|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
TISSUE-SPECIFIC STEM CELLS |
aMolecular Medicine and Gene Therapy, Lund University, Lund, Sweden;
bDepartment of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan;
cClinic for Internal Medicine C, Department of Hematology and Oncology, Ernst-Moritz-Arndt University of Greifswald, Greifswald, Germany;
dDepartment of Safety Research on Blood and Biologics, National Institute of Infectious Diseases, Tokyo, Japan
Key Words. Anemia • Apoptosis • Erythropoiesis • Lentiviral vector
Correspondence: Correspondence: Stefan Karlsson, M.D., Ph.D., Molecular Medicine and Gene Therapy, Lund University, BMC A12, 221 84, Lund, Sweden. Telephone: 46-222-05-77; Fax: 46-222-05-78; e-mail: stefan.karlsson{at}med.lu.se
Received on July 18, 2007;
accepted for publication on October 22, 2007.
Disclosure of potential conflicts of interest is found at the end of this article.
First published online in STEM CELLS EXPRESS October 25, 2007.
Diamond-Blackfan anemia (DBA) is a congenital red-cell aplasia in which 25% of the patients have a mutation in the ribosomal protein (RP) S19 gene. It is not known how the RPS19 deficiency impairs erythropoiesis and proliferation of hematopoietic progenitors. To elucidate molecular mechanisms in RPS19-deficient DBA, we analyzed the effects of RPS19 deficiency on erythropoietin (EPO)-induced signal transduction, cell cycle, and apoptosis in RPS19-deficient TF-1 cells. We did not find any abnormality in EPO-induced signal transduction. However, RPS19-deficient TF-1 cells showed G0/G1 arrest (82% vs. 58%; p < .05) together with accumulation of p21 and p27. The fraction of apoptotic cells detected by Annexin V analysis also increased compared with control cells (13% vs. 3.1%; p < .05). Western blot analysis of apoptosis-related proteins showed that the level of bcl-2 and Bad was decreased and Bax was increased in RPS19-deficient TF-1 cells. Moreover, primary CD34-positive cells from DBA patients detected by Annexin V analysis also generated a higher number of apoptotic cells compared with normal CD34-positive cells during in vitro culture (38% vs. 8.9%; n = 5; p < .001). Finally, we show that although RPS19 silencing reduces EPO-induced development of erythroid progenitors expressing glycophorin A (GPA), RPS19 silencing in cells already expressing GPA does not affect GPA expression. These findings indicate that RPS19 deficiency causes apoptosis and accelerated loss of erythroid progenitors in RPS19-deficient DBA.
This article has been cited by other articles:
![]() |
T. Uechi, Y. Nakajima, A. Chakraborty, H. Torihara, S. Higa, and N. Kenmochi Deficiency of ribosomal protein S19 during early embryogenesis leads to reduction of erythrocytes in a zebrafish model of Diamond-Blackfan anemia Hum. Mol. Genet., October 15, 2008; 17(20): 3204 - 3211. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| STEM CELLS | THE ONCOLOGIST | CME | ALPHAMED PRESS JOURNALS |