The expression of cytokines and chemokines in the blood of patients with severe weight loss from anorexia nervosa: an exploratory study.

Anorexia nervosa (AN) is a serious, potentially life-threatening disorder characterized by severe weight loss, dysregulated eating, and often excessive exercise. While psychiatric illnesses such as depression are associated with increased levels of pro-inflammatory mediators, evidence for such disturbances in patients with AN has been less clear. In an exploratory study of possible disturbances in immune responses in AN, we assayed a panel of cytokines and chemokines in the blood of patients undergoing inpatient treatment, testing the hypothesis that metabolic disturbances in this disease would lead to a pattern of immune disturbances distinct from that of other psychiatric diseases. For this purpose, we evaluated patients by the Beck Depression Inventory-II (BDI-II) and the Eating Disorders Examination-Questionnaire and assessed cytokines and chemokines by enzyme-linked immunosorbent assays. Patients reported a moderate level of depression (mean BDI-II = 22.6) but exhibited few immunologic abnormalities of the kind associated with major depressive disorder [e.g., increased interleukin (IL)-6]; RANTES showed the most frequent elevations and was increased in 4 of the patients studied. Together, these findings suggest that features of AN such as loss of adipose tissue and excessive exercise may attenuate cytokine production and thus modulate the experience of illness that impacts on core features of disease.

Anti-apolipoprotein A-1 autoantibodies as biomarker for atherosclerosis burden in patients with periodontitis.

BACKGROUND AND OBJECTIVE: Anti-apolipoprotein A-1 (anti-apoA-1) IgG is a potential marker of atherosclerotic plaque vulnerability and cardiovascular complications. In patients with periodontitis the presence of anti-apoA-1 IgGs in serum and their association with atherosclerosis is unknown. MATERIAL AND METHODS: One-hundred and thirty subjects with periodontal disease and 46 healthy subjects, matched for age and gender, participated in this study. Anti-apoA-1 IgG, high-sensitivity C-reactive protein (hsCRP) and matrix metalloproteinase (MMP) -2, -3, -8 and -9 were measured in serum samples. An ankle-brachial index (ABI) value below 1.11 served as a surrogate marker of atherosclerosis. Predictive accuracies of biomarkers for abnormal ABI were determined using receiver-operating characteristics curves and logistic regression analyses. RESULTS: Compared with healthy controls, periodontitis patients showed lower median ABI values (1.10 vs. 1.15; p < 0.0001), a higher prevalence of anti-apoA-1 IgG positivity (23.8% vs. 6.5%; p = 0.009) and higher concentrations of hsCRP (1.62 mg/L vs. 0.85 mg/L; p = 0.02) and MMP-9 (435 µg/mL vs. 283 µg/mL; p < 0.0001). In patients younger than 50 years of age (n = 66), anti-apoA-1 IgG was found to be the best predictor for an abnormal ABI (area under the curve = 0.63; p = 0.03). Anti-apoA-1 IgG positivity increased the risk of having an abnormal ABI (odds ratio = 4.20; p = 0.04), independently of diabetes, smoking and body mass index. CONCLUSIONS: Anti-apoA-1 IgG positivity and atherosclerosis, as reflected by abnormal ABI, were more prevalent in periodontitis patients than in age- and gender-matched controls. In younger periodontitis patients, anti-apoA-1 IgG was found to be the best predictor of atherosclerosis burden.

Anti-apolipoprotein A-1 IgG in patients with myocardial infarction promotes inflammation through TLR2/CD14 complex.

OBJECTIVES: Toll-like receptor (TLR)-mediated vascular inflammation, inducible by - amongst other factors - auto-antibodies, is increasingly recognized as a potential mediator of cardiovascular disease. We investigated whether anti-apolipoprotein (Apo)A-1 IgG was associated with a pro-inflammatory cytokine profile in myocardial infarction (MI) patients and whether anti-ApoA-1 IgG elicited a pro-inflammatory response by activating TLRs. METHODS: As surrogate markers of atherosclerotic plaque vulnerability, interleukin (IL)-6, tumour necrosis factor (TNF)-α, matrix metalloproteinase (MMP)-9 and MMP-3 levels were assessed in 221 consecutive MI patients. Using human monocyte-derived macrophages (HMDMs) we investigated (i) the anti-ApoA-1 IgG interaction with TLRs using proximity ligation assay and (ii) anti-ApoA-1 IgG-dependent IL-6/TNF-α production. TLR involvement was further confirmed using HEK293-Blue TLR-2/-4 cells and by computational docking simulations. RESULTS: In MI patients, anti-ApoA-1 IgG positivity was associated with higher levels of IL-6, TNF-α and MMP-9, but lower MMP-3 levels. In in vitro experiments, anti-ApoA-1 antibodies bound to HDMDs in a TLR2-dependent manner, resulting in nuclear translocation of NFκB and a significant increase in TNF-α and IL-6 production. Subsequent functional studies highlighted the importance of CD14 as co-receptor in the anti-ApoA-1 IgG-TLR2-induced cytokine production. Additional bioinformatic studies identified structural homologies between TLR2 and ApoA-1, which may explain the observed cross-reactivity between antibodies against these two molecules. CONCLUSIONS: Anti-ApoA-1 IgG positivity in MI is associated with a high-risk cytokine profile. These auto-antibodies promote inflammation by stimulating the TLR2/CD14 receptor complex, probably because of molecular mimicry, which may contribute to atherosclerosis-related complications in patients.

[External quality controls for allergy analysis in the Quality Control Center Switzerland from 2006 to 2008]. / Les contrôles de qualité externes pour le laboratoire d'allergologie auprès du Centre suisse de contrôle de qualité de 2006 à 2008.

External assessment of analytical performance is part of the quality assurance in medical laboratory. These external controls are mandatory in Switzerland since 2006 for IgE analysis. The Swiss Society for Immunology and Allergy and the Swiss external quality centers had launched a program for total IgE, IgE specific for cat epithelium, birch pollen and peanut, and multi-specific IgE. They have set up criteria for proficiency assessment. Analysis of data obtained from 2006 to 2008 in the Quality Control Center Switzerland shows that results are very good for all the methods used and that a large number of participants fulfill the requirements to obtain the certificate of QUALAB conformity.

Tuberculosis screening in patients with psoriasis before antitumour necrosis factor therapy: comparison of an interferon-gamma release assay vs. tuberculin skin test.

BACKGROUND: Antitumour necrosis factor (anti-TNF) treatments may reactivate latent tuberculosis infection (LTBI). For detecting LTBI, the tuberculin skin test (TST) has low sensitivity and specificity. Interferon-gamma release assays (IGRA) have been shown to be more sensitive and specific than TST. OBJECTIVE: To compare the TST and the T-SPOT.TB IGRA for identifying LTBI in patients with psoriasis before anti-TNF treatment. METHODS: A retrospective study was carried out over a 4-year period on patients with psoriasis requiring anti-TNF treatment. All were subjected to the TST, T-SPOT.TB and chest X-ray. Risk factors for LTBI and history of bacillus Calmette-Guérin (BCG) vaccination were recorded. The association of T-SPOT.TB and TST results with risk factors for LTBI was tested through univariate logistic regression models. Agreement between tests was quantified using kappa statistics. Treatment for LTBI was started 1 month before anti-TNF therapy when indicated. RESULTS: Fifty patients were included; 90% had prior BCG vaccination. A positive T-SPOT.TB was strongly associated with a presumptive diagnosis of LTBI (odds ratio 7.43; 95% confidence interval 1.38-39.9), which was not the case for the TST. Agreement between the T-SPOT.TB and TST was poor, kappa = 0.33 (SD 0.13). LTBI was detected and treated in 20% of the patients. In 20% of the cases, LTBI was not retained in spite of a positive TST but a negative T-SPOT.TB. All patients received an anti-TNF agent for a median of 56 weeks (range 20-188); among patients with a positive TST/negative T-SPOT.TB, no tuberculosis was detected with a median follow-up of 64 weeks (44-188). One case of disseminated tuberculosis occurred after 28 weeks of adalimumab treatment in a patient with LTBI in spite of treatment with rifampicin. CONCLUSION: This study is the first to underline the frequency of LTBI in patients with psoriasis (20%), and to support the use of IGRA instead of the TST for its detection. Nevertheless, there is still a risk of tuberculosis under anti-TNF therapy, even if LTBI is correctly diagnosed and treated.

Quantitative scoring of an interferon-gamma assay for differentiating active from latent tuberculosis.

The aim of this study was to assess the contribution of an interferon-gamma release assay (T-SPOT.TB) to the differentiation of active tuberculosis (TB) from latent TB infection by quantifying spot-forming units (sfu). The investigation was a prospective study of contacts exposed to a case of contagious TB and cases of HIV-negative culture-proven TB referred over a 16-month period. Tuberculin skin tests (TSTs) and T-SPOT.TB were performed in 310 contacts 8-12 weeks after exposure. In subjects with culture-proven TB, T-SPOT.TB was performed within 2 weeks of initiation of treatment. The analysis included all contacts with a positive T-SPOT.TB result and all subjects with TB. TB contacts (n = 127) and cases (n = 58) were included. Mean+/-sd T-SPOT.TB results were 107+/-56 (range 1-207) sfu for TB, 54+/-60 (7-239) sfu for contacts with positive T-SPOT.TB results and a TST induration diameter of >5 mm, and 19+/-27 (7-143) sfu for contacts with positive T-SPOT.TB results and a TST induration diameter of < or =5 mm. By receiver operating characteristic curve analysis, a threshold value of 49.5 sfu showed a sensitivity of 83% and specificity of 74% for distinguishing latent TB infection from TB. Although T-SPOT.TB results were significantly related to disease activity, the test cannot be recommended for the diagnosis of tuberculosis.

Synovial tissue interleukin-18 expression and the response to treatment in patients with inflammatory arthritis.

OBJECTIVE: To measure synovial tissue interleukin-18 (IL-18) expression in patients with inflammatory arthritis, and to identify associations with serum levels, disease activity, and response to treatment. METHODS: Synovial tissue biopsies and serum samples were obtained from patients with early, active, rheumatoid arthritis (RA) (n = 12), undifferentiated seronegative arthritis (SnA) (n = 9), psoriatic arthritis (PsA) (n = 5), and reactive arthritis (ReA) (n = 2) before and one year after introduction of disease modifying antirheumatic drug (DMARD) treatment. Osteoarthritis (OA) tissues were compared. Tissue IL-18 expression was determined after immunohistochemical staining using a semiquantitative scale. Serum IL-18 was measured by enzyme linked immunosorbent assay. RESULTS: Before treatment was started, tissue IL-18 expression was increased in each diagnostic group compared with OA (p<0.05). Tissue IL-18 expression was correlated with serum C reactive protein levels (r = 0.53, p = 0.003) but not with serum IL-18. After DMARD treatment, 12 patients (five RA, four SnA, three PsA) were re-evaluated. Decreases in tissue IL-18 expression were observed in eight, although the trend did not reach significance (p = 0.068). Changes in tissue IL-18 expression were correlated with changes in serum IL-18 (r = 0.62, p = 0.041) and C reactive protein (r = 0.72, p = 0.009). CONCLUSIONS: Synovial tissue IL-18 expression was correlated with disease activity in inflammatory arthritis. After treatment, tissue levels changed in parallel with changes in serum IL-18 and with changes in the acute phase response. These observations support a role for IL-18 in the pathophysiology of inflammatory arthritis.

Serum interleukin 18 and interleukin 18 binding protein in rheumatoid arthritis.

OBJECTIVE: To measure serum interleukin 18 (IL18) and IL18 binding protein (IL18BP) levels in patients with inflammatory arthropathies, and to identify associations with disease status and the response to treatment. METHODS: Serum samples were obtained before and after methotrexate treatment from patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) attending an early arthritis clinic. IL18 and IL18BP were measured by enzyme linked immunosorbent assay (ELISA). RESULTS: Sixty patients with RA and 13 with PsA were evaluated. Serum IL18 levels were significantly higher in RA than in PsA (p<0.001). After six months' treatment with methotrexate, IL18 levels were reduced, but the differences were not significant (p=0.052). In cross sectional analyses, no correlations between IL18 levels and measures of disease activity or structural damage in RA were found. In longitudinal analyses, no correlations between IL18 levels and the response to treatment or the degree of progressive joint damage were found. Similarly, IL18BP levels were raised in RA, and were not associated with measures of the clinical status or the response to treatment. CONCLUSION: Raised serum levels of IL18 are consistent with a pathophysiological role in RA. However, in this study measurement of circulating IL18 and IL18BP did not correlate significantly with clinical measures of disease activity or the response to treatment in patients with early RA.

Apolipoprotein A-I inhibits the production of interleukin-1beta and tumor necrosis factor-alpha by blocking contact-mediated activation of monocytes by T lymphocytes.

Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), essential components in the pathogenesis of immunoinflammatory diseases, are strongly induced in monocytes by direct contact with stimulated T lymphocytes. This study demonstrates that adult human serum (HS) but not fetal calf or cord blood serum displays inhibitory activity toward the contact-mediated activation of monocytes by stimulated T cells, decreasing the production of both TNF-alpha and IL-1beta. Fractionation of HS and N-terminal microsequencing as well as electroelution of material subjected to preparative electrophoresis revealed that apolipoprotein A-I (apo A-I), a "negative" acute-phase protein, was the inhibitory factor. Functional assays and flow cytometry analyses show that high-density lipoprotein (HDL)-associated apo A-I inhibits contact-mediated activation of monocytes by binding to stimulated T cells, thus inhibiting TNF-alpha and IL-1beta production at both protein and messenger RNA levels. Furthermore, apo A-I inhibits monocyte inflammatory functions in peripheral blood mononuclear cells activated by either specific antigens or lectins without affecting cell proliferation. These results demonstrate a new anti-inflammatory activity of HDL-associated apo A-I that might have modulating functions in nonseptic conditions. Therefore, because HDL has been shown to bind and neutralize lipopolysaccharide, HDL appears to play an important part in modulating both acute and chronic inflammation. The novel anti-inflammatory function of apo A-I reported here might lead to new therapeutic approaches in inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, systemic lupus erythematosus, and atherosclerosis.

Benefit of prestorage leukocyte depletion of single-donor platelet concentrates.

BACKGROUND AND OBJECTIVES: The presence of contaminating white blood cells (WBCs) in platelet concentrates is associated with transfusion reactions and may adversely alter the quality of platelets during storage. Leukocyte depletion by filtration of platelets has been increasingly used to avoid these complications. However, the best time for filtration and the benefits of filtering single-donor platelet concentrates (thrombapheresis, TH) have yet to be clearly defined. METHODS: In a randomized study of 202 TH collected with an Autopheresis C system, we determined whether prestorage filtration (preSF) of WBCs from TH as compared with poststorage (bedside) filtration (postSF) resulted in a better product. Levels of cytokines and C3a accumulating in the medium during storage, platelet activation state, in vivo platelet recovery, and transfusion reactions were compared in pre- and poststorage products. RESULTS: As compared to preSF, significantly more postSF TH had detectable levels of tumor necrosis factor-alpha (TNF-alpha; 47 vs. 15%; p<0.0001) and interleukin 6 (13 vs. 3%; p = 0.02), lower pH (p<0.0001) and decreased levels of C3a (910 vs. 2,000 pg/ml; p<0. 0001). Furthermore, platelet activation was increased in postSF TH (p = 0.022). PostSF TH tended to plug the bedside filter (27% of postSF TH delivered) from day 3 onward. There was also a significant difference in platelet recovery, postSF TH showing a lower corrected count increment (CCI; p = 0.0055) when taking into account the postSF TH that plugged filters (CCI = 0), but no difference when plugged TH were excluded. A correlation could be established between TNF-alpha levels and poor in vivo recovery (p<0.0001). Febrile nonhemolytic transfusion reactions were low in both groups (4 and 9%). CONCLUSION: These results indicate a benefit of preSF TH as compared with postSF TH based on the following parameters: decrease in cytokine levels, less platelet activation, maintenance of higher pH, and more efficient use of stored platelets (27% of postSF TH were lost because of plugging of filters). These results apply particularly to the Autopheresis C systems with its high initial WBC content.

Inflammation: "a natural experiment" for the systemic pathogenicity of cytokines.

It has previously been demonstrated that the overproduction of interleukin-6 (IL-6) is a key element in the clinical and biological abnormalities encountered in Castleman's disease (CD). The particular case of a male child with a localized form of CD is reported. In this patient, evidence was found of a correlation between systemic manifestations and circulating IL-6, and IL-6 gene overexpression in the germinal centers of hyperplastic lymph nodes. Circulating IL-6 levels were 10- to 100-fold higher than in all CD cases previously documented. This unique biological feature was closely associated with high levels of circulating IL-1 and tumor necrosis factor-alpha (TNF-alpha), which are known for their ability to induce and/or amplify IL-6 production. One month after surgical removal of the pathological lymph node, the clinical and biological abnormalities diminished, while circulating IL-6 levels dropped dramatically eight months later. It is worth noting that after resection, the time-course of the IL-6 decrease closely correlated with that of IL-1 and TNF-alpha. Considering that in various inflammatory diseases IL-1, TNF-alpha and IL-6 may act in a synergistic manner in inducing systemic manifestations, this case report raises new questions as to the nature of the systemic pathogenicity of cytokines in CD.

Concentrations and origins of soluble interleukin 6 receptor-alpha in serum and synovial fluid.

OBJECTIVE: To determine levels of soluble interleukin 6 receptor-alpha (sIL-6R alpha) in synovial fluid (SF) and serum from patients with different rheumatic diseases, and to analyze its cellular origin compared to IL-6. METHODS: IL-6 and sIL-6R alpha concentrations were measured in sera, SF, and culture supernatants of different cells types using specific sandwich ELISA. RESULTS: IL-6 levels were significantly higher (30 to 1000-fold) in SF than in sera, and higher in inflammatory arthropathies such as rheumatoid arthritis (RA), chondrocalcinosis, and gout than in osteoarthritis (OA). sIL-6R alpha levels in SF from patients with RA, gout, and chondrocalcinosis were also higher (24.7 +/- 7.5, 23.2 +/- 9.1, and 19.5 +/- 7.4 ng/ml, respectively) than in patients with OA (10.1 +/- 5 ng/ml), although the difference was distinctly smaller. In contrast, sIL-6R alpha concentrations did not differ significantly between the sera of healthy donors and patients. sIL-6R alpha levels were similar in SF and sera from inflammatory arthropathies, but lower in all osteoarthritic SF, compared to their corresponding serum. In contrast to IL-6, sIL-6R alpha was produced in high amounts by hepatocytes but not by structural cells of the joint (chondrocytes, synoviocytes, fibroblasts, and endothelial cells). Polymorphonuclear cells and mononuclear cells released intermediate levels. A significant correlation between sIL-6R alpha concentration and total number of leukocytes was observed in SF. CONCLUSION: Elevated levels of sIL-6R alpha were found in serum, likely to result from a marked release by hepatocytes in vitro. That levels are higher in inflammatory SF may be due in part to release by inflammatory cells in situ.

Levels of cytokine inhibitors: a possible marker of disease activity in childhood dermatomyositis and polymyositis.

The levels of cytokines and of their inhibitors were assessed by ELISA in serum samples from 3 children with dermatomyositis (DM) and polymyositis (PM) who were followed for several years. We observed normal levels of IL-6 and TNF alpha, but increased concentrations of IL-1Ra and TNF-sR75 at disease onset, which was followed by a decrease in the levels of IL-1Ra and TNF-sR75 in the patients with a favorable disease outcome. In contrast, in the one patient who relapsed no correlation with the levels of cytokines or of their inhibitors could be established. These results suggest that cytokine inhibitors such as IL-1Ra and TNF-sR may be useful additional parameters for monitoring the evolution of DM and PM.

Circulating levels of tumor necrosis factor soluble receptors in systemic lupus erythematosus are significantly higher than in other rheumatic diseases and correlate with disease activity.

OBJECTIVE: To investigate the difference in acute phase protein responses between patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and spondyloarthropathies (SpA). METHODS: Circulating levels of cytokines inducing the production of acute phase proteins such as interleukin (IL)-6, IL-1 beta, and tumor necrosis factor (TNF)-alpha, and of cytokine inhibitors such as TNF soluble receptors (TNF-sR55 and TNF-sR75) and IL-1 receptor antagonist (IL-1ra), were measured in 2 cohorts of patients. The first cohort included 52 patients with SLE and 22 with RA, and the second included 21 with SLE, 20 with RA, and 18 with SpA. An examination at the time of blood collection and the Systemic Lupus Activity Measure (SLAM) index were used to assess disease activity in patients with SLE. Serum levels of IL-6 were measured using a biological assay, and concentrations of IL-1 beta, TNF-alpha, TNF-sR55, TNF-sR75, and IL-1ra were assessed by immunoassays. RESULTS: Although C-reactive protein (CRP) levels were significantly lower in SLE than in RA or SpA, the concentrations of circulating IL-6 or TNF-alpha were higher in SLE. The most striking observation was that TNF-sR levels were significantly higher in SLE than in RA or SpA. The TNF-alpha: TNF-sR ratio was also significantly lower in SLE than in RA. TNF-sR55 and TNF-sR75 levels correlated with disease activity in SLE. CONCLUSION: The weak acute phase protein response in SLE may be explained by a decreased ratio between inducing cytokines and their inhibitors. In addition, TNF-sR may prove a useful biological marker for the followup of SLE, where acute phase protein response is generally low during disease exacerbations.

Low levels of interleukin-1 receptor antagonist coincide with kidney involvement in systemic lupus erythematosus.

The objective was to study the relationship between the levels of interleukin-1 receptor antagonist (IL-1Ra) and disease activity and the acute-phase response in SLE patients with and without renal involvement. Twenty SLE patients who had distinct active clinical manifestations (eight glomerulonephritis, four systemic vasculitis without kidney involvement, nine skin rash, 12 arthritis, five serositis, four neuropsychiatric manifestations, three thrombocytopenia, one myositis and one haemolytic anaemia) were studied during a period of 8-12 months. Serum and plasma samples were taken at intervals of 6 weeks-4 months and tested for IL-1Ra, IL-1 beta, IL-6, IgG and anti-dsDNA, Clq, C3, C4 and C-reactive protein (CRP). IL-1Ra serum concentrations were increased in most SLE patients with active disease when compared to normal blood donors. However, at the time of flare, significantly higher levels of IL-1Ra were observed in patients with extra-renal disease as compared to other patients (median [range]: 363 [202-3041] and 4847 [268-27180] pg/ml for patients with and without renal involvement, respectively). This difference was not due to proteinuria. IL-1Ra levels did not correlate with SLEDAI score during flares, but they were elevated during flares in patients with extra-renal manifestations. When disease activity was at its highest, IL-1Ra concentrations correlated with IL-1 beta (r = 0.76; P < 0.001), IL-6 (r = 0.60; P < 0.01) and CRP (r = 0.61; P < 0.01), but not with C1q, C3, C4 and anti-dsDNA levels. The study showed that the pattern of inflammatory cytokines in active SLE varies in a manner that is dependent on which organs are involved. A relative absence of IL-1Ra response appears to be a feature characteristic of kidney involvement. IL-1Ra elevation clearly correlates with flares involving other organs.

Plasma concentrations of cytokines, their soluble receptors, and antioxidant vitamins can predict the development of multiple organ failure in patients at risk.

OBJECTIVES: The aims of this study were: a) to evaluate plasma concentrations of cytokines and their soluble receptors, as well as antioxidant substances in patients at high risk of developing multiple organ failure; b) to investigate early change: and c) to examine the possible prognostic value of these elements. DESIGN: Prospective analysis. SETTING: Surgical intensive care unit (ICU) of a university hospital. PATIENTS: sixteen patients at risk for multiple organ failure. MEASUREMENTS AND MAIN RESULTS: Ten patients developed multiple organ failure and five of them died. Whereas tumor necrosis factor-alpha (TNF-alpha) plasma concentrations were only borderline higher in patients developing multiple organ failure, TNF-soluble receptors 55 and 75 were significantly increased during all ICU days compared with patients not going into organ failure. Interleukin-6 plasma concentrations were higher in patients developing multiple organ failure during the first 2 days after ICU admission. The antioxidant vitamin C was significantly decreased in patients going into multiple organ failure during all ICU days. Other biochemical markers of antioxidant activity, such as vitamin E, copper, and zinc plasma concentrations, did not differ between the two groups. CONCLUSIONS: Our data suggest that there is a marked increase in anti-TNF activity and a decrease of antioxidant defense in patients at risk of developing multiple organ failure. The predictive value of plasma concentrations of circulating TNF-soluble receptors and vitamin C in this type of patient needs further evaluation.

Dynamics of fever and the cytokine network in systemic juvenile arthritis.

AIM OF THE STUDY: To determine the levels of the inflammatory cytokines IL1 alpha, IL1 beta, TNF alpha, IL6, IL8 and of their inhibitors TNF-sR55, TNF-s R75 and IL1-Ra during temperature elevation in systemic juvenile chronic arthritis. METHODS: Fifty-six serum samples were collected at regular intervals from seven children during 8 fever cycles. Cytokine levels were determined using enzyme-linked immunoassays. RESULTS: Levels of IL1 alpha, IL1 beta, TNF alpha and IL8 showed no variations. In contrast, IL6 and IL1-Ra levels paralleled the fever spikes. TNF-sR75 levels were also correlated with the fever. CONCLUSION: Fever dynamics in systemic juvenile chronic arthritis may be partly related to cytokine variations.

Dysregulation of the in vivo production of interleukin-1 receptor antagonist in patients with rheumatoid arthritis. Pathogenetic implications.

OBJECTIVE: Patients with rheumatoid arthritis (RA) have defective hypothalamic responses to inflammation, possibly because of excessive production of cytokine inhibitor, which could blunt the effects of cytokines on the hypothalamus, or because of an imbalance between interleukin-1 beta (IL-1 beta) and interleukin-1 receptor antagonist (IL-1Ra), which could create a mainly proinflammatory state. The present study was undertaken to investigate these possibilities. METHODS: The in vivo kinetics of IL-1 beta and IL-1Ra secretion were studied in patients with RA, osteoarthritis (OA), and chronic osteomyelitis (OM), and in normal controls before and after surgery. RESULTS: The 24-hour levels of IL-1Ra were significantly increased in RA (P < 0.001), but there was no diurnal variation in any group. Preoperative levels of IL-1Ra were higher in RA and OA sera (P = 0.001). After surgery, IL-1Ra behaved like an acute-phase reactant protein in all subjects. IL-1 beta was 10-20 times higher in RA than in OM and OA patients at baseline, but the percentage increase in all groups postoperatively was the same. RA patients had an IL-1Ra:IL-1 beta ratio of 26.2 +/- 3.7 (mean +/- SEM) at baseline (OM patients 89.2 +/- 5.8 and OA patients 1,310 +/- 363); this increased to 66.5 +/- 19.8 after surgery (OM patients 120 +/- 6.7 and OA patients 325.8 +/- 106). CONCLUSION: RA patients have a dysregulation of IL-1Ra production, and it seems unlikely that the defective hypothalamic response seen in RA is due to a functional deficit of IL-1 beta.