Michael Koziolek

Tumoural CXCL16 expression is a novel prognostic marker of longer survival times in renal cell cancer patients

The aim of our study was to analyse the expression of CXCL16, ADAM10 and CXCR6 in renal cell carcinoma (RCC) tissue and to correlate the expression pattern with clinicopathologic data, including patient survival. Furthermore, we investigated CXCL16, ADAM10 and CXCR6 expressions by FACS, immunofluorescence and ELISA analysis in renal carcinoma cell lines. Our immunohistochemical analysis on tissue microarray of renal cancer samples of 104 patients revealed that ADAM10 correlated significantly with tumour stage, pathological nodal status, M status and lymphangiosis carcinomatosa. CXCL16, CXCR6 and ADAM10 were significantly increased in papillary carcinomas. Importantly, high levels of CXCL16 expression in renal cancer tissue correlated with better survival of patients, and CXCL16 correlated inversely to the tumour stage. In addition, inhibition of CXCL16 induced the migration of renal cancer cells assuming an anti-migratory function of transmembrane CXCL16. Taken together, our data demonstrate that downregulation of CXCL16 plays an important role in renal cancer development and progression, and that CXCL16 in RCC is an independent prognostic marker for better patient survival.

Characterization of CXCL16 and ADAM10 in the normal and transplanted kidney

The chemokine CXCL16 plays an important role in the recruitment of leukocytes to sites of inflammation influencing the course of experimental glomerulonephritis. Here we show that human kidneys highly express CXCL16 in the distal tubule, connecting tubule and principal cells of the collecting duct with weak expression in the thick ascending limb of Henle. Beside the membrane localization, a soluble form of CXCL16 can be proteolytically released which acts as a chemotactic factor. In human renal tissue the expression pattern of the disintegrin-like metalloproteinase ADAM10 is similar to that of CXCL16, suggesting ADAM10 can potentially cleave CXCL16 in vivo. When we tested this in primary tubular cells we found that blockade of ADAM10 activity inhibited the IFN-gamma induced release of soluble CXCL16. Acute tubular damage in renal allografts was associated with elevated urinary CXCL16 and this correlated with focally increased apical CXCL16 expression in the distal tubules and collecting ducts. Renal allograft biopsies, with a histopathological diagnosis of acute interstitial rejection, showed increased basolateral ADAM10 expression together with high numbers of infiltrating T cells. Our results suggest that CXCL16 and ADAM10 are involved in the recruitment of T cells to the kidney and play an important role in inflammatory kidney diseases.

Immunoadsorption therapy in patients with multiple sclerosis with steroid-refractory optical neuritis

BackgroundIn multiple sclerosis relapses refractory to intravenous corticosteroid therapy, plasma exchange is recommended. Immunoadsorption (IA) is regarded as an alternative therapy, but its efficacy and putative mechanism of action still needs to be established.MethodsWe prospectively treated 11 patients with multiple sclerosis who had optical neuritis and fulfilled the indications for apheresis therapy (Trial registration DE/CA25/00007080-00). In total, five IA treatments were performed using tryptophan-IA. Clinical activity (visual acuity, Expanded Disability Status Scale, Incapacity Status Scale), laboratory values and visual evoked potentials were measured before, during and after IA, with a follow-up of six months. Moreover, proteomic analyses were performed to analyze column-bound proteins as well as corresponding changes in patients’ sera.ResultsAfter the third IA, we detected an improvement of vision in eight of eleven patients, whom we termed responders. Amongst these, the mean visual acuity improved from 0.15 ± 0.12 at baseline to 0.47 ± 0.32 after the third IA (P = 0.0252) up to 0.89 ± 0.15 (P < 0.0001) at day 180 ± 10 after IA. Soluble interleukin-2 receptor decreased in responders (P = 0.03), whereas in non-responders it did not. Proteomic analyses of proteins adsorbed to IA columns revealed that several significant immunological proteins as well as central nervous system protein fragments, including myelin basic protein, had been removed by IA.ConclusionsIA was effective in the treatment of corticosteroid-refractory optic neuritis. IA influenced the humoral immune response. Strikingly, however, we found strong evidence that demyelination products and immunological mediators were also cleared from plasma by IA.

Retrospective Analysis of Long‐term Lipid Apheresis at a Single Center

We retrospectively analyzed 10 906 lipid apheresis sessions (heparin‐induced lipoprotein precipitation, direct adsorption of lipoproteins, double filtration plasmapheresis, dextran sulfate adsorption, and immunoadsorption) in 38 patients who were consecutively treated in our department during the last 20 years. The incidences of major cardiovascular events (MACE) (death, cerebrovascular accident, myocardial infarction, limb amputation, and renal vascular involvement) were taken separately as primary end‐points or as a combined end‐point. The time‐course of secondary end‐points (coronary and extracranial status of arteries, left ventricular function, occlusive artery disease, and calculated glomerular filtration rate [cGFR]) were also evaluated, as well as the extent of the reduction in plasma lipids and lipoproteins and the incidence of therapy associated side‐effects. MACE decreased from 7.02% events per patient per year at the start of lipid apheresis to 1.17% during lipid apheresis and the rate of myocardial revascularization decreased from 22.8% to 3.8% per patient per year. Classical (diabetes mellitus, arterial hypertension, and smoking history), as well as novel risk factors (cGFR < 60 mL/min, statin withdrawal, mixed hyperlipoproteinemia, and elevated lipoprotein (a)) were associated with an elevated risk for MACE. All applied methods had comparable effects. All lipid apheresis methods proved to be safe and suitable for long‐term treatment. The present data demonstrate that treatment with lipid apheresis is very effective and leads to long‐term reduction in cardiovascular mortality and morbidity. 

Predictors of complications in therapeutic plasma exchange

Plasma exchange (PE) is used for blood purification to modulate proteins involved in pathological processes. As the number of patients receiving PE treatment and the heterogeneity of the underlying diseases is steadily increasing, we evaluated the most frequent complications and analyzed causes leading to adverse reactions. 883 PE procedures in 113 patients between the years 2000 to 2006 were retrospectively analyzed with respect to complications. Additionally, underlying diseases and settings of PE procedure were analyzed to identify high‐risk patients and respective PE settings. A total of 226 adverse reactions were recorded (25.6% of all PE procedures). Most complications were mild (n = 121, 13.7%) or moderate (n = 98, 11.0%). In seven cases (n = 7, 0.7%), severe, life‐threatening adverse events were induced by PE either due to severe allergic reactions (n = 4, 0.5%) or to sepsis (n = 3, 0.3%). Patients with neurologic diseases had a significantly higher risk to develop complications compared to those with internal diseases (P = 0.013). This was due to a higher rate of PE associated adverse events (in particular hypotension) and complications associated with vascular access. Among patients from internal medicine those with hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) had the highest risk to develop complications. Patients with neurological diseases compared to those with medical conditions and patients with HUS/TTP compared to those with other diseases had a higher risk to develop complications. However, severe adverse events are rare. Thus, PE seems to be a safe and recommendable procedure. J. Clin. Apheresis, 2009.

Effects of Baroreflex Activation Therapy on Ambulatory Blood Pressure in Patients With Resistant Hypertension

Baroreflex activation therapy (BAT) has been demonstrated to decrease office blood pressure (BP) in the randomized, double-blind Rheos trial. There are limited data on 24-hour BP changes measured by ambulatory BP measurements (ABPMs) using the first generation rheos BAT system suggesting a significant reduction but there are no information about the effect of the currently used, unilateral BAT neo device on ABPM. Patients treated with the BAT neo device for uncontrolled resistant hypertension were prospectively included into this study. ABPM was performed before BAT implantation and 6 months after initiation of BAT. A total of 51 patients were included into this study, 7 dropped out from analysis because of missing or insufficient follow-up. After 6 months, 24-hour ambulatory systolic (from 148±17 mm Hg to 140±23 mm Hg, P<0.01), diastolic (from 82±13 mm Hg to 77±15 mm Hg, P<0.01), day- and night-time systolic and diastolic BP (all P⩽0.01) significantly decreased while the number of prescribed antihypertensive classes could be reduced from 6.5±1.5 to 6.0±1.8 (P=0.03). Heart rate and pulse pressure remained unchanged. BAT was equally effective in reducing ambulatory BP in all subgroups of patients. This is the first study demonstrating a significant BP reduction in ABPM in patients undergoing chronically stimulation of the carotid sinus using the BAT neo device. About that BAT-reduced office BP and improved relevant aspects of ABPM, BAT might be considered as a new therapeutic option to reduce cardiovascular risk in patients with resistant hypertension. Randomized controlled trials are needed to evaluate BAT effects on ABPM in patients with resistant hypertension accurately.

Effects of baroreflex activation therapy on arterial stiffness and central hemodynamics in patients with resistant hypertension.

Background: High central blood pressure, augmentation index and pulse wave velocity are independent cardiovascular risk factors. Little is known of the effect of baroreflex activation therapy on central hemodynamics. Method: In this prospective clinical trial, radial artery applanation tonometry and pulse wave analysis were used to derive central aortic pressure and hemodynamic indices (i.e. augmentation pressure, augmentation index, pulse wave velocity, systolic and diastolic pressure time integral, subendocardial viability index) at baseline and 6 months after starting baroreflex activation therapy in 25 patients with resistant hypertension. Results: Apart from peripheral blood pressure reduction, 6 months of baroreflex activation therapy significantly reduced mean central aortic blood pressure from 109.7 ± 20.5 to 97.4 ± 18.8 mmHg (P < 0.01) and aortic pulse pressure from 62.9 ± 18.6 to 55.2 ± 16.0 mmHg (P < 0.01). Aortic augmentation pressure and augmentation index at a heart rate of 75 b.p.m. were significantly reduced by 4.3 ± 7.9 mmHg (P = 0.01) and 3.5 ± 6.8% (P = 0.02). Additionally, pulse wave velocity decreased from 10.3 ± 2.6 to 8.6 ± 1.3 m/s (P < 0.01) 6 months after starting baroreflex activation therapy. Systolic pressure time integral was significantly reduced (P = 0.03), whereas subendocardial viability index remained unchanged. Conclusion: Apart from peripheral blood pressure, baroreflex activation therapy reduces central blood pressure, augmentation index at a heart rate of 75 b.p.m. and pulse wave velocity in patients with resistant hypertension, suggesting strong potential to reduce cardiovascular risk.

Impact of Baroreflex Activation Therapy on Renal Function - A Pilot Study

Background/Aims: Resistant hypertension and chronic kidney disease (CKD) are interlinked via sympathetic overdrive. Baroreflex activation therapy (BAT) has been shown to chronically reduce blood pressure (BP) in patients with resistant hypertension. The effect of BAT on renal function in CKD patients with resistant hypertension has not been reported. The aim of this study was to investigate the effect of sympathetic inhibition on renal function in CKD patients. Methods: 23 CKD patients with resistant hypertension were prospectively treated with BAT. Analyses were performed before and 6 months after the start of BAT. The renal function was analyzed by creatinine, cystatin C, glomerular filtration rate (GFR), renin, aldosterone, fractioned and 24-hour sodium excretion and analyses of urine marker proteins. The purpose of the control group was to investigate the influence of treating patients in a center for hypertension and regression to the mean on investigated variables. Results: The office mean BP decreased from 116.9 ± 20.9 mm Hg to 104.2 ± 22.2 mm Hg (p < 0.01), while the number of prescribed antihypertensive classes decreased from 6.6 ± 1.6 to 6.1 ± 1.7 (p = 0.02). Proteinuria and albuminuria decreased from a median of 283.9 and 47.7 to 136.5 (p = 0.01) and 45.0 mg/g creatinine (p = 0.01) with pronounced effects in higher CKD stage III + IV compared to I + II (p < 0.01). CKD-EPI cystatin C equation improved from 53.6 ± 22.7 to 60.4 ± 26.1 ml/min (p = 0.02). While creatinine and GFR were impaired after a period of 6 months, no changes of proteinuria, albuminuria, or BP were obtained in control patients. Conclusion: The data of this prospective trial demonstrate potential nephroprotective effects of BAT in therapy-resistant hypertension in CKD patients by a reduction of BP, proteinuria and moreover, a stabilization of estimated GFR.

Induction of Tet3-dependent Epigenetic Remodeling by Low-dose Hydralazine Attenuates Progression of Chronic Kidney Disease

Progression of chronic kidney disease remains a principal problem in clinical nephrology and there is a pressing need for novel therapeutics and biomarkers. Aberrant promoter CpG island methylation and subsequent transcriptional silencing of specific genes have emerged as contributors to progression of chronic kidney disease. Here, we report that transcriptional silencing of the Ras-GTP suppressor RASAL1 contributes causally to progression of kidney fibrosis and we identified that circulating methylated RASAL1 promoter DNA fragments in peripheral blood correspond with levels of intrarenal levels of RASAL1 promoter methylation and degree of fibrosis in kidney biopsies, enabling non-invasive longitudinal analysis of intrarenal CpG island methylation. Retrospective analysis of patients with hypertensive nephrosclerosis revealed that circulating methylated RASAL1 promoter DNA fragments in peripheral blood decrease with Dihydralazine treatment in patients with hypertensive nephrosclerosis, and provided evidence that low-dose Dihydralazine delays decline of excretory kidney function, whereas Dihydralazine at standard doses had no protective effect. We demonstrate that the protective effect of Dihydralazine is due to induction of endogenous Tet3/Tdg-mediated DNA-de-methylation activity reversing aberrant promoter CpG island methylation, while HIF1α induction at standard doses counterbalances its protective activity. We conclude that RASAL1 promoter methylation is a therapeutic target and a biomarker of renal fibrosis. Our study suggests that therapeutic use of low-dose Dihydralazine in patients with chronic kidney disease and fibrosis deserves further consideration.

Therapeutic Apheresis in Pediatric Patients with Acute CNS Inflammatory Demyelinating Disease

Background/Aims: In adults, plasma exchange (PE) has been shown to be an efficient treatment for severe relapses of acute inflammatory CNS demyelinating diseases. The aim of this study was to evaluate the safety and efficacy of this treatment in pediatric patients. Methods: We retrospectively analyzed a single-center cohort of pediatric patients with inflammatory CNS demyelinating disorders who underwent apheresis between 2007 and 2011. Results: Ten patients (mean age: 11.6 ± 3.4 years) with an acute relapse of multiple sclerosis (n = 5), neuromyelitis optica (n = 2) or acute disseminated encephalomyelitis were included. All received methylprednisolone prior to treatment with either PE (n = 5) or immunoadsorption (n = 5). Apheresis-related side effects were either self-limiting or easily managed. EDSS (Expanded Disability Status Scale) improved in 7 of 8 patients during apheresis and in all patients within 30 days from a median of 7.5 to 1 (p < 0.01). The visual acuity initially worsened during the procedure in 3 of 7 affected eyes (mean 0.09), but improved in all at follow-up (mean: 0.5; p = 0.008). Conclusions: Apheresis was well tolerated and associated with a favorable outcome in all pediatric patients similar to reports in adults.