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S T Lillevang

Publications and source records attributed to S T Lillevang.

At least 19 recordsLinked to original sources
PubMed2007

Expression of human PTPN22 alleles.

Considering the female predominance in most of the autoimmune disorders that associate with the PTPN22 Trp620 variant and the complexity by which this variant influences immunologic tolerance, the objective of this study was to ascertain if the allele-specific expression of the disease-associated Arg620Trp polymorphism is affected by cis-acting or sex-specific trans-acting factor/s (e.g. sex-hormones). The use of the allele-specific transcript quantification of the Arg620Trp encoding 1858T polymorphism revealed no difference in the expression of the 1858C- and T-alleles in non-stimulated peripheral blood mononuclear cells (PBMCs) from non-pregnant female subjects, male subjects or pregnant female subjects in first or third trimester (P=0.70), respectively. While the transcription of PTPN22 in anti-CD3/anti-CD28 stimulated PBMCs increased fourfold (P<0.0001) and 13-fold (P<0.0001) after 48 and 72 h of activation, respectively, the expression of PTPN22 1858C- and T-alleles increased to the same extent (P=0.64). The present result essentially excludes such phenomena as a partial explanation for the female predominance in most of the autoimmune disorders that associate with the PTPN22 Trp620 variant.

Alleles↗
PubMed2006

Peroxisome proliferator-activated receptor alpha, delta, gamma1 and gamma2 expressions are present in human monocyte-derived dendritic cells and modulate dendritic cell maturation by addition of subtype-specific ligands.

It has recently been shown by Chang et al. (J Immunol 2000;165:3584-91) that the maturation of dendritic cells (DC) in the presence of long-chain fatty acids redirects DC into Th0/Th2-inducing cells suggesting the involvement of a receptor for long-chain fatty acids like members of the peroxisome proliferator-activated receptors (PPAR) superfamily. Here, we show that immature and mature monocyte-derived DC (Mo-DC) express PPARalpha, PPARdelta, PPARgamma1 and PPARgamma2 mRNA with the highest level of PPARgamma1 mRNA. We were only able to observe the expression of PPARgamma1 protein by Western blotting probably because the protein level of the other subtypes is below the detection limit. Synthetic ligands specific for PPARalpha, PPARdelta or PPARgamma added at day 0-6 have similar effect on the maturation of Mo-DC driving the maturation of Mo-DC with atypical phenotype, reduced expression of IL-10, IL-12 p35 and IL-12 p40 mRNA and with reduced stimulatory effects in mixed leucocyte reaction (MLR). Our data suggest that naturally occurring PPAR ligands like fatty acids and fatty acid derivates have anti-inflammatory effects by redirecting DC into a less stimulatory mode.

Cell Differentiation↗
PubMed2004

Serum concentration of the growth medium markedly affects monocyte-derived dendritic cells' phenotype, cytokine production profile and capacities to stimulate in MLR.

We have investigated how the maturation of monocyte-derived dendritic cells (Mo-DC) is affected by the serum concentration of the culture medium. Day 6 DC cultured in 1% human serum were a heterogeneous population of CD1a(-) and CD1a(+) DC that were separated by flow sorting. In contrast, Mo-DC generated in 10% human serum formed a homogenous population of CD1a(-) cells. Other phenotypically immature characteristics also varied, and three subsets were still distinguishable upon maturation in LPS. Furthermore, CD1a(-) DC and CD1a(+) DC from 1% culture conditions were excellent stimulators in MLR, while DC cultured in 10% serum were poor stimulators. Similarly, different cytokine profiles of the three subsets were identified. DC cultured in 1% serum had low expression of interleukin-12 (IL-12) p40 and IL-10 mRNA at day 6. Upon maturation, expression of IL-12 p40 mRNA was upregulated in CD1a(+) DC, whereas the level remained relatively low in CD1a(-) DC. In contrast, DC cultured in 10% had high levels of IL-10 mRNA at day 6 that was downregulated upon maturation. We conclude that the differentiation of monocytes into DC is significantly influenced by the serum concentration of the growth medium with effects on phenotype, cytokine profile and stimulatory activity.

Culture Media↗
PubMed2004

A putative regulatory polymorphism in PD-1 is associated with nephropathy in a population-based cohort of systemic lupus erythematosus patients.

The association between polymorphisms in the programmed death (PD-1) gene and susceptibility to systemic lupus erythematosus (SLE) was determined using genomic DNA, isolated from a population-based cohort of 95 SLE patients and 155 healthy controls. Polymorphisms in the complete PD-1 gene except the large intron 1 were detected by sequencing. Furthermore, the patients were stratified according to the presence or absence of lupus nephropathy. The influence of the detected single nuclear polymorphisms (SNPs) on this specific clinical disease parameter was determined. In total, we identified 12 single nucleotide polymorphisms, of which six were novel and eight were considered to be rare (the frequency of the minor allele of these was less than 1% in our study populations). We found a significant association of an intronic 6867C/G SNP in the PD-1 gene with the presence of lupus nephropathy. As the 6867C/G SNP is located in a putative binding site for the transcriptional repressor ZEB, the associated allele of this SNP potentially alters the transcriptional regulation of PD-1. This report, for the first time, indicates that a 6867C/G SNP of the PD-1 gene is associated with lupus nephropathy in Caucasian SLE patients.

Adolescent↗
PubMed2004

Autoantibodies and self-reported health complaints in relatives of systemic lupus erythematosus patients: a community based approach.

First-degree relatives (FDRs) and spouses to a population-derived cohort of lupus patients were investigated for the occurrence of selected autoantibodies and self-reported health complaints. A healthy reference population was included. The lupus population consisted of 103 index cases. A total of 275/375 available relatives accepted to enter the study. Two hundred and twenty-six/315 (72%) were FDRs and 49/60 (82%) were spouses. Serum was analysed for ANA using indirect immunofluorescence on Hep-2 cells at the following dilutions: 1:40, 1:80 and 1:160 and in addition sera were tested for anti-dsDNA, IgM RF, ACA (IgM, IgG), anti-beta2GPI (IgM, IgG) and antibodies to prothrombin. ANA positivity occurred more frequently in FDRs compared with spouses and controls at serum dilution 1:160 (10 versus 0% and 2.5%, respectively, P = 0.04 and P < 0.01), 1:80 (24 versus 4% and 5%, respectively, P = 0.003 and P < 0.001) and 1:40 (31 versus 10% and 10%, respectively, P = 0.006 and P < 0.0001). ANA positivity in FDRs occurred randomly, irrespective of family relationship. Fifty-three/184 versus 2/32 FDRs to patients with definite SLE (D-SLE) and incomplete SLE (I-SLE), respectively, tested ANA positive at 1:80 (P < 0.05). FDRs with ANA titer at 80 were affiliated to lupus probands with high SLICC scores (P < 0.05). Self-reported health complaints, cardiovascular/thromboembolic events in particular, were more frequent among FDRs than in spouses. The population-based approach adopted in the present study supports previous clinic-based evidence of an increased propensity for autoantibody occurrence in relatives to SLE patients. In FDRs, present ANA positivity was associated with increased prevalence of health complaints and ANA positivity in FDRs was related to the criterial burden and cumulated damage in corresponding lupus probands. The low ANA frequency among spouses of SLE patients argues against a significant autoantibody triggering effect of shared environment in adult life.

Adult↗
PubMed2003

Allelic variation of the inducible costimulator (ICOS) gene: detection of polymorphisms, analysis of the promoter region, and extended haplotype estimation.

The human chromosome region 2q33 including the three costimulatory molecules CD28, CTLA-4 and ICOS, has been subject to much attention due to its linkage to a number of autoimmune diseases. The search for the causal relationship of this linkage has revealed several polymorphisms, but no variations in the amino acid sequences, except for one polymorphism in the leader sequence of CTLA-4. In the present study, we examined the ICOS gene of an unrelated group of healthy donors from the Danish population. We were able to report 16 intronic SNP, one intronic G-insert and two repeat regions in intron 4, consistent with the [T]n and the [GT]n regions reported in a Japanese study. Putative haplotypes for the established SNP and repeat polymorphisms have been estimated by computational analysis. Sequencing of approximately 3500 bp of the upstream region of ICOS revealed an additional eight SNP of which two resided in putative NF-kB and Sp1 sites. In accordance with previous studies we detected no variations in the coding regions except for a rare polymorphism that was found in one donor in the last codon of exon 5, which lead to a heterozygous genotype, but no amino acid change. This suggests that regulation of transcription rather than protein structure could be a possible mechanism in the explanation of linkage.

5' Flanking Region↗
PubMed2003

Association of a putative regulatory polymorphism in the PD-1 gene with susceptibility to type 1 diabetes.

The immunoreceptor programmed cell death-1 (PD-1) is reported to play an important role in the regulation of peripheral tolerance in rodents, and it was recently shown that a polymorphism in a regulatory site of the PD-1 gene is associated with susceptibility to the autoimmune disease systemic lupus erythematosus (SLE) in humans. We investigated the existence of single-nucleotide polymorphisms (SNPs) in the PD-1 gene in patients with type 1 diabetes in comparison with healthy control subjects, by analyzing 94 children and adolescents with type 1 diabetes diagnosed before their eighteenth birthday (male : female = 52 : 42) and 155 control subjects. Polymorphisms in the complete PD-1 gene (minus the large intron 1) were detected by sequencing. In total, we identified 14 SNPs, of which six have been previously described, including an intronic 7146G/A SNP. We found this polymorphism to be associated with the development of type 1 diabetes [found in 12.2% of diabetic individuals vs 6.8% in controls; odds ratio (OR) = 1.92]. The associated allele is previously shown to alter a transcription factor-binding site (RUNX1/AML1), and the results of this study suggest that this allele could act as an additional susceptibility allele to type 1 diabetes.

Adolescent↗
PubMed2001

Leukocyte-depletion of blood components does not significantly reduce the risk of infectious complications. Results of a double-blinded, randomized study.

Allogeneic blood transfusions are claimed to be an independent risk factor for postoperative infections in open colorectal surgery due to immunomodulation. Leukocyte-depletion of erythrocyte suspensions has been shown in some open randomized studies to reduce the rate of postoperative infection to levels observed in nontransfused patients. Using a double-blinded, randomized design, we studied the postoperative infection rate in patients undergoing open colorectal surgery transfused with either leukocyte-depleted erythrocyte suspensions (LD-SAGM) or non-leukocyte-depleted erythrocyte suspensions (SAGM). Unselected patients (n 279) were allocated to receive LD-SAGM (n 139) or SAGM (n 140) if transfusion was indicated. Forty-five percent were transfused, yielding 48 patients in the LD-SAGM group and 64 in the SAGM group. Thirteen patients were excluded because they received one type of transfusion in spite of randomization to the other type. No significant differences in the rates of postoperative infections (P=0.5250) or postoperative complications (P=0.1779) were seen between the two transfused groups. Infection rates were 45% and 38% in the transfused groups and 21% and 23% in the nontransfused groups. No significant difference between the transfused groups was seen on any single infectious event, mortality rate, or duration of hospitalization. Leukocyte-depletion of erythrocyte suspensions transfused to patients undergoing open colorectal surgery does not reduce postoperative infection rates.

Aged↗
PubMed1995

Three-colour flow cytometric immunophenotyping in HIV-patients; comparison to dual-colour protocols.

Flow cytometric measurement of circulating CD4+ lymphocytes is important in the evaluation of disease progression in HIV-infected patients. Development of dyes that can be exited at 488 nm and have emission maximum in the far red area has made three-colour protocols, together with fluorescein isothiocyanate (FITC) and R-phycoerythrin (PE), possible in most clinical flow cytometers. We report here the comparison of a two-tube, three-colour protocol (including CD45/CD4/ CD3 and CD8/CD4/CD3) with our conventional dual-colour protocol. No significant differences were found between percentage of CD3+ lymphocytic cells determined with three different antibody combinations. When the CD8/CD4/CD3 combination was used a systematic overestimation of CD3+ CD4+% cells was found. This turned out to be caused by the formation of 'CD8-escapees'. These are clumps of CD8+ cells that fall outside the lymphocyte gating region, principally because of high side scatter. The problem can be overcome by rigorous vortexing to loosen aggregates. The lymphocyte gating principle used in this protocol (gating on a side scatter/CD45 dot plot) is readily applicable to other antibody combinations. This was demonstrated by measuring CD5+ B lymphocytes, a subset receiving increasing attention in the study of HIV-induced immune deviations. We conclude that our three-colour protocol for CD4+ T-lymphocyte determinations offers significant advantages to the conventional dual-colour method, and we suggest that when possible anti-CD45 be added to dual-colour combinations in order to improve lymphocyte gating.

Antigens, CD↗
PubMed1994

Stimulation of intercellular adhesion molecule-1 (ICAM-1) antigen expression and shedding by interferon-gamma and phorbol ester in human renal carcinoma cell cultures: relation to peripheral blood mononuclear cell adhesion.

In the present study we investigated the effect of interferon-gamma (IFN-gamma) and phorbol-12-myristate 13 acetate (PMA) on intercellular adhesion molecule-1 (ICAM-1) antigen expression and shedding in human renal carcinoma cell cultures. We also examined the functional consequences of ICAM-1 antigen expression and soluble ICAM-1 molecules on the adhesion of peripheral blood mononuclear cells (PBMC). Incubation of the human renal carcinoma cell line CaKi-1 with IFN-gamma or PMA enhanced ICAM-1 antigen expression. The calcium ionophore, 4-bromo-calcium ionophore A23187 (Bromo-A23187) significantly enhanced the IFN-gamma and PMA effect. Soluble ICAM-1 (sICAM-1) was detected in the supernatants of stimulated but not unstimulated cultures, and correlated significantly with cellular expression. Using 51Cr-labelled peripheral blood mononuclear cells in a cell adhesion assay, we demonstrated increased adhesion in IFN-gamma-treated CaKi-1 cultures, which was augmented by Bromo-A23187. This adhesion was blocked by preincubation of CaKi-1 cells with monoclonal antibody against ICAM-1 or by preincubation of PBMC with either monoclonal antibody against leucocyte function associated antigen-1 alpha (LFA-1 alpha), a major receptor for ICAM-1, supernatants from treated cultures or purified sICAM-1 molecules. Thus, shedding of ICAM-1 may play a role during the escape from immunosurveillance by renal carcinoma cells.

Antigens, Neoplasm↗
PubMed1994

Interferon-gamma increases cellular calcium ion concentration and inositol 1,4,5-trisphosphate formation in human renal carcinoma cells: relation to ICAM-1 antigen expression.

In the present study, we investigated the effect of interferon-gamma (IFN-gamma) on cellular calcium ion concentration [Ca2+]i and inositol 1,4,5-trisphosphate (Ins 1,4,5-P3) formation in the human renal carcinoma cell line CaKi-1. We also examined the possible role of a Ca(2+)-dependent mechanism during IFN-gamma-induced intercellular adhesion molecule 1 (ICAM-1) antigen expression. IFN-gamma caused a rapid concentration-dependent rise in [Ca2+]i, which was partly inhibited by diltiazem, a calcium channel blocker, TMB-8, an inhibitor of intracellular calcium redistribution, and in calcium-free medium. IFN-gamma caused a fourfold increase in Ins 1,4,5-P3 formation. The induction of ICAM-1 antigen expression was synergistically enhanced by 4-bromocalcium ionophore A23187. Finally, the calcium antagonists diltiazem. TMB-8 and EGTA, as well as two potent inhibitors of Ca(2+)-dependent kinases, calmidazolium (R24571) and W7, had no or only a minor inhibitory effect on IFN-gamma induction. Our data suggest that IFN-gamma increases [Ca2+]i in CaKi-1 cells by stimulating influx of Ca2+ and release of Ca2+ from intracellular stores, probably via Ins 1,4,5-P3 formation. IFN-gamma signal transduction in our model may not be limited to an increase in [Ca2+]i and Ins 1,4,5-P3, since IFN-gamma-induced ICAM-1 antigen expression was abrogated to a minor degree by calcium antagonists and not coupled to Ins 1,4,5-P3 formation.

Antigens↗
PubMed1994

Effect of radiographic contrast media on granulocyte phagocytosis of Escherichia coli in a whole blood flow cytometric assay.

RATIONALE AND OBJECTIVES: Earlier studies have demonstrated an adverse effect of radiographic contrast media (CM) on granulocyte phagocytosis. Most studies in the past have depended on granulocyte separative procedures that may themselves affect granulocyte functions. This study was performed to evaluate the effect of CM on phagocytosis using a flow cytometric assay allowing more physiological assay conditions. METHODS: Twenty consecutive patients were blindly randomized to receive the nonionic ratio 3.0 CM iohexol or the ionic ratio 3.0 CM ioxaglate for intravenous urography. Granulocyte phagocytic potential was measured before and at 1, 5, and 20 minutes after CM administration with a flow cytometric whole blood method evaluating the ingestion of complement- and immunoglobulin G (IgG)-opsonized fluorescent Escherichia Coli bacteria. RESULTS: The ability of granulocytes to phagocytize opsonized E. Coli was adversely affected by both CM used. Compared with baseline values, significantly decreased phagocytic activity was observed for iohexol at 1, 5, and 20 minutes and for ioxaglate at 1 and 5 minutes. The largest decrease with ioxaglate was from 85.3 +/- 10.5 to 69.3 +/- 16.3 (5 minutes), and the largest change with iohexol was from 87.1 +/- 8.5 to 74.5 +/- 15.9 (5 minutes). CONCLUSION: These results confirm earlier reports that ionic and nonionic CM adversely affect the phagocytic ability of granulocytes after intravenous administration.

Escherichia coli↗
PubMed1994

Redistribution of granulocytes during adrenaline infusion and following administration of cortisol in healthy volunteers.

Major surgical procedures induce an endocrine metabolic stress response characterized by increased secretion of adrenaline and cortisol. Furthermore, surgical stress is accompanied by granulocytosis in peripheral blood. The granulocytosis may be due to increased adrenaline and cortisol secretion. The purpose of this study was to investigate the redistribution of granulocytes during adrenaline infusion and following administration of cortisol. Granulocytes were isolated from peripheral blood from eight healthy volunteers, labelled with indium-111-tropolene and reinjected. The distribution of granulocytes was imaged by using a gamma camera and calculated with an interfaced computer three times during a control period and three times during a corresponding hour af adrenaline infusion 0.05 micrograms kg b.w.-1 min-1. The distribution was then measured every second h for another 6-h control period and then for 6 h following administration of cortisol 3.6 mg kg b.w.-1. Infusion of adrenaline resulted in granulocytosis in peripheral blood and a reduction of radioactivity of the spleen to 83.0% of the initial value. The effect of adrenaline on the bone marrow was negligible. Cortisol administration was followed by granulocytosis and decreased radioactivity of both the spleen (81.5%) and the bone marrow (79.8%). It is concluded that the spleen is an active immunological organ as both adrenaline and cortisol induces efflux of granulocytes from the spleen. The cortisol induced efflux of granulocytes from the bone marrow explains that granulocytosis also occurs in splenectomized patients after major surgery.

Adult↗