PubMed Health⌕ Search

Biomedical subjects

Klaus Bendtzen

Publications and source records attributed to Klaus Bendtzen.

At least 19 recordsLinked to original sources
PubMed2006

[Rituximab (MabThera) as treatment of active rheumatoid arthritis].

Rituximab (RTX) is a murine/human monoclonal antibody to CD20, a protein expressed almost exclusively on human B-lymphocytes. RTX induces rapid and marked B-cell depletion with beneficial clinical effects in 1/3 to 1/2 of rheumatoid arthritis patients. Treatment is given as two iv. infusions with a two-week interval and in combination with methotrexate. Mild to moderate side-effects are frequent, particularly during the first infusion, but long-term side-effects are generally rare, although pulmonary events and reactivation of viral infections of the liver is of concern.

Antibodies, Monoclonal↗
PubMed2006

Increased plasma levels of IL-6 in bacteremic periodontis patients after scaling.

Bacteremia frequently occurs after dental treatment. Periodontal inflammation may influence the incidence, magnitude and duration of bacteremia. The presence of circulating oral bacteria or bacterial components may induce cytokine synthesis in blood cells, which may contribute to the development or exacerbation of atherosclerosis. The present study tested the hypothesis that bacteremia occurring after scaling in periodontitis patients results in altered plasma levels of cytokines. Twenty periodontitis patients were subjected to scaling. Blood samples at baseline and at 0.5, 10 and 30 minutes postscaling were examined for bacteremia whereas baseline and eight-hour postscaling blood samples were examined for the levels of IL-1beta, TNF-alpha, IL-6, IL-8, IL-10 and IL-12p70. IL-6 levels were significantly increased eight hours after scaling, while IL-8 was significantly decreased. No systematic changes occurred in the levels of IL-1beta, TNF-alpha, IL-10 and IL-2p70. IL-6 levels may be increased while IL-8 may be decreased due to scaling, which may have implications for general health.

Adult↗
PubMed2006

Self-reactive CD4+ T cells and B cells in the blood in health and autoimmune disease: increased frequency of thyroglobulin-reactive cells in Graves' disease.

The mechanisms underlying activation of potentially self-reactive circulating B cells and T cells remain unclear. We measured the uptake of a self-antigen, thyroglobulin, by antigen presenting cells, and the subsequent proliferation of CD4(+) T cells and B cells from healthy controls and patients with autoimmune thyroiditis. In Hashimoto's thyroiditis, B cells bound increased amounts of thyroglobulin in a complement- and autoantibody-dependent manner, and the thyroglobulin-elicited proliferation of CD4(+) T cells and B cells was complement dependent. Increased proportions of Tg-responsive CD4(+) T cells and B cells were found in patients with Graves' disease. Notably, both patient groups and healthy controls exhibited higher proliferative responses to thyroglobulin than to a foreign recall antigen, tetanus toxoid. Our results suggest that self-tolerance can be broken by exposure of circulating lymphocytes to high local concentrations of self-antigen, and that complement plays a role in the maintenance of autoimmune processes, at least in Hashimoto's thyroiditis.

Autoantibodies↗
PubMed2006

Individualized monitoring of drug bioavailability and immunogenicity in rheumatoid arthritis patients treated with the tumor necrosis factor alpha inhibitor infliximab.

OBJECTIVE: Infliximab, an anti-tumor necrosis factor alpha (anti-TNFalpha) antibody, is effective in the treatment of several immunoinflammatory diseases. However, many patients experience primary or secondary response failure, suggesting that individualization of treatment regimens may be beneficial. This study was undertaken to investigate whether serologic monitoring of infliximab bioavailability and immunogenicity in individual patients would be useful in optimizing treatment regimens to improve efficacy and tolerability. METHODS: To avoid the use of solid-phase assays, two radioimmunoassays were developed: one for measurement of levels of anti-infliximab antibody, and a functional one for measurement of TNFalpha binding due to infliximab. Sera from 106 randomly selected rheumatoid arthritis patients were tested within 6 months of therapy initiation, and associations between findings of serum assays and disease activity, infusion reactions, and treatment failure occurring within 18 months were assessed. RESULTS: Trough serum infliximab levels after the first 2 intravenous infusions of infliximab at 3 mg/kg varied considerably between patients (range 0-22 microg/ml). At this stage, only 13% of the patients were anti-infliximab antibody positive. With subsequent infusions, the frequency of antibody positivity rose to 30% and 44% (at 3 months and 6 months, respectively), accompanied by diminished trough levels of infliximab. Indeed, low infliximab levels at 1.5 months predicted antibody development and later treatment failure. There were highly significant correlations between high levels of antibodies and later dose increases, side effects, and cessation of therapy. High baseline disease activity, judged by C-reactive protein level and Disease Activity Score, was associated with low levels of infliximab at the early stage of treatment and later development of anti-infliximab antibodies. Cotreatment with methotrexate resulted in slightly reduced antibody levels after 6 months; other disease-modifying antirheumatic drugs and prednisolone had no effect. CONCLUSION: Development of anti-infliximab antibodies, heralded by low preinfusion serum infliximab levels, is associated with increased risk of infusion reaction and treatment failure. Early monitoring may help optimize dosing regimens for individual patients, diminish side effects, and prevent prolonged use of inadequate infliximab therapy.

Antibodies, Monoclonal↗
PubMed2006

Spironolactone induces apoptosis and inhibits NF-kappaB independent of the mineralocorticoid receptor.

Spironolactone (SPIR) binds to cytoplasmic mineralocorticoid receptors (MR) and functions as an aldosterone (ALDO) antagonist. Recently, however, the drug was shown to have an early MR independent, suppressive effect on immunoactive and inflammatory cytokines as well as an apoptotic effect on blood mononuclear cells (MNC). To elucidate the mechanism behind SPIR's apoptotic effect, we investigated the relation between apoptosis and cytokine suppression for SPIR along with the apoptosis-inducing and antiinflammatory drug sulfasalazine (SFZ). Using human MNC, we found that SPIR and SFZ, at concentrations 10 and 1000 muM, respectively, significantly increased both apoptosis and cell death. Production of inflammatory cytokines was significantly reduced by 3 to 30 muM SPIR and by 300 to 1000 muM SFZ. We also found that 0.4 muM SPIR and 300 muM SFZ significantly reduced the activity of NF-kappaB, a transcription factor involved in both apoptosis and immunoinflammation. ALDO, the MR antagonist, eplerenone, and the SPIR metabolite, 7alpha-thiomethyl-spironolactone, slightly reduced NF-kappaB activity, but they did not interfere with SPIR's effect, showing that MR binding is not involved in SPIR-induced suppression of NF-kappaB activity. Finally, phosphorylation of IkappaBalpha was also significantly reduced by SPIR. These results provide new insight into the apoptotic and anti-inflammatory effects of SPIR.

Apoptosis↗
PubMed2006

Effects of spironolactone on human blood mononuclear cells: mineralocorticoid receptor independent effects on gene expression and late apoptosis induction.

1 Spironolactone (SPIR) binds to cytoplasmic mineralocorticoid receptors (MR) and functions as an aldosterone antagonist. Recently, the drug was shown to have an early suppressive effect on several immunoactive and proinflammatory cytokines. 2 To elucidate the mechanism behind this, the four MR-binding steroids SPIR, canrenone, 7alpha-thiomethyl-spironolactone and aldosterone (ALDO) were investigated for effects on lipopolysaccharide- and phytohemagglutinin-A-activated human blood mononuclear cells. Gene expression was examined after 4 h using microarrays, and SPIR affected 1018 transcripts of the (=) 22,000 probed. In contrast, the SPIR-related steroids affected 17 or fewer transcripts. Combining SPIR and ALDO resulted in 940 affected transcripts, indicating that SPIR has an early gene-regulatory effect independent of MR. 3 The affected genes encode a large number of signalling proteins and receptors, including immunoinflammatory response genes and apoptosis and antiapoptosis genes. Apoptosis was evident in CD3-, CD14- and CD19-positive cells, but only after 18 h of exposure to SPIR. 4 The transcriptional network involving the differentially regulated genes was examined and the results indicate that SPIR affects genes controlled by the transcription factors NF-kappaB, CEBPbeta and MYC. 5 These observations provide new insight into the non-MR-mediated effects of SPIR.

Adult↗
PubMed2006

Persistence of neutralizing antibodies after discontinuation of IFNbeta therapy in patients with relapsing-remitting multiple sclerosis.

OBJECTIVE: The main objective was to follow serum levels of neutralizing antibodies (NABs) against interferon-beta (IFNbeta) after discontinuation of IFNbeta therapy. BACKGROUND: A large proportion of patients treated with recombinant IFNbeta for multiple sclerosis (MS) develop therapy-induced NABs. Knowledge of persistence of NABs after discontinuation of therapy is limited. DESIGN/PATIENTS: A retrospective follow-up study of patients treated in Denmark for relapsing remitting (RR) MS with IFNbeta for at least 12 months. NAB-positive patients, who discontinued therapy, were followed up with measurements of NABs. METHODS: We measured NAB-neutralizing capacity and NAB titres a.m. Kawade using a clinically validated cytopathic effect assay. RESULTS: Thirty-seven patients were included. Mean follow-up time was 22 months. Of the 29 patients with a NAB titre at or above 25 prior to termination of therapy, only three patients reverted to a titre below 25. Of these, two had a titre below 200 and one patient a titre of 600 at the last examination before treatment stop. The longest post-treatment follow-up during which a patient maintained NAB positivity was 59 months. CONCLUSION: NABs against IFNbeta, especially with high titres, tend to persist for a long time after discontinuation of IFNbeta therapy. NABs should always be measured before reinstitution of IFNbeta treatment in NAB-positive patients.

Adjuvants, Immunologic↗
PubMed2006

Periodontal and hematological characteristics associated with aggressive periodontitis, juvenile idiopathic arthritis, and rheumatoid arthritis.

BACKGROUND: Periodontitis shares several clinical and pathogenic characteristics with chronic arthritis, and there is some degree of coexistence. The aims of this study were to elucidate whether patients with localized aggressive periodontitis (LAgP), generalized aggressive periodontitis (GAgP), juvenile idiopathic arthritis (JIA), and rheumatoid arthritis (RA) share periodontal and hematological characteristics distinguishing them from individuals free of diseases. METHODS: The study population consisted of white adults ( or=4 mm, CAL>or=2 mm, and ABL>or=2 mm compared to controls. The percentage of sites with CAL>or=2 mm significantly correlated with the levels of IgM-RF and IgA-RF. Missing teeth in JIA and RA patients were not lost due to periodontitis. Patients with GAgP showed higher levels of leukocytes, including neutrophils, and CRP compared to controls. In part, JIA and RA patients showed similar results. CONCLUSIONS: Young adults with RA may develop periodontal destruction, and these patients require professional attention. Both differences and similarities in periodontal and hematological variables were seen in individuals with periodontitis, JIA, and RA.

Adult↗
PubMed2005

Cytokines and soluble tumour necrosis factor I receptor levels during pretransplant conditioning in allogeneic stem-cell transplantation.

The inflammatory response induced by the conditioning regime may be related to the outcome in allogeneic stem-cell transplantation (SCT). However, previous statements concerning the prognostic significance of cytokine measurements during conditioning have not been conclusive. We investigated a broad range of cytokines in plasma samples drawn daily immediately before start of pretransplant conditioning and during the conditioning. The presented data indicate that single-day measurements of inflammatory cytokines during conditioning may lead to unreliable conclusions concerning their prognostic significance. However, serial quantitation of soluble tumour necrosis factor receptor I (sTNFRI) is more likely to reflect the degree of inflammatory activation induced by pretransplant conditioning.

Adult↗
PubMed2005

Plasma TNF binding capacity in patients with juvenile idiopathic arthritis.

INTRODUCTION: Tumour necrosis factor (TNF)-alpha and TNF-beta, also called lymphotoxin (LT), are bound by soluble truncated TNF receptors (sTNFRI and II) that are released from cell surfaces and act as natural inhibitors of TNF-induced inflammation. We investigated the plasma levels of sTNFRI and II in parallel with LT binding capacity (LTBC) in 44 patients with juvenile chronic arthritis (JIA). METHODS: LTBC was determined by spiking diluted plasma samples with 1000 pg/ml of human recombinant LT. Detectable LT was measured by an in-house ELISA and LTBC was expressed in arbitrary units (AU) as the percentage value of bound LT to added LT. The levels of sTNFRI and-II were measured by ELISA (R&D). RESULTS: We found slightly reduced sTNFRI and II levels in JIA patients (n=44) compared with healthy controls sTNFRI: 1118 pg/ml (656-2074) [mean (range)] vs. 1262 pg/ml (819-2280) p=0.015; sTNFRII: 1953 pg/ml (889-4476) vs. 2311 pg/ml (1309-4186) p=0.008. The sTNFRI levels correlated positively with morning stiffness (r=0.30, p=0.044), physician's global assessment (r=0.39; p=0.009) and CRP (r=0.43; p=0.0048). sTNFRII did not correlate with measures of disease activity. In contrast, patient LTBC values were elevated compared to controls: 44 AU (36-52) vs. 31 AU (13-41) [mean (range)], p<0.0001, but did not correlate with disease activity. CONCLUSION: Despite overall slightly reduced plasma levels of sTNFRI and II, the capacity to bind TNF appeared to be increased in plasma samples from JIA patients.

Adolescent↗
PubMed2005

Cytokine profiles in peripheral blood and whole blood cell cultures associated with aggressive periodontitis, juvenile idiopathic arthritis, and rheumatoid arthritis.

BACKGROUND: Cytokines play a key role in the pathogenesis of inflammatory diseases. An obvious question is whether patients with aggressive periodontitis, juvenile idiopathic arthritis, or rheumatoid arthritis share blood cytokine profiles distinguishing them from individuals free of disease. METHODS: The study population consisted of Danish white adults, <35 years of age, diagnosed with localized aggressive periodontitis (LAgP; N = 18), generalized aggressive periodontitis (GAgP; N = 27), juvenile idiopathic arthritis (JIA; N = 10), or rheumatoid arthritis (RA; N = 23) and healthy individuals with no systemic or oral diseases (control [CTRL]; N = 25). Enzyme-linked immunosorbent assays were used to determine the levels of interleukin (IL)-1alpha, IL-1beta, IL-1 receptor antagonist (IL-1Ra), IL-6, IL-10, tumor necrosis factor (TNF)-alpha, and lymphotoxin (LT)-alpha in peripheral blood (plasma) and unstimulated and stimulated whole blood cell cultures from the same blood collection. Autoantibodies (aAb) to IL-1alpha and IL-6 were quantitated by radioimmunoassay. RESULTS: Similar patterns of slightly higher IL-10 levels in plasma were found for GAgP and RA patients and in unstimulated cultures for GAgP, RA, and JIA patients. Interestingly, unstimulated cultures also demonstrated similar patterns of higher TNF-alpha levels for these three groups of patients. Similar group patterns of periodontitis patients (LAgP and GAgP) included increased IL-1Ra levels in stimulated cultures, which also showed similar group patterns of arthritis patients (JIA and RA) with respect to higher IL-1alpha and lower LT-alpha levels. Low titers of aAb to IL-1alpha and IL-6 were found in almost all individuals. CONCLUSION: Patients with aggressive periodontitis and types of arthritis presented with similar components of blood cytokine profiles distinguishing them from individuals free of disease.

Adolescent↗
PubMed2004

Serum cardiac troponin I in acute stroke is related to serum cortisol and TNF-alpha.

BACKGROUND: Serum cardiac troponin I (cTnI) is a specific marker of myocardial injury related to in-patient fatality and cardiac injury in acute stroke. We investigated whether cTnI in acute stroke is related to serum cortisol, acute inflammatory response, and insular damage. We also investigated whether cTnI predicted outcome at 3 months. PATIENTS AND METHODS: The study was based on 155 patients with CT-confirmed acute cerebral infarction and study inclusion within 24 h (50% within 12 h) of stroke onset. Blood samples were obtained on inclusion. Stroke severity was assessed by the Scandinavian Stroke Scale (SSS) and outcome was assessed by the modified Rankin Scale (mRS), death or dependency was defined as mRS > or =3 three months after stroke. RESULTS: 35% of all patients and 63% of patients who died within 3 months were troponin positive. Tumor necrosis factor-alpha (TNF-alpha) and cortisol were independently related to detection of cTnI: TNF-alpha(+100 pg/ml) OR 1.5 (CI 95% 1.1-2.2), cortisol(+100 nmol/l) OR 1.1 (CI 95% 1.01-1.2). SSS and age were also included in this model and did not reach significance. cTnI positivity was, together with age, stroke severity and prestroke mRS, but not s-cortisol, an independent explanatory variable of outcome at 3 months (death or dependency) with OR 4.1 (CI 95% 1.1-14.5). cTnI did not relate to insular involvement. CONCLUSION: In this study, cortisol and TNF-alpha were independently related to cTnI, which was predictive of 3-month prognosis.

Aged↗
PubMed2004

Blood cell gene expression profiling in rheumatoid arthritis. Discriminative genes and effect of rheumatoid factor.

UNLABELLED: To study the pathogenic importance of the rheumatoid factor (RF) in rheumatoid arthritis (RA) and to identify genes differentially expressed in patients and healthy individuals, total RNA was isolated from peripheral blood mononuclear cells (PBMC) from eight RF-positive and six RF-negative RA patients, and seven healthy controls. Gene expression of about 10,000 genes were examined using oligonucleotide-based DNA chip microarrays. The analyses showed no significant differences in PBMC expression patterns from RF-positive and RF-negative patients. However, comparisons of gene expression patterns from all fourteen RA patients and healthy controls identified a subset of discriminative genes. These results were validated by real time reverse transcription polymerase chain reaction (RT-PCR) on another group of RA patients and healthy controls. This confirmed that the following genes had a significantly higher expression in RA patients than in healthy controls: CD14 antigen, defensin alpha-1 and alpha-3 (DEFA), fatty-acid-Coenzyme A ligase, long-chain 2 (FACL), ribonuclease 2 (RNASE2), S100 calcium-binding protein A8 and A12 (S100A8 and S100A12). In contrast, the expression of MHC class II, DQ beta1 (HLA-DQB1) was significantly reduced in RA patients compared to healthy controls. CONCLUSIONS: With the analytical procedure employed, we did not find any indication that RF-positive and RF-negative RA are two fundamentally different diseases. Most of the genes discriminative between RA patients and healthy individuals are known to be involved in immunoinflammatory responses, especially those related to altered phagocytic functions.

Adult↗
PubMed2004

Spironolactone inhibits production of proinflammatory cytokines by human mononuclear cells.

BACKGROUND: The mineralocorticoid receptor antagonist spironolactone (SPIR) reduces the mortality and morbidity in patients with congestive heart failure (CHF). Overexpression of proinflammatory cytokines contribute to the development and progression of CHF. MATERIAL AND METHODS: We examined the effect of SPIR on in vitro cytokine production by human peripheral blood mononuclear cells (PBMC). PBMC were cultured with 10-1000 microM SPIR and stimulated with lipopolysaccharide or phytohaemagglutinin-P. Tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, IL-1beta, and interferon (IFN)-gamma were measured in culture supernatants by enzyme-linked immunosorbent assay and mRNA expression of the cytokines was determined by real-time reverse transcriptase polymerase chain reaction (PCR). RESULTS: SPIR inhibited the stimulated production of TNF-alpha, IL-6, and IFN-gamma, whereas the release of IL-1beta was not significantly affected. The SPIR-induced cytokine inhibition occurred at the transcriptional level and was independent of antimineralocorticoid and antiandrogen activities. CONCLUSION: The findings suggest that inhibited production of proinflammatory cytokines may be an extrarenal mechanism that contributes to the beneficial effect of SPIR in patients with CHF.

Aldosterone↗