• Molecules and Cells
• /
• v.25 no.4
• /
• pp.487-493
• /
• 2008

HoxB4 has been shown to enhance hematopoietic engraftment by hematopoietic stem cells (HSC) from differentiating mouse embryonic stem cell (mESC) cultures. Here we examined the effect of ectopic expression of HoxB4 in differentiated human embryonic stem cells (hESCs). Stable HoxB4-expressing hESCs were established by lentiviral transduction, and the forced expression of HoxB4 did not affect stem cell features. HoxB4-expressing hESC-derived CD34+ cells generated higher numbers of erythroid and blast-like colonies than controls. The number of CD34+ cells increased but CD45+ and KDR+ cell numbers were not significantly affected. When the hESC derived CD34+ cells were transplanted into $NOD/SCID{\beta}2m-/-$ mice, the ectopic expression of HoxB4 did not alter their repopulating capacity. Our findings show that overexpression of HoxB4 in differentiating hESCs increases hematopoietic colony formation and hematopoietic cell formation in vitro, but does not affect in vivo repopulation in adult mice hosts.

• The Korean Journal of Physiology and Pharmacology
• /
• v.16 no.4
• /
• pp.265-271
• /
• 2012

HoxB4, a homeodomain-containing transcription factor, is involved in the expansion of hematopoietic stem cells and progenitor cells in vivo and in vitro, and plays a key role in regulating the balance between hematopoietic stem cell renewal and cell differentiation. However, the biological activity of HoxB4 in other cells has not been reported. In this study, we investigated the effect of overexpressed HoxB4 on cell survival under various conditions that induce death, using the Ba/F3 cell line. Analysis of phenotypical characteristics showed that HoxB4 overexpression in Ba/F3 cells reduced cell size, death, and proliferation rate. Moreover, the progression from early to late apoptotic stages was inhibited in Ba/F3 cells subjected to HoxB4 overexpression under removal of interleukin-3-mediated signal, leading to the induction of cell cycle arrest at the G2/M phase and attenuated cell death by Fas protein stimulation in vitro. Furthermore, apoptotic cell death induced by doxorubicin-treated G2/M phase cell-cycle arrest also decreased with HoxB4 overexpression in Ba/F3 cells. From these data, we suggest that HoxB4 may play an important role in the regulation of pro-B cell survival under various apoptotic death environments.

• Biomedical Science Letters
• /
• v.9 no.1
• /
• pp.1-8
• /
• 2003

Liver is an organ having an ability to regenerate by itself when it is damaged or removed. Since the research on the liver regeneration so far was regarding on the cellular multiplications not the formation of the shape, we intended to analyze the expression pattern of Hox genes during liver regeneration. RNA samples isolated from liver at the time of partial hepatectomy, 4 hours as well as 3 days later following regeneration were used to perform RT-PCR with Hox-specific degenerate primers. The PCR products were cloned, sequenced and analyzed through BLAST program. Genes belonging to the AbdB type Hox genes (paralogous groups IX-XIII) expressed predominantly during regeneration, while the other group (I-VII), especially Hoxal and bl seemed to be expressed continuously before and after regeneration. These data altogether imply that paralogous group IX and X genes including Hoxa10 and d10 seemed to be regeneration specific genes of liver.