Everolimus (RAD001) sensitizes prostate cancer cells to docetaxel by down-regulation of HIF-1α and sphingosine kinase 1

Resistance to docetaxel is a key problem in current prostate cancer management. Sphingosine kinase 1 (SK1) and phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathways have been implicated in prostate cancer chemoresistance. Here we investigated whether their combined targeting may re-sensitize prostate cancer cells to docetaxel.In hormone-insensitive PC-3 and DU145 prostate cancer cells the mTOR inhibitor everolimus (RAD001) alone did not lead to significant cell death, however, it strongly sensitized cells to low levels (5 nM) of docetaxel. We show that mTOR inhibition has led to a decrease in hypoxia-inducible factor-1α (HIF-1α) protein levels and SK1 mRNA. HIF-1α accumulation induced by CoCl2 has led to a partial chemoresistance to RAD001/docetaxel combination. SK1 overexpression has completely protected prostate cancer cells from RAD001/docetaxel effects. Using gene knockdown and CoCl2 treatment we showed that SK1 mRNA expression is downstream of HIF-1α. In a human xenograft model in nude mice single RAD001 and docetaxel therapies induced 23% and 15% reduction in prostate tumor volume, respectively, while their combination led to a 58% reduction. RAD001 alone or in combination with docetaxel has suppressed intratumoral mTOR and SK1 signaling, however as evidenced by tumor size, it required docetaxel for clinical efficacy. Combination therapy was well tolerated and had similar levels of toxicity to docetaxel alone.Overall, our data demonstrate a new mechanism of docetaxel sensitization in prostate cancer. This provides a mechanistic basis for further clinical application of RAD001/docetaxel combination in prostate cancer therapy.

Combination of RAD001 (everolimus) and docetaxel reduces prostate and breast cancer cell VEGF production and tumour vascularisation independently of sphingosine-kinase-1

Resistance to docetaxel is a key problem in current prostate and breast cancer management. We have recently discovered a new molecular mechanism of prostate cancer docetaxel chemoresistance mediated by the mammalian target of rapamycin (mTOR)/sphingosine-kinase-1 (SK1) pathway. Here we investigated the influence of this pathway on vascular endothelial growth factor (VEGF) production and tumour vascularisation in hormone resistant prostate and breast cancer models. Immunofluorescent staining of tumour sections from human oestrogen receptor (ER)-negative breast cancer patients showed a strong correlation between phosphorylated P70S6 kinase (mTOR downstream target), VEGF and SK1 protein expression. In hormone-insensitive prostate (PC3) and breast (MDA-MB-231 and BT-549) cancer cell lines the mTOR inhibitor RAD001 (everolimus) has significantly inhibited SK1 and VEGF expression, while low dose (5 nM) docetaxel had no significant effect. In these cell lines, SK1 overexpression slightly increased the basal levels of VEGF, but did not block the inhibitory effect of RAD001 on VEGF. In a human prostate xenograft model established in nude mice, RAD001 alone or in combination with docetaxel has suppressed tumour growth, VEGF expression and decreased tumour vasculature. Overall, our data demonstrate a new mechanism of an independent regulation of SK1 and VEGF by mTOR in hormone-insensitive prostate and breast cancers.

[Caesarean section in german hospitals: validity of hospital quality report data for monitoring C-section rates]

OBJECTIVE

It is not known if "hospital quality reports" (HQR) document Caesarean (C-) section rates at the hospital level accurately enough for use as a reliable data source when it comes to explaining regional variations of C-sections in Germany by factors at the hospital level. We aimed to answer this question using HQR from hospitals in Baden-Württemberg as data source.

METHOD

Diagnostic and procedure codes from HQR for the year 2008 (HQRdata), were used to calculate numbers of births, numbers of C-sections, and rates of births by C-section (CSR) for 94 of 97 hospitals in Baden-Württemberg. These numbers were compared to internal hospital (IH) data delivered upon request by 80 of 97 hospitals and stemming from vital statistics, birth registry forms, or external quality assurance datasets.

RESULTS

There was no difference in the number of births between HQR data and IH data, but the number of C-sections and the CSR differed significantly (p<0.05; Wilcoxon rank sum test). CSR calculated using HQR data was 4.9 ± 17.9% higher than CSR from IH data (absolute difference 1.5 ± 5.8%). The correlation between the 2 data sources was moderate (r=0.73). Only 55% of the variance in IH data-based CSR was explained by HQR data. The proportion between highest and lowest CSR in hospitals in Baden-Württemberg was 4.9 for HQR data and 3.6 for IH data.

CONCLUSION

There are significant and relevant differences between C-section rates based on ei-ther HQR or IH data. This questions routine data from HQR for 2008 as a reliable data source for research work.

Therapeutic potential of targeting SK1 in human cancers

Sphingosine kinase 1 (SK1) is a lipid enzyme with oncogenic properties that converts the proapoptotic lipids ceramide and sphingosine into the antiapoptotic lipid sphingosine-1-phosphate and activates the signal transduction pathways that lead to cell proliferation, migration, the activation of the inflammatory response, and the impairment of apoptosis. There is compelling evidence that SK1 activation contributes to cancer progression leading to increased oncogenic transformation, tumor growth, resistance to therapies, tumor neovascularization, and metastatic spread. High levels of SK1 expression or activity have been associated with a poor prognosis in several human cancers. Recent studies using cancer cell and mouse models demonstrate a significant potential for SK1-targeting therapies to synergize with the effects of chemotherapy and radiotherapy; however, until recently the absence of clinically applicable SK1 inhibitors has limited the translation of these findings into patients. With the recent discovery of SK1 inhibiting properties of a clinically approved drug FTY720 (Fingolimod), SK1 has gained significant attention from both clinicians and the pharmaceutical industry and it is hoped that trials of newly developed SK1 inhibitors may follow soon. This review provides an overview of the SK1 signaling, its relevance to cancer progression, and the potential clinical significance of targeting SK1 for improved local or systemic control of human cancers.

Constitutive activation and accelerated maturation of peripheral blood T cells in healthy adults in Burkina Faso compared to Germany: the case of malaria?

OBJECTIVE

It is not exactly known how frequent exposure to Plasmodium falciparum shapes the peripheral blood T-cell population in healthy West Africans.

METHODS

The frequency of peripheral blood CD4(+) lymphocytes responding to Plasmodium falciparum merozoite surface protein 1 (PfMSP-1) by production of interferon-gamma (IFN-γ), interleukin-2 (IL-2) or tumor necrosis factor-alpha (TNF-α) was determined using a commercially available flow cytometric activation assay (FastImmune) in 17 healthy adults in Nouna, Burkina Faso. T-cell activation and maturation in peripheral blood of healthy adults in Burkina Faso (n=40) and Germany (n=20) were compared using immunophenotyping and three-colour flow cytometry.

RESULTS

Significant numbers of PfMSP-1 -specific CD4(+) lymphocytes producing IFN-γ, IL-2 and/or TNF-α were detected in 14 healthy adults in Nouna. Cytokine profiles showed predominant production of IFN-γ and TNF-α. Compared to Germans, Burkinabé showed markedly lower proportions of CCR7+ CD45RA+ naive CD4(+) cells and slightly higher frequencies of CD95(+)CD4(+) T-cells and of CD38(+) CD8(+) T-cells. The median antibody-binding capacity of CD95(dim) CD4(+) T-cells in Burkinabé was more than twice the value observed in Germans (263 vs. 108 binding sites per cell, p<0.0001).

CONCLUSIONS

We hypothesize that an IFN-γ-induced increase in the expression level of CD95 on CD4(+) lymphocytes may lower the activation threshold of resting naive CD4(+) T-cells in healthy adults living in Burkina Faso. Bystander activation of these cells deserves further study as a molecular mechanism linking strong IFN-γ responses against Plasmodium falciparum to decreased susceptibility to parasitemia observed in specific ethnic groups in West Africa.

HLA class I antibodies provoke graft arteriosclerosis in human arteries transplanted into SCID/beige mice

Antibodies toward HLA class I and/or MICA are commonly observed in transplanted patients suffering from allograft arteriosclerosis, also called chronic vascular rejection (CVR). The relative importance of cellular versus humoral alloreactivity for CVR is still disputed. We demonstrate that antibodies toward HLA class I provoke lesions typical for CVR in human arteries in vivo in the absence of cellular immunity. To show this, we grafted segments of human mesenteric arteries from 8 deceased organ donors into 36 immunodeficient SCID/beige mice in the infrarenal aortic position. Three mice died postoperatively. The remaining 33 mice received weekly i.v. injections of either a monoclonal antibody toward HLA class I, toward MICA or an irrelevant monoclonal antibody. At sacrifice after 6 weeks, mice receiving the HLA antibody showed a significant neointimal thickening in the grafted artery due to smooth muscle cell (SMC) proliferation while control mice receiving anti-MICA or irrelevant antibody showed little or no thickening. Whereas antibodies toward HLA class I were mitogenic to SMC in vitro, those directed toward MICA did not have any effect. Humoral alloreactivity toward HLA may thus play a causal role for the development of CVR and this opens new possibilities for the treatment of CVR.

Pharmacodynamic evaluation of the first dose of mycophenolate mofetil before kidney transplantation

BACKGROUND AND OBJECTIVES

The effect of mycophenolate mofetil (MMF) on T cell function has not been evaluated in patients undergoing kidney transplantation. The aim of this study was to assess the effect of 1g of MMF on T cell function, that is, intralymphocyte cytokine expression, T cell activation (CD25 and CD71), and T cell proliferation, as well as inosine monophosphate dehydrogenase (IMPDH) activity, to better understand the relationship between pharmacokinetic and pharmacodynamic markers in patients receiving the first dose of MMF before kidney transplantation.

PATIENTS

Twenty-four patients undergoing a kidney transplantation from a living donor were enrolled in this study.

RESULTS

Compared with baseline (before MMF intake), T cell proliferation (93%), IMPDH activity (74%), CD25 (46%), and CD71 (50%) expression significantly decreased during the first hour after MMF intake, in parallel to the rise in MPA concentration. Thereafter, all pharmacodynamic markers, except IMPDH activity, returned back to baseline level. There was a complex inverse relationship between pharmacokinetic and pharmacodynamic markers. The inhibition of T cell proliferation was highly correlated to IMPDH activity, but also to T cell activation markers.

CONCLUSION

The administration of MMF to patients is associated not only with a dramatic decrease in both T cell proliferation and IMPDH activity, but also with in a decrease in CD25 and CD71 expression.

Pharmacodynamic effects of everolimus on anti-CD3 antibody-stimulated T-lymphocyte proliferation and interleukin-10 synthesis in stable kidney-transplant patients

Everolimus (rapamycin derivative, RAD) is a new immunosuppressive drug that prevents allograft rejection. Herein, the pharmacodynamics of everolimus in human renal-allograft recipients is evaluated. Single doses of everolimus (0.75-10mg), combined with a maintenance immunosuppressive therapy based on CyA, decreased lymphocyte proliferation. In addition, the effect of multiple doses of everolimus (0.75-10mg) given daily for 21 days, to stable renal-allograft patients (n=11), was investigated. Everolimus treatment resulted in immediate inhibition (25-55%) of lymphocyte proliferation in renal-allograft recipients; values returning to baseline by 14 days after cessation of everolimus treatment. Placebo-treated patients showed no decrease in lymphocyte proliferation. Interestingly, everolimus reduced IL-10 synthesis by 20-60% in renal-allograft recipients. Phagocytosis rates were not changed by everolimus. In vitro, everolimus inhibited lymphocyte proliferation and IL-10 synthesis dose dependently in anti-CD3 mAb and LPS stimulated peripheral blood mononuclear cell cultures derived from human volunteers.

Pharmacodynamic monitoring of the conversion from mycophenolate mofetil to enteric-coated mycophenolate sodium in stable kidney-allograft recipients

BACKGROUND

The formulations of mycophenolic acid, i.e., mycophenolate mofetil (MMF) and enteric-coated mycophenolate sodium (EC-MPS), seem to have different pharmacokinetic profiles. The aim of this study was to compare the effects MMF and EC-MPS on T-cell proliferation, T-cell activation, T-cell function, and lymphocyte subsets. CLINICAL STUDY AND METHODS: Ten stable kidney-transplant patients on standard maintenance therapy of tacrolimus and MMF (1 g/d), with or without steroids, were converted from MMF to EC-MPS at equivalent dose (720 mg/d). Tacrolimus and steroid doses remained unchanged before, and at 1, 2, 3, and 6 months (M) after conversion. Intra T-lymphocyte cytokines IL-2 and TNF-alpha, lymphocyte-activation surface markers (CD25 and CD71), T-cell proliferation (PCNA+ PI(high)), total lymphocyte count, as well as lymphocytes subsets (CD2, CD3, CD4, CD8, CD19, NK cells) were measured by flow cytometry before conversion and at M1, M2, M3, and M6.

RESULTS

We found no significant differences of MMF versus EC-MPS on lymphocyte function. T-cell proliferation and T-cell activation (CD25 and CD71 expression), but not cytokine expression (TNF-alpha and IL-2), showed a trend to increase after conversion from MMF to EC-MPS. Total lymphocyte, CD2, CD3, CD4, CD8, and NK cells counts were not significantly modified.

CONCLUSION

This study revealed a trend to a lower immunosuppression with EC-MPS as compared to MMF in stable renal transplant patients.

Reconstitution of immunodeficient SCID/beige mice with human cells: applications in preclinical studies

Experimental studies of the in vivo behaviour of human cells and tissues have become possible with the development of immunodeficient mice strains. Such mice accept readily allogeneic or xenogeneic grafts, including grafts of human cells or tissues, without rejection. In this review we describe different immunodeficient mouse strains that have been used for reconstitution by human immune cells. We subsequently go through the experience that we and others have had with reconstitution, and mention the adverse effects, in particular xenogeneic graft versus host reactions. The use of haematopoietic stem cells avoids such reactions but the immunological reconstitution may take several months. We then report the use of immunodeficient mice for the study of chronic vascular rejection of human mesenteric arteries due to cellular or humoral alloreaction. We have shown that SCID/beige mice grafted with a human artery at the place of the aorta developed a thickening of the intima of the human artery after 5-6 weeks, when they were reconstituted with spleen cells from another human donor. The thickening is mainly due to a proliferation of smooth muscle cells. The same type of lesion developed if they received injection of antibodies towards HLA class I antigens. The arteries of the mouse did not develop any lesion. The arterial lesions closely resembled those seen after clinical organ transplantation. Mice that received spleen cells from the same human donor developed little or no lesions. An important aspect of this experimental transplantation model is the possibility to test drugs that may be used in clinical transplantation. In recent experiments we have shown that novel immunosuppressive drugs can inhibit the hyperproliferation of smooth muscle cells in vitro. Preclinical testing in reconstituted SCID/beige mice grafted with human arteries will permit the evaluation of the potential use of these drugs to prevent chronic vascular rejection. The model also allows pharmacodynamic studies that give information on the biological impact of different drugs that may be used in experimental or clinical transplantation.

Tabebuia avellanedae extracts inhibit IL-2-independent T-lymphocyte activation and proliferation

In order to identify new, immune modulating compounds, aqueous extracts of plants pre-selected on ethno-pharmacological knowledge were screened for inhibitory effects in an anti-CD3 driven lymphocyte proliferation assay (MTT-assay). We found for the extract of the inner bark of Tabebuia avellanedae (Tabebuia) dose dependent and reproducible inhibitory effects on lymphocyte proliferation. We further analyzed Tabebuia in flow cytometry based whole blood T-cell function assays. We found that Tabebuia inhibited dose dependent ConA stimulated T-cell proliferation. Decreased T-lymphocyte proliferation was associated with dose dependent reduction of CD25 and CD71 expression on T-lymphocytes. In contrast Tabebuia exerted no effects on cytokine expression (Il-2 and TNF-alpha) by PMA/Ionomycin stimulated T-lymphocytes. Concentrations of Tabebuia used were not toxic for lymphocytes as verified by trypan blue exclusion assay. Further experiments showed that the immune inhibitory effects by Tabebuia were not mediated by its pharmacological lead compound beta-lapachone and only observed in aqueous but not in ethanol plant extracts.

FTY720 (fingolimod) in renal transplantation

FTY720 (Fingolimod) is a novel immunomodulator with a mode of action that is completely different from classical immunosuppressants. FTY is a structural and functional analogue of the natural serum lipid, sphingosine, and is the first in a new class of drugs called sphingosine 1-phosphate receptor (S1P-R) modulators. This review discusses the recent findings on the mechanism of action, preclinical models and outlines the results of the ongoing clinical development program. FTY is highly effective in prolonging allograft survival in preclinical models of transplantation and in experimental models of autoimmune diseases. In clinical trials, this novel compound was investigated in de novo renal transplantation and in multiple sclerosis. Pharmacokinetics are characterized by a prolonged absorption phase, a large volume of distribution, and a long elimination half-life. FTY induces a rapid and transient decrease in lymphocyte counts, which supports the modulatory effects of the drug on lymphocyte sequestration. The most common adverse event was asymptomatic transient bradycardia, a pharmacodynamic effect modulated by atrial S1 P-R. FTY failed to show an improvement in efficacy for the prevention of renal allograft rejection in two large phase III studies. FTY treatment regimens were associated with impaired renal function and the development of macula edema. Consequently, the further development in renal transplantation was stopped. Because initial clinical studies strongly suggest that FTY is highly effective in multiple sclerosis FTY is now being explored in phase III studies for the treatment of demyelinating diseases, Ongoing studies in multiple sclerosis are eagerly awaited because they may provide novel therapeutic options for patients with autoimmune diseases.

Evaluation of a simplified dual-platform flow cytometric method for measurement of lymphocyte subsets and T-cell maturation phenotypes in the population of Nouna, Burkina Faso

In the context of a larger clinical study in Nouna, Burkina Faso, we evaluated a simplified dual-platform (DP) flow cytometric (FCM) method that allows the determination of major lymphocyte subsets in a single test tube. We compared the phenotyping of lymphocytes with DP FCM and simultaneous measurements with standard single-platform (SP) FCM for samples from 177 individuals. Analysis of the comparative measurements revealed that DP FCM systematically underestimates the proportion of NK cells, overestimates the percentage of CD3(+) CD8(+) lymphocytes, and yields proportions of B cells and CD4(+) T cells comparable with the results from SP FCM. Bland-Altman analysis showed a low bias between both methods and an acceptable precision for percent values of CD4(+) T cells (bias +/- precision, -1% +/- 6%) and CD8(+) T cells (-3% +/- 6%). The absolute cell numbers of all lymphocyte subpopulations, however, were systematically biased towards lower values being obtained by DP FCM. Reference values for the distribution of T-cell maturation phenotypes in 177 healthy adults were calculated using DP FCM. The mean +/- standard deviation (SD) CD4(+)-to-CD8(+) T-cell ratio was 1.61 +/- 0.61, the mean percentage +/- SD of CD4(+) T cells was 42% +/- 7%, and that of CD8(+) T cells 29% +/- 7%. Among CD4(+) lymphocytes, 28% +/- 7% were classified as central memory (CD45RA(low) CCR7(+)), 22% +/- 10% as naïve (CD45RA(high) CCR7(+)), 45% +/- 12% as effector memory (CD45RA(low) CCR7(-)); and 5% +/- 3% as terminally differentiated effector memory expressing CD45RA (CD45RA(high) CCR7(-)). Among CD8(bright) lymphocytes, 3% +/- 2% had a central memory phenotype, 27% +/- 13% were naïve, 37% +/- 13% had an effector memory phenotype, and 34% +/- 12% were terminally differentiated effector memory cells expressing CD45RA.

Immunohematological reference values for healthy adults in Burkina Faso

Reference ranges for peripheral blood lymphocyte subsets were generated for 186 healthy adults in Burkina Faso using single-platform flow cytometry. CD4(+) T-cell counts ranged from 631 to 1,696 cells microl(-1); they were lower in males (n = 97) than in females (n = 89), whereas natural killer cell counts were higher.

Current perspectives on FTY720

The search for effective immunosuppressants with fewer side effects continues not only for transplantation, but also for autoimmune diseases. With a novel mechanism of action (sphingosine-1 receptor modulation), oral FTY720 (fingolimod) has the potential to address this need. FTY720 has been preclinically tested with promising results in transplantation and autoimmune disease models. Phase I studies explored the pharmacokinetics and pharmacodynamics of this novel therapeutic concept. Recently, the surprising results of two sister Phase III studies in de novo renal transplant patients, as well as a Phase II study in patients with relapsing multiple sclerosis, were published. This review discusses these findings as well as their implications for the future of sphingosine-1 receptor modulation.

Validation of Immunological Biomarkers for the Pharmacodynamic Monitoring of Immunosuppressive Drugs in Humans

Pharmacodynamic monitoring (PD) can evaluate the efficacy of immunosuppressive drug therapies. In this study, the expressions of PD biomarkers [lymphocyte proliferation, CD25 and CD71 expression, interleukin-2 (IL-2), and tumor necrosis factor-alpha (TNF-alpha) synthesis] were determined in whole-blood assays and were validated for their application in PD of immune modulators in future clinical trials. Initially, the assay conditions were re-evaluated. The measurement of T-lymphocyte proliferation and activation marker expression in whole-blood cultures resulted in optimized stimulation for 72 hours with 7.5 microg/mL concavalin A. Intracellular cytokine expression of CD3+ T-cells received optimized stimulation for 4 hours with 15 ng/mL phorbol 12-myristate 13-acetate and 0.75 microg/mL ionomycin. Statistical assay parameters (intra-assay, intra-individual, and interindividual variabilities) were determined. It was found that blood storage for up to 24 hours is possible without any change in biomarker expression. Dosage effects of immunosuppressive drugs (tacrolimus, cyclosporin A, sirolimus, mycophenolic acid, and methylprednisolone) were evaluated in vitro and the assay was applied successfully to dialysis, renal transplant, and liver transplant patients. We conclude that these biomarkers used in whole-blood assays are suitable for PD of immune modulators in clinical trials.

Die Neugeborenensepsis in DRG-System

INTRODUCTION

The introduction of Diagnosis Related Groups in Germany (G-DRG) has brought forward the obligation for physicians to take into account an intricate system of medical, economical and legal implementations. Mistakes in the process of encoding the principal diagnosis or procedures may have financial consequences. Problems to determine the correct ICD-code will be most prominent for diseases with poorly defined or even inconsistent diagnostic criteria as is the case for neonatal septicemia. We decided to evaluate whether the introduction of G-DRG resulted in a change of frequency of the diagnosis "neonatal septicemia".

METHODS

We analysed data derived from the quality assurance program "Neonatalerhebung" in the state of Baden-Württemberg during the years of 2001 through 2004, i. e., 2 years before and 2 years during the introduction of G-DRG. During this period an annual number of 12,316 up to 13,172 newborns were admitted to the participating hospitals.

RESULTS

The mean number of diagnoses per patient increased from 2.2 to 3.8. The frequency of the diagnosis of septicemia remained constant. The percentage of newborns receiving antibiotic therapy did not change. The ratio of cases with "septicemia yes" over "antibiotics yes" did not change. Although it is difficult to determine the diagnosis of neonatal septicemia and in spite of the economic implications of this diagnosis, no change in the frequency of this diagnosis occurred during the introduction of DRG.

CONCLUSIONS

Assuming that the participating hospitals used an identical database for the quality assurance program "Neonatalerhebung" and for accounting, we conclude that the DRG system is stable with respect to neonatal septicemia.

Differential effects of single dose FTY720 on CD62L+ B-cells in stable renal allograft recipients

FTY720, a sphingosine-1-phosphate receptor agonist, is the archeotype of a new class of immune modulators, which redirects lymphocytes from the peripheral blood into secondary lymphatic tissue. Previously, it was shown that FTY720 differentially decreases peripheral T-cells, expressing specific chemokine and adhesion receptors. Here, we investigated the effect of single doses FTY720 on peripheral B-cells expressing CD62L, CD11a, CD49d and CXCR4 in stable human renal allograft recipients. Peripheral blood lymphocytes were isolated by Ficoll density centrifugation and stained with monoclonal antibodies against CD3 or CD19 and CD62L, CD11a, CD49d, CXCR4 to determine the percentage of these T- and B-cell subpopulations. Total lymphocyte counts were measured by routine laboratory diagnostics to calculate absolute lymphocyte subset counts. In FTY720 treated patients, total lymphocyte counts decreased by 31.8% (0.25-2 mg) and 60.4% (3.5 mg), and total T-cell counts by 38.8% (0.25-2 mg) and 70.9% (3.5 mg). In comparison, total B-cell counts decreased by 32.2% (0.25-2 mg) and 61.1% (3.5 mg). The reduction of CD62L+ B-cells was less pronounced as compared to CD62L+ T-cells (0.25-2 mg: 15.7% vs. 57.3%; 3.5 mg: 57.2% vs. 86.9%). CD11a+ B-cells decreased by 15.4% (0.25-2 mg) and 57.1% (3.5 mg), and CD49d+ B-cells by 15.0% (0.25-2 mg) and 56.7% (3.5 mg). CXCR4+ B-cells decreased by 19.9% (0.25-2 mg) and 57.2% (3.5 mg). In vitro experiments showed that FTY720 did not change the mean expression of CD62L, CD11a, CD49d and CXCR4 on CD19+ B-cells. In conclusion FTY720 treatment reduces B-cells expressing CD62L to a significant lesser degree than T-cells expressing CD62L.

Effect of Mycophenolate Mofetil Monotherapy on T-Cell Functions and Inosine Monophosphate Dehydrogenase Activity in Patients Undergoing a Kidney Transplantation

The aim of this study was to assess the effects of 1 g of mycophenolate mofetil (MMF) on T-cell function and inosine monophosphate dehydrogenase (IMPDH) activity among patients undergoing kidney transplantation. Five patients undergoing renal transplantation from a living donor were enrolled in this study. Compared to baseline (before MMF intake), CD25 and CD71 expression were significantly decreased during the first hour following MMF intake. T-cell proliferation and IMPDH activity also decreased dramatically. Thereafter, all biomarker levels increased over time. At 4 hours, CD25 and CD71 levels, as well as IMPDH activity, returned to almost baseline values, whereas T-cell proliferation remained below baseline. Intracytoplasmic IL-2 expression remained unchanged after MMF ingestions. In conclusion, administration of 1 g of MMF was associated with a transient decrease in CD25 expression in addition to a temporary dramatic decrease in both T-cell proliferation and IMPDH activity.

Profibrotic cytokines and lymphocyte proliferation in stable renal allograft recipients treated with or without cyclosporine A

Profibrotic cytokines such as transforming growth factor-beta 1 (TGF-beta1) and endothelin-1 (ET-1) are involved in the pathogenesis of chronic allograft nephropathy. We assessed the effect of maintenance immunosuppression with or without cyclosporine A on TGF-beta1 and ET-1 expression as well as lymphocyte proliferation in renal allograft recipients. Patients were divided into groups according to their maintenance immunosuppression: A, azathioprine + methylprednisolone; B, cyclosporine A + azathioprine + methylprednisolone. TGF-beta1 and ET-1 plasma concentrations were not different between both groups. TGF-beta1 concentrations in cell culture supernatants and lymphocyte proliferation were higher in group B as compared to group A. No correlation was found between TGF-beta1 plasma concentrations and lymphocyte proliferation. Multiple linear regression analysis revealed that patient characteristics influence TGF-beta1 and ET-1 expression. In conclusion, plasma levels of profibrotic cytokines do not reflect the existing profibrotic potential of immunosuppressive drugs. Demographic factors and the employed co-medication confound the results.

FK506, transforming growth factor-β1 and mesangial matrix synthesis: Parallels and differences compared with cyclosporine A

Cyclosporine A (CsA)-induced glomerulosclerosis is a well-described side effect of CsA treatment. Current evidence indicates that FK506 causes similar morphologic changes. Recently, we demonstrated that CsA up-regulates the expression of transforming growth factor-beta1 (TGF-beta1), its receptors type I (TbetaR-I) and type II (TbetaR-II), as well as related matrix protein synthesis in mesangial cells (MCs). Here, we assessed the effect of FK506 on the expression of TGF-beta1, TbetaR-I, TbetaR-II, fibronectin (FN) and plasminogen activator inhibitor type-1 (PAI-1) in MCs. Resting MCs were incubated with/without FK506. Time- and concentration-dependent expression was measured at the mRNA and protein level. Compared to untreated controls, FK506 stimulated TGF-beta1 mRNA (maximum at 8 h, 100 ng/mL: 2.13+/-0.15-fold, P<0.005) and protein expression (maximum at 96 h, 100 ng/mL: 1.96+/-0.29-fold, P<0.005). In contrast, TbetaR-I and TbetaR-II protein expression remained unchanged. Concerning matrix protein synthesis, FK506 slightly increased FN production (96 h, 100 ng/mL: 1.38+/-0.28-fold, P<0.05), but not PAI-1 production. These results indicate that, comparable to CsA, FK506 induced glomerulosclerosis is also due to a direct effect on mesangial matrix production, which is at least in part mediated via up-regulation of TGF-beta1 expression. The fact that, unlike CsA, FK506 does not increase the expression of TbetaR-I, TbetaR-II, and PAI-1, deserves further investigation.

Qualitätsprüfungen ambulanter Pflegedienste in Baden-Württemberg - Überblick über die Erfahrungen aus 6 Jahren flächendeckender Untersuchungen durch den MDK

During the years 1997 to 2003 the medical services of the statutory health insurance in the German Federal State of Baden-Württemberg carried out a total survey regarding structure, process and outcome with regard to the quality of care of outpatients in the German long-term care insurance system. This survey provides information on the development of the quality of care. All outpatient nursing services licensed by the statutory long-term care insurance funds in Baden-Württemberg (n (1997 - 2000) = 863; n (2000 - 2003) = 779) were subjected to a uniform assessment based on a consented concept applied in all German Federal States. Our results demonstrate a tendency to fewer but larger nursing services providing care for an increasing number of patients. Qualification of head nurses and of caregiving staff in general has significantly improved. Information for the patient/consumer on the conditions of contracts which have to be made between a nursing service and the patient is still deficient in more than 20 % of cases. Adherence to proper procedures in the process of nursing has improved, especially with respect to taking a complete medical/nursing history and defining the individual resources of a patient and aims for therapy/nursing. However, only in (1/3) of the cases could we find a documentation of continuous adaptation of the planning of therapy. Efforts of in-house quality management and internal quality assurance by the outpatient nursing services have improved. Regarding the outcome of nursing there has been a decrease in the provision of stimulating care from 87 % of cases to 75 %. The majority of patients of outpatient nursing services do not receive benefits of the long-term care insurance system but of the statutory health insurance. This fact underlines the importance of a general conceptual framework for internal and external quality assurance.

Mycophenolate mofetil slows progression in anti-thy1-induced chronic renal fibrosis but is not additive to a high dose of enalapril

Tubulointerstitial inflammation and fibrosis are hallmarks of chronic progressive renal diseases. To characterize the functional interaction between cell infiltration and matrix expansion, this study compared the immunosuppressant mycophenolate mofetil (MMF), intended as primarily anti-inflammatory intervention, the angiotensin-converting enzyme inhibitor enalapril, intended as primarily an anti-fibrotic drug, and a combination of both as anticipated anti-inflammatory/anti-fibrotic intervention. The model used was anti-thy1-induced chronic-progressive glomerulosclerosis (cGS) in the rat, where a brief anti-thy1-induced glomerular injury progresses spontaneously toward tubulointerstitial fibrosis and renal insufficiency. cGS was induced by injection of anti-thy1 antibody into uninephrectomized Wistar rats. One week after disease induction, animals were randomly assigned to the following groups: cGS, cGS plus MMF (20 mg·kg body wt−1·day−1), cGS plus high-dose enalapril (12 mg·kg body wt−1·day−1), and cGS plus both. At week 16 after disease induction, MMF or enalapril alone reduced signs of chronic renal disease significantly and similarly compared with the untreated cGS group. Variables measured included proteinuria, blood pressure, tubulointerstitial and glomerular matrix accumulation, expression of transforming growth factor-β1, fibronectin, and plasminogen activator inhibitor-1, infiltration of lymphocytes and macrophages, plasma creatinine and urea levels, and glomerular filtration rate. Combined MMF and enalapril treatment was not superior to single therapy. In conclusion, MMF slows the progression of chronic renal fibrosis and renal insufficiency as effectively as high-dose enalapril in the anti-thy1-induced chronic-progressive glomerulosclerosis model. The dual anti-inflammatory/anti-fibrotic intervention does not yield additive renoprotective effects, indicating that MMF and enalapril interfere with similar or very closely related pathways involved in progression of renal disease.

Novel mediators of FTY720 in human lymphocytes

FTY720 (FTY), a novel immunosuppressive drug, can be distinguished from other immunosuppressive drugs by a completely different mechanism of action. FTY induces altered lymphocyte trafficking, leading to peripheral blood lymphopenia and to increased lymphocyte counts in lymph nodes. FTY mediates its immune-modulating effects by binding to sphingosine 1-phosphate receptors expressed on lymphocytes. In an attempt to identify mediators of the FTY-induced signal transduction, we used a proteomic approach. FTY-treated peripheral blood lymphocytes (PBLs) were investigated for the expression of 622 proteins. We identified 15 differentially expressed proteins in PBLs possibly related to FTY action. As indicated by protein function, several identified proteins could be linked to the cytoskeleton/cell motility, to cell adhesion, and vesicle trafficking. No changes were found concerning the expression of various apoptosis regulators as well as the immunophilins FKBP12 and calcineurin. Our data suggest that FTY affects cytoskeleton rearrangements, cell adhesion, and vesicle trafficking/sorting in human PBLs.

Qualitätskriterien für ambulante Schulungsprogramme für übergewichtige und adipöse Kinder und Jugendliche

BACKGROUND

In Germany, 9 to 12 % of all children between five and seven years of age have been shown to be overweight at school entry; 2.5 to 3.5 % of them are obese. Therapeutic intervention for obese children and adolescents is considered to be indicated especially in cases where an increased body mass index (BMI) is accompanied by a disease the effective treatment of which requires weight loss. Furthermore, the child and its family must be willing to actively change their habits.

OBJECTIVE

A multitude of health care providers have begun to offer multidisciplinary group programme for prevention and treatment of obesity to affected individuals and their families. The Medical Service of the Statutory Health Insurance (MDK) has therefore developed a list of quality and assessment criteria for such programme.

METHODS

A systematic search for information in international and national publications was performed using standard methodology of evidence-based medicine. Data were extracted and assessed according to pre-defined criteria taking into consideration previously published clinical guidelines and opinions of expert panels.

RESULTS

Nearly all available studies were of low internal validity and mostly of poor methodological quality. Therefore, no binding recommendations for the design of health education programme for overweight and obese children and adolescents can be given. Potentially successful intervention should combine the following 4 modules: nutrition, physical activity, change of eating habits, physical activity habits and life style using methods of behavioural therapy, and involvement of parents. Such combinations may have the potential to reduce or stabilise the BMI at least during a defined period of time. In younger children, the beneficial effect will be more pronounced if the parents are actively involved.

CONCLUSION

Up to now informative studies have not reliably shown that the effect of ambulatory health education programmes for overweight and obese children and adolescents and their parents may last for more than one or two years. Therefore, a controlled clinical trial determining the long-term effectiveness of such programme is imperative. The decision whether a defined programmes should be included in such a study could be taken on the basis of the quality indicators and assessment criteria described here.

FTY720-induced lymphocyte homing modulates post-transplant preservation/reperfusion injury

BACKGROUND

A novel immunomodulator, FTY720, modulates lymphocyte migration to injured tissues via enhanced lymphocyte sequestration to secondary lymphoid organs. We tested whether or not single-dose FTY720 (0.5 mg/kg) pretreatment rescues renal grafts from post-transplant preservation/reperfusion injury.

METHODS

Rat renal grafts were cold-preserved in University of Wisconsin (UW) solution for 4 hours and then transplanted into syngeneic or allogeneic recipients that received a single dose of FTY720 24 hours before transplantation. Flow cytometry analysis of peripheral blood and lymph nodes was performed to confirm the biologic effect of FTY720. Grafts were harvested after 24 hours. Renal sections were examined histologically and stained for intracellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1), platelet endothelial cellular adhesion molecule-1 (PECAM-1), major histocompatibility complex (MHC) class II, and inflammatory cells. Interleukin-1 (IL-1) production was determined in renal protein extracts.

RESULTS

FTY720 pretreatment significantly increased CD3+ T-cell sequestration to lymph nodes in the face of peripheral lymphopenia. Isografts and allografts from the FTY720-treated groups did not develop increased creatinine (0.55 +/- 0.12 in isografts and 0.62 +/- 0.08 mg/dL in allografts), compared with vehicle controls (2.28 +/- 0.20 in isografts and 2.24 +/- 0.18 mg/dL in allografts). Kidneys from FTY720-treated groups also showed lower acute tubular damage scores. Furthermore, FTY720 decreased neutrophil influx, although circulating neutrophils were unchanged. FTY720 also prevented postischemic IL-1 intragraft production not affecting infiltration with recipient ED-1+ macrophages and MHC class II-positive cells. Expression of ICAM-1, VCAM-1, and PECAM did not differ among groups.

CONCLUSION

FTY720 ameliorated morphologic and functional consequences of post-transplant reperfusion injury. Thus, FTY720-induced peripheral T-cell absence may influence intragraft IL-1 production and neutrophil infiltration, despite proadhesive endothelial properties. FTY720 may broaden the utility in renal transplantation as a pretreatment strategy against preservation/reperfusion injury.

FTY720 MEDIATES APOPTOSIS-INDEPENDENT LYMPHOPENIA IN HUMAN RENAL ALLOGRAFT RECIPIENTS: DIFFERENT EFFECTS ON CD62L+ AND CCR5+ T LYMPHOCYTES

BACKGROUND

The sphingolipid FTY720 (FTY), a novel immune modulator, induces lymphopenia and prevents allograft rejection. This study was designed to study the effect of FTY on lymphocyte subpopulations and apoptosis in stable renal allograft recipients.

METHODS

Stable renal allograft recipients received a single oral dose of 0.25 to 3.5 mg of FTY (n= 13) or placebo (n= 3). Whole blood was drawn immediately before and at 4, 8, 12, 24, 72, and 96 hr after administration. The number of lymphocyte subpopulations, with an emphasis on surface markers involved in lymphocyte migration, was analyzed by flow cytometry. Apoptotic lymphocytes were detected following Annexin V-FITC/PI staining. Lymphocyte mobility was investigated in a modified Boyden chamber.

RESULTS

FTY induced a transient lymphopenia by an apoptosis-independent mechanism. In vitro experiments with peripheral blood mononuclear cells (PBMC) confirmed that clinically relevant concentrations of FTY (0.1 microM) increased lymphocyte mobility, whereas only suprapharmacologic concentrations of FTY (10 microM) could induce apoptosis. FTY-treated patients had reversible changes in the composition of peripheral lymphocyte subpopulations. CD62L+ T cells decreased to the greatest extent (-57%). In contrast, CCR5+ T-cell counts declined only marginally (-10%). In vitro, treatment of PBMC with FTY (1 mM-10 microM) did not induce changes in the expression of these surface markers.

CONCLUSIONS

The data indicate that FTY mediates apoptosis-independent lymphopenia in human renal allograft recipients. FTY-induced lymphopenia preferentially affects CD62L+ and CCR5- T-lymphocyte subpopulations.

FTY720 exerts differential effects on CD4+ and CD8+ T-lymphocyte subpopulations expressing chemokine and adhesion receptors

BACKGROUND

FTY720 (FTY), a novel immunomodulator with the potential to improve immunosuppressive therapy after organ transplantation, is currently under clinical investigation. Previous experimental animal studies have shown that FTY has a unique mechanism of action associated with altered lymphocyte recirculation.

METHODS

Participating in a phase I clinical trial, we studied the pharmacodynamic effects of FTY in stable renal allograft recipients. We analysed the effect of FTY on surface marker expression on T-cell subpopulations by flow cytometry.

RESULTS

A single oral dose of FTY (0.25-3.5 mg) significantly reduced peripheral lymphocyte counts by 30-70%. FTY reduced all T-lymphocyte subsets, CD4(+) cells more than CD8(+) cells. However, we observed that lower doses of FTY (0.25-2 mg, n = 11) did not affect peripheral CD4(+)CCR5(+) T-lymphocyte counts, while the highest FTY dose of 3.5 mg (n = 2) exerted a rapid reduction of CD4(+)CCR5(+) cells. Peripheral CD8(+)CCR5(+) T-lymphocyte counts were reduced by either low (0.25-2 mg) or high (3.5 mg) doses of FTY. In contrast to CCR5(+) cells, cells expressing CD62L were preferentially reduced after administration of FTY. In particular, CD4(+)CD62L(+) T cells declined after treatment. CD4(+) and CD8(+) T-lymphocyte subpopulations expressing the other chemokine and adhesion receptors (CXCR4, CD11a and CD49d) were reduced to a similar extent as compared with overall CD4(+) or CD8(+) T-lymphocyte counts.

CONCLUSIONS

Despite the limited number of patients, especially in the placebo (n = 3) and the high-dose groups (n = 2), our observations suggest that FTY exerts differential effects on T-cell subpopulations. FTY predominantly reduces CD4(+)CD62L(+) cells in the peripheral blood suggesting increased migration into lymph nodes. It seems that only FTY doses above 2 mg are able to reduce peripheral CD4(+)CCR5(+) T lymphocytes, which are potentially capable of infiltrating into the allograft during rejection.

The immunosuppressive potential of misoprostol--efficacy and variability

Existing evidence on the immunosuppressive efficacy of prostaglandin E (PGE) and its analogues in vivo is conflicting. We investigated the effect of misoprostol, an orally available PGE1 analogue, on T-cell proliferation, Th cell-derived cytokine production, and phagocytosis in healthy volunteers. All participants (n=20) received increasing doses of misoprostol (0-400 microg). Blood was drawn before and after intake. Misoprostol intake caused a time- and dose-dependent reduction of anti-CD3-stimulated cell proliferation. Whereas the synthesis of Th1 cytokines (IL-2 and IFN-gamma) was dose-dependently reduced, IL-10 expression was increased at lower misoprostol doses. Concerning IL-4 expression, we observed an increased IL-4 production in males, but a decreased IL-4 production in females. Misoprostol intake also reduced phagocytosis activity in a dose-dependent manner. At least in part our results explain the immunosuppressive effects of misoprostol observed in vivo. The considerable interindividual variability as well as gender-specific differences seem to account for the variability of clinical study results.