Characteristic and prognostic significance of leukemia stem cells associated antigens expressions in t (8;21) acute myeloid leukemia / 中华血液学杂志

Objective@#To investigate the characteristic and prognostic significance of leukemia stem cells associated antigens expressions including CD34, CD38, CD123, CD96 and TIM-3 in t (8;21) AML.@*Methods@#Bone marrow samples of 47 t (8;21) AML patients were collected at diagnosis from October 2015 to April 2018 in Peking University Peoples’ Hospital, then flow cytometry method was performed to detect the expression frequencies of CD34, CD38, CD123, CD96 and TIM-3 to analyze the relationship between leukemia stem cells associated antigens expressions and relapse.@*Results@#Of 47 t (8;21) AML patients tested, the median percentages of CD34+CD38-, CD34+ CD38-CD123+, CD34+CD38- CD96+ and CD34+ CD38- TIM-3+ cells among nucleated cells were 2.37%, 0.24%, 0.27% and 0.06%, respectively. All the frequencies of CD34+CD38-, CD34+CD38-CD123+, CD34+CD38-CD96+ and CD34+ CD38-TIM-3+ cells had no impact on the achievement of CR after the first course of induction. All higher frequencies of CD34+CD38-, CD34+CD38-CD123+, CD34+CD38-CD96+ cells were related to higher 2-year CIR rate. Whereas, the frequency of CD34+ CD38- TIM-3+ cells had no impact on CIR rate. Both high frequency of CD34+ CD38- cells and the high level of minimal residual diseases (patients with <3-log reduction in the RUNX1-RUNX1T1 transcript level after the second consolidation therapy) were independent poor prognostic factors of CIR[P=0.025, HR=6.9 (95%CI 1.3-37.4) ; P=0.031, HR=11.1 (95%CI 1.2-99.2) ].@*Conclusion@#Different leukemia stem cells associated antigens had distinct prognostic significance in t (8;21) AML. High frequencies of CD34+ CD38-, CD34+ CD38- CD123+ and CD34+CD38-CD96+ cells at diagnosis predicted relapse in patients with t (8;21) AML.

Stem Cells Expressing Homing Receptors Could be Expanded From Cryopreserved and Unselected Cord Blood

We assessed the cytokine combinations that are best for ex vivo expansion of cord blood (CB) and the increment for cell numbers of nucleated cells, as well as stem cells expressing homing receptors, by an ex vivo expansion of cryopreserved and unselected CB. Frozen leukocyte concentrates (LC) from CB were thawed and cultured at a concentration of 1x10(5)/mL in media supplemented with a combination of SCF (20 ng/mL)+TPO (50 ng/mL)+FL (50 ng/mL)+/-IL-6 (20 ng/mL)+/-G-CSF (20 ng/mL). After culturing for 14 days, the expansion folds of cell numbers were as follows: TNC 22.3+/-7.8~26.3+/-4.9, CFU-GM 4.7+/-5.1~11.7+/-2.6, CD34+CD38- cell 214.0+/-251.9~464.1+/-566.1, CD34+CXCR4+ cell 4384.5+/-1664.7~7087.2+/-4669.3, CD34+VLA4+ cell 1444.3+/-1264.0~2074.9+/-1537.0, CD34+VLA5+ cell 86.2+/-50.9~ 113.2+/-57.1. These results revealed that the number of stem cells expressing homing receptors could be increased by an ex vivo expansion of cryopreserved and unselected CB using 3 cytokines (SCF, TPO, FL) only. Further in vivo studies regarding the engraftment after expansion of the nucleated cells, as well as the stem cells expressing homing receptors will be required.

In vivo transfer of human chemokine-like factor 1 gene increases peripheral blood CD34~+ stem cells after myocardial infarction in rats / 北京大学学报(医学版)

Objective: To assess the influence of different doses of CKLF1 plasmid on the dynamics and magnitude of the mobilization of the mobilization bone of marrow stem cells in a rat AMI model.Methods: Different doses of plasmid DNA encoding CKLF1 gene,empty plasmid or saline were injected into male SD rats intramuscularly with in vivo electroporation.Rats were subjected to left coronary artery ligation 6 days after gene transfer.Peripheral blood samples were drawn and CD34~+ cells were assayed by FACS calibur flow-cytometer.The changes in absolute number of CD34~+ cells were evaluated.Results: Expressions of CKLF1 mRNA and protein were detected in the injection site 7 days after gene transfer.Five days after gene transfer,the CD34~+ cells numbers in CKLF1 groups were significantly higher than those in empty plasmid group,especially in CKLF1 100?g group(16.63?10~6/L vs 4.98?10~6/L,P

Expression of Cyclooxygenase-2 and Its Correlation with Clinicopathologic Factors of Ampulla of Vater Cancer

There has been no report for the expression of cyclooxygenase-2 (COX-2) and its clinicopathologic and biologic significance in ampulla of Vater cancer. This study was aimed for the clarification of COX-2 expression and its biologic roles in ampulla of Vater cancer. Fourty-six patients with ampulla of Vater cancer were enrolled and their COX-2 expression and clinicopathologic features were analyzed. The median age of patients was 60 yr and the mean duration of follow-up was 35 months (range: 14-82 months). Immunohistochemical stainings for COX-2, Ki-67, CD34 and TUNEL staining were performed. The immunoreactive COX-2 expression was present in 24 (52.2%) patients of ampulla of Vater cancer and mainly localized in cytosolic and perinuclear region. There was no significant difference in the length of survival between COX-2 postive and negative group (p=0.9420 by Log Rank test). Also, there were no significant differences of proliferation index (p=0.326), apoptotic index (p=0.764) and microvessel density (p=0.135) between COX-2 positive and negative group. Initial pTNM stage (p=0.0028 by Log Rank test) and blood transfusion over 4 pints during operation (p=0.0254 by Log Rank test) were independent prognostic factor in patients with ampulla of Vater cancer. It is suggested that immunoreactivity of COX-2 is not correlated with clinicopathologic and biologic features of ampulla of Vater cancer.

CONSTRUCTION OF CD34 EXTRACELLULAR REGION ENCODING cDNA CLONE, AND EUKARYON EXPRESSION VECTOR AND ITS PRELIMINARY APPLICATION IN MONOCLONAL ANTIBODY PREPARATION BY GENE IMMUNIZATION / 解放军医学杂志

Objective To clone CD34 extracellular region encoding cDNA and to construct its eukaryon expression vector to explore the feasibility of its monoclonal antibody preparation by gene immunization. Methods Total RNA was extracted from KG-1a cell lines. CD34 extracellular region encoding genes were amplified by RT-PCR method and then confirmed by enzymatic lysis and DNA sequencing, and its eukaryon expression vector was constructed as pcDNA3.1-CD34. Twelve BABL/c mice aged 4-6 weeks were selected and randomly divided into 3 groups. Before immunization, 50?l 25% saccharin solution was injected into mouse musculus quadriceps femoris. Fifteen minutes later, blank control PBS, PBS diluted empty vector pcDNA3.1(50?g), or PBS diluted pcDNA3.1-CD34 was injected into the same site of the above three groups, respectively. Immunization was taken every two weeks for a total of three times. The antibody was detected regularly by FACS using tail blood from immunized mice. Results The results demonstrated that the length of CD34 cDNA was 886bp which was identical to the theoretical value and its sequence was confirmed by DNA sequencing which was identical to the registered sequence. The accuracy of CD34 expression vector recombination was confirmed by restriction enzymatic lysis. Hind III and EcoRI restriction enzymatic lysis sites were introduced into 5 and 3 terminals of amplified cDNA sequence, respectively. Terminate code TGA was also introduced into CD34 extracellular encoding cDNA. The expression vector possessing target genes was named as pcDNA3.1-CD34. FACS detection indicated that only 1/4(25%) immunized mice had a lower titer CD34 antibody in their tail vein serum 2-6 weeks after immunization, and the others did not show no antibody production. Conclusion The eukaryon expression vector pcDNA3.1-CD34, which express CD34 extracellular region, has been constructed. The feasibility of CD34 McAb preparation can primarily be confirmed by gene immunization.

Human bone marrow stromal cells in combination with exogenous cytokines to support in vitro expansion of cord blood CD_(34)~+ cells / 中国输血杂志

Objective To elucidate the role of human bone marrow stromal cells (hBMSC) in combination with exogenous cytokines such as stem cell factor(SCF) and FLT 3 ligand (FL) in supporting the in vitro expansion of CD 34 + cells purified from cord blood.Methods CD 34 + cells were isolated from umbilical cord blood by using a high gradient magnetic cell sorting system(MACS),expanded in combination with SCF,IL3 (interleukin 3),IL 6 (interleukin 6),FL,EPO (erythropoietin),and were planted onto the pre established irradiated (20Gy) stroma layer(hBMSC plus combinations of cytokines) respectively.On day 10,total cells were counted, and hematopoietic progenitor cells were assessed by semisolid culture assay,CD 34 + cells were quantitated by FACS.Results After separation by MACS,the frequency of CD 34 + cells was 92%?0.04%.On day 2,almost all the inoculated cells adhered to the stroma layer,with only a small number in the supernatant.Then,cells in the supernatant increased gradually, but the percentage of CD 34 + cells decreased.Compared with control, expansion fold of CD 34 + cells, CFU GM, BFU E were significantly higher in hBMSC group (P 0.5).Conclusion ① CD 34 + cells from cord blood formed foci adherent to the monolayer and colony forming cells remained in the culture of 10days,indicating that hBMSC can support hematopoiesis in vitro;②using human bone marrow stromal cells in cooperation with exogenous cytokines may be a feasible way to expand hematopoietic stem/progenitor cells.

The Effect of Basic Fibroblast Growth Factor (bFGF) on the Grafting Ability of CD34~+Cord Blood Cells / 中国输血杂志

Objective To investigate the effect of bFGF on the grafting ability (grafing efficiency)of CD34 + cord blood cells seeded in 5 FU injured human bone marrow stromal cells.Methods Using combined methods of bone marrow stromal cell culture system,light microscopy and electron microscopy,flow cytometry,we investigated the toxic effects of 5 FU on human bone marrow stromal cells (hBMSC) and the benefit of bFGF on dynamics of hBMSC as well as the ability of the cord blood stem cell to bind hBMSC.Results After 3 hours incubation with 5 FU,significant changes in hBMSC cytosolic and nuclear morphology were observed.Nuclear splitting and abnormal shapes of the pseudopodia were found under the electron microscope.Flow cytometry revealed that apoptosis appeared before G 0/G 1,and that cells in G 0/G 1and G 2/M phases were remarkably lower,while the cells in S phase were remarkably higher than the controls.Two hours after adding the cord blood hematopoietic progenitor cells,the group treated with bFGF(injury with intervention of bFGF group,IBG)showed higher proprtion of the adherence layer compared to the group without adding bFGF(injury group,IG)(29% versus 12%) Conclusion 5 FU causes DNA damage in hBMSC.It also impairs the binding ability of cord blood stem cell to hBMSC.bFGF is able to repair hBMSC damage and improve the binding of CD34 + cord blood hematopoietic progenitor cells onto hBMSC.