bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of HLA and Insulin‐Dependent Diabetes Mellitus on the Secretion Levels of Tumour Necrosis Factors Alpha and Beta and Gamma Interferon
Authors: SACHS J. A. , WHICHELOW C. E. , HITMAN G. A. , NIVEN M. , THODE H. , MEAGER A. 
Published: June 2006

Tumour necrosis factors alpha and beta (TNF‐α and TNF‐β) and gamma interferon (IFN‐γ) were measured by ELISA in the supernatants of phytohaemagglutinin (PHA)‐activated peripheral blood mononuclear cells (PBMNC) from 98 individuals (60 controls and 38 patients with insulin‐dependent diabetes mellitus [IDDM]. The PBMNC were incubated with varying concentrations of PHA (0,1,5, and 10 μg/ml) for 72 h. In our population study we observed a correlation between the levels of secretion of TNF‐α and IFN‐γ but not TNF‐β. The complete data set was analysed by non‐parametric tests, and no associations with HLA phenotypes existed. Reduced levels of TNF‐β, but not TNF‐α or IFN‐γ, secretion were found in IDDM patients stimulated with 1 and 5 μg/ml of PHA (P ‐0.001 and 0.02 respectively). None of the lymphokine secretion levels at any PHA concentration correlated with particular HLA phenotypes.Analysis of the natural log‐transformed data indicated that only for the TNF‐β levels (at 5 μg/ml PHA) could subjects be divided into high and low secretors, which also did not correlate with a particular HLA‐B or ‐DR antigen.
SHORT PAPER
Authors: OHKUBO T. , TSUDA M. , TAMURA M. , YAMAMURA M. 
Published: June 2006

A method of separating neutrophils from the peripheral blood of rats with 95% purity is described. To determine the role of antigenic stimulation in neutrophil function, neutrophils front germ‐free (GF) rats were compared with those of conventional (CV) rats. Neutrophil counts were lower in GF rats but the total number of monocytic cells was the same.To measure phagocytic killing, superoxide anion production was determined and found to be lower in GF neutrophils (2.1 ± 0.5 nmol/min. 106 cells) than in CV neutrophils (9.5 ± 2.9 nmol/min/106 cells). Myeloperoxidase activity was found to be twofold higher in GF neutrophils. When a recombinant human granulocyte colony‐stimulating factor (rhG‐CSF) was intravenously injected, superoxide production did not change in either GF or CV neutrophils, but the myeloperoxidase activity of neutrophils in both types of rats decreased. rhG‐CSF increased the number of neutrophils in both GF (10‐fold) and CV rats (three‐ to fourfold).
Anti‐Granulocyte Antibodies (C‐ANCA, P‐ANCA, GS‐ANA) Studied by Confocal Scanning Laser Fluorescence Microscopy, ELISA, and Chemiluminescence Techniques
Authors: SKOGH T. , DAHLGREN C. , HOLMGREN K. , PEEN E. , STENDAHL O. 
Published: June 2006

Fifty‐nine patient sera with antibodies against human polymorphonuclear neutrophil granulocyte(PMN)antigens, as determined primarily by indirect immunofluorescence microscopy (UF) screening, were further analysed by enzyme‐linked Immunosorbent assays (ELISA). The antibodies were primarily characterized by their immunomorphological staining patterns on ethanol‐fixed PMN as judged by conventional IIF microscopy, i.e. anti‐neutrophil cytoplasmic antibodies (ANCA) giving a pancytoplasmic granular staining pattern (C‐ANCA) or a diffuse perinuclear cytoplasmic pattern (P‐ANCA), or granulocyte‐specific anti‐nuclear antibodies (GS‐ANA) producing a homogeneous or peripheral nuclear staining pattern. The three distinct patterns were confirmed by confocal scanning laser IIF microscopy.As antigen substrates in the ELISA tests we used an extract from azurophil PMN granules, myeloperoxidase (MPO), and lactoferrin. As expected, most (but not all) of the C‐ANCA positive sera turned out positive in the α‐ELISA assay. Both P‐ANCA and GS‐ANA positive sera had high frequencies of antibodies against MPO. Occasional P‐ANCA positive sera contained anti‐lactoferrin antibodies. Although P‐ANCA and GS‐ANA in general probably represent the same type of auto‐antibodies, we regard it appropriate to make a distinction between the two patterns, until the existence of‘true’granulocyte‐specific ANAs has been ruled out.All sera were analysed for their ability to activate PMN in vitro as judged by the generation of a chemiluminescence(CL) response. Sera containing C‐ANCA, as well as sera containing P‐ANCA or GS‐ANA, showed high frequencies of positive CL tests using‘resting’isolated PMN. The reactions were diminished, but not always abolished, by heat‐treatment of the sera.
Tumour Necrosis Factor‐α Induces Neutrophil‐Mediated Injury of Cultured Human Endothelial Cells
Authors: VON ASMUTH E. J. U. , LEEUWENBERG J. F. M. , VAN DER LINDEN C. J. , BUURMAN W. A. 
Published: June 2006

We investigated the ability of TNF‐α to mediate damage of endothelial cells in the presence of neutrophils. by measuring detachment of cultured human umbilical vein endothelial cells (HUVEC). Endothelial cell detachment was increased from 5% to about 75% by the presence of I‐10 ng/ml TNF‐α during incubation with neutrophils, whereas negligible endothelial cell lysis was observed as measured by 51Cr release. TNF‐α was compared with the cytokines IL‐lα and IFN‐γ and with PMA and LPS. Both TNF‐α and PMA appeared to be strong triggers for neutrophil‐induced endothelial cell detachment, whilst reduced injury was seen after addition of IL‐lα and LPS. IFN‐γ did not induce endothelial cell detachment, but potentiated the effect of both TNF‐α and IL‐lα. TNF‐α‐induced endothelial cell detachment was neutrophil dependent, since pre‐incubation of neutrophils, but not pre‐incubation of endothelial cells with TNF‐α, caused endothelial cell detachment. Thus, TNF‐α‐induced increase in neutrophil‐adhesiveness of HUVEC was found not to be essential for endothelial damage. Pre‐incubation of neutrophils in suspension with TNF‐α induced rapid activation, followed by nearly complete deactivation of neutrophils, as measured by their capacity to induce detachment of endothelial cells after removal of TNF‐α.These results indicate that local presence of TNF‐α might be critical in tissue or organ damage during early, neutrophil‐mediated inflammatory processes, independent of enhanced adhesiveness of endothelium for neutrophils.
Human MHC Class I Antigens are Associated with a 90‐kDa Cell Surface Protein
Authors: FERM M. T. , GRÖNBERG A. 
Published: June 2006

Human MHC class I proteins are expressed on almost all nucleated cells as a heavy chain (about 45 kDa) non‐covalently associated with β‐microglobulin (12 kDa), In this report we show that MHC class I (MHC‐I) proteins can also be associated with a 90‐kDa protein in the cell membrane.Surface‐radiolabelled cells were treated with dithiobis succinimidyl propionate (DSP) in order to preserve multimer protein complexes during cell lysis. The lysates were immunoprecipitated and analysed by SDS‐PAGE and autoradiography, Immunoprecipitation of human MH C‐ I proteins co‐precipitated another protein of about 90 kDa in molecular weight p90. p90wasco‐precipitaled from all the MIIC‐I expressing cells tested: WIT. Raji. Molt‐4 and IFN‐γ treated K562, but not from untreated, MHC‐I negative K562. A 90‐kDa protein was also co‐precipitated with MHC‐I from fresh peripheral blood mononueiear cells(PBMC). Furthermore, p90 was co‐precipitated by different MoAbs lo the MHC‐1 heavy chain or β2‐microglobulin. bul not by control antibodies. Two additional co‐precipitaling proteins al 34 kDa and 28 kDa were seen in MHC‐I precipitates from Raji cells.Our results suggest that MHC‐1 proteins and the 90‐kDa protein are associated in the cell membrane, probably by a close but weak, non‐covalent interaction. Two additional cell surface proteins at 34 kDa and 28 kDa seem to be MHC‐I associated on Raji Burkitt's lymphoma cells.
Lymphoproliferative Responses to Plasmodium falciparum Antigens in Children With and Without the Sickle Cell Trait
Authors: ABU‐ZEID Y A , ABDULHADI N. H. , HVIID L. , THEANDER T. G. , SAEED B. O. , JEPSEN S. , JENSEN J. B. , BAYOUMI R. A. 
Published: June 2006

Blood mononuclear cells (BMNC) were isolated from sickle cell trait (HbAS) healthy donors and normal haemoglobin (HbAA) healthy donors resident in a P. falciparum endemic area of eastern Sudan. Blood samples were collected during the malaria season. BMNC were tested for their proliferative responses to phytohaemagglutinin (PHA), purified protein derivative of tuberculin (PPD) and to soluble P. falciparum antigens (SPAg). Higher responses to SPAg and PPD were observed in the HbAS children compared with the HbAA children, whereas no differences were observed among adults of the two phenotypes. Proliferative responses to PHA were comparable in all individuals tested.The significance of these findings in relation to haemoglobin phenotype, age and the possible immunoregulatory mechanisms operating in HbAS and HbAA children during the malaria season is discussed.
Localization of Circulating Immune Complexes from Patients with Rheumatoid Arthritis in Murine Spleen Germinal Centres
Authors: MAGEED R. A. , KIRWAN J. R. , HOLBOROW E. J. 
Published: June 2006

In previous studies we have demonstrated high levels of rheumatoid factor (RF) and large‐size (> 22S) circulating immune complexes (CIC) in the serum of rheumatoid arthritis (RA) patients with extra‐articular disease. These findings were paralleled by a concurrent increase in the level of RF‐associated cross‐reactive idiotypes ICRI) and an apparent diversification of the RF repertoire detected in the serum of the same patients.In the present study we examine the ability of CICs to activate the complement system in vivo, and Us possible influence on expanding the RF repertoire in RA patients with extra‐articular disease. Activation of complement by CICs is the key for germinal centre localization and long‐term retention of such complexes on the surface of follicular dendritic cells (FDC). and so provides a source for the selection of cells with high affinity receptors for IgG and leads to the establishment or immunological memory.CICs containing different immunoglobulin isotypes and from different patients localized in mouse spleen germinal centres. However, intense localization was mainly seen for IgG‐containing complexes from the serum of patients with large‐size (> 22S) IgG RT complexes. T he ability of these complexes to localize in mouse spleen germinal centres was related to activation of the complement system via the classical pathway in the patients' sera. Localization of IgG complexes was significantly (P < 0.05) higher in sera from RA patients with extra‐articular disease than those with articular disease alone.This study demonstrates the ability of large‐size (>22S) IgG IgM RF complexes to activate complement and suggests a possible role for such complexes in modulating the immune response to IgG in RA patients with extra‐articular disease.
Fine Molecular Specificity of Linear and Assembled Antibody Binding Sites in HIV‐1 p24
Authors: HAAHEIM L. R. , MASKELL J. P , MASCAGNI P. , COATES A. R. M. 
Published: June 2006

A set of seven murine monoclonal antibodies were generated against a chemically synthesized 11‐kDa 104‐mer peptide covering the C‐terminal residues 270‐373 of the p24g.it; protein (HIV‐IBRU strain). All monoclonal antibodies recognized HIV‐LMN infected MOLT? cells by fluorescence und gave positive Western blot signals with viral gag peptides [p55 and/or p24), Oligopeptide binding regions were located with competitive enzyme‐linked immunosorbent assays. Detailed epitope scanning analyses (the Geysen technique) were performed by serological testing of the monoclonal antibodies against 99 overlapping hexapeptides which corresponded to the entire 104‐mer region. The antibodies bound to p24 peptide sequences located within the 275 2y3 and 351 36S regions. One antibody (LH 104‐B) which reacted with residues 357‐362 bound lo p55 alone. In contrast another antibody (LH 104–1). which recognized the residues 358–363. i.e. with five out of six residues in common with antibody LIIKM‐B for its epitope region, reacted exclusively with p24.At least two of the antibodies (LH104‐C and ‐A) which bound to p24 alone, apparently recognized conformational epitopes, They gave positive reactions with the regions 288—293/351–356 and 284–289/351–356, respectively.This work shows that chemical synthesis of large peptides is a viable alternative approach to immunochemical studies of viral proteins.
Immunological Screening of a Glycoprotein Antigen Expressed by Zajdela Ascites Hepatoma Cells on Normal Rat Tissues and Tumour Cells
Authors: NATO F. , GOULUT C. , MIRSHAHI M. , BOURRILLON R. 
Published: June 2006

Expression of the glycoprotein MII2 antigen originally identified in Zajdela ascites hepatoma cells was investigated in several normal rat tissues and in more or less differentiated tumours using biochemical and immunological approaches. SDS polyacrylamide gel electrophoresis followed by fluorography or immunoblotting with an antiserum raised against the purified MII2 antigen revealed that this antigen was absent from normal liver cells. ELISA assays, indirect immunofluorescence and immunoprecipitation experiments using the same antiserum showed that this glycoprotein was not expressed in various normal tissues such as liver, spleen, lung, pancreas, intestine and stomach, but it was unexpectedly detected in kidney and thymic (issues. However, the molecular weight of the antigens immunoprecipitated from kidney and thymus was lower than the one of MH2 (Mr of 60.000 versus 110,000 160,000 for purified MH2). No staining was observed in embryonic rat liver at 10 and 20 days of development.Moreover, this antigen was present on the surface of Morris hepatoma 7777, another rapidly proliferating and poorly differentiated hepatocellular carcinoma. In contrast, this antigen was not detected on the surface of in vitro Zajdela hepatoma cells (ZHC) or of partially differentiated hepatomas (Faza) which have recovered some hepatic functions. In addition, the MH2: antigen was found on the human non‐hepatic HT‐29 tumour cell line, under its undifferentiated form (HT‐29 G’ subline). The possible relationships between the expression of this antigen and both the malignant transformation process and the differentiation process are discussed.
T‐Helper‐Cell Determinants in Protein Antigens are Preferentially Located in Cysteine‐Rich Antigen Segments Resistant to Proteolytic Cleavage by Cathepsin B, L, and D
Authors: MOURITSEN S. , MELDAL M. , RUUD‐HANSEN J. , WERDELIN O. 
Published: June 2006

We report on a computer algorithm capable of predicting the location of T‐helper‐cell epitopes in protein antigen (Ag) by analysing the Ag amino acid sequence. The algorithm was constructed with the aim of identifying segments in Ag which are resistant to proteolytic degradation by the enzymes cathepsin B, L, and D. These are prominent enzymes in the endocytic pathway through which soluble protein Ag enter APC, and resistant segments in Ag may, therefore, be expected to contain more T‐cell determinants than susceptible segments.From information available in the literature on the substrate specificity of the three enzymes, it is clear that a cysteine is not accepted in any of the S2, S1, S1′, and S2' subsites of cathepsin B and L, and not in the S1 and S1' subsites of cathepsin D. Moreover, we have noticed that cysteine‐containing T‐cell determinants in a number of protein Ag are particularly rich in the amino acids alanine, glycine, lysine, leucine, serine, threonine, and valine. By searching protein Ag for clusters of amino acids containing cysteine and two of the other amino acids we were able to predict 17 out of 23 empirically known T‐cell determinants in the Ag with a relatively low number of false (positive) predictions.Furthermore, we present a new principle for searching Ag for potential amphipatic α‐helical protein segments. Such segments accord well with empirically known T‐cell determinants and our algorithm produces a lower number of false positive predictions than the principle based on discrete Fourier transformations previously described.
Functional Epitope Analysis of the Human CD 11 a/CD 18 Molecule (LFA‐1, Lymphocyte Function‐Associated Antigen 1) Involved in HIV‐1‐Induced Syncytium Formation
Authors: VERMOT‐DESROCHES C. , RIGAL D. , ESCAICH S. , BERNAUD J. , PICHOUD C. , LAMELIN J.‐P. , TREPO C. 
Published: June 2006

After binding lo the CD4 receptor, the human Immunodeficiency virus I HIV‐I)may enter the T cell and induce the formation of multinucleated giant cells (syncytia). As well as the CD4 molecule, other molecules, such as the lymphocyte function‐associated antigen 1(LFA‐1. CD11a/CD 18) have been shown to be involved in HIV‐l‐mediated cell fusion.This study was designed to define regions on the human CD1la/CD18 molecule important for the HIV‐l‐induced syncytium formation A CD11a/CD18 MoAb panel discriminating at least five distinct and spatially distant domains of the LFA‐l molecule was used. Comparison of the functional activity of different MoAbs demonstrated that all epitopes of the LFA‐1 molecule were not of equal importance m HIV‐1‐induced syncytium formation between H9.III cells chronically infected with HIV‐1 and uninlecledCD4+ Sup T1 cells. We also demonstrated that CD11a/CD18 MoAbs inhibit syncytia formation only at the level of the uninfected Sup T1 cells, suggesting that the LPA‐1 molecule expressed on Sup T1 ceils interacts with ligand(s) expressed on the infected H9. III cells. Two potential LFA‐1 receptors on the H9.III cells were tested: t he ICAM‐1 molecule (intercellular adhesion molecule 1.CD54)and the HIV‐1 transmembrance glycoprotein41 (gp4l), A CD54 MoAb (84H10) partially inhibited syncytia formation, thus demonstrating the involvement of the ICAM‐1 molecule in the HIV‐l‐mediated cell fusion. However, the CD11a/CD18 MoAbs do not inhibit binding of the viral envelope glycoprotein gp41 to the cell surface, irrespective of the MoAb concentration used.Although we have not been successful in identifying all candidate fusion receptors for the LFA‐1 molecule, these data suggest that some LFA.‐1 regions are important for syncytium formation and. therefore, in the cell‐to‐cell transmission of virus and in the spread of infection.
Human Monoclonal Antibodies against Blood Group Antigens Preferentially Express a VH4‐21 Variable Region Gene‐Associated Epitope
Authors: THOMPSON K. M. , SUTHERLAND J. , BARDEN G. , MELAMED M. D. , RANDEN I. , NATVIG J. B. , PASCUAL V. , CAPRAJ J. D. , STEVENSON F. K. 
Published: June 2006

An anti‐idiotypic antibody has been raised which recognizes human immunoglobulins with cold agglutinin activity of anti‐I/i specificity. The pattern of reactivity of the antibody indicates that the structural basis for the epitope is located in the VH4‐21 gene segment of the VHIV family, which is preferentially utilized by these cold reactive antibodies.Using this antibody, epitope expression was investigated in a panel of 72 human monoclonal allo‐antibodies specific for human blood group antigens, as compared with a control panel of 39 randomly selected human monoclonal IgM antibodies of unknown specificities. The anti‐blood group panel included 44 IgM and 28 IgG monoclonal antibodies against a variety of blood group antigens including the A antigen, Rh C, c, D, E, e, G antigens, and the Kidd antigens Jka and Jkb. The epitope was expressed by 64% (28/44) of the IgM anti‐blood group antibodies and by 21 % (6/28) of the IgG antibodies, but by only 7.7% (3/39) of the control IgM antibodies.These data indicate that the human alloimmune response to blood group antigens is biased in the use of VH gene families, with a preference for the VH4‐21 gene segment of the VHIV family, or closely related gene segments. The fact that this mirrors the findings for the autoimmune cold agglutinins suggests a link in immunoglobulin gene usage between antibodies against structurally diverse antigens on the red cell surface.
Monoclonal Antibody Treatment (Anti‐CD4 and Anti‐Interleukin‐2 Receptor) combined with Cyclosporin A has a Positive but not Simple Dose‐Dependent Effect on Rat Renal Allograft Survival
Authors: STEINBROCHEL D. A. , KOCH C. , RISTENSEN T. K , KEMP E. 
Published: June 2006

The use of monoclonal antibodies (MoAbs) in experimental and clinical organ transplantation is of increasing interest since this treatment seems to offer an opportunity for specific immunomodulation.In a rat kidney allograft model. Cyclosporin A (CyA) treatment (12.5 mg/kg/d, day 0–14) was combined with murine anti‐rat CD4 (MRC OX‐38) and murine anti‐rat IL‐2R (MRC OX‐39) MoAbs at doses of i00 or 300μg;kg/d (day 0–7) and plasma concentrations of the murine MoAb were determined.In both groups receiving combined treatment with CyA and MoAb, graft survival was prolonged to an average of 65 days, compared to a graft survival of 9–10 days in non‐treated recipients. Further, the data showed a beneficial effect of CyA + MoAb treatment versus CyA alone (graft survival 32 days). The threefold increased MoAb dose did not seem to improve graft survival or function. Treatment with OX‐38 + OX‐39 at a dose of 100 μg/kg/d each resulted in plasma levels of 280 ng/ml 14 days after transplantation. Corresponding values after the administration of 300 μg/kg/d were 1800 ng/ml in graft recipients as well as controls.These findings indicate that the effect of MoAbs in complex organ transplantation models is not simply dose dependent and that in vitro assays are of limited value in predicting the effect of a given MoAb when used in vivo. The determination of MoAb plasma levels, however, may be a useful tool in defining optimal MoAb administration and to monitor therapeutically effective plasma levels.
Stimulation of Peripheral Blood T Cells by an Activated T‐Cell Line: a Novel Human Autologous T‐T Lymphocyte Reaction
Authors: DITZIAN‐KADANOFF R. , PARKS L. , EVAVOLD B. , QUINTANS J. , SWARTZ T. J. 
Published: June 2006

T lymphocyte interactions have generally been described between discrete functional subsets. In our investigation of murine T‐cell interactions we described a type of T‐T interaction termed the 'Syngeneic T‐T Lymphocyte Reaction’in which activated T‐cell clones stimulated the proliferation of resting T cells mainly through a mechanism involving cell to cell contactTo investigate whether similar reactions occur in the human immune system we used the human autoreactive T‐cell line C.1 to stimulate peripheral T cells. Line C! cells, which are not transformed and do not secrete IL2. consistently caused proliferation of purified freshly isolated autologous peripheral human T cells as measured by a [3H]‐thymidine incorporation assay. The proliferation was seen in both the CD4and CDS subsets and could be inhibited with anti‐DR and anti‐CD2 antibodies. The stimulation is not due to carryover of classical antigen‐presenting cells or to the C.1 line cells acting as antigen‐presenting cells.We propose that some activated T cells, probably by expression of a surface molecule, can stimulate resting T cells thereby allowing for antigen‐non‐specific augmentation of the immune response.