Removal of Urea in Uremia and Ammonia in Liver Failure with Emphasis on the Use of Artificial Cells for Encapsulation of Genetically Engineered Cells

Abstract

Dialysis is an effective treatment for chronic renal failure or uremia. Unfortunately, 85% of the world’s uremic patients die because their countries cannot afford dialysis therapy. Even in those countries that are treating the other 15% of the uremic patients, the total healthcare cost for this has been escalating to high levels. This is partly because success in the expensive dialysis treatment can now maintain uremic patients alive. This results in continuing increases in the number of dialysis patients. In any case, most patients would prefer an oral form of therapy rather than being attached to dialysis machines or receiving peritoneal dialysis. Many groups have studied a more affordable form of oral therapy for many years. A combination of adsorbents, osmotic agents, and other oral agents can control most of the problems related to accumulation of waste metabolites and water and electrolyte imbalances. Unfortunately, these groups ended their attempts at this many years ago because of the unavailability of an effective urea removal system. The hypothesis that high levels of ammonia can lead to hepatic comas in liver failure i receiving increasing support. An effective and fast ammonia removal system would therefore be useful here also. This chapter discusses the use of artificial cells for urea and ammonia removal, with emphasis on the use of encapsulated E. coli DH5 cells.