Chimeric Ad5F35 adenoviral vector-mediated expression of mutant IκBα induces apoptosis of leukemia cells / 中国实验血液学杂志

Constitutive activation of nuclear transcription factor-κB (NF-κB) exists in a variety of leukemia, and induction of apoptosis through blocking NF-κB activation may be an alternative strategy for leukemia treatment. The aim of this study was to investigate the inducing effect of modified adenovirus 5-based adenovirus vector (i.e. chimeric Ad5F35 Vec)-mediated expression of mutant IκBα (IκBαDN) on apoptosis of HL-60 cells. The recombinant Ad5F35-IκBαDN Vec carrying IκBαDN cDNA which deleted the first 1-70 amino acids coding sequences at 5' terminal of human IκBα was transfected into HL-60 cells. The apoptosis, NF-κB DNA binding activity, the expressions of IκBα, cIAP-2 and xIAP in HL-60 cells were detected by DNA binding assay, flow cytometry, real-time quantitative polymerase chain reaction and Western blot respectively. The results showed that apoptosis rates were 22.53 ± 2.999%, 6.08 ± 2.464% and 4.86 ± 1.366% for Ad5F35-IκBαDN Vec-infected or blank vector of Ad5F35-EGFP Vec-transfected and untransfected HL-60 cells respectively, which showed a significant difference between Ad5F35-IκBαDN Vec-transfected and untransfected cells (p < 0.001) and between Ad5F35-IκBαDN Vec-transfected and Ad5F35-EGFP Vec-transfected cells (p < 0.001, p < 0.002), while NF-κB DNA binding activity was decreased, the truncated IκBα was expressed, and IκBα mRNA expression was up-regulated, but the expression of cIAP-2 and xIAP mRNA was down-regulated after transduction for 48 hours. It is concluded that the chimeric Ad5F35 Vec can effectively mediate the expression of IκBαDN cDNA in HL-60 cells, leading to the inhibition of NF-κB DNA binding activity and inducing apoptosis of HL-60 cells.

CD34(+)/CD123(+) cell sorting from the patients with leukemia by Midi MACS method / 中国实验血液学杂志

The aim of this study was to sort the CD34(+)/CD123(+) cells from the bone marrow cells of patients with acute myeloid leukemia (AML) by Midi MACS method. Firstly, the bone marrow mononuclear cells (BMMNC) were isolated from the patients with AML with Ficoll Paque, CD34(+) cells were then isolated by Midi MACS method followed by the isolation of CD34(+)/CD123(+) cells from the fraction of CD34(+) cells. The enrichment and recovery of CD34(+) and CD34(+)/CD123(+) cells were assayed by FACS technique. The results showed that the enrichment of CD34(+) cells was up to 98.73%, its average enrichment was 95.6%, and the recovery of CD34(+) was 84.6%, its average recovery was 51% after the first round sorting, by the second round sorting, the enrichment of CD34(+)/CD123(+) cells was up to 99.23%, its average enrichment was 83%. With regard to BMMNCs before sorting, the recovery of CD34(+)/CD123(+) was 34%. But, on the CD34(+) cells obtained by the first round sorting, its recovery was 56%. In conclusion, these results confirmed that the method of Midi MACS sorting can be applied to sort CD34(+)/CD123(+) cells from the bone marrow cells of AML patients, which give rise to the similar enrichment and recovery of the sorted cells with that of literature reported by the method of FACS.

Expression of coagulation factor IX in human CD34 + hematopoietic stem cells by adeno-associated virus 2 / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the expression of human coagulation factor IX (hFIX) gene in human umbilical cord blood (CB) CD34+ cells which was transfected with recombinant adeno-associated virus 2 (rAAV-2).</p><p><b>METHOD</b>The CD34+ cells were transfected with rAAV-2/hFIX and cultured for 21 days for inducing differentiation into myeloid, erythroid and megakaryocytes, respectively. The expression of hFIX was studied at mRNA, protein and biological activity levels. The cytotoxicity of rAAV-2 to CD34+ cells was evaluated by cell proliferation, cell vitality, CD antigen expressions and CFU yields.</p><p><b>RESULTS</b>The hFIX mRNA was expressed in the cultured cells which was verified by RT-PCR and DNA sequencing. An elevated level of hFIX expression and biological activities were detected with a maximum amount of 14.10 ng/10(6) cell x 24 h. During the period of 21 day culture, the cell vitality, cell proliferation, CD antigen expression and CFU yields between the transfected and un-transfected groups had no difference(P > 0.05).</p><p><b>CONCLUSION</b>The human CB CD34+ cells are able to produce functional hFIX after transduction by rAAV-2/hFIX. The cell proliferation and differentiation capacities of the host CD34+ cells were not affected by rAAV-2.</p>