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Human Erythropoietin (human + erythropoietin)
Kinds of Human Erythropoietin Selected AbstractsNOVEL ERYTHROPOIESIS STIMULATING PROTEIN (DARBEPOIETIN ALPHA) CORRECTS ANAEMIA OF EARLY CHRONIC KIDNEY DISEASE (CKD) AT A REDUCED DOSE FREQUENCY COMPARED WITH RECOMBINANT HUMAN ERYTHROPOIETIN (rHuEPO)NEPHROLOGY, Issue 1 2002Johnson Dw [source] Purification and characterization of recombinant human erythropoietin from milk of transgenic pigsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2009Eun Gyo Lee Abstract BACKGROUND: Human erythropoietin (hEPO), a hydrophobic acidic glycoprotein responsible for the regulation of red blood cell production in mammals, is used for the treatment of anemia. In general, the purification of transgenic animal-derived therapeutic proteins is not easy due to their low titer concentrations and abundant contaminant proteins. For the first time, here the purification and characterization of rhEPO from the milk of transgenic pigs are described. RESULTS: The rhEPO was purified by heparin chromatography, reverse-phase chromatography, and gel filtration chromatography, resulting in a 16.5% yield and > 98% purity. The rhEPO purified from the milk of transgenic pigs contained less acidic isoforms and was underglycosylated in contrast to CHO-derived rhEPO. Cell proliferation of the F-36/EPO-dependent cell line was proportional to the dose of transgenic pig-derived rhEPO. CONCLUSION: Transgenic pig-derived rhEPO with high purity was achieved after three-step chromatography following two-step precipitation. The transgenic pig-derived rhEPO was demonstrated to have comparable potency with CHO-derived rhEPO. Transgenic pig-derived rhEPO may not be therapeutically feasible because of different glycosylation, and thus further studies are required to elucidate the effect of this aberrant glycosylation on the biological activity and stability in vivo. Copyright © 2008 Society of Chemical Industry [source] Glycoform characterization of erythropoietin combining glycan and intact protein analysis by capillary electrophoresis , electrospray , time-of-flight mass spectrometryELECTROPHORESIS, Issue 13 2006Elvira Balaguer Abstract Glycosylation of recombinant human erythropoietin (rHuEPO) is a post-translational process that alters biological activity, solubility and lifetime of the glycoprotein in blood, and strongly depends on the type of cell and the cell culture conditions. A fast and simple method providing extensive carbohydrate information about the glycans present in rHuEPO and other glycoproteins is needed in order to improve current methods in drug development or product quality control. Here, an improved method for intact rHuEPO glycoform characterization by CZE-ESI-TOF MS has been developed using a novel capillary coating and compared to a previous study. Both methods allow a fast separation in combination with accurate mass characterization of the single protein isoforms. The novel dynamic coating provides a separation at an EOF close to zero, enabling better separation. This results in an improved mass spectrometric resolution and the detection of minor isoforms. In order to assign an unequivocal carbohydrate composition to every intact glycoform, a CZE-ESI-MS separation method for enzymatically released underivatized N -glycans has been developed. The TOF,MS allows the correct identification of the glycans due to its high mass accuracy and resolution. Therefore, glycan modifications such as acetylation, oxidation, sulfation and even the exchange of OH by NH2 are successfully characterized. Information of the protein-backbone molecular mass has been combined with results from peptide analysis (revealing information about O -glycosylation) and from the glycan analysis, including the detection of as yet undescribed glycans containing four antennae and five sialic acids. This allows an unequivocal assignment of an overall glycosylation composition to the molecular masses obtained for the intact rHuEPO glycoforms. [source] Improvement in quality of life for cancer patients treated with epoetin alfaEUROPEAN JOURNAL OF CANCER CARE, Issue 3 2001S.E. Libretto PHD BSC MIBIOL CBIOL Anaemia is a common complication of cancer and cancer therapies, and fatigue is one of the most common symptoms of anaemia, disrupting functional performance and reducing overall quality of life. The positive effects of treating renal patients with recombinant human erythropoietin are well documented. This case report series details the specific effects of fatigue on individual patients with cancer and their way of life, and describes their significant improvement in lifestyle following the reversal of anaemia using recombinant human erythropoietin, epoetin alfa. [source] Carbamylated erythropoietin increases frataxin independent from the erythropoietin receptorEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2010Brigitte Sturm Eur J Clin Invest 2010; 40 (6): 561,565 Abstract Background, Friedreich's ataxia (FRDA) is a neurodegenerative disorder caused by decreased expression of the mitochondrial protein frataxin. Recently we showed in a clinical pilot study in Friedreich's ataxia patients that recombinant human erythropoietin (rhuEPO) significantly increases frataxin-expression. In this in vitro study, we investigated the role of the erythropoietin receptor (EPO-R) in the frataxin increasing effect of rhuEPO and if nonerythropoietic carbamylated erythropoietin (CEPO), which cannot bind to the classical EPO-R increases frataxin expression. Materials and methods, In our experiments human erythroleukaemic K562 cells (+ EPO-R), human monocytic leukemia THP-1 cells (, EPO-R) and isolated primary lymphocytes from healthy control and FRDA patients were incubated with different concentrations of rhuEPO or CEPO. Frataxin-expression was detected by an electrochemical luminescence immunoassay (based on the principle of an ELISA). Results, We show that rhuEPO increases frataxin-expression in K562 cells (expressing EPO-R) as well as in THP-1 cells (without EPO-R expression). These results were confirmed by the finding that CEPO, which cannot bind to the classical EPO-R increased frataxin expression in the same concentration range as rhuEPO. In addition, we show that both EPO derivatives significantly increase frataxin-expression in vitro in control and Friedreich's ataxia patients primary lymphocytes. Conclusion, Our results provide a scientific basis for further studies examining the effectiveness of nonerythropoietic derivatives of erythropoietin for the treatment of Friedreich's ataxia patients. [source] Recombinant human erythropoietin suppresses symptom onset and progression of G93A-SOD1 mouse model of ALS by preventing motor neuron death and inflammationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Seong-Ho Koh Abstract Multifactorial pathogenic mechanisms, including inflammation, attenuated survival signals and enhanced death signals, are involved in amyotrophic lateral sclerosis (ALS). Erythropoietin (EPO) has recently been highlighted as a cytokine with various potent neuroprotective effects, including reduction of inflammation, enhancement of survival signals and prevention of neuronal cell death. This study was undertaken to evaluate the effect of recombinant human EPO (rhEPO) on ALS model mice. We treated 96 ALS model mice with vehicle only, or 1, 2.5 or 5 iµ of rhEPO/g of mouse once every other week after they were 60 days old. The treatment significantly prolonged symptom onset and life span, preserved more motor neurons, enhanced survival signals, and attenuated inflammatory signals in a dose-dependent manner. These data suggest that treatment with rhEPO represents a potential therapeutic strategy for ALS. [source] Erythropoietin reduces Schwann cell TNF-,, Wallerian degeneration and pain-related behaviors after peripheral nerve injuryEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2006W. Marie Campana Abstract Chronic sciatic nerve constriction injury (CCI) induces Wallerian degeneration and exaggerated pain-like behaviors. These effects are mediated in large part by pro-inflammatory cytokines, such as tumor necrosis factor alpha (TNF-,). In this study, we demonstrate that systemically administered recombinant human erythropoietin (rhEpo) facilitates recovery from chronic neuropathic pain associated with CCI in rats. Because TNF-, has been implicated in the development of pain-related behaviors, we measured TNF-, mRNA at the nerve injury site. Systemically or locally administered rhEpo decreased TNF-, mRNA, compared with that observed in untreated animals. RhEpo also significantly (P < 0.05) decreased axonal degeneration. Immunohistochemistry of CCI nerve showed abundant TNF-, in Schwann cells, axoplasm and macrophages. In rhEpo-treated animals, TNF-, immunopositivity was decreased selectively in Schwann cells. These results suggest a model in which rhEpo counteracts the effects of TNF-, in CCI by blocking expression of TNF-, in Schwann cells. To further test this model, we studied primary Schwann cell cultures. RhEpo inhibited TNF-, expression in response to lipopolysaccharide, supporting the conclusions of our in vivo CCI experiments. In addition, rhEpo directly counteracted Schwann cell death induced by exogenously added TNF-,in vitro. These results indicated that rhEpo regulates TNF-, by multiple mechanisms; rhEpo regulates TNF-, mRNA expression by Schwann cells but also may directly counteract TNF-, signaling pathways that lead to injury, chronic pain and/or death. [source] Effect of recombinant human erythropoietin on insulin resistance in hemodialysis patientsHEMODIALYSIS INTERNATIONAL, Issue 3 2009Essam KHEDR Abstract Insulin resistance is a characteristic feature of uremia. Insulin resistance and concomitant hyperinsulinemia are present irrespective of the type of renal disease. Treatment with recombinant human erythropoietin (rHuEPO) was said to be associated with improvement in insulin sensitivity in uremic patients. The aim of this study was to compare insulin resistance in adult uremic hemodialysis (HD) patients including diabetic patients treated with or without rHuEPO. A total of 59 HD patients were studied, patients were divided into 2 groups of subjects: 30 HD patients on regular rHuEPO treatment (group A), and 29 HD patients not receiving rHuEPO (group B) diabetic patients were not excluded. Full medical history and clinical examination, hematological parameters, lipid profile, serum albumin, parathyroid horomone, Kt/V, fasting glucose, and insulin levels were measured in all subjects. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was used to compare insulin resistance. The results of this study showed that the mean insulin level of HD patients treated with rHuEPO (group A) (17.5 ± 10.6 ,U/mL) was significantly lower than patients without rHuEPO (group B) (28.8 ± 7.7 ,U/mL), (P<0.001). Homeostasis Model Assessment of Insulin Resistance levels in group A were significantly lower than in group B (3.8 ± 2.97, 7.98 ± 4.9, respectively, P<0.001). Insulin resistance reflected by HOMA-IR levels among diabetic patients in group A was significantly lower than among diabetic patients in group B (3.9 ± 3.2, 9.4 ± 7.2, respectively, P<0.001). Also, HOMA-IR levels among nondiabetic patients in group A were significantly lower than among nondiabetic patients in group B (3.7 ± 2.85, 6.9 ± 1.43, respectively, P<0.01). We found a statistically significant negative correlation between duration of erythropoietin treatment, fasting blood glucose, insulin levels, and insulin resistance (r=,0.62, ,0.71, and ,0.57, P<0.001). Patients treated with rHuEPO showed less insulin resistance compared with patients not treated with rHuEPO in diabetic and nondiabetic patients and, duration of erythropoietin treatment is negatively correlated with insulin levels and insulin resistance in HD patients. [source] Effect of improvement in anemia on electroneurophysiological markers (P300) of cognitive dysfunction in chronic kidney diseaseHEMODIALYSIS INTERNATIONAL, Issue 3 2006Narinder P. SINGH Abstract Our aim is to study the effect of improvement in anemia on event-related potentials (ERPs; P300) as markers of cognitive dysfunction in predialysis and dialysis patients of chronic kidney disease (CKD). Thirty anemic patients of CKD (hemoglobin [Hb]<9 g%), 15 in the predialysis group (Group A), and 15 patients on biweekly hemodialysis (Group B) were recruited for the study. Patients of uremic encephalopathy, dyselectrolytemia, and those with hearing problems were excluded. Both groups were given recombinant human erythropoietin (rhuEPO) 100 IU/kg biweekly for 6 weeks by the subcutaneous route. No intervention was performed in the third control group (Group C), which consisted of 30 normal healthy volunteers. The improvement in Hb was assessed every 2 weeks, and the amplitude and latency of the P300 component of the ERPs were studied before initiating treatment and after 6 weeks of rhuEPO administration. There was a significant increase in Hb in both the study groups without any significant alteration in kidney functions. A significant reduction in P300 latency was noted in both the study groups after intervention. Similarly, the amplitude of P300 also increased in both study groups, but attained statistical significance for the dialysis group only. No significant changes were observed in the control group. Administration of EPO in patients of anemia with CKD resulted in a significant improvement in the electrophysiological markers of cognitive function in the form of increased amplitudes and decreased latencies of P300 in both predialysis and dialysis patients. [source] Correction of an anemia in patients with a terminal stage chronic renal insufficiency on haemodialysisHEMODIALYSIS INTERNATIONAL, Issue 1 2005R.Z. Ismagilov One of the basic symptoms of a terminal stage chronic renal insufficiency is anemia. From everything, used methods of correction of an anemia, it is considered the most effective application of preparations recombinant human erythropoietin (r-Hu EPO). Since 1994 in the Scientific Centre of Surgery begins application r-Hu EPO. Application r-Hu EPO in patients with a terminal stage chronic renal insufficiency in 90,95% of cases had a positive effect, but 5,10% of patients have intolerance to erythropoietin, that has induced to search of new effective methods of correction of anemia. During research were determined quantity erythrocytes, hemoglobin, reticulocyte in peripheral blood and acid-alkaline condition of blood. All hematology parameters were defined at the beginning of treatment, over 5 day and for 15 day of stimulation of a bone marrow. For 15 days after stimulation of a bone marrow by the laser there was an authentic increase of quantity erythrocyte, hemoglobin, hematocrit. The initial contents erythrocytes made 2.22 ± 0.1 10 × 12, hemoglobin 67.7 ± 3.2 g/l and hematocrit 18.2 ± 1.2%. During treatment by the laser parameters erythrocytes have increased up to 2.9 ± 0.8 10 × 12, hemoglobin up to 89.6 ± 2.9 g/l and hematocrit up to 28.2 ± 1.3%(P < 0,005). Hematology parameters in blood of control group authentically have not changed. [source] Intravenous iron attenuates postvaccination anti-HBsAg titres after quadruple hepatitis B vaccination in dialysis patients with erythropoietin therapyINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 3 2009J.-H. Liu Summary Background:, Anaemia in patients with end-stage renal disease (ESRD) is commonly treated with recombinant human erythropoietin (rHuEPO), often in combination with an adjuvant iron supplement. There is much evidence that rHuEPO can influence the immune response by its effect on lymphocytes. Also, iron catalyses the formation of radicals and increases the risk of major infections by negatively affecting the immune system. The relationship between antibodies to hepatitis B surface antigen (anti-HBsAg) responsiveness after hepatitis B vaccination and rHuEPO/adjuvant iron supplementation has not been reported before. Aim:, To determine the effects of subcutaneous erythropoietin and intravenous (i.v.) iron therapy on the responsiveness of anti-HBsAg after quadruple hepatitis B vaccination among ESRD patients. Methods:, Retrospective medical records were reviewed in a hospital with a tertiary teaching facility. Eighty-three ESRD patients, including 51 who underwent haemodialysis and 32 who underwent peritoneal dialysis therapy, received a quadruple recombinant hepatitis B vaccine. We investigated anti-HBsAg titres in those patients who either received rHuEPO alone (n = 50) or rHuEPO in combination with i.v. iron (n = 33). Results:, We found that the postvaccination anti-HBsAg titre was significantly lower in the rHuEPO plus i.v. iron group when compared with the group with rHuEPO alone (p < 0.05). The increment of anti-HBsAg between the initial month and the seventh month was positively correlated with therapeutic rHuEPO dosages in the group with rHuEPO alone (r = 0.303, p = 0.033). This relationship was not present in the rHuEPO with i.v. iron group (r = ,0.289, p = 0.229). Conclusions:, The levels of anti-HBsAg after hepatitis B vaccination are positively correlated with the dose of rHuEPO treatment during the vaccinated period among ESRD patients without i.v. iron supplementation. Also, i.v. iron negatively impacts the responsiveness of anti-HBsAg titre after hepatitis B vaccination in ESRD patients who have undergone rHuEPO therapy. [source] Cloning and molecular dissection of the 8.8 kb pig uroplakin II promoter using transgenic mice and RT4 cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2006Deug-Nam Kwon Abstract Uroplakin II (UPII) gene expression is highly tissue and cell specific, with mRNA present in the suprabasal cell layers of the bladder and urethra. Previous reports described the mouse UPII (mUPII) promoter as primarily urothelium selective. However, ectopic expression of a transgene under the 3.6 kb mUPII promoter was also detected in brain, kidney, and testis in some transgenic mouse lines. Here, we have cloned an 8.8 kb pig UPII (pUPII) promoter region and investigated which cells within the bladder and urethra express a transgene consisting of the pUPII promoter fused to human erythropoietin (hEPO) or a luciferase gene. pUPII-luciferase expression vectors with various deletions of the promoter region were introduced into mouse fibroblast (NIH3T3), Chinese hamster ovary (CHO), and human bladder transitional carcinoma (RT4). A 2.1 kb pUPII promoter fragment displayed high levels of luciferase activity in transiently transfected RT4 cells, whereas the 8.8 kb pUPII promoter region displayed only low levels of activity. The pUPII-hEPO expression vector was injected into the pronucleus of zygotes to make transgenic mice. To elucidate the in vivo molecular mechanisms controlling the tissue- and cell-specific expression of the pUPII promoter gene, transgenic mice containing 2.1 and 8.8 kb pUPII promoter fragments linked to the genomic hEPO gene were generated. An erythropoietin (EPO) assay showed that all nine transgenic lines carrying the 8.8 kb construct expressed recombinant human erythropoietin (rhEPO) only in their urethra and bladder, whereas two transgenic lines carrying the 2.1 kb pUPII promoter displayed hEPO expression in several organs including bladder, kidney, spleen, heart, and brain. These studies demonstrate that the 2.1 kb promoter contains the DNA elements necessary for high levels of expression, but lacks critical sequences necessary for tissue-specific expression. We compared binding sites in the 2.1 and 8.8 kb promoter sequences and found five peroxisome proliferator responsive elements (PPREs) in the 8.8 kb promoter. Our data demonstrated that proliferator-activated receptor (PPAR)-, activator treatment in RT4 cells induced the elevated expression of hEPO mRNA under the control of the 8.8 kb pUPII promoter, but not the 2.1 kb promoter. Collectively, our data suggested that all the major trans-regulatory elements required for bladder- and urethra-specific transcription are located in the 8.8 kb upstream region and that it may enhance tissue-specific protein production and be of interest to clinicians who are searching for therapeutic modalities with high efficacy and low toxicity. J. Cell. Biochem. 99: 462,477, 2006. © 2006 Wiley-Liss, Inc. [source] Purification and characterization of recombinant human erythropoietin from milk of transgenic pigsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2009Eun Gyo Lee Abstract BACKGROUND: Human erythropoietin (hEPO), a hydrophobic acidic glycoprotein responsible for the regulation of red blood cell production in mammals, is used for the treatment of anemia. In general, the purification of transgenic animal-derived therapeutic proteins is not easy due to their low titer concentrations and abundant contaminant proteins. For the first time, here the purification and characterization of rhEPO from the milk of transgenic pigs are described. RESULTS: The rhEPO was purified by heparin chromatography, reverse-phase chromatography, and gel filtration chromatography, resulting in a 16.5% yield and > 98% purity. The rhEPO purified from the milk of transgenic pigs contained less acidic isoforms and was underglycosylated in contrast to CHO-derived rhEPO. Cell proliferation of the F-36/EPO-dependent cell line was proportional to the dose of transgenic pig-derived rhEPO. CONCLUSION: Transgenic pig-derived rhEPO with high purity was achieved after three-step chromatography following two-step precipitation. The transgenic pig-derived rhEPO was demonstrated to have comparable potency with CHO-derived rhEPO. Transgenic pig-derived rhEPO may not be therapeutically feasible because of different glycosylation, and thus further studies are required to elucidate the effect of this aberrant glycosylation on the biological activity and stability in vivo. Copyright © 2008 Society of Chemical Industry [source] Use of exogenous erythropoietin in critically ill patientsJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 3 2004R. MacLaren PharmD Summary Objective:, Review the literature regarding the use of recombinant human erythropoietin (rHuEPO) to prevent red blood cell (RBC) transfusion in critically ill patients. Data sources:, A computerized search of MEDLINE and EMBASE from 1966 through June 2003 was conducted using the terms erythropoietin, anemia, hemoglobin, critical care, intensive care, surgery, trauma, burn, and transfusion. References of selected articles were reviewed. A manual search of critical care, surgery, trauma, burn, hematology, and pharmacy journals was conducted to identify relevant abstracts. Results:, Six randomized studies have evaluated exogenous administration of erythropoietin to prevent RBC transfusions in critically ill patients. Studies vary with respect to rHuEPO dosage regimens, dose of concurrently administered iron, patient characteristics, and transfusion thresholds. Administration of rHuEPO rapidly produces erythropoiesis to reduce the need for RBC transfusions. The largest study conducted to date used weekly rHuEPO administration and found a modest decrease in transfusion requirements although the time to first transfusion was delayed. Reduced intensive care unit (ICU) length of stay (LOS) was shown in only one study of surgical/trauma patients. Reduced LOS after ICU discharge was found in another study of severely ill patients (APACHE II score >22). Other clinical outcomes were not altered by rHuEPO use. No adverse events were associated with rHuEPO use although studies were not designed to evaluate safety. Conclusions:, rHuEPO reduces the need for transfusions. A cost-effectiveness analysis of rHuEPO for this indication is needed. Defining an optimal dosage regimen, identifying patients most likely to respond to rHuEPO, and determining risk factors for ICU associated anaemia would provide information for appropriate rHuEPO utilization. [source] Glycoengineering: The effect of glycosylation on the properties of therapeutic proteinsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 8 2005Angus M. Sinclair Abstract Therapeutic proteins have revolutionized the treatment of many diseases but low activity or rapid clearance limits their utility. New approaches have been taken to design drugs with enhanced in vivo activity and half-life to reduce injection frequency, increase convenience, and improve patient compliance. One recently used approach is glycoengineering, changing protein-associated carbohydrate to alter pharmacokinetic properties of proteins. This technology has been applied to erythropoietin and resulted in the discovery of darbepoetin alfa (DA), a hyperglycosylated analogue of erythropoietin that contains two additional N-linked carbohydrates, a threefold increase in serum half-life and increased in vivo activity compared to recombinant human erythropoietin (rHuEPO). The increased serum half-life allows for less frequent dosing to maintain target hemoglobin levels in anemic patients. Carbohydrates on DA and other molecules can also increase molecular stability, solubility, increase in vivo biological activity, and reduce immunogenicity. These properties are discussed. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:1626,1635, 2005 [source] Clinical Efficacy and Safety of Recombinant Canine Erythropoietin in Dogs with Anemia of Chronic Renal Failure and Dogs with Recombinant Human Erythropoietin-Induced Red Cell AplasiaJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2004John F. Randolph The efficacy and safety of recombinant canine erythropoietin (rcEPO) therapy was evaluated in 19 dogs with anemia of chronic renal failure (group 1) and 6 dogs with chronic renal failure and recombinant human erythropoietin (rhEPO)-induced red cell aplasia (group 2). Hematocrit (Hct) and absolute reticulocyte count (ARC) were monitored weekly for the first 8 weeks, CBC (including ARC) and serum iron profiles were evaluated monthly, and serum biochemical analyses were performed every 2 months for 6 (group 2) to 12 (group 1) months. For group 1 dogs, median Hct and ARC increased significantly during the 1st week of rcEPO treatment, and median Hct was sustained at >35% after week 5. In contrast, median Hct and ARC for group 2 did not change significantly with rcEPO treatment, even with doses greater than those used in group 1. Nevertheless, 2 (33%) of the 6 dogs in group 2 developed erythroid hyperplasia, reticulocytosis, and increases in Hct with rcEPO treatment. Although median systolic blood pressure did not change significantly in either group, 5 dogs developed systolic blood pressures a 180 mm Hg during the study. Appetite and energy level improved in most group 1 dogs with increases in Hct. Recombinant cEPO stimulated erythrocyte production in dogs with nonregenerative anemia secondary to chronic renal failure without causing the profound erythroid hypoplasia that can occur in rhEPO-treated dogs. Unfortunately, rcEPO was not as effective in restoring erythrocyte production in dogs that had previously developed rhEPO-induced red cell aplasia. [source] Definition and management of anemia in patients infected with hepatitis C virusLIVER INTERNATIONAL, Issue 4 2006John G. McHutchison Abstract: Chronic infection with hepatitis C virus (HCV) can progress to cirrhosis, hepatocellular carcinoma, and end-stage liver disease. The current best treatment for HCV infection is combination therapy with pegylated interferon and ribavirin. Although this regimen produces sustained virologic responses (SVRs) in approximately 50% of patients, it can be associated with a potentially dose-limiting hemolytic anemia. Hemoglobin concentrations decrease mainly as a result of ribavirin-induced hemolysis, and this anemia can be problematic in patients with HCV infection, especially those who have comorbid renal or cardiovascular disorders. In general, anemia can increase the risk of morbidity and mortality, and may have negative effects on cerebral function and quality of life. Although ribavirin-associated anemia can be reversed by dose reduction or discontinuation, this approach compromises outcomes by significantly decreasing SVR rates. Recombinant human erythropoietin has been used to manage ribavirin-associated anemia but has other potential disadvantages. Viramidine, a liver-targeting prodrug of ribavirin, has the potential to maintain the virologic efficacy of ribavirin while decreasing the risk of hemolytic anemia in patients with chronic hepatitis C. [source] Darbepoetin alfa administered monthly maintains haemoglobin concentrations in patients with chronic kidney disease not receiving dialysis: A multicentre, open-label, Australian studyNEPHROLOGY, Issue 1 2007ALEX DISNEY SUMMARY: Aim: Darbepoetin alfa, an erythropoiesis-stimulating protein, has a longer serum half-life than recombinant human erythropoietin, allowing less-frequent administration. This study aimed to demonstrate that once-monthly (QM) darbepoetin alfa administration would maintain haemoglobin (Hb) concentrations in subjects with chronic kidney disease (CKD) not receiving dialysis who had previously been administered darbepoetin alfa every 2 weeks (Q2W). Methods: This was a multicentre study in which subjects with CKD receiving stable Q2W darbepoetin alfa doses and with stable Hb (100,130 g/L) were started on QM darbepoetin alfa dosing. The initial QM darbepoetin alfa dose was equivalent to the cumulative darbepoetin alfa dose administered during the month preceding enrolment. Darbepoetin alfa doses were titrated to maintain Hb concentrations between 100 and 130 g/L. The primary endpoint was the proportion of subjects maintaining mean Hb 0e; 100 g/L during the evaluation period (weeks 21,33). Results: Sixty-six subjects were enrolled in the study and all received at least one dose of darbepoetin alfa; 55 (83%) had mean Hb 0e; 100 g/L during evaluation. Mean (SD) Hb concentrations at baseline and during the evaluation period were 119 (8.7) g/L and 114 (9.8) g/L, respectively. The median QM darbepoetin alfa dose at baseline and during the evaluation period was 80 ,g. Darbepoetin alfa was considered to be well-tolerated. Conclusion: Patients with CKD not receiving dialysis who are receiving darbepoetin alfa Q2W can be safely and effectively extended to darbepoetin alfa QM. Dosing QM may simplify anaemia management for patients and health-care providers. [source] Erythropoietin attenuates white matter damage, proinflammatory cytokine and chemokine induction in developing rat brain after intra-uterine infectionNEUROPATHOLOGY, Issue 5 2009Ying Shen To investigate the possible ameliorating effect of recombinant human erythropoietin (rhEPO) on white matter damage, pro-inflammatory cytokine and chemokine induction in developing rat brain after intra-uterine Escherichia coli infection. E. coli was inoculated into uterine cervix of the time-pregnant rats and the control was injected with normal saline. Following maternal E. coli inoculation, the pups received a single intraperitoneal injection of rhEPO at a dose of 5000 IU/kg body weight immediately after birth. Immunohistochemical staining and Western blot analysis for 2,, 3,-cyclic nucleotide 3,-phosphodiesterase (CNPase), neurofilament (NF) and glial fibrillary acidic protein (GFAP) were performed to assess white matter damage in pup brains at post-natal day 1 (P1), P3 and P7. Pro-inflammatory cytokines and chemokines were detected by real-time quantitative RT-PCR at the mRNA levels to evaluate the inflammatory response in pup brains at P1, P3 and P7. A single dose of rhEPO treatment (5000 IU/kg body weight) attenuated white matter damage in developing rat brain after intra-uterine E. coli infection. The protein levels of CNPase and NF in pup brains at P7 significantly increased after post-natal rhEPO treatment as compared with the intra-uterine E. coli -treated group. Also, post-natal rhEPO injection markedly attenuated the intra-uterine E. coli infection-induced increases in GFAP protein expression and the mRNA levels of pro-inflammatory cytokines and chemokines. Post-natal EPO administration as a single dose may exert a neuroprotective effect on white matter damage by reducing pro-inflammatory cytokine and chemokine induction in developing rat brain after intra-uterine E. coli infection. [source] Early epoetin alfa treatment in children with solid tumors,PEDIATRIC BLOOD & CANCER, Issue 4 2002Andreas Zoubek MD Abstract Background Combination chemotherapy is often used for long periods in children with solid malignancies, leading to anemia and necessitating intervention with red blood cell (RBC) transfusions. Transfusions, however, are associated with a variety of adverse events and risks. Recombinant human erythropoietin (rHuEPO, epoetin alfa) has been shown to reduce the need for transfusions and to ameliorate the symptoms of anemia in adults, but few studies have been conducted thus far in pediatric patients. Procedure Thirty-seven children with solid tumors receiving treatment with platinum- or nonplatinum-based chemotherapy were treated with epoetin alfa and supplemental iron in a single-center, open-label, 28-week, case-control study. Results Epoetin alfa significantly reduced the need for RBC (P,=,0.007) and platelet (P,=,0.01) transfusions, and prolonged the time to first RBC transfusion (P,=,0.0004) as compared to the control group. Moreover, epoetin alfa was effective in maintaining mean hemoglobin levels during the course of the study, whereas they declined below baseline after week 9 in the control group. Conclusions Epoetin alfa is effective and safe in reducing transfusion requirements and maintaining adequate hemoglobin levels in children with solid tumors undergoing combination chemotherapy. Med Pediatr Oncol 2002; 39:459,462. © 2002 Wiley-Liss, Inc. [source] Recombinant human erythropoietin in pediatric oncology: A review,PEDIATRIC BLOOD & CANCER, Issue 4 2002James Feusner MD Abstract Background Numerous reports on recombinant human erythropoietin (rHuEPO, epoetin alfa) treatment of cancer-related anemia in adult patients have been published to date. These have shown that epoetin increases hemoglobin levels, significantly ameliorates symptoms of anemia, and improves adult patients' quality of life. Unfortunately, less is known about the impact of epoetin on anemia in pediatric cancer patients. Procedure It is the objective of this review to summarize and analyze data of clinical trials of epoetin treatment of anemia in pediatric cancer patients. Results A total of 15 studies were reviewed; eight were considered for detailed analysis and demonstrated important variabilities in study methods. Four of the eight were controlled, randomized trials and four were open label. Conclusions These studies suggested an overall beneficial effect of epoetin alfa for treating anemia in children with cancer. Three large, multicenter clinical trials of the efficacy and safety of epoetin alfa in anemic children with cancer are currently underway, one in Europe and two in North America. Med Pediatr Oncol 2002; 39:463,468. © 2002 Wiley-Liss, Inc. [source] Erythropoietin improves neurodevelopmental outcome of extremely preterm infantsANNALS OF NEUROLOGY, Issue 5 2010Achim-Peter Neubauer MD Objective Erythropoietin has been reported to possess neuroprotective properties in animal studies. No previous studies have investigated the neurodevelopmental outcome of extremely low birth weight (ELBW) infants treated with recombinant human erythropoietin (rEpo) and evaluated it at school age. Methods Of 200 ELBW infants treated from 1993 to 1998, 171 (86%) survived, and 148 (87%) were followed up to the age of 10 to 13 years. The neurodevelopmental and school outcome of the ELBW infants receiving rEpo treatment for stimulation of erythropoiesis in the first weeks of life (n = 89) was compared to that of untreated children (n = 57). To test for a neuroprotective effect of erythropoietin therapy, analyses of variance (ANOVAs) were conducted with erythropoietin treatment and intraventricular hemorrhage (IVH) as independent variables and Hamburg-Wechsler Intelligence Test for Children-III (HAWIK-III) intelligence quotient (IQ) scores as dependent variables. Results The rEpo group scored significantly better than untreated children in the overall developmental assessment (55% vs 39% normally developed, p < 0.05) as well as in the psychological examination (mean composite HAWIK-III IQ score, 90.8 vs 81.3, p < 0.005). The results of ANOVAs show that these differences were ascribable to children with IVH. Whereas those children with IVH treated with rEpo scored significantly better than untreated children (52% vs 6% normally developed, composite HAWIK-III IQ score, 90.3 vs 67.0), treated and untreated children without IVH did not differ in their outcome. The treatment and control groups were comparable in perinatal parameters relevant to prognosis. Interpretation The results of our observational study confirm the hypothesis of a neuroprotective effect of rEpo in ELBW infants with IVH. This offers a promising preventative therapeutic option for the treatment of these high-risk infants. ANN NEUROL 2010;67:657,666 [source] Erythropoietin Receptor Is Expressed on Human Peripheral Blood T and B Lymphocytes and Monocytes and Is Modulated by Recombinant Human Erythropoietin TreatmentARTIFICIAL ORGANS, Issue 8 2010Katarzyna A. Lisowska Abstract Erythropoietin receptor (EPO-R) appears on the cell surface in the early stages of erythropoiesis. It has also been found on endothelial cells and polymorphonuclear leukocytes, suggesting erythropoietin (EPO) role beyond erythropoiesis itself. Earlier reports have shown that treatment with recombinant human erythropoietin (rhEPO) in chronic renal failure (CRF) patients improves interleukin-2 production and restores the T lymphocyte function. We decided to investigate possible expression of EPO-R on circulating peripheral blood lymphocytes and monocytes of CRF patients in order to assess the possibility of rhEPO direct action on these cells. Flow cytometry was used for detection and quantification of EPO-R, and reverse transcription polymerase chain reaction for detection of the EPO receptor mRNA. Our results show for the first time the existence of EPO-R on cell surface of human T and B lymphocytes and monocytes as well as at the transcriptional activity of the EPO-R gene in these cells, both in healthy and CRF individuals. We have also found significant differences between the numbers of EPO-R molecules on T and B lymphocytes of CRF patients not treated and treated with rhEPO and healthy control. Discovery of EPO-R expression on human lymphocytes suggests that EPO is probably able to directly modulate some signaling pathways important for these cells. [source] Recombinant Human Erythropoietin Treatment of Chronic Renal Failure Patients Normalizes Altered Phenotype and Proliferation of CD4-positive T LymphocytesARTIFICIAL ORGANS, Issue 3 2010Katarzyna A. Lisowska Abstract Patients with chronic renal failure (CRF) receive recombinant human erythropoietin (rhEPO) for the correction of anemia. However, rhEPO also has an immunomodulatory effect. Detailed changes of phenotype and function of CD4+ T lymphocytes in CRF patients receiving rhEPO have not been reported yet; their study may bring insight into understanding of this immunomodulatory action of rhEPO. Two groups of CRF patients were included into the study: those treated; and those not receiving rhEPO. The expression of activation markers on CD4+ lymphocytes was measured with flow cytometry, both ex vivo and in vitro. The kinetics of CD4+ T lymphocytes proliferation was calculated using a dividing cells tracing method and numerical approach. Significantly higher percentages of CD4+CD95+, CD4+HLA-DR+ cells, and lower percentages of CD4+CD69+ and CD4+CD28+ cells were observed in both rhEPO-treated and untreated patients when compared with healthy controls. Changes in the proportions of CD4+CD28+ and CD4+HLA-DR+ subpopulations were dependent on the type of rhEPO, being more pronounced for rhEPO,. CD4+ lymphocytes from untreated patients exhibited decreased expression of CD28 and CD69 after stimulation in vitro, whereas the expression of these antigens on lymphocytes of rhEPO-treated patients was similar to that observed in healthy controls. Fewer CD4+CD28+ T lymphocytes of untreated patients proliferated in vitro; these cells had longer G0,G1 time, which negatively correlated with surface expression of CD28. Our study confirms that rhEPO treatment normalizes activation parameters of CD4+ T lymphocytes and their proliferative capacity, which could explain earlier described immunomodulatory effects of rhEPO in patients suffering from CRF. [source] Use of Clinical Guidelines for Treatment of Anemia Among Hemodialysis PatientsARTIFICIAL ORGANS, Issue 2 2000Mae Thamer Abstract: Changing financial incentives have strongly influenced dosing patterns of recombinant human erythropoietin (rHuEPO) since its introduction in 1989. Although guidelines for prescribing rHuEPO exist, the extent to which they are adhered to is unknown. Using a retrospective cohort observational study design, the factors influencing the initial dosing of rHuEPO prescribed to 413 hemodialysis patients in 1994 were examined. Patient weight, the only recommended guideline, was not found to be a significant predictor of dosing of rHuEPO after controlling for selected patient demographic and clinical characteristics. The strongest predictor for initial rHuEPO dosing was hematocrit followed by White race (p < 0.05). Finally, each subsequent month was associated with a significantly larger initial rHuEPO dose, reflecting the general trend in increasing dose since 1991 (p < 0.001). In conclusion, despite the recent DOQI guidelines for treatment of anemia among persons with chronic renal failure, providers are not using patient weight as an independent criterion for determining dosing of rHuEPO. [source] Time-dependent clearance and hematological pharmacodynamics upon erythropoietin multiple dosing in ratsBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 5-6 2010Sihem Ait-Oudhia Abstract The pharmacokinetics (PK) and pharmacodynamics (PD) of recombinant human erythropoietin (rHuEPO) upon its repeated administrations were investigated. Two groups (A and B) of normal Wistar rats received rHuEPO intravenously at 450 or 1350,IU/kg thrice weekly for 2 and 6 weeks. PK studies were conducted following days 0 and 4 for group (A) and days 0, 17 and 28 for group (B), then, washout PK were assessed on days 11 and 36 for both groups. Reticulocytes (RET), red blood cells (RBC) and hemoglobin (Hb) were evaluated daily until day 14, then every 2 days until day 30 for group (A) and 59 for group (B). The total clearance CLTotal increased with the dose but decreased over time. Its decay reached 20% and 55% between the first and last full PK in both treatment arms. RET peaked on day 5 and were 77.6% and 87.3% higher than baselines for the two dosing regimen. Their nadirs occurred on days 22 and 55 and were 37.9% and 47.3% below normal values. Hb peaked on days 10 and 34 and was 28.9% and 38.6% above the baseline level, its nadirs occurred on days 25 and 57 and were 13.1% and 16% below baselines. Control animals showed stable baselines over the study but with moderate variability. In conclusion, rHuEPO exhibits a nonlinear PK with a time-dependent decrease of its CLTotal. During exposure, RET, RBC and Hb showed a tolerance effect. After exposure, the rebound was characterized for RET, RBC, but not Hb. Copyright © 2010 John Wiley & Sons, Ltd. [source] Comparative pharmacokinetics, safety, and tolerability after subcutaneous administration of recombinant human erythropoietin formulated with different stabilizersBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 6 2000Wing K. Cheung Abstract This report summarizes the results of two double-blind, single-center, randomized studies that used a two-period crossover design. The objective of these two studies was to compare the safety, tolerability, pharmacokinetics, and pain score at the subcutaneous (sc) injection site of a phosphate-buffered recombinant human erythropoietin (EPREX®, epoetin alfa, r-HuEPO) formulated with a new stabilizer (glycine and Polysorbate 80) with the commercially available EPREX® formulations, which uses human serum albumin (HSA) as the stabilizer. Twenty-four healthy male volunteers were enrolled in each of the two studies. In the first study, subjects received a single 150 IU/kg sc dose of r-HuEPO using the 2000 IU/mL (2K) phosphate-buffered formulation with or without the new stabilizer (12 subjects/group). In the second study, subjects received a single 750 IU/kg sc dose of r-HuEPO using the 40,000 IU/mL (40K) phosphate-buffered formulation with or without the new stabilizer (12 subjects/group). In each study, r-HuEPO was administered over two separate dosing periods, each separated with a 28-day washout period. There were no significant differences in AUC and Cmax for either strength of r-HuEPO formulated with or without the new stabilizer, indicating that the absorption and disposition characteristics of the two formulations were similar after sc administration. Both r-HuEPO strengths with and without the new stabilizer were safe and well tolerated; the safety and tolerability profiles of both formulations for each r-HuEPO concentration were comparable. There were no statistically significant differences in pain score for either strength of r-HuEPO with and without the new stabilizer. It was concluded that the two phosphate-buffered r-HuEPO concentrations formulated with and without the new stabilizer are pharmacokinetically equivalent. Copyright © 2000 John Wiley & Sons, Ltd. [source] Metabolic flux analysis for recombinant protein production by Pichia pastoris using dual carbon sources: Effects of methanol feeding rateBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2010Eda Çelik Abstract The intracellular metabolic fluxes through the central carbon pathways in the bioprocess for recombinant human erythropoietin (rHuEPO) production by Pichia pastoris (Mut+) were calculated to investigate the metabolic effects of dual carbon sources (methanol/sorbitol) and the methanol feed rate, and to obtain a deeper understanding of the regulatory circuitry of P. pastoris, using the established stoichiometry-based model containing 102 metabolites and 141 reaction fluxes. Four fed-batch operations with (MS-) and without (M-) sorbitol were performed at three different constant specific growth rates (h,1), and denoted as M-0.03, MS-0.02, MS-0.03, and MS-0.04. Considering the methanol consumption pathway, the M-0.03 and MS-0.02 conditions produced similar effects and had >85% of formaldehyde flux towards the assimilatory pathway. In contrast, the use of the dual carbon source condition generated a shift in metabolism towards the dissimilatory pathway that corresponded to the shift in dilution rate from MS-0.03 to MS-0.04, indicating that the methanol feed exceeded the metabolic requirements at the higher µ0. Comparing M-0.03 and MS-0.03 conditions, which had the same methanol feeding rates, sorbitol addition increased the rHuEPO synthetic flux 4.4-fold. The glycolysis, gluconeogenesis, and PPP pathways worked uninterruptedly only at MS-0.02 condition. PPP and TCA cycles worked with the highest disturbances at MS-0.04 condition, which shows the stress of increased feeding rates of methanol on cell metabolism. Biotechnol. Bioeng. 2010; 105: 317,329. © 2009 Wiley Periodicals, Inc. [source] Amino acid and manganese supplementation modulates the glycosylation state of erythropoietin in a CHO culture systemBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2007Christopher K. Crowell Abstract The manufacture of secreted proteins is complicated by the need for both high levels of expression and appropriate processing of the nascent polypeptide. For glycoproteins, such as erythropoietin (EPO), posttranslational processing involves the addition of oligosaccharide chains. We initially noted that a subset of the amino acids present in the cell culture media had become depleted by cellular metabolism during the last harvest cycle in our batch fed system and hypothesized that by supplementing these nutrients we would improve EPO yields. By increasing the concentration of these amino acids we increased recombinant human erythropoietin (rHuEPO) biosynthesis in the last harvest cycle as expected but, surprisingly, we also observed a large increase in the amount of rHuEPO with a relatively low sialic acid content. To understand the nature of this process we isolated and characterized the lower sialylated rHuEPO pool. Decreased sialylation correlated with an increase in N-linked carbohydrates missing terminal galactose moieties, suggesting that ,-1,4-galactosyltransferase may be rate limiting in our system. To test this hypothesis we supplemented our cultures with varying concentrations of manganese (Mn2+), a cofactor for ,-1,4-galactosyltransferase. Consistent with our hypothesis we found that Mn2+ addition improved galactosylation and greatly reduced the amount of rHuEPO in the lower sialylated fraction. Additionally, we found that Mn2+ addition increased carbohydrate site occupancy and narrowed carbohydrate branching to bi-antennary structures in these lower sialylated pools. Surprisingly Mn2+ only had this effect late in the culture process. These data indicate that the addition of Mn2+ has complex effects on stressed batch fed cultures. Biotechnol. Bioeng. 2007;96: 538,549. © 2006 Wiley Periodicals, Inc. [source] Enhancement of recombinant protein production in Chinese hamster ovary cells through anti-apoptosis engineering using 30Kc6 geneBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2006Shin Sik Choi Abstract It was previously reported that silkworm hemolymph (SH) inhibits apoptosis and increases the production of recombinant human erythropoietin (EPO) in Chinese hamster ovary (CHO) cells. The apoptosis-inhibiting component in SH is a member of 30K protein family. In this study, the CHO cell line producing EPO was manipulated genetically to express the 30Kc6 gene encoding a 30K protein in the hemolymph of the silkworm, Bombyx mori. The transient expression of 30Kc6 significantly suppressed the cell death induced by serum deprivation. A stable cell line expressing 30Kc6 with an anti-apoptotic property was established. The stable expression of 30Kc6 inhibited serum-deprivation-induced apoptosis and increased the cell density and EPO titer by 5- and 10-fold, respectively. The positive effects of the 30Kc6 expression on cell viability and productivity were due to the stable maintenance of the mitochondrial activity. The 30Kc6 expression efficiently suppressed the depolarization of the mitochondrial membrane and subsequently balanced the generation/consumption of ATP. The use of the 30Kc6 gene is expected to provide a new method of host cell engineering for improving the productivity of the recombinant protein. © 2006 Wiley Periodicals, Inc. 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