Ex vivo expansion and clonal variation of CD34(+)CD59(+) cells from bone marrow in children with paroxysmal nocturnal hemoglobinuria / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the isolation, purification and ex vivo expansion of CD34(+)CD59(+) cells from the bone marrow of children with paroxysmal nocturnal hemoglobinuria (PNH), to evaluate the capability of long-term hematopoietic reconstruction of the expanded CD34(+)CD59(+) cells, and to provide a laboratory basis for novel treatment of PNH.</p><p><b>METHODS</b>CD34(+)CD59(+) cells were isolated from the bone marrow mononuclear cells of children with PNH using immunomagnetic beads and flow cytometer in sequence. The isolated cells were subjected to ex vivo expansion in the presence of different combinations of hematopoietic growth factors for two weeks. The colony-forming cells and long-term culture-initiating cells (LTC-ICs) were cultured and counted.</p><p><b>RESULTS</b>The optimal combination of hematopoietic growth factors for ex vivo expansion was stem cell factor+interleukin (IL)-3+IL-6+FLT3 ligand+thrombopoietin+ery-thropoietin, and maximum expansion (30.4 ± 6.7 folds) was seen on day 7 of days 4 to 14 of ex vivo expansion. After ex vivo expansion, CD34(+)CD59(+) cells remained CD59-positive, retained strong capability of forming colony-forming units, and could still form LTC-ICs. There was no significant difference in capability of forming LTC-ICs between CD34(+)CD59(+) cells before and after expansion. The expansion capability of CD34(+)CD59(+) cells from children with PNH was significantly lower than that of CD34(+) cells from normal controls (P<0.01).</p><p><b>CONCLUSIONS</b>The CD34(+)CD59(+) cells from children with PNH can be expanded in vitro. Post-expansion CD34(+)CD59(+) cells retain capability of long-term hematopoietic reconstruction. CD34(+)CD59(+) cells showed no trend towards PNH clone during culture. Ex vivo expansion of CD34(+)CD59(+) cells from children with PNH might be practical in performing autologous transplantation clinically for these children.</p>

Mobilization of bone marrow-derived Nkx2-5(+) cardiac progenitor cells under condition of acute myocardial ischemia / 生理学报

The present study aimed to observe the morphological distribution of bone marrow (BM)-derived Nkx2-5(+) cardiac progenitor cells (CPCs) in bone marrow niche and evaluate the effect of acute myocardial ischemia (AMI) on the mobilizion of BM-derived Nkx2-5(+) CPCs. Animal models of BALB/c mouse AMI, cerebral and hind-limb ischemia were established. Nanogold labeling method, immunofluorescence and Western blot were used to identify the distribution of BM-derived Nkx2-5(+) CPCs and the expressions of Nkx2-5 protein in peripheral blood and BM after AMI. Meanwhile, in different ischemia organ models and after AMD3100 (SDF-1/CXCR4 antagonist) pretreatment in AMI model, Nkx2-5 protein expressions in peripheral blood were also assayed. Nkx2-5(+) CPCs were found to locate in cavitas medullaris. The percentage of Nkx2-5(+) CPCs in blood increased immediately after AMI. Nkx2-5 protein expression in peripheral blood was also upregulated at the timepoint of 24 h post-AMI (P<0.01) and kept stable without further enhancement from day 1 to day 7 post-AMI. In BM, Nkx2-5 protein expression was upregulated immediately after AMI and downregulated afterwards (P<0.01). After AMD3100 pretreatment in AMI group, Nkx2-5 protein expression was significantly inhibited in peripheral blood (P<0.05). In cerebral and hind-limb ischemia models, Nkx2-5 protein expressions were significantly lower than that in AMI group (P<0.01), but with no significant difference to control group. These results suggest that Nkx2-5(+) CPCs are physiologically resident in BM and AMI initiates mobilization of BM-derived Nkx2-5(+) CPCs in a predominant organ-specific manner. In the procedure of mobilization, SDF-1 may play a critical role in a chemoattracted manner.

High power microwave radiation damages blood-testis barrier in rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To determine the effect of high power microwave (HPM) radiation on the structure and function of blood-testis barrier (BTB) in rats.</p><p><b>METHODS</b>One hundred and sixty-six male Wistar rats were treated by heart perfusion of lanthanum-glutaraldehyde solution and tail vein injection of evans blue (EB) at 6 h, 1, 3, 7 and 14 d after exposed to 0, 10, 30 and 100 mW/cm2 HPM radiation for 5 minutes, the structural change of BTB and distribution of lanthanum or EB observed through the light microscope, electron microscope and laser scanning confocal microscopy (LSCM).</p><p><b>RESULTS</b>Testicular interstitial edema, vascular congestion or hyperemia with accumulation of plasma proteins and red blood cells in the inner compartment of seminiferous tubules were observed after exposure to HPM. The above-mentioned pathological changes were aggravated at 1-7 d and relieved at 14 d after radiation, obviously more severe in the 30 and 100 mW/cm2 exposure groups than in the 10 mW/cm2. Both lanthanum precipitation and EB were deposited in the inner compartment.</p><p><b>CONCLUSION</b>HPM radiation may damage the structure and increase the permeability of BTB.</p>

Delayed disappearance of h-VEGF₁₆₅ mRNA and protein under regulation of hypoxic response element / 生理学报

Transfer of vascular endothelial growth factor (VEGF) gene to ischemic myocardium may provide a useful approach for angiogenesis and improve cardiac performance. However, uncontrolled expression of VEGF in vivo may result in certain side effects, such as hemangioma formation, retinopathy, and tumor development. We investigated the feasibility of using the nine copies of hypoxic response element (HRE) to control the expression of human VEGF(165) (h-VEGF(165)) under anoxic condition at cell level and also observed the synchron of h-VEGF(165) mRNA and protein expressions. Recombinant adeno-associated viral (rAAV) vector was prepared by using the three-plasmid system and cotransfected to human embryo kidney 293T cells by the calcium phosphate precipitates method. The rAAV vector was purified by chloroform-PEG8000/NaCl-chloroform and added to cultured myocardiocytes. Myocardiocytes of Sprague-Dawley rat were cultured in serum-free medium and then randomly divided into eight groups. Group I: cultured under normoxic conditions (21% O2) for 8 h as control; Group II: cultured under anoxic conditions (1% O2) for 8 h; Group III: cultured under normoxic conditions (21% O2) for 8 h with gene transfer; Group IV: cultured under anoxic conditions (1% O2) for 8 h with gene transfer; Group V, VI, VII: cultured under anoxic conditions (1% O2) for 8 h with gene transfer and then tured to normoxic conditions (21% O2) for 4, 8 or 12 h, respectively; Group VIII: cultured under anoxic conditions (1% O2) for 20 h with gene transfer. After completion of cell culture, the amount of h-VEGF(165) protein in culture supernatant was quantified by using enzyme linked immunosorbent assay (ELISA). Expression of h-VEGF(165) protein in cultured cardiacmyocytes was also evaluated by immunofluorescence. RT-PCR was employed to detect the expression of h-VEGF(165) mRNA. The results revealed that there were no expressions of h-VEGF(165) mRNA and protein in groups I, II, III, VI and VII. After gene transfer, the expressions of h-VEGF(165) protein and mRNA were significantly higher in groups IV and VIII than those in other groups (P<0.01); Immunofluorescence positive cells were observed in groups IV, V and VIII. RT-PCR revealed that a 484-bp strip can be found in groups IV and VIII, but unavailable in other groups. We conclude that HRE is a promising regulator for h-VEGF(165) gene expression following the changes of oxygen environment. HRE can induce the expression of h-VEGF(165) gene after hypoxia, but in normal oxygen condition, the expression of h-VEGF(165) was inhibited. Although expression of h-VEGF(165) mRNA ceased in normal oxygen condition under the control of HRE, expression of h-VEGF(165) protein was hysteretic to h-VEGF(165) mRNA expression.

Effects of endothelin-1 on differentiation of cardiac myocyte induced from rabbit bone marrow stromal cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cardiomyocyte transplantation for the therapy of myocardial ischaemia is being paid close attention. However, how the microenvironment controls the differentiation of transplanted bone marrow stromal cells (BMSCs) is unknown. Endothelin-1 (ET-1), a cytokine, increases during myocardial infarction, but it is not known whether ET-1 is responsible for the fate of transplanted BMSCs. In the present study, we investigated the effects of ET-1 on differentiation and maturation of induced rabbit BMSCs, in vitro, to elucidate the cellular biological mechanisms.</p><p><b>METHODS</b>The proliferation of BMSCs isolated from femur of rabbits was induced by ET-1 only, by 5-azacytidine (5-aza) or ET-1 combined with 5-aza. After 4 weeks of induced culturing, the differentiation rate and the diameter of induced myocyte like cells were estimated and the expressions of GATA-4 protein and phosphorylation level were assayed by Western-blot, RT-PCR analysis of beta-myosin heavy chain (MHC). mRNA expression, levels of troponin-I by immunohistochemical staining and ultrastructure of induce-cultured BMSCs were also determined.</p><p><b>RESULTS</b>By induction with ET-1 and 5-aza, mean cell diameter of induced BMSCs was larger than induced with 5-aza [(6.26 +/- 0.22) microm cf (5.29 +/- 0.19) microm] (P < 0.001). There was no difference in rate of differentiation of myocyte like cells between the groups induced with 5-aza and ET-1 combined with 5-aza [(29.82 +/- 0.23)% cf (29.94 +/- 0.18)%] (P > 0.05). The expressions of GATA-4 protein and phosphorylation were enhanced significantly in groups induced with ET-1 combined with 5-aza (P < 0.05). In the group induced with ET-1 combined with 5-aza, expression of beta-MHC mRNA was higher than control [(0.122 +/- 0.008) cf (0.022 +/- 0.003)] (P < 0.01), and more troponin-I positive cells were also detected in this group. Differentiated BMSCs showed formations of myofilaments and primitive sarcomere, i.e., morphological characteristics of myocyte like cells.</p><p><b>CONCLUSIONS</b>This study suggests that induced culturing of BMSCs by ET-1 combined with 5-aza can express cardiomyocytic characteristics whereas ET-1 alone could not induce BMSCs to differentiate to myocyte like cells. ET-1 upregulates the expression of GATA-4 protein and phosphorylation level of induced BMSCs, and rapidly promotes the differentiation and maturation of myocyte like cells from BMSCs.</p>

Myocardioprotective effects of the combination of ischemic preconditioning with hypothermia and crystalloid cardioplegia in immature rabbits / 生理学报

This study was undertaken to explore the myocardioprotective effects of the combination of ischemic preconditioning (IP) with hypothermia and St.II Thomas crystalloid cardioplegic solution (CCS) on immature hearts in the rabbit. Isolated immature rabbit hearts were perfused with Krebs-Henseleit bicarbonate buffer on Langendorff apparatus. In experiment 1, 24 hearts were divided into 4 groups (n=6 in each group): Con, IP1, IP2 and IP3 group. Hearts of the four groups underwent 0, 1, 2 or 3 cycles of IP respectively. Then all the hearts were subjected to a sustained ischemia period of 2 h at 20 degrees C and a postischemic reperfusion period of 30 min at 37 degrees C. In experiment 2, 48 hearts were divided into 6 groups (n=8 in each group): SCon1, SIP1, SCon2, SIP2, SCon3 and SIP3 group, according to hypothermia and the duration of sustained ischemia (30 min at 32 degrees C; 90 min at 25 degrees C, 2 h at 20 degrees C). The SIP1, SIP2 and SIP3 groups were preconditioned twice before the sustained hypothermic ischemia, while the SCon1, SCon2 and SCon3 groups were not preconditioned. CCS was applied during sustained ischemia, all the hearts were reperfused for 30 min at 37 degrees C. Heart rate (HR), left ventricular developed pressure (LVDP) and peak rate of increase or decrease of left ventricular pressure (+/-dp/dt(max)) were recorded. Tissue concentration of adenosine triphosphate (ATP), malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were measured. At the end of reperfusion, values of product of LVDP and HR, +/-dp/dt(max) in IP2 group were 96%+/-21%, 101%+/-19% and 84% +/-15% of the baseline values respectively, which were significantly higher than those of Con group and IP3 group (P<0.01, P<0.05); also, the ATP content of IP2 group was higher than that of the Con group (P<0.01). When CCS was applied during sustained period of hypothermic ischemia at 32 degrees C or 25 degrees C, recovery rates of RPP (rate product, =LVDPxHR) and +dp/dt(max) in SIP1 group were 87% +/-14% or 99% +/-26% of the baseline values respectively (P<0.05, vs SCon1 group), the values in SIP2 group changed to 87% +/-16% or 102% +/-20% respectively (P<0.05, vs SCon2 group). Contents of ATP in SIP1 and SIP2 groups were significantly higher than those of SCon1 or SCon2 groups respectively (P<0.05), but MDA content of the two groups were significantly lower than those of SCon1 or SCon2 groups (P<0.05) respectively. The study indicates that IP attenuates hypothermic ischemia/reperfusion injury to immature rabbit hearts under 20 degrees C ischemia, two cycles of IP showing better myocardioprotective effects than 1 or 3 cycles of IP. When IP was combined with CCS which were applied during hypothermic ischemia period, the beneficial effects of IP were weakened as the temperature during the hypothermic period was elevated.

Application of double immunomagnetic positive sorting to ex vivo expansion of marrow CD34(+)CD59(+) cells from patients with paroxysmal nocturnal hemoglobinuria / 中国实验血液学杂志

Since flow cytometry was not feasible for sorting a huge amount of cells for clinical use, the method of double immunomagnetic positive sorting was used for selection of CD34(+)CD59(+) cells from bone marrow mononuclear cells in patients with paroxysmal nocturnal hemoglobinuria (PNH), which laid the groundwork for clinical ABMT/APBSCT of patients with PNH. Immunomagnetic positive selection was used for two times, the microbeads were removed from the CD34(+) cells selected firstly by means of overnight culture, then the sufficient CD34(+)CD59(+) cells were used for ex vivo expansion. The results showed that the survival, proliferation and colony-forming units of the selected CD34(+)CD59(+) cells by double immunomagnetic positive sorting had no significant difference as compared with that of CD34(+)CD59(+) cells selected by flow cytometry technique. It is suggested that the double immunomagnetic positive sorting promotes the use for separation and purification hematopoietic stem/progenitor cells and other cells with double or multiple markers cells for autologous hematopoietic stem cell transplantation in PNH patients.

Study of biological characteristics of the CD(34)(+) CD(59)(+) and CD(34)(+) CD(59)(-) cells from PNH patients' bone marrow / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the characteristics of CD(34)(+) CD(59)(+) cells from paroxysmal nocturnal hemoglobinuria(PNH) patients' bone marrow and the possible reasons of hematopoietic clonal dominance of PNH clones.</p><p><b>METHODS</b>CD(34)(+) CD(59)(+) and CD(34)(+) CD(59)(-) cells from PNH patients and CD(34)(+) cells from normal control were selected from the bone marrow mononuclear cells by means of immunomagnetic microbead-flow cytometry two step sorting method undergone ex vivo expansion in liquid culture for two weeks and performed semisolid cultures before and after expansion.</p><p><b>RESULTS</b>(1) Cultivation for seven days was the optimum for ex vivo expansion of PNH CD(34)(+) CD(59)(+) cells and normal CD(34)(+) cells, both cell populations remained CD(59) positive after expansion. (2) Normal CD(34)(+) cells had higher capacities of proliferation and expansion, and stronger potential to survival than that of both PNH CD(34)(+) CD(59)(+) and PHN CD(34)(+) CD(59)(-) cells. (3) In terms of semisolid culture, there was no significant difference in the yields of CFU formation between CD(34)(+) CD(59)(+) and CD(34)(+) CD(59)(-) cells. (4) In liquid culture with combinations of hematopoietic factors SCF + IL-3 + IL-6 + FL + Tpo or SCF + IL-3 + IL-6 + FL + Tpo + Epo, there was no significant difference in the capabilities of survival, proliferation and expansion between CD(34)(+) CD(59)(+) and CD(34)(+) CD(59)(-) cells; but with combination of SCF + IL-3 + IL-6 + FL + Tpo + Epo + GM-CSF, CD(34)(+) CD(59)(-) cells had better proliferation and expansion capacities and stronger potential to survival than that of CD(34)(+) CD(59)(+) cells.</p><p><b>CONCLUSIONS</b>(1) Normal CD(34)(+) cells had better proliferation, expansion capacities and stronger potential to survival than that of PNH CD(34)(+) CD(59)(+)cells. (2) In semisolid and liquid culture with hematopoietic factor combinations, there was no significant difference in the capabilities of survival, proliferation and expansion between CD(34)(+) CD(59)(+) and CD(34)(+) CD(59)(-) cells. It was suggested that CD(34)(+) CD(59)(-) cells had no clonal hemotopoiesis dominance. GM-CSF might be one of the reasons for PHN clones to possess clonal hematopoiesis dominance.</p>

Comparison of capabilities of survival, proliferation and expansion between CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore in vitro expansion of CD34+CD59+ cells from patients with PNH, and compare the capabilities of survival, proliferation and expansion between CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control.</p><p><b>METHODS</b>CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control were selected from the bone marrow mononuclear cells by means of two-step sorting method with immunomagnetic microbead-flow cytometry, then underwent in vitro expansion for two weeks and semi-solid culture in vitro before and after expansion.</p><p><b>RESULTS</b>(1) CD34+CD59+ cells from patients with PNH can be expanded effectively in vitro, and the biggest expansion of CD34+CD59+ cells was about 23.49 fold on the 7th day. (2) There were some similar characteristics between CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control, such as: the best combination of hematopoietic factors for in vitro expansion was SCF+ IL-3 + IL-6 + FL + Tpo + Epo, and the seventh day was the most suitable in course of 4-14 days for in vitro expansion, and after in vitro expansion, the cells remained CD59 positive and strong capability of performing colony-forming. (3) CD34+ cells from normal control had better proliferation, expansion and stronger potential to survive than CD34+CD59+ cells from patients with PNH.</p><p><b>CONCLUSIONS</b>(1) In vitro expansion of CD34+CD59+ cells from patients with PNH can be performed. The present study showed the possibility of performing ABMT or APBSCT clinically for patients with PNH. (2) There were some similar characteristics between CD34+CD59+ cells from patients with PNH and CD34+ cells from normal control, but the latter had better proliferation, expansion and stronger potential to survive than the former. CD34+CD59+ cells from patients with PNH were not completely normal cells.</p>