area without potential glycosylation sites close to the GPI anchor of the protein core of the cluster-w4/CD24 antigen.
Characterization of an HLA-DR4-restricted T cell clone recognizing a protein moiety of small nuclear ribonucleoproteins (UsnRNP)
Authors: WOLFF-VORBECK G , HACKL W , FENNING S , KRAWINKEL U , LÜHRMANN R , PETER H H , SCHLESIER M
Published: August 2010

In sera of patients with mixed connective tissue disease(MCTD, Sharp Syndrome) high titres of IgG autoantibodies to UlsnRNP-specific proteins are found. The isolated occurrence of these autoantibodies is highly associated with the HLA-DR4 haplotype. snRNP-specific T cells are supposed to be involved in this autoantibody production. To address this question we cultured mononuelear cells from MCTD patients and healthy donors with a highly purified UsnRNP preparation from HeLa cells using bulk or limiting dilution cultures. Secondary responses to snRNP were detected only rarely with T cell lines from two patients and two controls, and turned out to be unstable during further expansion. One T cell line derived from a healthy individual retained its snRNP reactivity upon limiting dilution cloning and could be characterized in detail. The CD4+ T cell clone recognized native snRNP particles presented by monocytes in an HLA-DR4 (Bl*0401)-restricted manner. Separation of the protein and RNA moieties of snRNP particles revealed that the T cell clone responded specifically to the protein fraction, but not to RNA and diverse control antigens. Sequencing of the T cell receptor α and β chain cDNAs revealed that the clone used the Val4.2 and Vβ14 elements. Upon antigen-specific and mitogenic stimulation the T cell clone showed a ThI-specific cytokine pattern, and did not provide helper activity for in vitro immunoglobulin production. This study demonstrates the presence of self-reactive snRNP-specific T cells in a healthy donor. The T cell clone may not represent a helper T cell for the formation of UlsnRNP-specific autoantibodies.
Anti-5S RNA/protein (RNP) antibody levels correlate with disease activity in a patient with systemic lupus erythematosus (SLE) nephritis
Authors: GUIALIS A , PATRINOU-GEORGOULA M , TSIFETAKI N , AIDINIS V , SEKERIS C E , MOLITSOPOUIOS H M
Published: August 2010

A patienl with systemic lupus erythematiosus (SLE) and nephritis without antibodies to dsDNA but with antibodies lo a 5S RNA/protcin (RNP) complex is presented. Combined RNA precipitation and Western blotting experiments strongly suggested that these newly Identified autoantibodics recognized a distinct epitope on the 1.5 ribosomal protein of the L5/5S RNP complex first described by steitz et al. [1]. Quantification of the anti-5S RNI* antibody levels was done by hybridizing Northern blots of immunoprecititated RNA from serial serum samples with a 32p-labelled oligoprobc specific for the 5S ribosomal RNA. These studies revealed a strong association between unti-5S RNP autoanlibody litre and severity of SLE nephritis over a 3-ycar prospective study. Our results indicate that the L5/5S RNP can be a target of autoimmune response, and may serve, in some cases, as marker of SLE severity and response to therapy.
Adhesion of peripheral blood lymphocytes of children with arthritis to human umbilical vein endothelial cells
Authors: OEN K , DANELL G , STEWART S , WILKINS J , TAZUMl K , JACOBSON K
Published: August 2010

To determine whether adhesion of peripheral blood lymphocytes (PBL) of patients with juvenile rheumatoid arthritis (JRA) may be enhanced, adhesion of PBL of children with JRA. children with seronegative spondyloarthropathies (SSA). age-appropriate and adult controls, to human umbilical vein endothelial cells (HUVEC) was assessed in vitro. B and CD4 T lymphocytes in initial, adherent, and non-adherent cell fractions were identified by flow cytometry. B lymphocytes of all the younger subjects combined had a higher adherence to activated HUVEC compared with B lymphocytes of the adult donors. Except for greater adherence of HLA-DR+ CD4 T cells, lymphocytes of children with JRA showed no enhanced adhesion to either unactivated or activated HUVEC. The percentage of B cells adherent to activated HUVEC in each of the subject groups was 1-5 3-6-fold higher than adherent CD4 T lymphocytes. Surface analyses indicated higher percentages of CD49d (α4)+ and CD29 (β1)+ CD4 T lymphocytes in adherent cells, but less of a differential in CD49 (α4)+ and no difterence in CD29(βl)+ B lymphocytes. There were fewer Leu-8(L-selectin)+ B and Leu-8+ CD4T cells among adherent cells. The data suggest a greater adhesive capacity of B lymphocytes compared with CD4 T lymphocytes which is unrelated to disease, and the possibility that B lymphocytes may utilize adhesion molecules distinct from those of CD4 T lymphocytes. Only a small subset of T cells of patients with JRA may have an enhanced capacity for adhesion to endothelium.
High-density proteoglycan induces specific suppression of adjuvant-induced arthritis in rats
Authors: SAIKAWA I , HOTOKEBUCHI T , MIYAHARA H , TOKITO T , MAEDA T , ARITA C , SUGIOKA Y
Published: August 2010

In vitro data support the view that T cells in adjuvant-induced arthritis (AIA) respond to the proteoglycan (PG) component of articular cartilage; however, an in vivo role for PG in AIA has yet to be shown. To do so. we examined the effects of pretreatment with bovine cartilage high density PG (HDPG) on AIA induced by heat-killed Mycobacterium butyricum in Lewis rats. Purified bovine cartilage HDPG emulsified in Freund's incomplete adjuvant (FIA) was injected intradermally into rats 7 days before challenge with Myco. butyricum. The severity of arthritis was significantly suppressed in rats pretreated with as little as 0·75 mg of HDPG, and the arthritis was completely suppressed in rats pretreated with 3·0 mg of HDPG. This suppression was specific, as the same treatment did not protect against type II collagen-induced arthritis. Suppression of AIA is primarily a property of the HDPG, as suppression of the arthritis was significantly less with pretreatment with 3.0 mg of middle density fractions of PG, and no suppression was observed with pretreatment with the lowest density fraction of PG. Thus we report that pretreatment with cartilage HDPG, but not lower density PG, can induce specific suppression of AIA. These in vivo results support the view that immunity to cartilage HDPG plays a major role in the pathogenesis of AIA, and can induce specific tolerance to this type of arthritis.
Abnormalities in subset distribution, activation, and differentiation of T ceils isolated from large intestine biopsies in HIV infection
Authors:   THE BERLIN DIARRHOEA/WASTING SYNDROME STUDY GROUP, SCHNEIDER T , ULLRICH R , BERGS C , SCHMIDT W , RIECKEN E O , ZEITZ M
Published: August 2010

Intestinal T cells have a unique stale of activation and differentiation which might specifically affect or be affected by HIV infection. Lymphocyte subsets in the peripheral blood are well characterized., but our knowledge about intestinal lymphocytes in HIV infection is incomplete. We therefore analysed lymphocytes isolated from large intestine biopsies of AIDS patients and controls by threecolour cytofluorometry. In the large intestine of HIV-infected patients CD4 T cells were reduced and CD8 T cells were increased compared with controls. Most of the CD8 T cells in the colorectal mucosa of AIDS patients were of the cytotoxie phenotype. Activated and resting CD4T cells were similarly reduced, the expression of CD25 and HLA-DR of CD8 T cells was unaltered and increased. respectively. In intestinal CD4 T cells the expression of CD29 was decreased, but the expression of CD45RO and HML-1 was normal. CD8 T cells had a decreased expression of all these differentiation markers. Our findings demonstrate substantial alterations in subset distribution, activation, and differentiation of large intestine T cells, which may contribute to the secondary infections and malignancies commonly observed in the gut of AIDS patients.
Serial functional affinity of autoantibodies in anti-glomerular basement membrane disease
Authors: MARRIOTT J B , OLIVEIRA D B G
Published: August 2010

Anti-glomertilar basement membrane (GBM) disease is caused by an autoantibody directed against an epilope on ihc α3 chain of type IV cullagen. Animal models demonstrate that the higher the affinity of such antibodies, the greater the degree of glomerular injury. Affinity maturation (the process whereby somatic mutation followed by antigen selection leads to an increase in affinity of antibody) might therefore be of pathogenic significance if it occurs in human anti-GBM disease. We have examined serial samples from nine patients with anti-GBM disciisc and looked for evidence of changing functional affinity by measuring the inhibition of binding produced by the mild chaotrope diethylamine (DEA) in an anti-GBM antibody ELISA. Seven patients showed no change in the inhibition produced by DEA with time. Two patients showed an apparent decrease with time in the inhibition produced by DEA; this apparent increase in functional affinity proved, on further investigation, to represent simply ihe loss of anti-GBM antibodies. These results may imply that affinity maturation has been completed by the time that patients present wiih anti-GBM disease. If there had been evidence for a further increase in functional affinity after this point then this might have added extra urgency to the need for removal of these autoantibodies as part of treatment.
Increased cyclosporine sensitivity of T cells from cord blood compared with those from the adult
Authors: MCDOUALL R M , SUITTERS A J , SMITH H , YACOUB M H , ROSE M L
Published: August 2010

Despite the increasing numbers of paediatric transplants performed, little is knowtn about the immuine responses of T lymphocytes in human neonates. Here we have compared the effects of cyclosporinc on the phytohacmagglutinin (PHA) response of immature (cord) and mature (adult) lymphocytes using the following parameters of activation: (i) proliferation, measured by ‘H-thymidine uptake: (ii) expression of cell surface IL-2 receptor; (iii) release of IL-2 into the supernatant. Cyclosporine was added to cultures of PHA-stimulated lymphocytes at doses ranging from 5 to 5000 ng/ml. The proliferative response of cord lymphocytes was considerably more sensitive to cyclosporine at each dose, so that 50% inhibition was achieved by 6 ng/ml and 21·5 ng/ml doses of cyclosporine on cord and adult lymphocytes, respectively, Expression of the IL-2 receptor by PHA-activated T cells and their subsets was assessed by flow cytometry. Cyclosporine inhibited IL-2 receptor expression to a significantly greater degree in cord CD4 and CD8 cells (49·7% and 70·1%) than in adults (17·9% and 30·0%). Biologically active IL-2 release was measured using the IL-2-dependent cell line CTLL-2. Cyclosporine at doses 50–5000 ng/ml produced 80–99% inhibition of both cord and adult responses. However, at very low doses (5 ng/ml) cyclosporine produced 69·3%, inhibition of cord lymphocytes, compared with 42·0% of adult lymphocytes. These results suggest that the T cells of neonates are considerably more sensitive to cyclosporine than are adult T cells.
Mucosal tolerance and suppression of collagen-induced arthritis (CIA) induced by nasal inhalation of synthetic peptide 184-198 of bovine type II collagen (CII) expressing a dominant T cell epitope
Authors: Staines N A , Harper N , Ward F J , Malmström V , Holmdahl R , Bansal S
Published: August 2010

The purpose of the study was to map the dominant T cell epitope of the CB11 sequence of CII in RT1u haplotype rats and to determine if, when used as a synthetic peptide, it would induce tolerance to protect against CIA. A dominant epitope corresponding to residues 184–198 included in the sequence of the CB11 fragment of bovine CII was identified in proliferation assay using peptides in an epitope scanning system using synthetic peptides of 15 amino acids, overlapping by 12 amino acids. This epitope is bovine-specific, but cross-reacts with the corresponding rat peptide. Minor epitopes in the bovine CB11 sequence were also autoantigenic. Use of independently synthesized and purified 184–198 peptide confirmed its dominance in the T cell responses of arthritic rats. The peptide itself was not arthritogenic. Cells from lymph nodes draining arthritic feet were particularly responsive to the dominant peptide sequence, and showed evidence of epitope spreading to include reactions to at least four subdominant epitopes. Mucosal tolerance was successfully induced by instilling CII into the nose of rats before induction of CIA; this was found to delay the onset of disease, reduce mean disease severity, shift the anti-CII antibody response to favour antibodies of the IgGl, rather than the IgG2b isiotype, and to reduce T cell reactivity to both CII and to the 184–198 peptide. The dominant 184–198 peptide itself had the same tolerogenic effects when given nasally to rats daily, on the 4 days immediately preceding the induction of CIA. Two forms of CIA with acute and delayed disease onset were each modified by pre-treatment with the peptide. This study demonstrates that mucosal tolerance to CII can be induced by delivering it nasally in a way similar to that achieved previously by oral delivery, and that the use of an immunodominant epitope contained in a synthetic peptide will also suppress the immunologic and arthritic responses to collagen.
Azurocidin is a novel antigen for anti-neutrophil cytoplasmic autoantibodies (ANCA) in systemic vasculitis
Authors: Zhao M H , Lockwood C M
Published: August 2010

We isolated a 27-kD protein using cation exchange chromatography from an acid extract of neutrophil granules. N-terminal amino acid sequence analysis of the first 10 residues showed that this protein is azurocidin, a member of the family of neutral serine proteinase found in the neutrophil, which shares amino acid sequence homology with the three other neutral serine proteinases, elastase, proteinase 3 (PR3) and cathepsin G, but unlike them is without proteolytic activity. To test whether, in addition to these proteases, azurocidin might be a target for the humoral autoimmune responses associated with human vasculitis, 185 indirect immunofluorescence (IIF)-positive ANCA sera, made up of four groups of sera with specificities for PR3 (n= 37), myeloperoxidase (MPO; n= 50), bactericidal/permeability-increasing protein (BPI; n= 41) and sera that recognized none of them (triple negative, n= 57), and 46 normal sera were screened for IgG anti-azurocidin antibodies using an ELISA incorporating purified azurocidin. Twenty of the 185 IIF-positive sera and 2/46 normal sera displayed reactivity with azurocidin. Positive sera could blot the 27-kD band by Western blot analysis. Further study of the 20 positive sera revealed that: (i) 10 also had autoreactivity for MPO, of which six additionally recognized lactoferrin; (ii) two had reactivity with BPI; (iii) the remaining eight sera were positive only for azurocidin. All 20 sera were from patients with systemic vasculitis, and four of the six sera with triple reactivity (for azurocidin, MPO and lactoferrin) were from patients with hydralazine-induced vasculitis. We concluded that: (i) azurocidin is a novel ANCA antigen; (ii) anti-azurocidin antibodies from a subgroup of patients might represent the consequence of a drug-induced multi-clone activation.
Detection of hepatitis C virus (HCV) proteins by immunofluorescence and HCV RNA genomic sequences by non-isotopicin situhybridization in bone marrow and peripheral blood mononuclear cells of chronically HCV-infected patients
Authors: Sansonno D , Iacobelli A R , Cornacchiulo V , Iodice G , Dammacco F
Published: August 2010

Immunofluorescence (IF) to detect HCV antigens and non-isotopic in situ hybridization (NISH) to detect HCV RNA genome were carried out on bone marrow (BM) and peripheral blood (PB) mononuclear cells (MC) of 11 chronically HCV-infected patients. In four patients (36.4%) HCV antigens were detected in monocytes macrophages as well as in B lymphocytes in both BMMC and PBMC. Positive T lymphocytes in BMMC were found in three of them, but only one patient showed positive T cells in PBMC. NISH invariably demonstrated minus and plus HCV RNA genomic strands either in monocytes macrophages or B and T lymphocytes in BMMC and PBMC in the four HCV antigen-positive patients and in two further patients not expressing viral proteins in blood MC. IF signals appeared diffusely distributed within the cytoplasm, or as brilliant granules in distinct submembrane areas or else in cytoplasm membrane. Nuclei never stained. Similarly, NISH displayed HCV RNA accumulation restricted to MC cytoplasm only, nuclei being persistently negative. NISH, however, was unable to detect cell membrane signal. Infection of blood MC is a common event in naturally acquired HCV infection, since none of these patients was conditioned by immunomodulating or immunosuppressive therapies. No difference was found in terms of mean age, length of disease, anti-HCV immune response, type and severity of chronic liver damage between patients with HCV-infected MC and patients without cell infection. These results demonstrate that HCV can infect BMMC and PBMC that represent important extrahepatic sites of virus replication, and may help to explain the immunological abnormalities observed in chronic HCV carriers.
Selected Th1 and Th2 cytokine mRNA expression by CD4+ T cells isolated from inflamed human gingival tissues
Authors: Fujihashi K , Yamamoto M , Hiroi T , Bamberg T V , McGhee J R , Kiyono H
Published: August 2010

Elevated numbers of plasma cells are associated with localized and chronically inflamed gingiva of patients with adult periodontitis. However, only limited information is currently available as to how cytokines produced by CD4+ T cells are involved in these increased B cell responses in affected gingival tissues. When gingival mononuclear cells (GMC) were isolated from inflamed tissues and examined by flow cytometry, ∼20–30% of lymphocytes were CD4+ T cells. For the analysis of Th1 and Th2 cytokine expression by these CD4+ T cells, RNA was extracted and reverse transcriptase-polymerase chain reaction (RT-PCR) was performed by using specific 5' and 3' primers for interferon-gamma (IFN-γ) and IL-2 (Th1), IL-4, IL-5, IL-6, IL-10 and IL-13 (Th2) and β-actin (internal control). Two distinct cytokine profiles were noted based on the expression of selected Th1 and Th2 cytokines, where one pattern was represented by expression of mRNA for IFN-γ, IL-6, IL-10 and IL-13, while the second consisted of mRNA for IFN-γ, IL-6 and IL-13. In most samples, mRNA for IL-2, IL-4 and IL-5 were not detected by cytokine-specific RT-PCR. When RNA was isolated from CD4+ T cells of concanavalin A-stimulated peripheral blood mononuclear celts (PBMC) of the same patients and examined by RT-PCR. mRNA for all Th1 and Th2 cytokines were detected. These findings suggest that although human CD4+ T cells are capable of producing an array of Th1- and Th2-type cytokines, the CD4+ T cells associated with periodontitis are limited to production of IFN-γ, IL-6, IL-13 and in some instances IL-10. CD4+ T cells from diseased periodontal tissues are divisible into two groups based upon whether or not IL-10 is produced, together with IFN-γ, IL-6 and IL-13.
A prognostic role for anti-phosphatidyl choline antibodies in human cerebral malaria
Authors: Das B K , Parida S , Ravindran B
Published: August 2010

Anti-phosphatidyl choline antibodies (αPC) have been measured in adult patients from Orissa, India with Plasmodium falciparum infection of varying clinical severity. Significantly raised levels of αPC were observed in infected individuals in comparison with controls. The IgG αPC were found to be generally more than IgM αPC in most cases. The IgG αPC levels were significantly more in those cases of cerebral malaria who recovered fully after quinine administration in comparison with fatal cases not responding to quinine therapy, indicating a role for αPC in prognosis of adult cerebral malaria. There was no significant difference in levels of αPC IgG between non-cerebral and fatal cerebral malaria patients, indicating an absence of a direct protective role in the development of cerebral manifestations. Subgroup typing of IgG with αPC activity indicated IgG3 to be the predominant type, followed by IgG2. IgG1 and IgG4. A significant inverse relationship between serum tumour necrosis factor-alpha (TNF-α) levels and IgG1 antibodies with αPC activity was found, emphasizing the importance of αPC in modifying disease severity. These observations appear to give credence to recent reports in the literature indicating that toxic malarial antigens consist of phospholipids and that antibodies to phospholipids (αPL) inhibit such antigens in experimental systems.
Aggravation of experimental allergic encephalomyelitis (EAE) by administration of nitric oxide (NO) synthase inhibitors
Authors: Ruuls S R , van der Linden S , Sontrop K , Huitinga I , Dijkstra C D
Published: August 2010

Macrophages constitute a large proportion of the inflammatory cells that infiltrate the central nervous system (CNS) of animals with EAE. Through the production of inflammatory mediators these infiltrating macrophages can contribute to the regulation of the immune reaction within the CNS, that eventually results in neurological deficits associated with EAE. NO, a free radical produced by macrophages and other cell types, has been put forward as such an immune mediator. In the present study we show that macrophages isolated from the CNS of Lewis rats with clinical signs of EAE produce elevated amounts of NO. We treated rats, in which EAE was induced, with Nw-nitro-L-arginine-methylester or NG-monomethyl-L-arginine, inhibitors of NO synthase, either systemically via intraperitoneal injection, or intracerebrally via a cannula placed in the lateral ventricle. Both treatments resulted in a marked aggravation of clinical signs of EAE. These data point to an important role of NO, produced by infiltrating macrophages, as an immune-suppressor in the disease process during EAE.
Production of IL-6 by T cells from the femoral head of patients with rapidly destructive coxopathy (RDC)
Authors: Tamai M , Sagawa K , Kawabata R , Inoue A , Itoh K
Published: August 2010

RDC is a syndrome with unknown etiology that causes rapid destruction of a hip joint. We have investigated the production of osteoclast-activating cytokines (IL-6, IL-1α and tumour necrosis factor-alpha (TNF-α)), interferon-gamma (IFN-γ) and IL-8 by T cells in the affected joint. The level of IL-6 produced by the T cell lines (TCL) established from the femoral head was significantly higher than that from patients' or healthy donors' peripheral blood mononuclear cells (PBMC). IL-6 production by the TCL from synovial membrane or from patients' PBMC was also significantly higher than that from healthy donors' PBMC. IL-1α production by the TCL from the femoral head was significantly higher than any of the other groups when all the TCL were used for the analysis. TNF-α production was highest in the TCL from patients' PBMC. The levels of IFN-γ or IL-8 were not significantly different among these four groups. The plasma levels of all these cytokines except for IFN-γ, that was rather lower, in RDC patients were not significantly different from those in osteoarthrosis or trauma patients, or healthy donors. These results suggest that T cells at the affected femoral head, and also synovial membrane to some extent, are involved in bone resorption through the production of IL-6 and probably IL-1α in patients with RDC.
A double blind, placebo-controlled, crossover therapy study with natural human IL-2 (nhuIL-2) in combination with regular intravenous gammaglobulin (IVIG) infusions in 10 patients with common variable immunodeficiency (CVID)
Authors: RUMP J A , JAHREIS A , SCHLESIER M , STECHER S , PETER H H
Published: August 2010

Ten CVID patients with defective IL-2 synthesis in vitro were treated with nhuIL-2 in a placebo-controlled, double blind, crossover therapy study during a period of 12 months. No severe side-effects of nhuIL-2 were recorded. Marginal serum nhuIL-2 levels were measurable in individual patients only during the therapy phase. Serum levels of soluble IL-2 receptors were unaffected by the therapy. nhuIL-2 and placebo groups did not differ significantly with respect to requirement of IVIG substitutions which were performed whenever serum IgG levels dropped below 5 g/l: a total of 53 IVIG infusions (corresponding to 17.6 g IgG/month per patient) was necessary during the placebo phase, and 48 infusions (16-4 g IgG/month per patient) during the nhuIL-2 treatment phase. Thus, nhuIL-2 therapy was ineffective in improving spontaneous IgG synthesis in vivo. Nevertheless, the group of patients receiving nhuIL-2 during the first 6 months of the study exhibited a significant reduction of severe infections (n= 25) during the following 6 months of placebo treatment (n = 7) (P< 0–045). The infection score dropped in this group from 181 to 23 (P < 0015). Patients of the second group receiving first placebo and then nhuIL-2 did not experience a significant difference in number and score of infectious episodes: 25 infections were recorded during the first 6 months and 24 during the following 6 months. We suppose that nhuIL-2 therapy of CVID patients reduces susceptibility to severe infections, possibly via the induction of a specific antibody response, which is effective at the earliest 6 months after initiating nhuIL-2 therapy.
Isotypic analysis of maternally transmitted Plasmodium falciparum-specific antibodies in Cameroon, and relationship with risk of P. falciparum infection
Authors: DELORON P , DUBOIS B , LE HESRAN J Y , RICHE D , FIEVET N , CORNET M , RINGWALD P , COT M
Published: August 2010

In malaria-endemic areas, infants are relatively protected against malaria infection. Such protection is though to be related principally to the transplacental transfer of maternal antibodies. We measured total and Plasmodium falciparum-specific IgG (including subclasses), IgM, and IgE antibodies in 154 paired maternal-cord serum samples from an area of meso- to hyperendemic malaria in South Cameroon. Among peripheral mother blood samples, total IgG and IgM were detected in all samples, IgE in all but two. Plasmodium falciparum-specific IgG were detected in all serum samples, IgM and IgE in < 75% of samples. The prevalence rates of anti-P. falciparum IgG subclasses varied from 75% to 97%. With the exception of P. falciparum-sptcifxc IgG, all antibody class and subclass levels were lower in cord blood than in peripheral mother blood. Plasmodium falciparum-spccific IgGl and IgG3 isotypes were transferred to the offspring more often and more efficiently than IgG2 and IgG4. The detection of total and P. falciparum-specific IgM and IgE in some cord serum samples demonstrated that fetuses can mount humoral response against malaria parasites. We also determined whether transplacentally acquired antibodies protect against malaria infection by relating the antibody levels at birth to the risk of acquiring P. falciparum infection during the first 6 months of life. Among various classes and subclasses of P. falciparum-spccific antibodies, only IgG2 were related to a decrease in the risk of acquiring a P. falciparum peripheral blood infection from birth to 6 months of age.
Specificities of anti-neutrophil autoantibodies in patients with rheumatoid arthritis (RA)
Authors: BRIMNES J , HALBERG P , JACOBSEN S , WIIK A , HEEGAARD N H H
Published: August 2010

The objective of this study was to characterize antigens recognized by neutrophil-specific autoantibodies from patients with RA. Sera from 62 RA patients were screened by indirect immunofluorescence (IIF). Positive sera were further tested by ELISAs for antibodies against various granule proteins and by immunoblotting of electrophoretically separated cell, granule or nuclear extracts. Forty-two sera (68%) reacted with ethanol-fixed neutrophils. In the ELISAs 32% of the 28 medium to strongly IIF-positive sera were negative, while 43% were weakly positive for more than one antigen. Immunoblots of whole neutrophils showed IgG reactions at 25–35 kD, in the 55-kD region, at 80 kD, and at 110kD. Most sera reacted with more than one band. Except for the 55-kD antigen, none of the antigens appeared in lymphocytes. The most notable reactivity in subcellular fractions was with lactoferrin and with bands of 25–35 kD from nuclei. In conclusion, anti-neutrophil autoantibodies from RA patients recognize different antigens in the cytoplasm and in the nucleus. Lactoferrin is one of the common antigens recognized, but also unknown nuclear antigens of 25–35 kD mol. wt are involved.
Alteration of DNA methylation levels in MRL lupus mice
Authors: MIZUGAKI M , YAMAGUCHI T , ISHIWATA S , SHINDO H , HISHINUMA T , NOZAKI S , NOSE M
Published: August 2010

Recent reports suggest that DNA methylation is involved in the cause of autoimmune disease. We investigated the alteration of DNA methylation levels in lupus strains of mice, MRL/lpr as a model, which develop an age-dependent lymphadenopathy and autoimmune disease. DNA methylation levels of thymus and axillary lymph nodes in 20-week-old MRL/lpr mice, which are in an autoimmune disease state, were lower than those of 4-week-old MRL/lpr mice with no symptoms as yet. No significant changes were observed in MRL/4- strain mice, which seemed normal at least 20 weeks, while DNA methylation levels in the spleen of both strains of mice increased significantly from the age of 4 to 20 weeks. However, no significant changes of DNA methylation levels in peripheral blood were observed with ageing in MRL strains. Moreover, we clarified that administration of 5-azacytidine had a strong effect on longer survival of MRL/lpr mice and reduced DNA methylation levels in the axillary lymph nodes and spleen. The possible relevance of DNA methylation levels to the progression of autoimmune disease is discussed.
Studies of epitope restriction on myeloperoxidase (MPO), an important antigen in systemic vasculitis
Authors: SHORT A K , LOCKWOOD C M
Published: August 2010

Anti-neutrophil cytoplasmic antibodies are important components of the inflammatory response in patients with systemic vasculitis. Their role in the pathogenesis of these conditions remains incompletely defined. Several antigens have been identified, and MPO is one of the most important. To gain more understanding of the immune mechanisms involved, we were keen to see if the antibody response to MPO was restricted, or whether there was a general loss of tolerance to the whole surface of the molecule. To study the epitopes we employed both ELISA and biosensor technology, and were able to demonstrate restriction both in the number and localization of the epitopes being recognized.
Antigen-presenting properties of gingival fibroblasts in chronic adult periodontitis
Authors: WASSENAAR A , SNIJDERS A , ABRAHAM-INPIJN L , KAPSENBERG M L , KIEVITS F
Published: August 2010

Chronic periodontitis is characterized by dense infiltrations of T lymphocytes in the connective tissue, which consists mainly of gingival fibroblasts. It is becoming increasingly clear that T lymphocytes and gingival fibroblasts are capable of influencing each other. For example, the T cell cytokine interferon-gamma (IFN-γ) is able to induce MHC class II molecules on the surface of several cell types, including gingival fibroblasts. Histological sections of chronically inflamed gingival tissue showed a great number of CD4+ and CD8+ T cells that produced IFN-γ, and in addition showed abundant expression of MHC class II molecules on gingival fibroblasts. Therefore, we investigated whether these gingival fibroblasts acquire the capacity to carry out MHC class II-restricted functions such as antigen presentation to local T cells. In this study, we show that IFN-γ-treated gingival fibroblasts were able to function as antigen-presenting cells (APC) for superantigen-mediated T cell proliferation. However, these fibroblasts failed to present whole-cell antigens of periodontitis-associated bacteria. Moreover, gingival fibroblasts inhibited the presentation of the whole-cell antigens of these bacteria by professional APC. This inhibition could be overcome by the addition of IL-2. These results suggest that gingival fibroblasts play an important role in the local specific immune response in chronic inflammatory periodontal lesions by regulating the response of infiltrating T cells.
Anti-heat shock protein (hsp)72 antibodies are present in patients with Graves' disease (GD) and in smoking control subjects
Authors: PRUMMEL M F , VAN PAREREN Y , BARKER O , WIERSINGA W M
Published: August 2010

Hsp72 is expressed in thyroidal tissue and on retroocular fibroblasts from patients with GD. In this study we investigated whether GD patients have hsp72 antibodies, and if they correlate with disease characteristics. Because smoking is associated with GD and might up-regulate hsp72 expression, we also studied the effect of smoking on hsp antibody levels. Hsp72 IgG antibodies were determined by dot-blotting, using recombinant human stress-inducible hsp72. Dot-blot densities were measured using a videoimaging system in 38 healthy controls, 45 patients with GD, including 34 with varying degrees of ophthalmopathy, and in 13 GD patients before and after treatment of thyrotoxicosis with methimazole. Hsp72 antibodies were detectable more frequently in GD patients (26/45, 58%), than in controls (12/38, 32% P<0·02). GD patients had higher antibody levels than controls; mean ± s.e.m. optical densities: 26·8 ± 2·6 versus 18·8 ± 2·4 (P = 0·018). Levels did not correlate with any parameter of disease severity or activity. Hsp72 antibody levels did not change upon reaching euthiyroidism. In controls, but not in patients, hsp72 antibodies could be detected more frequently in smokers (6/10, 60%) versus non-smokers (6/28, 21%; P = 0·024). Patients with GD have higher hsp72 IgG antibody levels than controls, without correlation with any disease characteristic. Among healthy controls, smoking is associated with elevated hsp72 antibodies. This suggests that these antibodies might be a marker for autoimmune susceptibility.
Quantification of Bax/Bcl-2 ratios in peripheral blood lymphocytes, monocytes and granulocytes and their relation to susceptibility to anti-Fas (anti-CD95)-induced apoptosis
Authors: VAN DER VLIET H J J , WEVER P C , VAN DIEPEN F N J , YONG S-L , TEN BERGE I J M
Published: August 2010

Neutrophils have the shortest half-life among circulating leucocytes and rapidly undergo apoptosis in vitro. The homologous Bcl-2 and Bax proteins have opposing effects, with Bcl-2 extending cellular survival and Bax promoting cell death following an apoptotic stimulus. We determined Bcl-2 to Bax expression ratios in peripheral blood lymphocytes, monocytes and granulocytes and related them to the susceptibility of these cells to anti-Fas (anti-CD95)-induced apoptosis. Here, we show that Bax/Bcl-2 ratios are high in granulocytes and relatively low in monocytes and lymphocytes. Furthermore, we show a relation between this ratio in the different leucocyte subsets and their susceptibility to anti-Fas-induced apoptosis, with granulocytes showing the highest susceptibility, followed by monocytes and lymphocytes. It is concluded that the balance between Bcl-2 and Bax forms an apoptotic rheostat, which seems to determine sensitivity to apoptosis.
Translational Mini-Review Series on Toll-like Receptors: Networks regulated by Toll-like receptors mediate innate and adaptive immunity
Authors: Parker L C , Prince L R , Sabroe I
Published: August 2010

The Toll-like receptor (TLR) family provide key components of mammalian immunity and are part of the earliest surveillance mechanisms responding to infection. Their activation triggers the innate immune response, and is crucial to the successful induction of Th1/Th2-phenotyped adaptive immunity. Innate immunity was long considered to be non-specific and somewhat simple compared to adaptive immunity, mediated via the engulfment and lysis of microbial pathogens by phagocytic cells such as macrophages and neutrophils, and involving no complex protein–protein interactions. The emergence of the TLR field has contributed to a revision of our understanding, and innate immunity is now viewed as a highly complex process, in line with adaptive immunity. This review will give a brief overview of our current knowledge of TLR biology, and will focus on TLRs as key components in complex networks that activate, integrate and select the appropriate innate and adaptive immune responses in the face of immunological danger.
Translational Mini-Review Series on Type 1 Diabetes: Systematic analysis of T cell epitopes in autoimmune diabetes
Authors: Di Lorenzo T P , Peakman M , Roep B O
Published: August 2010

T cell epitopes represent the molecular code words through which the adaptive immune system communicates. In the context of a T cell-mediated autoimmune disease such as type 1 diabetes, CD4 and CD8 T cell recognition of islet autoantigenic epitopes is a key step in the autoimmune cascade. Epitope recognition takes place during the generation of tolerance, during its loss as the disease process is initiated, and during epitope spreading as islet cell damage is perpetuated. Epitope recognition is also a potentially critical element in therapeutic interventions such as antigen-specific immunotherapy. T cell epitope discovery, therefore, is an important component of type 1 diabetes research, in both human and murine models. With this in mind, in this review we present a comprehensive guide to epitopes that have been identified as T cell targets in autoimmune diabetes. Targets of both CD4 and CD8 T cells are listed for human type 1 diabetes, for humanized [human leucocyte antigen (HLA)-transgenic] mouse models, and for the major spontaneous disease model, the non-obese diabetic (NOD) mouse. Importantly, for each epitope we provide an analysis of the relative stringency with which it has been identified, including whether recognition is spontaneous or induced and whether there is evidence that the epitope is generated from the native protein by natural antigen processing. This analysis provides an important resource for investigating diabetes pathogenesis, for developing antigen-specific therapies, and for developing strategies for T cell monitoring during disease development and therapeutic intervention.
Agonistic antibodies to Fas induce a breach in the endothelial lining of the liver and a breakdown in B cell tolerance
Authors: Newkirk M M , Nowak U , Skamene E , Iera D , Desbarats J
Published: August 2010

Liver disease can be associated with a breakdown in self-tolerance and the production of autoantibodies such as rheumatoid factors (RF), which bind to IgG. Here we investigated whether primary, non-infectious liver damage was sufficient to induce autoantibody production. We established a model of targeted liver damage induced by weekly sublethal injections of pro-apoptotic anti-Fas (CD95) antibodies. Liver damage, monitored by measurements of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, was minimal 1 week after anti-Fas injection. However, the sublethal Fas stimulation was sufficient to trigger significant haemorrhage in the liver, as assessed by Evans Blue dye leakage into the organ 5 h after anti-Fas antibody injection. We observed an induction of RF in response to the weekly injections of sublethal anti-Fas antibodies but not of isotype control antibodies, indicating a breakdown of self-tolerance induced by Fas engagement. RF induction was unlikely to be due to direct activation of B cells, as splenocytes stimulated with anti-Fas antibodies in vitro did not produce RF. These studies show that sublethal damage to the liver by Fas engagement leads to liver haemorrhage and is sufficient to trigger the breakdown of self-tolerance.