bluuebunny/crossref_metadata_2025_split huggingface dataset:
A thiol proteinase inhibitor, E-64-d, corrects the abnormalities in concanavalin A cap formation and the lysosomal enzyme activity in leucocytes from patients with Chediak–Higashi syndrome by reversing the down-regulated protein kinase C activity
Authors: Cui S-H , Tanabe F , Terunuma H , Iwatani Y , Nunoi H , Agematsu K , Komiyama A , Nomura A , Hara T , Onodera T , Iwata T , Ito M 
Published: March 2003

SummaryWe have reported previously that the abnormally down-regulated protein kinase C (PKC) causes cellular dysfunction observed in natural killer (NK) cells, polymorphonuclear leucocytes (PMNs) and fibroblasts from beige mouse, an animal model of Chediak–Higashi syndrome (CHS). Here we show that the abnormal down-regulation of PKC activity also occurs in Epstein–Barr (EB) virus-transformed cell lines from CHS patients. When CHS cell lines were stimulated with concanavalin A (Con A) for 20 min, the membrane-bound PKC activity declined markedly, whereas that in control cell lines increased. We found that E-64-d, which protects PKC from calpain-mediated proteolysis, reversed the declined PKC activity and corrected the increased Con A cap formation to almost normal levels in CHS cell lines. We confirmed that the dysregulation of PKC activity also occurred in peripheral blood mononuclear leucocytes (PBMC) from CHS patients and that E-64-d corrected both the declined PKC activity and increased Con A cap formation. E-64-d also corrected the reduced lysosomal elastase and cathepsin G activity in CHS cell lines. In contrast, chelerythrin, a specific inhibitor of PKC, and C2-ceramide, which promotes PKC breakdown induced by calpain, increased Con A cap formation and inhibited both elastase and cathepsin G activity in normal cell lines. Moreover, we found that ceramide production in CHS cell lines increased significantly after Con A stimulation, which coincides with our previous observation in fibroblasts from CHS mice. These results suggest an association between ceramide-induced PKC down-regulation and the cellular dysfunctions in CHS.
Influence of the IL-1Ra gene polymorphism on in vivo synthesis of IL-1Ra and IL-1β after live yellow fever vaccination
Authors: Hacker U T , Erhardt S , Tschöp K , Jelinek T , Endres S 
Published: March 2003

Summary
The inflammatory response in infectious and autoimmune diseases is regulated by the balance between pro- and anti-inflammatory cytokines. The IL-1 complex contains polymorphic genes coding for IL-1α, IL-1β and IL-1Ra. The IL-1Ra (variable number of tanden repeat) VNTR polymorphism has been shown to influence the capacity to produce IL-1β and IL-1Ra after in vitro stimulation. Allele 2 of this polymorphism is associated with a number of inflammatory diseases. To determine the impact of the IL-1Ra polymorphism on in vivo human cytokine synthesis, we used a yellow fever vaccination model for the induction of cytokine synthesis in healthy volunteers. Two different yellow fever vaccines were used. After administration of the RKI vaccine (34 volunteers), plasma TNF-α concentration increased from 13·4 ± 0·9 pg/ml to 23·3 ± 1·1 pg/ml (P &lt; 0·001), and plasma IL-1Ra concentration increased from 308 ± 25 pg/ml to 1019 ± 111 pg/ml (P &lt; 0·001), on day 2. Using Stamaril® vaccine, no increase in the plasma concentrations of either TNF-α or IL-1Ra could be detected (n = 17). Only the RKI vaccine induced TNF-α synthesis after in vitro stimulation of MNC. Carriers of allele 2 of the IL-1Ra polymorphism had increased baseline concentrations of IL-1Ra (350 ± 32 pg/ml) compared with non-carriers (222 ± 18 pg/ml, P &lt; 0·001), and decreased concentrations of IL-1β (0·9 ± 0·2 pg/ml for carriers versus 2·8 ± 0·7 pg/ml for non-carriers, P = 0·017). After yellow fever vaccination (RKI vaccine), no significant differences in the increase of IL-1Ra plasma levels were detected between carriers and non-carriers of allele 2 of the IL-1Ra gene polymorphism. This is the first study to examine the influence of this genetic polymorphism on in vivo-induced human IL-1β and IL-1Ra synthesis. Baseline concentrations of IL-1Ra and IL-1β were significantly influenced by the IL-1Ra polymorphism. No influence of the IL-1Ra polymorphism on the in vivo-induced production of IL-1Ra and IL-1β could be detected.
Down-regulation of CXCR1 and CXCR2 expression on human neutrophils upon activation of whole blood byS. aureusis mediated by TNF-α
Authors: Tikhonov I , Doroshenko T , Chaly Y , Smolnikova V , Pauza C D , Voitenok N 
Published: March 2003

SummaryIt was suggested that bacterial products can inhibit the expression of leucocyte chemokine receptors during sepsis and affect leucocyte functions in septic syndrome. Superantigens and toxins produced by Staphylococcus aureus are capable of activating leucocytes via binding to MHC-II antigens on monocytes and T-cell receptor molecules on T lymphocytes. It was recently shown that staphylococcal enterotoxins directly down-regulate the expression of CC chemokine receptors on monocytes through binding to MHC class II molecules. We studied the effects of killed S. aureus on the expression of interleukin-8 receptors, CXCR1 and CXCR2, on polymorphonuclear leucocytes (PMN), which are known to lack the expression of MHC-II antigens. It was shown that S. aureus down-regulated the cell-surface expression of CXCR1 and CXCR2 on PMN in the whole blood and total blood leucocyte fraction containing PMN and monocytes, but did not modulate IL-8 receptor expression in purified PMN suspension. Antibody to TNF-α abrogated down-regulation of IL-8 receptors induced by S. aureus. In contrast, LPS reduced CXCR1 and CXCR2 expression in purified PMN and whole blood in a TNF-α-independent manner. We further showed that TNF-α-induced decrease of CXCR1 and CXCR2 expression was associated with lower IL-8 binding and lower CXCR1 and CXCR2 mRNA levels, and was abrogated by protease inhibitors. We suggest that during septicemia, S. aureus may inhibit neutrophil responsiveness to IL-8 and other CXC chemokines via TNF-α- mediated down-regulation of CXCR1 and CXCR2.
Recurrent miscarriage and variant alleles of mannose binding lectin, tumour necrosis factor and lymphotoxinαgenes
Authors: Baxter N , Sumiya M , Cheng S , Erlich H , Regan L , Simons A , Summerfield J A 
Published: March 2003

SummaryVariant alleles of the mannose binding lectin (MBL) gene are associated with increased susceptibility to infection and polymorphisms of tumour necrosis factor and lymphotoxin alpha genes (TNF, LTA) are associated with increased severity of infection. Studies have associated recurrent miscarriage with low serum mannose binding lectin concentrations and premature membrane rupture and preterm delivery with elevated maternal and fetal levels of TNF and the TNF (− 308) polymorphism. In this study the frequencies of variant MBL, TNF and LTA alleles in 76 Caucasian couples with idiopathic recurrent miscarriage were compared with those in 69 Caucasian control couples with no history of miscarriage and at least one previous live birth. A new assay based on hybridization to immobilized sequence-specific oligonucleotides (SSO) was used to rapidly detect nine MBL, two TNF and two LTA sequence variants. The assay genotyped all the structural and promoter MBL variants known to influence serum MBL concentrations. This assay was more reliable than restriction digestion or nested allele-specific PCR for the structural variants at codon 54 or 52, respectively. Reliability for codon 57 alleles was not assessed because of the low frequency in this population. The MBL haplotype frequencies in antenatal controls were similar to those reported in other control populations. The frequencies of structural variant MBL genes and of low, medium and high MBL level haplotypes were similar in the recurrent miscarriage and control couples. The TNF and LTA haplotype frequencies were similar in the recurrent miscarriage and control couples. In this carefully defined population no association has been found between recurrent miscarriage and variant alleles of the MBL, TNF or LTA genes.
Regulation of rheumatoid synoviocyte proliferation by endogenous p53 induction
Authors: Migita K , Tanaka F , Yamasaki S , Shibatomi K , Ida H , Kawakami A , Aoyagi T , Kawabe Y , Eguchi K 
Published: March 2003

Summary
The p53 tumour suppressor protein protects cells from tumorigenic alterations by inducing either cell growth arrest or apoptosis. In the present study, we investigated the role of endogenous p53 expressed in rheumatoid arthritis synovial fibroblasts which show transformed-appearing phenotypes. Type B synovial cells (fibroblast-like synovial cells) were exposed to a proteasome inhibitor, carbobenzoxyl-leucinyl-leucinyl-leucinal (MG-132). During this process, the expressions of p53 and p21 were examined by Western blot. Cell cycle analysis of the synovial cells was determined by DNA staining using propidium iodide (PI). Inhibition of proteasome resulted in the accumulation of p53 which was followed by an increase in the amount of a cyclin-dependent kinase (CDK)-inhibitor, p21. As a consequence, the retinoblastoma gene product, Rb, remained in the hypophosphorylated state, thus preventing PDGF-stimulated synovial cells from progressing into S-phase. This study shows that endogenous p53, which is inducible in rheumatoid synovial cells, is functionally active based on the findings that its expression blocks the G1/S transition by inhibiting the CDK-mediated phosphorylation of Rb via p21 induction. Thus the induction of p53 using proteasome inhibitor may provide a new approach in the treatment of RA.
Surface expression of CC- and CXC-chemokine receptors on leucocyte subsets in inflammatory joint diseases
Authors: Brühl H , Wagner K , Kellner H , Schattenkirchner M , Schlöndorff D , Mack M 
Published: March 2003

SummaryChemokine receptors play a crucial role in the recruitment of leucocyte subsets into inflamed tissue. Using FACS analysis we have studied the surface expression of different CC- and CXC-chemokine receptors on synovial fluid (SF) and peripheral blood leucocytes from 20 patients with various forms of arthritis. In the SF the majority T cells stained positive for CCR5 (93%) and CCR2 (57%), compared to the peripheral blood (36% and 25%). In addition, most of the T cells expressed CXCR4 in both compartments, with a somewhat higher percentage in the SF (90%) versus peripheral blood (83%). To date little information is available on chemokine receptor expression on monocytes in arthritis. We report a marked increase of CCR5+ monocytes in the SF (87%) compared to the peripheral blood (22%). In contrast, the frequency of CXCR1+, CXCR2+, CXCR4+ and CCR1+ monocytes was considerably lower in the SF than in the peripheral blood. Moreover, we report the expression CXCR4 on neutrophils in the SF. Approximately 60% of neutrophils stained positive for CXCR4 in the SF, while in the peripheral blood the number of CXCR4+ neutrophils was low (24%). Surface expression of CXCR1 and CXCR2 was significantly reduced on SF neutrophils (53% and 68%) compared to the peripheral blood. Chemokine receptors are differentially expressed on leucocyte subsets in arthritis. The identification of their pattern of expression might help to identify suitable targets for therapeutic intervention.
Characterization of thoracic duct cells that transfer polyarthritis
Authors: Spargo L D J , Cleland L G , Wing S J , Hawkes J S , Mayrhofer G 
Published: March 2003

SummaryPolyarthritis may result from the haematogenous distribution of arthritogenic effector lymphocytes that emerge in the efferent lymph and pass through the thoracic duct (TD) to the circulation. We therefore examined whether TD cells collected from rats in the late prodrome of adjuvant-induced arthritis (AA) could transfer polyarthritis adoptively and whether these cells included a subpopulation of arthritogenic cells that could be identified phenotypically. Unfractionated TD cells collected from donor rats 9 days after adjuvant inoculation were injected intravenously into normal syngeneic recipients in numbers equivalent to the overnight harvest from a single donor. TD cell subpopulations, equivalent in number to proportions in the same inoculum, were prepared by negative selection. Unfractionated TD cells transferred polyarthritis without in vitro stimulation or conditioning of recipient animals. Abrogation of arthritogenicity by depletion of α/β TCR+ cells showed that the polyarthritis was transferred by T cells. Negatively selected CD4+ but not CD8+ TD cells transferred AA. An arthritogenic subpopulation of CD4+ T cells, enriched by either negative or positive selection, expressed the activation markers CD25 (IL-2 receptor alpha), CD71 (transferrin receptor), CD134 (OX40 antigen) and MHC class II. Cells expressing these markers were more numerous in TD lymph from arthritic rats than in lymph from normal rats and they included the majority of large CD4+ T cells. Thus, arthritogenic effector T cells bearing activation markers are released into the central efferent lymph in the late prodrome of AA. Recruitment of these arthritogenic cells to synovium probably determines the polyarticular pattern of AA.
Complement C4 monitoring in the follow-up of chronic hepatitis C treatment
Authors: Dumestre-Perard C , Ponard D , Drouet C , Leroy V , Zarski J-P , Dutertre N , Colomb M G 
Published: March 2003

SummaryThe overall role of complement in the host–pathogen relationship is now well understood. However, its involvement at a chronic stage of infection, such as chronic hepatitis C, is less well documented. Here, results are reported which point to the use of specific C4 monitoring in the follow-up of HCV patients. This study concerns 66 patients with chronic HCV infection, treated with interferon alpha 2b alone or with interferon alpha 2b + ribavirin, and 50 healthy adults as controls. Complement blood tests were performed to measure C1q, C3, C4, mannan binding lectin (MBL), C1s-C1 inhibitor complexes, total (CH50) and C4 (C4H) haemolytic activity; specific C4 activity was taken as the C4H/C4 protein ratio. Rheumatoid factor (RF) levels were also measured. A significant reduction in CH50 and specific C4 activity in HCV patients, compared with the healthy controls, was observed before the onset of treatment; the other parameters were not affected and no C1s-C1 inhibitor complexes were detected. At the same time, a significant reduction in specific C4 activity was observed in relapsers compared with sustained responders. These results point to a potential predictive function of C4 specific activity to monitor the response to therapy. Restoration of specific C4 activity at 6 months was better in responders than in non-responders. Complement activation in chronic hepatitis C does not seem to involve the C1 stage of the classical pathway. A negative correlation between specific C4 activity and RF titres suggests a possible involvement of RF in C4 activation, via the lectin pathway. Specific C4 monitoring appears to be a valuable tool for the follow-up of chronic hepatitis C treatment, together with the other conventional investigations.
Reduced efficacy of treatment of strongyloidiasis in HTLV-I carriers related to enhanced expression of IFN-γ and TGF-β1
Authors: SATOH M , TOMA H , SATO Y , TAKARA M , SHIROMA Y , KIYUNA S , HIRAYAMA K 
Published: March 2003

SummaryStrongyloidiasis, a human intestinal infection caused by Strongyloides stercoralis (S. stercoralis), is difficult to cure with drugs. In particular, a decrease of the efficacy of treatment has been reported in patients dually infected with S. stercoralis and human T-cell leukaemia virus type I (HTLV-I), both of which are endemic in Okinawa, Japan. However, the factors influencing this resistance remain unclear. In the present study, patients infected with S. stercoralis, with or without HTLV-I infection, were treated with albendazole, followed up for one year and separated into two groups, cured and non-cured. The cure rate of S. stercoralis was lower in HTLV-I carriers (P &lt; 0·05). Serum levels of S. stercoralis-specific IgA, IgE, IgG, IgG1 and IgG4 antibodies were estimated, and a decrease of IgE (P &lt; 0·05) and an increase of IgG4 (P &lt; 0·05) were observed in the non-cured group, especially in HTLV-I carriers. RT-PCR of cytokines using peripheral blood mononuclear cells revealed that S. stercoralis patients with HTLV-I showed a high frequency of expression of IFN-γ and TGF-β1, whereas those without HTLV-I showed no expression of these cytokines. IFN-γ- and TGF-β1-positive HTLV-I carriers showed a decrease of IgE (P &lt; 0·05), an increase of IgG4 (P &lt; 0·01) and a lower cure rate (P &lt; 0·01) compared with those who were negative for both cytokines. These results suggest that persistent infection with HTLV-I affected S. stercoralis-specific immunity and reduced therapeutic efficacy.
Autoantibodies against cytochrome P450s in sera of children treated with immunosuppressive drugs
Authors: LYTTON S D , BERG U , NEMETH A , INGELMAN-SUNDBERG M 
Published: March 2003

Summary
Treatment with the immunosuppressive drugs cyclosporin and tacrolimus, the mainstays of anti-graft rejection and autoimmune disease therapy, is limited by their hepato- and nephrotoxicity. The metabolic conversion of these compounds to more easily excretable products is catalysed mainly by hepatic cytochrome P4503A4 (CYP3A4) but also involves extrahepatic CYP3A5 and other P450 forms. We set out to study whether or not exposure to cyclosporin and FK506 in children undergoing organ transplantation leads to formation of autoantibodies against P450s. Immunoblotting analysis revealed anti-CYP reactivity in 16% of children on CyA for anti-graft rejection or treatment of nephrosis (n = 67), 31% of kidney transplant patients switched from CyA to FK506 (n = 16), and 21% of kidney and or liver transplant patients on FK506 (n = 14). In contrast, the frequency of reactive immunoblots was only 8·5% among the normal paediatric controls (n = 25) and 7% among adult kidney transplant patients on CyA or FK506 (n = 30). The CYP2C9+ sera were able to immunoprecipitate in vitro translated CYP2C9 and the immunoblot reactivity showed striking correlation to peaks in the age at onset of drug exposure. Sera were isoform selective as evidenced from Western blotting using human liver microsomes and heterologously expressed human P450s. These findings suggest that anti-cytochrome P450 autoantibodies, identified on the basis of their specific binding in immunoblots, are significantly increased among children on immunosuppressive drugs and in some cases are associated with drug toxicity and organ rejection.
Leucocyte chemotaxis: Examination of mitogen-activated protein kinase and phosphoinositide 3-kinase activation by Monocyte Chemoattractant Proteins-1, -2, -3 and -4
Authors: WAIN J H , KIRBY J A , ALI S 
Published: March 2003

SUMMARYMonocyte Chemoattractant Proteins (MCPs) form a distinct, structurally-related subclass of CC chemokines. They are major chemoattractants for monocytes and T lymphocytes. The MCPs bind to specific G-protein-coupled receptors, initiating a signal cascade within the cell. Though the signal transduction pathways involved in MCP-1-mediated chemotaxis have been studied, the signalling pathways through which MCP-2, -3 and -4 trigger cell migration are not established. In this study, we examined the mitogen-activated protein kinase (MAPK) activation elicited by the MCPs (1–4) and its specific role in chemotaxis. Within 2 min, the MCPs (1–4) elicited a rapid and transient activation of MAPK in peripheral blood mononuclear cells and in HEK-293 cells expressing CCR2b. U0126, an inhibitor of MAPK-kinase (MEK) activation, not only prevented extracellular signal-regulated kinase 1/2 (ERK1/2) activation but also significantly inhibited the MCP-mediated chemotaxis. PI3K inhibitors Wortmannin and LY294002 also partially inhibited the MCP-induced chemotaxis. However, these compounds did not significantly inhibit ERK1/2 activation. As PI3K inhibitors partially inhibit the MCP-mediated chemotaxis but do not significantly effect ERK1/2 activation, these data suggest that co-ordinated action of distinct signal pathways is required to produce chemokine-mediated chemotaxis.
Transgenic models of autoimmune disease
Authors: Boyton R J , Altmann D M 
Published: March 2003

SummaryTransgenic and knockout mouse models have been invaluable for the elucidation of basic mechanisms in autoimmunity and have contributed new experimental models of human autoimmune diseases. Transgenic models of self tolerance have helped to change our view of this state from a process mediated purely by thymic deletion to a more complex process encompassing deletion, peripheral anergy, down-regulation of receptors and modulation by regulatory cells. Experiments in which the genes for the candidate target antigens in autoimmune disease are over-expressed or under-expressed have helped to clarify the targets of attack. Several examples of T cell receptor transgenic mice have been described in which T cells carry the receptor derived from a human or mouse autoimmune T cell clone. Such mice allow the characterization of T cell specificities contributing to disease and of the additional factors and checkpoints influencing disease development. In addition, the expression of disease associated HLA alleles in ‘humanised’ transgenic lines allows the mapping of HLA-restricted T cell epitopes and investigation of the mechanisms underlying these genetic associations. These approaches are leading to the generation of new disease models, offering hope for the design and testing of novel immunotherapeutic strategies.
Plasma levels of soluble endothelial cell protein C receptor in patients with Wegener's granulomatosis
Authors: BOOMSMA M M , STEARNS-KUROSAWA D J , STEGEMAN C A , RASCHI E , MERONI P L , KUROSAWA S , TERVAERT J W COHEN 
Published: March 2003

SUMMARY
Elevated soluble thrombomodulin (sTM) levels are an accepted marker of endothelial damage. The physiological significance of plasma endothelial protein C receptor (sEPCR) levels is not known. To assess the relevance of this plasma protein in Wegener's granulomatosis (WG), sEPCR levels were measured in sera obtained from WG patients and related to disease activity, sTM levels, and other known markers of disease activity. In total, 129 sera (37 at active disease, 92 during follow-up) from 31 WG patients were tested. During active disease, eight (22%) and 17 (46%) out of 37 active sera had elevated levels of sEPCR and sTM, respectively (NS); sEPCR (r = 0·39; P = 0·02) and sTM (r = 0·53; P &lt; 0·01) levels correlated with disease activity (Birmingham Vasculitis Activity Score). Analysis of longitudinal sera revealed a significant increase in sEPCR (P = 0·01) and sTM (P = 0·04) levels prior to the moment of a relapse. Corrected for renal function, the increase in sEPCR remained significant (P = 0·04) whereas sTM did not (NS). Levels of sEPCR correlated with sTM levels (r = 0·32; P &lt; 0·001). Plasma levels of sEPCR respond to changes in the disease in patients with WG.