TY - JOUR
T1 - The Rh complex exports ammonium from human red blood cells
AU - Hemker, Mirte B.
AU - Cheroutre, Goedele
AU - van Zwieten, Rob
AU - Maaskant-van Wijk, Petra A.
AU - Roos, Dirk
AU - Loos, Johannes A.
AU - van der Schoot, C. Ellen
AU - von dem Borne, Albert E. G. Kr
PY - 2003
Y1 - 2003
N2 - The Rh blood group system represents a major immunodominant protein complex on red blood cells (RBC). Recently, the Rh homologues RhAG and RhCG were shown to promote ammonium ion transport in yeast. In this study, we showed that also in RBC the human Rh complex functions as an exporter of ammonium ions. We measured ammonium import during the incubation of RBC in a solution containing a radiolabelled analogue of NH4Cl (C-14-methyl-NH3Cl). Rh-null cells of the regulator type (expressing no Rh complex proteins) accumulated significantly higher levels (P = 0.05) of radiolabelled methyl-ammonium ions than normal RBC, at room temperature. Rh-null cells of the amorph type (expressing limited amounts of Rh complex proteins) accumulated an intermediate amount of methyl-ammonium ions. To show that decreased ammonium export contributes to its accumulation, the release of intracellular methyl-ammonium from the cells was measured over time. In 30 s, normal RBC released 87% of the intracellular methyl-ammonium ions, whereas Rh-null cells of the regulator type released only 46%. We conclude that the Rh complex is involved in the export of ammonium from RBC
AB - The Rh blood group system represents a major immunodominant protein complex on red blood cells (RBC). Recently, the Rh homologues RhAG and RhCG were shown to promote ammonium ion transport in yeast. In this study, we showed that also in RBC the human Rh complex functions as an exporter of ammonium ions. We measured ammonium import during the incubation of RBC in a solution containing a radiolabelled analogue of NH4Cl (C-14-methyl-NH3Cl). Rh-null cells of the regulator type (expressing no Rh complex proteins) accumulated significantly higher levels (P = 0.05) of radiolabelled methyl-ammonium ions than normal RBC, at room temperature. Rh-null cells of the amorph type (expressing limited amounts of Rh complex proteins) accumulated an intermediate amount of methyl-ammonium ions. To show that decreased ammonium export contributes to its accumulation, the release of intracellular methyl-ammonium from the cells was measured over time. In 30 s, normal RBC released 87% of the intracellular methyl-ammonium ions, whereas Rh-null cells of the regulator type released only 46%. We conclude that the Rh complex is involved in the export of ammonium from RBC
U2 - https://doi.org/10.1046/j.1365-2141.2003.04425.x
DO - https://doi.org/10.1046/j.1365-2141.2003.04425.x
M3 - Article
C2 - 12846905
SN - 0007-1048
VL - 122
SP - 333
EP - 340
JO - British journal of haematology
JF - British journal of haematology
IS - 2
ER -