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There is increasing interest in tacrolimus-minimization regimens. ASSET was an open-label, randomized, 12-month study of everolimus plus tacrolimus in de-novo renal-transplant recipients. Everolimus trough targets were 3-8 ng/ml throughout the study. Tacrolimus trough targets were 4-7 ng/ml during the first 3 months and 1.5-3 ng/ml (n = 107) or 4-7 ng/ml (n = 117) from Month 4. All patients received basiliximab induction and corticosteroids. The primary objective was to demonstrate superior estimated glomerular filtration rate (eGFR; MDRD-4) at Month 12 in the tacrolimus 1.5-3 ng/ml versus the 4-7 ng/ml group. Secondary endpoints included incidence of biopsy-proven acute rejection (BPAR; Months 4-12) and serious adverse events (SAEs; Months 0-12). Statistical significance was not achieved for the primary endpoint (mean eGFR: 57.1 vs. 51.7 ml/min/1.73 m(2)), potentially due to overlapping of achieved tacrolimus exposure levels (Month 12 mean ± SD, tacrolimus 1.5-3 ng/ml: 3.4 ± 1.4; tacrolimus 4-7 ng/ml: 5.5 ± 2.0 ng/ml). BPAR (months 4-12) and SAE rates were comparable between groups (2.7% vs. 1.1% and 58.7% vs. 51.3%; respectively). Everolimus-facilitated tacrolimus minimization, to levels lower than previously investigated, achieved good renal function, low BPAR and graft-loss rates, and an acceptable safety profile in renal transplantation over 12 months although statistically superior renal function of the 1.5-3 ng/ml tacrolimus group was not achieved., (© 2012 The Authors. Transplant International © 2012 European Society for Organ Transplantation.)

Background: Clinical data are lacking concerning concomitant administration of everolimus and tacrolimus in renal transplant recipients., Methods: In a prospective, multicenter, open-label, exploratory, randomized, 6-month study, 92 de novo renal transplant patients received everolimus, steroids, and basiliximab with low or standard tacrolimus exposure. The primary objective was to compare renal function at 6 months after transplant., Results: Mean 6-month serum creatinine (primary safety variable) was 112+/-31 micromol/L (1.26+/-0.35 mg/dL) and 127+/-50 micromol/L (1.44+/-0.57 mg/dL) in the low and standard tacrolimus groups, respectively, (n.s.); mean estimated GFR (Nankivell) was 75.3+/-16.6 mL/min and 72.5+/-15.2 mL/min (n.s.). Biopsy-proven acute rejection occurred in 13 patients: seven (14%) in the low tacrolimus group and six (14%) in the standard tacrolimus group, n.s. One graft was lost in the standard tacrolimus group. No patients died., Conclusions: Tacrolimus exposure reduction in the presence of everolimus, steroids and basiliximab induction results in good efficacy in de novo renal transplant recipients with very well-preserved renal function. Additional studies are warranted because between-group comparisons were limited by the relatively small differences in tacrolimus exposure in the 2 arms; trough levels were toward the upper end of the low-exposure ranges and toward the bottom of the standard-exposure ranges.

Background: Cyclosporine exposure, as estimated by the area under the curve (AUC), predicts outcomes in renal transplantation. Cyclosporine concentration at two h post-dose (C(2)) has been shown to be the most reliable, single-point surrogate marker for AUC. The objective of this study was to measure renal function beyond month 2 post-transplant using two different C(2) maintenance targets in combination with enteric-coated mycophenolate sodium (EC-MPS), corticosteroids, and basiliximab induction., Methods: In this open-label, multicenter trial, renal transplant recipients entered one of two randomized groups at day 61 post-transplant: group A (higher-C(2) range) or group B (lower-C(2) range)., Results: Patients (164) were recruited, and 141 patients were entered the randomized groups (group A, n = 66; group B, n = 75). At 12 months, the mean calculated creatinine clearance was significantly greater in group B than in group A (79.2 vs. 71.0 mL/min, p < 0.05). Biopsy-proven acute rejection occurred in 14.7% patients in group B and in 24.2% patients in group A (n.s.). During the 12-month trial, 17.7% patients discontinued EC-MPS because of adverse events. Group B (44.0%) had fewer serious adverse events when compared with group A (62.1%; p = 0.04). Overall patient and graft survival were 99.4% and 95.7% respectively. Among 99 high-risk patients (i.e., African-American race, previous transplant, PRA >35% or >4 HLA mismatches), mean creatinine clearance at 12 months was 65.6 mL/min and biopsy-proven rejection occurred in 20.2% patients., Conclusions: Low cyclosporine C(2) levels are associated with improved renal function compared with higher C(2) levels when used in conjunction with EC-MPS, steroids and basiliximab induction. EC-MPS with low cyclosporine C(2) levels, corticosteroids and basiliximab provides excellent renal function with good efficacy even in high-risk patients.

Based on recent evidence that renal cyclooxygenase-2 (COX-2) gene expression is suppressed by immunosuppressive agents such as cyclosporin A (CsA), tacrolimus and dexamethasone, this study aimed to characterize the effect of the new immunosuppressant everolimus on COX-2 expression in the rat kidney. Oral application of everolimus (3 mg kg(-1) day(-1)) to male Sprague-Dawley rats (175-200 g; n=8) for 7 days lowered COX-2 expression in the rat renal cortex and outer medulla, while COX-2 expression in the inner medulla as well as COX-1 expression remained unaltered. Furthermore, everolimus decreased renocortical prostaglandin (PG) E(2) concentration. Everolimus also attenuated the stimulation of renocortical COX-2 expression by furosemide (12 mg day(-1) for 7 days; s.c. via osmotic minipumps), by low salt intake (0.02% NaCl, wt wt(-1)) or by a combination of low salt intake with the AT(1)-receptor antagonist valsartan (30 mg kg(-1) day(-1); oral). In line with these findings, everolimus decreased renocortical PGE(2) concentration during these treatment maneuvers. Everolimus moderately increased natriuresis and diuresis, while the urinary excretion of PGE(2), 6-keto PGF(1alpha) and thromboxane B(2) was decreased. These findings suggest that everolimus inhibits basal and also stimulated expression of renocortical COX-2 and of tissue prostanoid formation. Since inhibition of renal prostanoid formation by everolimus was associated by an increased rather than decreased natriuresis and diuresis, it appears as if everolimus also inhibits tubular salt and water resorption.

Owing to subtle but potentially crucial structural and functional differences between calmodulin (CaM) of different species, the biochemical study of low-affinity CaM-binding proteins from Dictyostelium discoideum likely necessitates the use of CaM from the same organism. In addition, most of the methods used for identification and purification of CaM-binding proteins require native CaM in nonlimiting biochemical quantities. The gene encoding D. discoideum CaM has previously been cloned allowing production of recombinant protein. The present study describes the expression of D. discoideum CaM in Escherichia coli and its straightforward and rapid purification. Furthermore, we describe the optimization of a complete palette of assays to detect as little as nanogram quantities of proteins binding CaM with middle to low affinities. Purified CaM was used to raise high-affinity polyclonal antibodies suitable for immunoblotting, immunofluorescence, and immunoprecipitation experiments. The purified CaM was also used to optimize a specific and sensitive nonradioactive CaM overlay assay as well as to produce a high-capacity CaM affinity chromatography matrix. The effectiveness of this methods is illustrated by the detection of potentially novel D. discoideum CaM-binding proteins and the preparatory purification of one of these proteins, a short tail myosin I., (Copyright 1999 Academic Press.)

Cathepsins B and L are catabolic lysosomal enzymes but are likely candidates for extracellular proteolysis in normal and malignant processes. The signal mediator 12(S)-HETE selectively triggers a shot-gun release of cathepsin B. We have therefore investigated the intracellular distribution of cathepsins in unstimulated and 12(S)-HETE-stimulated tumor cells. Cathepsins B and L have only limited colocalization, which is found in the regions of synthesis and sorting (endoplasmic reticulum, Golgi, trans Golgi network). Treatment by 12(S)-HETE scatters cathepsin B but not cathepsin L and proform of cathepsin B. Colocalization with both mannose 6-phosphate receptors is very limited for both cathepsins. But extensive colocalization of cathepsin B and the endosomal/lysosomal marker CD63 (LIMP-I) documents the main fraction of the enzyme in these compartments. The supposed non-lysosomal fraction of cathepsin B is very likely the secretable material which follows a regulated secretory pathway. Storage and regulated secretion in tumor cells support extracellular proteolysis as a means in invasion which may lead to metastasis. But the mechanisms by which cells might acquire and eventually apply this means is still unknown.

Cathepsins B and L play roles in intracellular and extracellular proteolysis in normal and malignant processes. A directed extracellular proteolysis by regulated secretion could facilitate the process of invasion. We have therefore investigated the effect of the physiological signal mediator 12(S)-hydroxy-eicosatetraenoic acid on the release of cathepsins B and L in normal and malignant human lung cells. Quantitative determinations of cathepsin activities were done by flow cytometry and spectrofluorometry using synthetic dipeptidyl substrates coupled to fluorogens. Most interestingly, a difference in the secretion of cathepsins B and L was found: only release of active cathepsin B was detected. The effect was specific for 12(S)-hydroxy-eicosatetraenoic acid, 12(R)-hydroxy-eicosatetraenoic acid, and 5(S)-hydroxy-eicosatetraenoic acid were ineffective. The response was immediate but a substantial amount of nonreleasable activity remained cell bound. Alveolar macrophages, Wi-38 fibroblasts, and tumor cells derived from large cell carcinomas and adenocarcinomas were sensitive to 12(S)-hydroxy-eicosatetraenoic acid, but cells from undifferentiated squamous cell carcinomas were not. Sensitivity did not parallel malignancy but more likely the degree of differentiation of cells. The investigated tumor cell lines showed no detectable endogenous 12-lipoxy-genase activity to synthesize 12(S)-hydroxy-eicosatetraenoic acid from arachidonate; therefore, we assume a paracrine mechanism for 12(S)-hydroxy-eicosatetraenoic acid action. Protein kinase C alpha, a key enzyme involved in 12(S)-hydroxy-eicosatetraenoic acid-elicited responses, was expressed in all sensitive tumor cells, but insignificantly in a sensitive normal cell line and an insensitive tumor cell line. From our experiments we propose two separate intracellular pools of active cathepsin B: an unreleasable, lysosomal fraction and a fraction available for regulated secretion. Different processing and sorting mechanisms may be responsible for the generation of these cathepsin B-fractions in these pools.

The cysteine proteases cathepsin B and cathepsin L are very likely involved in invasive processes of normal and malignant cells, they become relevant for a number of diseases and are possibly prognostic markers for the outcome of human lung cancer. Therefore, we have determined activities of these related enzymes in cells and in cell extracts of human lung carcinoma cell lines of different cathepsin composition by flow cytometry and by spectrophotometry, respectively. To this end we applied the synthetic dipeptidyl substrates benzoxycarbonyl-arginyl-arginine- and benzoxycarbonyl-phenyl-arginine- coupled to 4-methoxy-beta-naphthylamide, aminomethyl-coumarine or rhodamine R110. The apparent enzymatic activities were differentially defined by protease inhibitors, particularly E-64 and CA-074. Independent of the dipeptidyl-composition more than 99 per cent of the apparent activity was due to cathepsin B when 4-methoxy-beta-naphthylamide or aminomethylcoumarine were the leaving groups. The 4-methoxy-beta-naphthylamide precipitate used for detection of cell associated activities revealed a wide spectrum of excitation to fluorescence thwarting the application of other possible fluorescent tags. Therefore, its application is restricted to uniparametric fluorescence investigations. Both dipeptidylgroups coupled to rhodamine R110 were promiscuous: only 25 to 30% of the apparent activity were due to cathepsin B; the predominant activity came from cathepsin L, irrespective whether intracellular or activities of cellular extracts were analyzed. However, rhodamine R110-coupled substrates open the way for multiparametric fluorescent analysis of cathepsins B and L containing cells if appropriate inhibitors for specification of the enzymatic activities are additionally applied. In very contrast to 4-methoxy-beta-naphthylamide, which causes irreparable damage to the cells, the rhodamine substrates permit studies with living cells and live cell sorting.

The milk incisors of 80 infant-school children were demineralized. For the following 3 weeks the children then rinsed their mouths with mineral solutions. By manifold replica yields (analysis by light- and scanning electron microscope) and colouring tests a positive influence of calcium and phosphorus holding solutions, among others with magnesium, too, on the remineralization was discovered.