Sotrastaurin and everolimus pharmacokinetics after single-dose coadministration.

INTRODUCTION: Sotrastaurin is an immunosuppressant that blocks T-lymphocyte activation via protein kinase C inhibition. The authors determined whether a pharmacokinetic interaction occurs between sotrastaurin and everolimus, both of which are substrates and inhibitors of CYP3A4. METHODS: This was a randomized, three-period, crossover study in 18 healthy subjects. They received single oral doses of (1) 100 mg sotrastaurin, (2) 2 mg everolimus, and (3) the drug combination. Clinical and pharmacokinetic data were collected to Day 5 after each treatment. RESULTS: Coadministration of everolimus decreased sotrastaurin C(max) from 638 +/- 295 to 539 +/- 211 ng/ml yielding a combination/ monotherapy ratio (90% confidence interval) of 0.87 (0.76 - 1.00). Sotrastaurin total AUC was not altered by everolimus with values of 3660 +/- 1853 versus 3630 +/- 2006 ng*h/ml and a ratio of 1.00 (0.88 - 1.13). Sotrastaurin increased everolimus C(max) from 15 +/- 6 to 16 +/- 6 ng/ml yielding a ratio of 1.15 (0.99 - 1.33) and increased everolimus total AUC from 114 +/- 50 to 137 +/- 56 ng*h/ml yielding a ratio of 1.20 (1.05 - 1.37). The possibility that a higher dose of sotrastaurin than used in this study might further increase everolimus blood levels cannot be excluded. CONCLUSIONS: Coadministration of a single 100 mg dose sotrastaurin with a single 2 mg dose everolimus did not alter sotrastaurin pharmacokinetics to a clinically relevant extent. Everolimus AUC was increased 20% by sotrastaurin.

Lumiracoxib does not affect the ex vivo antiplatelet aggregation activity of low-dose aspirin in healthy subjects.

This randomized, double-blind, placebo-controlled study evaluated the pharmacodynamic effects of concomitant low-dose aspirin and lumiracoxib in healthy subjects. Participants received lumiracoxib 400 mg once daily (n = 14) or placebo (n = 14) for 11 days, with concomitant low-dose aspirin (75 mg once daily) from days 5 to 11. Ex vivo pharmacodynamic assessments included assays of platelet aggregation and urinary thromboxane and prostacyclin metabolite profile. Arachidonic acid-stimulated platelet aggregation was reduced from 76.3% on day 4 to 4.8% on day 11 in the placebo group and from 75.8% on day 4 to 5.1% on day 11 in the lumiracoxib group. Collagen-induced platelet aggregation was reduced from 77.5% on day 4 to 52.8% on day 11 in the placebo group and from 79.5% on day 4 to 55.9% on day 11 in the lumiracoxib group. Urinary thromboxane and prostacyclin were unaffected by lumiracoxib. In conclusion, concomitant lumiracoxib did not interfere with the cyclooxygenase-1-mediated antiplatelet effects of low-dose aspirin.

No influence of moderate hepatic impairment on the pharmacokinetics of lumiracoxib, an oral COX-2 selective inhibitor.

The aim of this study was to evaluate the influence of hepatic impairment on the pharmacokinetics (PK) of the novel cyclooxygenase-2 (COX-2) selective inhibitor lumiracoxib (Prexige), so that dose recommendations for clinical use can be provided. This was an open-label, single dose, case-controlled study in which eight subjects with liver cirrhosis classed as moderate hepatic impairment (Child-Pugh score: 7-9) and eight demographically-matched healthy subjects received a single oral 400 mg dose of lumiracoxib. Routine safety assessments were made and blood samples were taken for determination of lumiracoxib concentrations for 96 h post dose. The ex vivo binding of lumiracoxib to plasma proteins was determined pre dose and at 2 and 12 h post dose. An analysis of variance was used to detect differences in PK parameters (AUC, Cmax and Tmax) between the treatment groups. There were no significant differences between subjects with moderate hepatic insufficiency and healthy subjects in the area under the lumiracoxib plasma concentration-time curves (AUC(0-infinity)): 29.2 +/- 6.7 microg h ml(-1) versus 28.7 +/- 6.3 mircrog h ml(-1). The rate of absorption of lumiracoxib was not significantly altered by hepatic impairment based on Cmax and Tmax. The protein-bound fraction of lumiracoxib exceeded 98% both in healthy control subjects and in those with moderate hepatic insufficiency. A single dose of 400 mg lumiracoxib was well tolerated. In conclusion, no dose adjustments appear to be required when lumiracoxib is administered to patients with either mild or moderate hepatic impairment.

Gastroduodenal tolerability of lumiracoxib vs placebo and naproxen: a pilot endoscopic study in healthy male subjects.

BACKGROUND: Lumiracoxib (Prexige) is a cyclooxygenase-2 (COX-2) selective inhibitor. AIM: To compare the gastroduodenal tolerability of lumiracoxib with placebo and naproxen in a randomized, parallel-group, double-blind study. METHODS: : Sixty-five healthy male subjects were randomized to receive 8 days' dosing with lumiracoxib 200 mg twice daily (b.d.) (n = 21), placebo (n = 22) or naproxen 500 mg b.d. (n = 22). Endoscopic evaluations of gastric and duodenal mucosae were conducted at baseline and after 8 days' dosing. Serum was assayed for ex-vivo concentrations of thromboxane B2 (TxB2) to determine cyclooxygenase-1 (COX-1) inhibitory activity. RESULTS: Sixty subjects (20 per group) completed the study. No gastroduodenal erosions were observed in subjects receiving lumiracoxib. Thirteen subjects receiving naproxen developed duodenal erosions. At the gastric site, one subject in each of the naproxen and placebo groups had erosions; one subject receiving naproxen also developed a small asymptomatic gastric ulcer. Gastrointestinal adverse events accounted for 42.3% of all adverse events, occurring in 3/21, 4/22 and 6/22 of the lumiracoxib, placebo and naproxen groups, respectively. TxB2 levels were similar for patients receiving placebo or lumiracoxib, but were reduced by > 95% in patients receiving naproxen, compared with placebo. CONCLUSIONS: Multiple doses of lumiracoxib resulted in gastroduodenal tolerability similar to placebo and superior to naproxen.

Influence of hepatic impairment on everolimus pharmacokinetics: implications for dose adjustment.

OBJECTIVE: We assessed the influence of hepatic impairment on the pharmacokinetics of the immunosuppressant everolimus to provide dose recommendations for clinical use. METHODS: In this open-label, single-dose, case-control study, 8 subjects with liver cirrhosis classed as moderate hepatic impairment (Child-Pugh score, 7-9) and 8 demographically matched healthy control subjects received a single oral 2-mg dose of everolimus. Routine safety assessments were made, and blood samples were taken for determination of everolimus concentrations and protein binding. RESULTS: The apparent clearance of everolimus was significantly reduced by 53% in subjects with moderate hepatic impairment compared with healthy subjects (9.1 +/- 3.1 versus 19.4 +/- 5.8 L/h). This was manifested by a 115% higher area under the blood concentration-time curve (AUC) (245 +/- 91 versus 114 +/- 45 ng. h/ml) and 84% prolonged half-life (79 +/- 42 versus 43 +/- 18 hours) in subjects with hepatic impairment. The rate of absorption of everolimus was not altered by hepatic impairment on the basis of the maximum blood concentration (C(max)) and time to reach C(max) (t(max)). Protein binding was similar in the two groups (73.8% +/- 3.6% versus 73.5% +/- 2.4%). A significant positive correlation of the everolimus AUC with bilirubin level (r = 0.86) and a significant negative correlation with albumin concentration (r = 0.72) was observed. CONCLUSIONS: The dose of everolimus should initially be reduced by half in patients with mild and moderate hepatic impairment on the basis of the Child-Pugh classification. Therapeutic monitoring would be a helpful adjunct to subsequent titration of everolimus exposure in this subpopulation. Everolimus has not been assessed in patients with severe hepatic impairment.

Population pharmacokinetics of everolimus in de novo renal transplant patients: impact of ethnicity and comedications.

BACKGROUND: Everolimus is a macrolide immunosuppressant intended for acute rejection prophylaxis after kidney transplantation. METHODS: A total of 5260 blood samples were collected in the context of two randomized, double-blind, multicenter efficacy trials in 673 patients over a 6-month period after kidney transplantation. The data were evaluated in a nonlinear mixed-effects model. The influence of demographic characteristics (age, weight, sex, and ethnicity) and of comedications on everolimus exposure was explored. RESULTS: For a reference 44-year-old, 71-kg Caucasian kidney allograft recipient receiving everolimus as part of a cyclosporine (INN, ciclosporin)-prednisone immunosuppressive regimen, the absorption rate constant was 6.07 h(-1) (standard error [SE], 0.70 h(-1)), the apparent clearance was 8.8 L/h (SE, 0.2 L/h), and the apparent central distribution volume was 110 L (SE, 5 L). There were no clinically relevant influences of age, weight, or sex on clearance. No significant difference in clearance was detected for Asian patients, whereas black patients had an average clearance that was 20% higher than that of nonblack patients. Patients concomitantly receiving erythromycin or azithromycin had an average 19% lower clearance. One patient receiving itraconazole had a 74% reduction in clearance. After we accounted for covariates, the remaining interindividual variability in clearance was 27% and the variability for distribution volume was 36%. The combined intraindividual and assay/measurement residual error in everolimus blood concentrations was 31%. CONCLUSIONS: Dose adjustment of everolimus on the basis of weight does not appear necessary. Black patients may need a higher dose to achieve exposure that is similar to that of nonblack patients. Concomitant administration of potent inhibitors of the cytochrome P450 isozyme CYP3A may reduce everolimus clearance and increase its blood concentrations.

Longitudinal assessment of everolimus in de novo renal transplant recipients over the first post-transplant year: pharmacokinetics, exposure-response relationships, and influence on cyclosporine.

OBJECTIVE: Our objective was to characterize the steady-state pharmacokinetics of everolimus and cyclosporine (INN, ciclosporin) when coadministered in de novo kidney allograft recipients during the first year after transplantation. METHOD: This study was a multicenter randomized double-blind study of 101 patients who were randomly assigned 1:1:1 to receive everolimus tablets at doses of 0.5 mg, 1 mg, or 2 mg twice daily with cyclosporine and prednisone. Blood sampling for the pharmacokinetics of everolimus and cyclosporine was performed on day 1, on weeks 1, 2, 3, and 4, and on months 2, 3, 6, 9, and 12. Everolimus dose-proportionality and stability over time were assessed in the context of linear regression and ANOVA models. Everolimus exposure-response relationships between area under the blood concentration-time curve (AUC) and changes in platelets, leukocytes, and lipids were explored with the median-effect model. Potential differences in cyclosporine dosing and pharmacokinetics at different levels of everolimus exposure were assessed in the context of ANOVA. RESULTS: Everolimus steady state was reached on or before day 7, with a median 3-fold accumulation of drug exposure compared with that after the first postoperative dose. Both steady-state maximum concentration and AUC were dose proportional over the full dose range when assessed on day 1, as well as for the full duration of the study at steady state. There was evidence for longitudinal stability in AUC of everolimus during the course of the study. The interindividual pharmacokinetic variability for AUC was 85.4% and intraindividual, interoccasion variability was 40.8%. Age (range, 17-69 years), weight (range, 49-106 kg), and sex (65 men and 36 women) were not significant contributors to variability. There was an increasing incidence of transient thrombocytopenia (< or =100 x 10(9)/L) with increasing everolimus AUC (P = .03). Cyclosporine doses, trough concentrations, and AUC exhibited similar temporal patterns during the course of the study regardless of the co-administered everolimus dose level (P = .13, .82, and .76, respectively). CONCLUSIONS: Everolimus exhibited dose-proportional, stable exposure during the first post-transplant year. For a 4-fold range of everolimus doses there were no differential effects on cyclosporine dosing or pharmacokinetics.

Neoepitope immunoassay: an assay for human interleukin 1 beta based on an antibody induced conformational change.

A secondary monoclonal antibody (mAb2) was generated by immunization with immune complexes of human IL-1 beta and a primary monoclonal (mAb1). mAb2 bound to a neoepitope on the IL-1 beta/mAb1-complex with a dissociation constant (Kd) of 26 pM but not to uncomplexed IL-1 beta. As assessed by the binding of labeled IL-1 beta and neutralization of bioactivity, mAb2 enhanced the affinity of IL-1 beta to mAb1; Kd-values were 108 pM in absence and 5.4 pM in presence of mAb2. By analyzing a series of mutants of IL-1 where surface loops had been exchanged with the corresponding loops of human IL-1 receptor antagonist protein, a critical region responsible for mAb2 binding was localized to the C-terminal region. In addition to mAb1/IL-1 beta-complexes, mAb2 bound pro-IL-1 beta/mAb1 complexes as well as pro-IL-1 beta suggesting that mAb2 recognized a conformation of IL-1 beta resembling that of pro-IL-1 beta. Using this pair of mAbs, chemiluminescent and enzyme linked assays with detection limits of 2 pg/ml hIL-1 beta have been established.

Interleukin 1 (IL-1) receptor antagonist, soluble tumor necrosis factor receptors, IL-1 beta, and IL-8--markers of remission in rheumatoid arthritis during treatment with methotrexate.

OBJECTIVE: To examine circulating levels of cytokines and cytokine inhibitors and their production by blood mononuclear cells (MNC) in patients with active rheumatoid arthritis (RA) before treatment with methotrexate (MTX) and inactive disease upon treatment as well as healthy control individuals. METHODS: Interleukin-1 receptor antagonist (IL-1ra), soluble tumor necrosis factor receptors p55 and p75 (sTNFr; p55 and p75), interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha), interleukin-8 (IL-8), and monocyte chemoattractant protein 1 (MCP-1) were assessed by immunoassays in sera and MNC culture supernatants of 27 patients with RA with active disease before and 14 patients with inactive disease during MTX treatment, and 10 healthy controls. RESULTS: Levels of circulating IL-1ra, sTNFr p55 and p75 were higher in patients with active RA compared to those with inactive disease or controls. At the cellular level, resting MNC of patients with active RA released more IL-1 beta and IL-8, but less IL-1ra, and showed a lower ratio of IL-1ra:IL-1 beta than MNC of patients without inflammatory symptoms or healthy controls. In addition, unstimulated and in vitro lipopolysaccharide stimulated MNC cultures of patients with inactive RA released higher amounts of sTNFr p75 than MNC of patients with active RA. CONCLUSION: Circulating levels of IL-1ra and sTNFr as well as IL-1 beta, IL-8, and sTNFr p75 release from MNC and the ratio of IL-1ra:IL-1 beta production by these cells serve as markers to assess complete disease remission in patients with RA during MTX treatment.

Methotrexate action in rheumatoid arthritis: stimulation of cytokine inhibitor and inhibition of chemokine production by peripheral blood mononuclear cells.

This open label study examines whether methotrexate (MTX) treatment modulates ex vivo synthesis of interleukin-1 receptor antagonist (IL-1ra), soluble tumour necrosis factor receptors (sTNFR p55 and p75), interleukin-1 beta (IL-1 beta), tumour necrosis factor alpha (TNF-alpha), interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) by peripheral blood mononuclear cells (PBMC) and whether changes reflect clinical response. Significant stimulation of IL-1ra and sTNFR p75 as well as inhibition of IL-8 production of PBMC were associated with clinical improvement observed in patients treated with MTX. When defining the characteristics of patients at study entry retrospectively in responders and non-responders, a significantly lower ratio of IL-1ra:IL-1 beta production before and its increase upon treatment was associated with clinical response in 13 patients compared to five patients not responding to MTX. In addition, clinical improvement was associated with decreased synthesis of IL-1 beta, TNF-alpha and IL-8 induced by bacterial lipopolysaccharide, IL-1 alpha and IL-1 beta in PBMC in vitro. These findings suggest that MTX therapy reverses the inflammatory type of rheumatoid arthritis (RA) blood mononuclear cells by stimulating cytokine inhibitor production while inhibiting inflammatory cytokine release at the same time. This may explain the powerful anti-inflammatory properties of low-dose MTX as observed in most RA patients. Pretreatment determination of the IL-1ra:IL-1 beta ratio in PBMC may be predictive with regard to a favourable therapeutic response and therefore may be useful for the selection of RA patients to be treated with MTX.

CGP 47969A: effect on collagen induced arthritis in DBA/1 mice.

OBJECTIVE: CGP 47969A is a novel and potent inhibitor of cytokine biosynthesis in human and murine monocytic cells. The effect of CGP 47969A on collagen induced arthritis (CIA) in DBA/1 mice was investigated and compared to that of prednisolone. METHODS: CIA was induced by intradermal injection of type II collagen in CFA at Day 0. CGP 47969A was applied orally, 5 times/week, starting at Day 15 after immunization. Arthritic signs were recorded 3 times/week for clinical scoring and radiographic analysis was performed at the end of the experiment at Day 60. Serum amyloid P (SAP) and anticollagen antibody titers were determined by ELISA at Day 60. RESULTS: CGP 47969A dose dependently reduced the incidence of arthritis from 93% in the positive control group to 60, 40, 30 and 10% at doses of 1, 5, 25 and 60 mg/kg/day, respectively. At a dose of 120 mg/kg, CGP 47969A totally prevented the occurrence of arthritis (ED50 between 1 and 5 mg/kg). Prednisolone at 3 and 30 mg/kg reduced the arthritis incidence to 70 and 30%, respectively. CGP 47969A dose dependently inhibited the joint destruction, as measured by radiographic scoring and its potency was comparable to that of prednisolone. The elevated serum levels of the positive acute phase protein SAP in arthritic animals were completely normalized by CGP 47969A at a dose of 60 mg/kg, however, neither CGP 47969A nor prednisolone influenced the plasma levels of anticollagen antibodies (IgG). CONCLUSION: Our results demonstrate that CGP 47969A is highly effective in CIA with a potency comparable to that of prednisolone. These promising results justify the expectation that this novel antiarthritic compound now under development might also be effective in the treatment of rheumatoid arthritis in man.

Monoclonal antibody based enzyme-linked and chemiluminescent assays for the human interleukin-1 receptor antagonist. Application to measure hIL-1ra levels in monocyte cultures and synovial fluids.

Interleukin-1 receptor antagonist (IL-1ra) has the potential to counteract at least part of the biological effects of interleukin-1. The outcome of an inflammatory reaction may therefore be determined by the balance between IL-1 and IL-1ra, rather than by IL-1 alone. We have developed an immunoassay to address this issue as well as to assess the effects of anti-inflammatory agents on the expression of IL-1 and IL-1ra in vitro or in body fluids. Recombinant human IL-1ra was expressed in an E. coli system, purified to homogeneity, and used to derive monoclonal antibodies in mice as well as polyclonal antibodies in rabbits. A sandwich ELISA was constructed with F(ab')2 fragments of a high affinity monoclonal antibody and the rabbit serum as a source of secondary antibody. The assay required no sample treatment to avoid interference by rheumatoid factor. The measuring range was 0.020-2 ng/ml. By labelling a second monoclonal antibody with an acridinium ester, a chemiluminescence assay with a wider measuring range (0.050-15 ng/ml) was generated. In accord with published data, we found that IL-1ra was secreted by human monocytes stimulated with LPS, Zymosan, IL-1 alpha, or human IgG. After an induction phase of ca. 4 hours and depending on the stimulus, IL-1ra accumulated linearly for periods up to 96 h. IL-1ra levels in synovial fluids of 19 patients suffering from various inflammatory joint diseases were compared with the cytokine levels of IL-1 beta, IL-6, IL-8, and TNF-alpha. Highest positive correlations were found with IL-8 and IL-1 beta. In normal blood donors IL-1ra serum levels were 150-800 pg/ml (Median: 387 pg/ml). Owing to its sensitivity and large measuring range the newly developed assays appear to be suitable for measuring IL-1ra in cell cultures as well as in biological fluids.

Interferon-gamma overcomes the glucocorticoid-mediated and the interleukin-4-mediated inhibition of interleukin-1 beta synthesis in human monocytes.

Interleukin-1 (IL-1) has been implicated in the tissue destruction of rheumatoid arthritis, a disease that is widely treated with glucocorticoids. In this study we investigated the effect of the T cell product interferon-gamma (IFN-gamma) on the glucocorticoid-mediated and on the IL-4-mediated inhibition of IL-1 beta mRNA and IL-1 beta protein synthesis in highly purified human monocytes. Both dexamethasone and IL-4 dose-dependently inhibited IL-1 beta mRNA and IL-1 beta protein synthesis after stimulation with LPS (300 ng/ml); maximal inhibition of 80-90% was achieved. IFN-gamma (1-100 U/ml) did not influence IL-1 beta mRNA and IL-1 beta protein levels in unstimulated cells, but potentiated the LPS-induced synthesis of IL-1 beta mRNA and IL-1 beta protein. After a preincubation time of 1 h, 100 U/ml of IFN-gamma increased the LPS-induced IL-1 beta production by about 20-40%. When human monocytes were preincubated for 1 h with IFN-gamma (100 U/ml) prior to the addition of dexamethasone (10(-6) M) and prior to the stimulation with LPS, the dexamethasone-mediated inhibition of IL-1 beta mRNA and IL-1 beta protein synthesis was totally neutralized by IFN-gamma. In addition, IFN-gamma totally overcame the negative effect of IL-4 (100 pM) on IL-1 beta protein synthesis. A preincubation period of at least 1 h with IFN-gamma was necessary for the neutralization of the dexamethasone effect. If IFN-gamma was given at the same time or after dexamethasone, only a weak effect was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Neutralization of interleukin-1 beta activity in vivo with a monoclonal antibody alleviates collagen-induced arthritis in DBA/1 mice and prevents the associated acute-phase response.

Interleukin-1 (IL-1) has been implicated in the development and progression of a variety of acute and chronic inflammatory diseases. Due to its pro-inflammatory and tissue-degrading activities, IL-1 is regarded as a major mediator of chronic inflammatory joint diseases, including rheumatoid arthritis in man, adjuvant arthritis in rats and collagen-induced arthritis in mice. However, conclusive experimental evidence for the crucial role of IL-1 in the development of joint destruction has not been presented as yet. In the present study, we investigated the effect of a neutralizing monoclonal mouse antibody against mouse IL-1 beta (IgG1 isotype) on the development and progression of collagen-induced arthritis in DBA/1 mice. The antibody was injected intraperitoneally 3 times a week, either from day 3 or from day 21 after primary immunization, to day 60. In the positive control group an arthritis incidence of 80% was observed after 60 days. The injection of a control antibody of the same isotype did not influence the incidence of arthritis, whereas injection of anti-IL-1 beta from day 21 reduced the arthritis incidence to about 30%. Injection of anti-IL-1 beta starting at day 3 totally prevented both the development of arthritis and the associated increase of the acute phase protein serum amyloid P (SAP). Anti-collagen antibody titers, which increased significantly after immunization, were not influenced by the injection of anti-IL-1 beta antibodies, in spite of the suppressive effect on arthritis development.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics and immunomodulatory effects on monocytes during prolonged therapy with liposomal muramyltripeptide.

The macrophage activator muramyl tripeptide-phosphatidyl ethanolamine (MTP-PE) was infused in liposomal form in 14 metastatic cancer patients (4 mg i.v. during 30 min twice weekly for 12 weeks). Clinical, pharmacokinetic and immunological parameters were studied before and 0.5, 2, 4, 24 and 72h after start of drug infusion in week 1, 4, 8 and 12. No tumor regressions were seen. Tumors progressed in 11 patients, in 4 of them within 2 months; 3 patients had stable disease. The intensity and frequency of side effects (fever and nausea) diminished from week 1 to 12. The rate of disappearance of total and free MTP-PE from blood was rapid and mean serum concentration-time curves remained unchanged throughout 12 study weeks. MTP-PE caused a marked increase of serum TNFa, IL-1 receptor antagonist (IL-1ra) and IL-6 in week 1, but not thereafter. In contrast, MTP-PE caused a persistent, 2-fold increase in serum neopterin and young forms of granulocytes (bands) during week 1 to 12. Before therapy, monocyte tumor cytotoxicity and in-vitro monocyte derived TNFa, IL-1 beta and IL-6 production were low in 9 patients (group L, < 15%) and high in 5 patients (group H, > 40%). Monocyte cytotoxicity and in-vitro cytokine production was transiently enhanced in week 1 in group L, it declined under therapy in group H. In conclusion, MTP-PE induced marked initial immunomodulation; the extent of the ex vivo monocyte cytokine and tumor cytotoxic response was dependent on pre-therapy cell activity. A decrease of the cytokine and IL-1ra response during prolonged therapy contrasted with a persistent increase of neopterin and juvenile blood granulocytes. The long lasting biologic effects may be relevant to direct future clinical studies with liposomal MTP-PE in an adjuvant setting.

The influence of major trauma on the regulatory levels of interleukin-1 (IL-1) and IL-2 in human mononuclear leukocytes.

The monokine Interleukin-1 (IL-1) and the lymphokine IL-2 are playing a crucial role within the course of an intact cell mediated immune response (CMI). It was the objective of this study to further elucidate the cytokine associate mechanisms of dysfunctional T-cell activation following major burn and mechanical trauma. Via comparative analysis of mRNA expression and protein release the major regulatory levels of IL-1 and IL-2 release under stressful conditions were to be determined in mitogen respectively LPS stimulated PBMC (peripheral blood mononuclear cells) cultures on consecutive days (D) 1, 3, 5, 7 and 10 post injury. Further, we wanted to scrutinize if inadequate IL-2 production post-trauma is possible due to a defective transduction of extracellular signals to the T-cell nucleus. In order to answer this question IL-2 mRNA expression and IL-2 protein releases were determined in PBMC cultures using the phosphokinase C (PKC) activator phorbol ester (PMA) as a costimulus together with PHA. When analyzing the cumulative data for IL-1 beta we saw until D 5 post-trauma a considerable impairment of the protein release in LPS stimulated PBMC cultures and recovery thereafter. In only a few individual PBMC cultures we saw a concurrence between the IL-1 beta mRNA signal intensity and the protein production. In the majority of the autoradiographies analyzed, the mRNA expression for IL-1 beta was considerably more distinct compared to controls while the corresponding protein release values were on control level or below. These results implicate that the suppression of IL-1 beta post-trauma is regulated mainly on a posttranscriptional level. Since Prostaglandin E2 (PGE2) has been found to have a vigorous impact on the IL-1 beta synthesis on the translational level, we assume that the high PGE2 levels post-trauma inhibit--via cAMP--sufficient IL-1 beta synthesis on the posttranscriptional level. IL-2 protein synthesis as well as mRNA expression in mitogen (PHA) stimulated PBMC cultures following trauma, was persistently and significantly depressed compared to controls during the time of observation. The addition of PMA as a costimulus to PHA, could induce very distinct mRNA signals for IL-2 with a signal intensity which was comparable to that found in the cells of healthy controls. Also the quantity of IL-2 protein release in the vast majority of all patients PBMC cultures following PHA/PMA induction was within the control range.(ABSTRACT TRUNCATED AT 400 WORDS)

Recombinant human C5a induces transcription but not translation of interleukin 1 beta mRNA in human monocytes.

The effect of recombinant human C5a (rhC5a) on the synthesis of interleukin 1 beta (IL-1 beta) was investigated in human monocytes, isolated by leukapheresis and countercurrent elutriation. rhC5a induced IL-1 beta mRNA synthesis in a dose- and time-dependent manner. Maximal induction was achieved at 3 h with rhC5a concentrations of 200 to 500 ng/ml. The maximal rhC5a-stimulated mRNA induction was about 75% of that observed using LPS as the stimulus (300 ng/ml). The inducing activity of rhC5a could be neutralized by preincubation with a polyclonal anti-C5a antibody. On the other hand rhC5a in optimal concentrations only weakly stimulated IL-1 beta protein synthesis, as measured by a two-site directed enzyme-linked immunoassay. When compared on Northern blots, a slightly reduced mobility of C5a-stimulated IL-1 beta mRNA was observed relative to LPS-stimulated RNA. To exclude the possibility that structural defects in the IL-1 beta mRNA are responsible for the weak translational efficiency after C5a stimulation a primer extension experiment was performed. No difference in the length of the extended fragment was detected between LPS and C5a-stimulated RNA, suggesting that the 5'-regions of the RNAs are identical. When LPS- or C5a-stimulated RNA was used to program IL-1 beta synthesis in an in vitro translation system from rabbit reticulocytes, no difference in translational efficiency was observed. Our results indicate that in human monocytes two signals for IL-1 beta gene expression are necessary, a signal for transcriptional activation and another signal to induce translation of the mRNA.

Recombinant human C5a induces transcription but not translation of interleukin-1 beta mRNA in human monocytes.

The effect of recombinant human C5a (rhC5a) on the synthesis of interleukin-1 beta (IL 1 beta) was investigated in highly purified human monocytes, isolated by leukapheresis and counter-current elutriation. RhC5a induced IL 1 beta mRNA synthesis in a dose- and time-dependent manner; maximal induction was achieved at 3 h with rhC5a concentrations of 200 to 500 ng/ml. The IL 1 beta mRNA induction with rhC5a was about 75% of the response observed using lipopolysaccharide (LPS) as the stimulus (300 ng/ml). On the other hand, rhC5a in optimal concentrations only weakly stimulated IL 1 beta protein synthesis, as measured by a two-site-directed enzyme-linked immunoassay. When LPS- or C5a-stimulated RNA was used to program IL 1 beta synthesis in an in vitro translation system from rabbit reticulocytes, no difference in translational efficiency was observed. Our results indicate that, in human monocytes, two signals for IL 1 beta gene expression are necessary, one signal for transcriptional activation and a second signal to induce translation of the mRNA.

Increased secretion of tumor necrosis factors alpha, interleukin 1, and interleukin 6 by human mononuclear cells exposed to beta-galactoside-specific lectin from clinically applied mistletoe extract.

A beta-galactoside-specific lectin from proprietary mistletoe extract, recently reported to exhibit immunomodulatory potency in vivo (T. Hajto, K. Hostanska, and H J. Gabius, Cancer Res. 49: 4803-4808, 1989), induced increased secretion of tumor necrosis factor alpha, interleukin 1, and interleukin 6 in cultures of human peripheral blood mononuclear cells. The enhancement of secretion, determined independently by bioassays and enzyme-linked immunosorbent assay-based quantitation, was caused by selective protein-carbohydrate interaction, as revealed by the strict dependence on the presence of the carbohydrate-binding subunit of the specific lectin-binding sugar as well as anti-lectin antibodies. Increased cytokine levels in serum of patients after injection of optimal lectin doses corroborated the in vitro results. Thus, these data provide an explanation for the increases in cellular parameters of the host defense system in vivo, which presents a further step toward their potentially beneficial clinical exploitation in standardized regimens.

Human immunodeficiency virus type 1 (HIV-1) infection of the central nervous system: an evaluation of cytokines in cerebrospinal fluid.

Cytokines play an important role not only for initiation of immune reactivity but also for development of tissue injury. Of 38 patients infected with human immunodeficiency virus type 1 (HIV-1) interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) were identified in cerebrospinal fluid (CSF) of 22 (58%) and 16 (42%) patients, respectively. Among the IL-1 beta- and IL-6-positive CSF were eight of 15 HIV-1 patients with no clinical signs of central nervous system involvement and four of five patients with acquired immunodeficiency syndrome (AIDS) dementia complex. The presence of IL-6 was often associated with IL-1 beta and soluble interleukin-2 receptor in CSF as well as with intrathecal IgG synthesis. In none of the CSF samples tumor necrosis factor-alpha or interleukin-2 was detected.