Organic osmolyte channels in malaria-infected erythrocytes.

摘要

Infection of human erythrocytes with the malaria parasite Plasmodium falciparum induces activation of organic osmolyte and anion channels in the host cell membrane. These channels supply the intraerythrocytic parasite with nutrients, dispose of metabolic waste products, adjust the host electrolyte concentrations to the parasite's needs, and lower the colloid osmotic pressure, thus preventing premature hemolysis of the osmotically challenged host cell. Four different types of anion channels (CFTR, ClC-2 or PSAC, an 18pS inward rectifier, and an 80pS outward rectifier) have been identified in human erythrocytes. Here, we show that the 80pS channels underlie a serum albumin-dependent anion current. Both, the parasite in vitro development and the organic osmolyte permeability of the parasitized erythrocyte, reportedly depend on serum albumin, highlighting the pivotal functional significance of the 80pS channel for the intraerythrocytic parasite development.