Abstract
Recombinant human erythropoietin (rEPO) was administered to 25 maintenance hemodialysis patients with severe anemia (hemoglobin level 6.22±0.11g/dl: mean±SE) at a dose of 3, 000U, three times a week for eight consecutive weeks, to evaluate the clinical effects. In addition, immunological response was also observed before and after rEPO administration to investigate the effects of this agent on the immune system.
A significant increase in reticulocyte count began to be observed from one week after the first administration, while significant increases in red blood cell count, hemoglobin level and hematocrit value began to be observed two weeks after administration. The increases in these values continued thereafter. The hemoglobin level 8 weeks after administration reached 8.22±0.18g/dl (18 cases). In association with the augmented hematopoietic effects, marked decreases in transfusion volume as well as improvement or disappearance of subjective and objective symptoms were noted. Moreover, decreases in the cardiothoratic ratio were also observed. With the exception of the patients that withdrew, improvement of anemia was observed in all cases.
The effects of rEPO on immunological parameters included a significant increase in the area responding in the skin test with purified protein derivative (PPD) after administration of the agent. This suggested improvement in cellular immune functions. In addition, there was a significant increase in the lymphocyte subset OKT3, while there were significant decreases in B-lymphocyte count and the immunoglobulin A (IgA) level. However, no changes were seen in other parameters such as lymphoblastogenesis and IL2 production. These results suggested that the effect on the immune system caused by the administration of rEPO was only transient and is likely to be non-specific. With respect to the effects of rEPO on immunological parameters, the responding area in the skin test with PPD was significantly increased after the administration of rEPO, suggesting improvement in cellular immune functions. Adverse reactions were observed in six cases and administration was discontinued in two cases.
