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Background&Objective: Decrease in production of erythropoietin has been noted as one of the main factors causing anemia in ESRD patients, and administration of recombinant human erythropoietin (rhEPO) has been used to correct the anemia. Iron deficiency, including functional iron deficiency, limits the efficacy of rhEPO therapy in ESRD patients. This study examined the effects of maintenance intravenous iron sucrose (Venofer) on haemoglobin level and, optimization of erythropoietin therapy. Materials&Methods: Forty eight haemodialysis patients with haemoglobin level<9 gr/dl who were dialyzed three times weekly went under the study. Two thousands units of rhEPO were given subcutaneously at the end of each dialysis for seven weeks. At the end of the seventh week, those with haemoglobin level<9 gr/dl and with ferritin level <200 ng/dl (29 patients) were chosen for intravenous administration of 100 mg Venfor during the next five consecutive haemodialysis while maintaining the rhEPO dose at 2000 units with each dialysis. A week after the last dose of Venofer, haemoglobin and serum ferritin were determined. Results: Average haemoglobin level among the patients before administration of rhEPO was 7.5 gr/dl. After seven weeks of subcutaneous rhEPO at 2000 units with each haemodialysis, the average haemoglobin level raised to 8.5 gr/dl. The effect of maintenance IV Venofer was an increase in average haemoglobin level to 10.4 gr/dl. The same effect was seen on the ferritin level. The ferritin level of 131 ng/dl increased to 237 ng/dl a week after last dose of IV venofer. Conclusion: Intravenous (IV) iron improves haemoglobin response and, thus, optimizes rhEPO therapy.

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Background and Objective: Human erythropoietin (EPO) is a glycosylated hormone with molecular weight of about 40 KDa which is synthesized in kidneys and plays an important role in proliferation and differentiation of erythrocytes.This study was done to assess and analyze the expression of recombinant EPO in Leishmania tarentolae host. Method: In this descriptive study, the EPO gene was codoned , optimized with bioinformatics database prior to be synthesized. It was cleaved by KpnIandXbaI enzymes and cloned into pLEXSY expression vector. The constructed expression cassette was transfected into Leishmania tarentolae through electroporaton method. Identification and confirmation of transfected colonies was performed using PCR expression diagnostic primers and EPO specific primers. Induction of the cloned gene was done with tetracycline. The expression in induced strains was analyzed by SDS-PAGE and western blotting techniques. The amount of recombinant protein was quantified by ELISA method. Confirmation of cloning and EPO expression cassette was carried out through genetic engineering procedures. Results: Expression analysis of transfected parasitic strain with SDS-PAGE and western blotting confirmed gene integration into chromosomal of host as well as expression. The optimal conditions for expression were found to be 10μg of tetracycline and 72h induction time. Molecular weight of expressed protein estimated to be 40 KDa and expression level was determined to be 12.4 mg/l which was equal to 1% of total protein mass. Conclusion: EPO expression cassette for cloning and expression in Leishmania tarentolae was designed and protein of interest was successfully induced and identified Leishmania tarentolae can be used as a suitable host for production of recombinant EPO and this technology has a potential for localization.