Therapeutic efficacy evaluation of rabbit anti-thymocyte globulin combined with cyclosporine A in children with aplastic anemia / 中国实验血液学杂志

This study was aimed to investigate the therapeutic efficacy of rabbit anti-thymocyte globulin (r-ATG) combined with cyclosporine A (CsA) and to analyse the efficacy-related factors in children with aplastic anemia (AA). Twenty five AA children treated with r-ATG [3.5 mg/(kg·d)×5 days] combined with CsA were analyzed retrospectively. The lymphocyte subgroups, CD4(+)/CD8 ratio and expression of CD55, CD59 on surface of neutrophils and erythrocytes in peripheral blood were detected by direct immunofluorescence method and flow cytometry; the responsive time, effective rate, adverse effects and infections after immunosuppressive therapy (IST) were analyzed; the distribution of T-lymphocyte subgroups in IST-effective and IST-uneffective groups was compared, and therapeutic efficacy-related factors were evaluated. The results showed that the response to treatments was found in 21 out of 25 cases, the total responsive rate was 84.0%; the response time was 3 - 6 months, average of 4 months; the effective rates in month 3, 6, 9, 12 after treatment were 56.0%, 72.0%, 80.0% and 84.0% respectively. The AA children with age ≥ 5 years old, course of disease < 6 months and absolute neutrophil value ≥ 1.5 ×10(9)/L on 30 days after IST had good curative effect; the effective rate in AA children with age ≥ 5 years old, course of disease < 6 months, high or reverse ratio of CD4(+)/CD8(+) and absolute neutrophil value ≥ 1.5×10(9)/L after IST was higher than that in AA children with age < 5 years old, course of disease ≥ 6 months, normal ratio of CD4(+)/CD8(+) and absolute neutrophil value after IST < 1.5×10(9)/L (94.4% vs 57.1%, 90.4% vs 50.0%, 94.1% vs 62.5%, 94.1% vs 62.5%) (P < 0.05). The high effective rate was observed in AA children with decrease of CD55 and CD59 expression, but there was no significant difference (P > 0.05) as compared with normal expression of CD55, CD59. It is concluded that the treatment using r-ATG (3.5 mg/kg·d × 5 d) combined with CsA is a safe and effective for children with AA. Age, course of disease and absolute neutrophil value on 30 days after IST are the main factors affecting curative affect.

Analysis of one case of adolescent blastic plasmacytoid dendritic cell neoplasm / 中国实验血液学杂志

This study was purposed to summarize the clinical characteristics and laboratorial data of blastic plasmacytoid dendritic cell neoplasm (BPDCN) in pediatric patients in order to enhance understanding this disease in diagnosis and therapy. A rare case of BPDCN in children was enrolled in this study. The blood routine test, examination of bone marrow cell morphology, histopathology and immunophenotype of the skin lesions were performed and analysed, the single cell suspensions of the biopsied skin mass were detected by flow cytometry. The results showed that tumor cells expressed CD4, CD56, CD43 and CD123, while not expressed CD19, CD20, CD3, CD8, CD13, CD11b and myeloperoxidase (MPO). According to the clinical and laboratorial features and the results from histopathological and immunophenotype examinations, BPDCN was confirmed. It is concluded that BPDCN in children is an extremely rare hematopoietic malignancy with presenting a rapidly and fatally aggressive clinical course. The diagnosis of this disease is mainly based on the clinical presentations, pathologic and immunohistochemical features. BPDCN is a highly aggressive disease, its prognosis is very poor, its pathogenesis remans still unclear. A standard treatment protocol for BPDCN has not yet been established.

Effects of human aorta-gonad-mesonephros region stromal cells on inducing differentiation of murine embryonic stem cells into hematopoietic stem/progenitor cells in vitro / 中国实验血液学杂志

This study was aimed to investigate the effect of human aorta-gonad-mesonephros (AGM) region stromal cells on differentiation of murine embryonic stem cells (ESC) into hematopoietic stem cells (HSC) in vitro and to clarify their effect mechanism. E14 murine ESC were induced into embryo body (EB) firstly. Then the EB cells were further co-cultured with the stromal cells from human AGM region, fetal liver (FL) or bone marrow (BM) in Transwell non-contact system. According to the different culture methods, the EB cells were divided into 6 groups including EB control group, AGM group, FL group, BM group, AGM + FL group and AGM + BM group. The induced cells derived from EB were collected for Sca-1(+)/c-Kit(+) cells analysis by flow cytometry and colony forming unit (CFU) assay. The results showed that Sca-1(+)/c-Kit(+) cell proportion of EB cells significantly increased after being induced by different stromal cells (p < 0.01). The AGM + FL group had most Sca-1(+)/c-Kit(+) cells for the positive cell proportion reached (21.96 ± 2.54) % (p < 0.01). The Sca-1(+)/c-Kit(+) cell proportion of AGM + BM group was much high than that of BM group too (p < 0.01). The EB control group showed CFU amount less than any other groups, while the CFU amount of AGM + FL, AGM + BM groups were higher, especially in the AGM + FL group (p < 0.01). It is concluded that the human AGM region stromal cells may help to maintain certain number of primitive HSC with high proliferation potential. Human AGM region, FL or BM stromal cells, applied in sequential orders, can significantly expand in vitro the primitive hematopoietic stem/progenitor cells derived from ESC.

Sequentially inducting murine embryonic stem cells into hematopoietic stem cells in vitro by hematopoietic development procedure for reconstitution of hematopoiesis in vivo / 中国实验血液学杂志

This study was purposed to directly induce murine embryonic stem cells (ESC) into hematopoietic stem cells (HSC) by simulating the spatial and temporal hematopoietic microenvironment changes in embryonic development, and to investigate the function of in vivo hematopoietic reconstitution of these HSC. E14 ESC were induced into embryoid body (EB) firstly. Then the cells from EB were further co-cultured with human aorta-gonad-mesonephros (AGM) region, fetal liver (FL) and bone marrow (BM) stromal cells in Transwell non-contact system in sequential orders. After 6 days of each co-cultured stage, the induced cells derived from EB were collected to analyze the Sca-1(+)c-Kit(+) cells by flow cytometry, check teratoma formation and transplant to BALB/C female mice exposed to lethal dose (60)Co γ-ray. The recipient mice were divided randomly into 5 groups: AGM, AGM + FL, AGM + FL + BM, irradiation control and normal control groups. The survival rates, hematopoietic reconstitution and engraftment of donor cells in the different groups were monitored. The results showed that Sca-1(+)c-Kit(+) cell level in EB cells co-cultured with human AGM region and FL stromal cells reached to peak value (21.96 ± 2.54)%. Teratomas could be found in NOD-SCID mice after subcutaneous injection of EB cells co-cultured with human AGM region stromal cells, while there was no teratoma in the mice after subcutaneous injection of EB cells induced by human AGM region and FL stromal cells. The recipients in AGM group and irradiation control group all died. The survival rate was 77.8% in AGM+FL group, and 66.7% in AGM+FL+BM group. The peripheral blood cell count was near normal at day 21 after transplantation, and Sry gene copies from donor could be detected in recipient mice of these two groups. It is concluded that sequentially inductive system with feeder cells from human AGM region, fetal liver and bone marrow simulating embryonic defined hematopoiesis procedures can enhance the directed differentiation of ESC into HSC which can safely reconstitute hematopoiesis in vivo.

Influence of FcγRIIIa polymorphism on rituximab-dependent NK cell-mediated cytotoxicity to Raji cells / 中国实验血液学杂志

Fcgamma receptor IIIa (FcγRIIIa) polymorphisms is considered to influence clinical response to therapeutic monoclonal antibody (McAb) in cancer, most people believe it can affect McAb binding, and McAb-dependent NK cell-mediated cytotoxicity. This study was purposed to determine the difference of antibody-dependent cell-mediated cytotoxicity (ADCC) effects mediated by different FcγRIIIa NK cells. The FcγRIIIa genotypes were detected by nest-PCR, the target cells (Raji cells) were stained with 5- (and 6-) carboxyfluorescein diacetate succinimidyl ester (CFSE), cultured with effector cells with different FcγRIIIa genotypes, and finally stained with propidium iodide (PI); the CD20 expression of Raji cells were tested by flow cytometry and cytotoxic index was calculated as well. The results indicated that the ADCC cytotoxic indexes of NK cells with FcγRIIIa-158V/V and FcγRIIIa-158V/F were 69.05±2.38% and 39.63±3.86% respectively, as compared with NK cells with FcγRIIIa158 V/V, ADCC effect of NK cells with FcγRIIIa-158 on Raji cells was obviously weakened with significant difference (p<0.05). It is concluded that FcγRIIIa polymorphism can influence ADCC activity of NK cells, ADCC activity of NK cells with FcγRIIIa-158V/V is higher than that of NK cells with FcγRIIIa-158V/F.

Fcγ receptorIIIa polymorphism in healthy children and those with hematological malignancies / 中国实验血液学杂志

Fcγ receptorIIIa (FcγRIIIa) polymorphism was considered to influence clinical response to therapeutic monoclonal antibody (MAb) against cancer, which is suggested to affect MAb binding and MAb-dependent NK cell-mediated cytotoxicity. The purpose of this study was to examine the FcγRIIIa gene polymorphisms in healthy children and in children with hematological malignancy, and to explore its possible effect on MAb in children with hematological malignancies. 43 healthy children (H) and 20 pediatric patients with hematological malignancies (HM) were enrolled in this study. DNA was isolated from peripheral blood, and then nest-polymerase chain reaction-restriction fragment length polymorphism (nest-PCR and PCR-RFLP) was used to determine the FcγRIIIa-158 genotypes in each groups of subject, digested fragments were subjected to electrophoresis on 15% PAGE. The results showed that there were a higher frequencies of FcγRIIIa-158V/F in H and HM group (72.1% and 75.0% respectively), the frequencies of FcγRIIIa-158V/V were 27.9% and 25.0% in H and HM group respectively, but there was no FcγRIIIa-158F/F in the two groups. No significant difference in distribution of the FcγRIIIa-158 genotype was found between HM and H groups (p > 0.05). It is concluded that FcγRIIIa-158V/F is more frequent, while FcγRIIIa-158V/V is less, but FcγRIIIa-158F/F is very rare in both groups. No significant difference of FcγRIIIa polymorphism distribution is found between healthy and hematological malignancy groups.

Distribution and interaction of bone marrow mesenchymal stem cells and cord blood CIK/NK cells infused via different ways at different time periods in NOD/SCID mice / 中国实验血液学杂志

The study was aimed to explore the distribution and interaction mechanism of human bone marrow mesenchymal stem cells (MSC) and cord blood cytokine-induced killer (CIK)/natural killer (NK) cells infused via different ways at different times in NOD/SCID mice. 5 microl 1, 1'-dioctadecyl-3, 3, 3', 3'-tetramethylindocarbocyanine perchlorate (DiI) dye(red) was added in suspension of MSC per ml, and 1 microl carboxyfluorescein diacetate, succinimidyl ester(CFDA SE) dye(green) was added in suspension of CIK/NK cells per ml. The amounts of MSC and CIK/NK cells infused in each 6 NOD/SCID mouse were 1 x 10(6) (0.1 ml) and 1 x 10(7) (0.1 ml) respectively. All mice were divided into 4 groups, each group consisted of 6 mice. Group A: MSC (intravenous infusion, iv) + CIK/NK cells (iv) at the same time, group B: MSC (iv) + CIK/NK cells (iv) at 48 hours after infusion of MSC; group C: MSC (intramedullary infusion, im) + CIK/NK cells (iv) at the same time; group D: MSC (im) + CIK/NK cells (iv) at 48 hours after infusion of MSC. 3 NOD/SCID mice were sacrificed per batch at 24 hours and 48 hours after infused CIK/NK cells. Frozen sections of liver, spleen, lung and kidney were prepared, and then followed by counting the amounts of red and green fluorescence cells under fluorescence microscope, and calculating the ratio of MSC to CIK/NK cells for reflecting the interaction of MSC and CIK/NK cells in mice, and for showing the suppressive intensity of MSCs on CIK/NK cells. The results showed that the sums of average ratios of MSC to CIK/NK cells in lung, liver and spleen of group A and B were higher than that in group C and D at 24 hours and 48 hours respectively after infusing CIK/NK cells. The sum of average ratios of MSC to CIK/NK cells in group A was slightly higher than that in group B at 24 hours and 48 hours after infusing CIK/NK cells, but there was no significant difference between them. The sum of average ratios of MSC to CIK/NK cells in lung, liver and spleen in group C was slightly lower than that in group D at 24 hours after infusing CIK/NK cells, but reversed at 48 hours later and there was no significant difference between them. The sums of average ratios of MSC to CIK/NK cells in lung, liver and spleen in group A, B, C and D were all higher than those in kidney at 24 and 48 hours respectively after infusing CIK/NK cells. It is concluded, the MSC and CIK/NK cells may interact if they are infused via the same way and at the same time, the location where the suppression of MSC on CIK/NK cells occur in vivo may be reticulo-endothelial systems in lungs and livers.

Effect of mesenchymal stem cells on expression of CD69 in cord blood CIK/NK cells and quantity ratio of T regulatory cells in CIK/NK cell culture / 中国实验血液学杂志

This study was purposed to explore the effect of bone marrow derived mesenchymal stem cells (MSCs) on the expression of CD69 on cytokine-induced killer (CIK)/natural killer (NK) cells derived from cord blood and on the quantity ratio of CD4+CD25+ T regulatory cells in CIK/NK cell culture system using Transwell non-contact cell culture system. The experiments were divided into two groups: Transwell non-contact culture and mixture culture. The ratio of MSC to CIK/ NK cells was 1:20, 1:50 and 1:100. In mixture culture groups, MSC and CIK/NK cells were co-cultured by together contact as the same ratio of Transwell non-contact culture groups. The expression of CD69 on CIK/NK cells, as well as the quantity ratio of CD4+CD25+ T regulatory cells in CIK/NK cell culture were evaluated by flow cytometry. The results showed that the expression of CD69 on CIK/NK cells in experimental groups were significantly lower than that in control group (p<0.001). As to Transwell groups, CD69 expression on the CIK/NK cells at 1:20 ratio of MSC and CIK/NK was significantly lower than that at 1:50 and 1:100 ratio. There were no differences in the expression of CD69 on CIK cells in mixture groups with various MSC ratios, whereas the expression of CD69 on NK cells at 1:20 ratio was significantly lower than that at 1:50 and 1:100. The quantity ratio of CD4+CD25+ cells in CIK/NK cell culture system of experimental groups with MSC co-culture was significantly higher than that in control. As to Transwell groups, the ratio of CD4+CD25+ cells in CIK/NK cell culture system at 1:20 and 1:50 was significantly higher than that at 1:100. The quantity ratio of CD4+CD25+ cells in CIK/NK cell culture system showed significant differences in various mixture groups. As to 1:20 ratio the amount of CD4+CD25+ cells in CIK/NK cell culture system of mixture groups was significantly higher than that in Transwell groups, while there were no differences of the quantity ratio of CD4+CD25+ cells in CIK/NK cell culture at 1:50 and 1:100. It is concluded that either by non-contact Transwell or mixed co-culture, the MSC can suppress the activation of allogeneic CB-CIK/NK cells, which maybe relate to up-regulating the ratio of CD4+CD25+ T regulatory cells in CIK/NK cell culture system in dose-dependent manner.

Unrelated allogeneic umbilical cord blood transplantation: present status, problems and countermeasures / 中国实验血液学杂志

As unrelated allogeneic umbilical cord blood transplantation (UCBT) has been developed for 20 years already since 1988, more than ten thousands cases have cumulatively undergone UCBT over the world. A huge number of clinical data confirmed that UCBT had unique characters with low rate of severe GVHD. The efficacy and data on TRM, relapse and EFS of allogeneic UCBT with HLA 0-1 mismatched are similar to those in HLA matched BMT. UCBT has become the optimal choice for source of hematopoietic stem cells for allogeneic stem cell transplant especially when HLA-matched or haploidentical donors are not available in time. In most developed countries, unrelated allogeneic UCBT developed successively, and in recent years HLA mismatched UCBT with double units performed in adults increased even more rapidly than in children. Another recent trend of UCBT has been extending to treat some non-malignant but refractory diseases in pediatrics, such as severe combined immunodeficiency, thalassemia major, bone marrow failure syndrome and metabolic disorders. The clinical successful practice of double units for cord blood transplantation inspires to ponder over questions remaining mystery. What is the conflict like between two mismatched donor cells in vivo, which does not spoil the whole transplantation but enable the patient to be engrafted successfully without any increment of the dosage by the sum of two doses together? How can they both be taken at the same time firstly by the recipient, but why does only one predominate later? What are the factors enable the donor cells of the winner to sustain? With the references of the international experiences, how to solve the clinical encountered problems, perspective of unrelated allogeneic UCBT and proper strategies to be enacted are reviewed.

Relationship between cellular immune function during conditioning and graft rejection in patients with beta-thalassemia major / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the relationship between cell-mediated immune function during conditioning and graft rejection in patients with beta-thalassemia major.</p><p><b>METHODS</b>Allogeneic hematopoietic stem cell transplantation was performed in 25 children with beta-thalassemia major and 11 with acute leukemia group. The percentages of T lymphocytes and natural killer (NK) cells in peripheral blood of these patients were detected with dual color immunofluorescence on day -10 (before conditioning) and day -5 (after conditioning), and the relationship between the cellular immune function and graft rejection was analyzed.</p><p><b>RESULTS</b>All the patients with acute leukemia showed engraftment. The rate of graft rejection was 34.8% in the patients with beta-thalassemia major. Compared with the leukemic patients, the patients with beta-thalassemia showed significantly increased percentage of CD3(+)CD8(+) T lymphocytes before and after the conditioning (P<0.05). The percentage of CD3(-)CD56(+) NK cells increased significantly in patients with beta-thalassemia major after the conditioning (P<0.05), but decreased markedly after conditioning in the leukemic patients (P<0.05). In patients with beta-thalassemia major and graft rejection, the CD3(-)CD56(+) cell phenotype was predominant after conditioning but remained unchanged in those with engraftment.</p><p><b>CONCLUSION</b>CD3(-)CD56(+) NK cells are probably associated with graft rejection in patients with beta-thalassemia major, and may serve as an index for predicting graft rejection following allogeneic hematopoietic stem cell transplantation.</p>

Biological characteristics of bone marrow-derived mesenchymal stem cells and their relationship with immunosuppressive therapy in children with aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the biological characteristics of bone marrow-derived mesenchymal stem cells (MSC) in children with aplastic anemia (AA) and evaluate the relationship of biological characteristics of MSC with the efficacy of immunosuppressive therapy (IST).</p><p><b>METHODS</b>Bone marrow-derived MSC were cultured and isolated from 29 children with AA and 5 normal controls. Seventeen out of the 29 cases received IST. Surface markers and cell cycle of MSC at passage 3 were analyzed by flow cytometry. The inhibition of lymphocyte proliferation by MSC was evaluated and TGF-beta 1 level in the supernatant of MSC was detected using ELISA.</p><p><b>RESULTS</b>Growth abnormality of MSC was found in 16 children with AA (55%), characterized by deficiency and poor proliferation of MSC, and was frequently seen in patients with severe AA or in patients with more prolonged disease course or in patients with radiation/chemotherapy-induced AA. Surface markers, cell cycle and TGF-beta 1 level in the supernatant of MSC at passage 3 and the inhibition of lymphocyte proliferation by MSC in the AA group were similar to those in the control group. Eight out of nine patients with normal MSC growth achieved complete remission (CR) but only 2 out of 8 patients with abnormal MSC growth achieved CR following IST ( P<0.01).</p><p><b>CONCLUSIONS</b>Bone marrow-derived MSC growth abnormality occurs in most of children with AA. MSC abnormality may affect adversely hematological recovery following IST.</p>

The cytotoxicity of CIK/NK cells stimulated by K562-DC fusion vaccines in NOD/SCID mice model for human erythroleukemia / 中华血液学杂志

<p><b>OBJECTIVES</b>To study the in vivo efficacy and the safety of cord blood derived CIK/NK cells stimulated by K562-dendritic cells (DC) fusion vaccines in NOD/SCID mice model for human erythroleukemia.</p><p><b>METHODS</b>DC and CIK /NK cells were both derived from cord blood mononuclear cells. DC were fused with inactivated K562 leukemia cell by PEG to produce K562-DC fusion vaccines. K562-DC fusion vaccines were co-cultured with CIK/NK cells to prepare K562-DC fusion vaccine stimulated CIK/NK cells. NOD/SCID mice were inoculated with 1 x 10(6) K562 cells. 24 hours later, 1 x 10(7) vaccines stimulated CIK/ NK cells and 1 x 10(7) CIK/NK cells were transfused into the NOD/SCID mice. NOD/SCID mice without inoculation of K562 cells were used as control group. CD13 and CD56 positive cells were assayed by flow cytometry.</p><p><b>RESULTS</b>All the leukemia NOD/SCID mice without therapy died within 39 days, tumor was found in 5 of 8 mice. One of 8 leukemia mice treated with K562-DC fusion vaccines stimulated CIK/NK cells died at the 65th day, the anti-tumor response rate was 87.5%. Two of the leukemia mice treated with CIK/NK cells died at the 56th and 65th day respectively, the anti-tumor response rate was 75%. There was no significant difference in survival time between these two groups, and both survivals were longer than that of the control group. There was no significant difference in CD13 positive cells in the survival mice between these two groups, and both of that were less than that of the control mice. There was no significant difference in CD56 positive cells between the two treated groups and the control group.</p><p><b>CONCLUSIONS</b>Cord blood derived CIK/ NK cells stimulated by inactivated tumor cells retain the cytotoxicity and do not develop tumor in vivo.</p>

Isolation and culture of human embryonic AGM derived HSPCs in hematopoietic culture systems created by AGM stromal cells / 中国实验血液学杂志

This study was purposed to isolate human embryonic AGM derived HSPCs and investigate the effect of AGM stromal cells on AGM-derived HSPCs. Immunohistochemical sections of human AGM tissue were investigated for CD34, Flk-1 and VEGF expression. Human AGM-derived single cells were isolated and seeded onto pre-treated feeder of human AGM stromal cells (hAGMS3 and hAGMS4) by direct contact and non-contact co-culture in Transwell culture system. Growth characteristics of HSPCs with cobblestone area-forming cells (CAFCs) were observed and number of cobblestone area (CA) was counted. Indirect immunofluorescent assay was used to detect CD34 and Flk-1 expression on the surface of suspended cells as well as CAFCs in contact co-culture system. The cells after culture for 2 weeks were collected from both contact and non-contact co-culture systems for CFU assay. The result showed that hematopoietic cells in AGM tissue expressed CD34 and Flk-1. Both of the hematopoietic culture systems could produce CFCs. Nevertheless, direct contact co-culture produced CD34(+)Flk-1(+) CAFC and more CFUs than those from indirect non-contact culture (hAGMS3 system: 1647 +/- 194 vs 389 +/- 31, p < 0.05; hAGMS4 system: 1586 +/- 75 vs 432 +/- 35, p < 0.05). It is concluded that there were CD34(+)Flk-1(+) HSCs in human embryonic AGM region. The hematopoietic co-culture systems composed of AGM-derived HSPCs and AGM stromal cells are successfully established, both direct contact and Transwell non-contact co-culture can expand AGM-derived definitive HSPCs. Cell-cell contact between AGM-derived HSPCs and AGM stromal cells are of most importance to maintain and expand AGM-HSPCs.

BMP-4 and VEGF promote development of hematopoietic stem cells during the embryoid body formation from embryonic stem cells / 中国实验血液学杂志

The objective of this study was to explore the effects of BMP-4 and VEGF on the development of primary hematopoietic stem cells during the differentiation of embryonic stem cells (ESCs) into embryoid body (EB). Murine E14 ESCs were seeded into semisolid methylcellulose-based medium for EB formation. According to added or not cytokines, experiments were divided into: (1) group of spontaneous differentiation without cytokine as control; (2) group of BMP-4 in different concentrations (0, 5, 15, 25 and 50 ng/ml); (3) group of BMP-4 combined with VEGF; (4) group of VEGF alone. EBs were collected on days 3, 6, 9, 12, 15, and the proportion of Flk-1(+) cells were assayed by flow cytometry. The results showed that in the different BMP-4 concentration groups, the proportions of Flk-1(+) cells were significantly different, and it reached the peak values in 25 ng/ml BMP-4 group as 6.51 +/- 1.02% at day 3 and 7.70 +/- 1.12% at day 6 respectively, which were statistically higher than those in control group without-BMP-4 and in 5 ng/ml BMP-4 group (p < 0.05). When BMP-4 was used in combination with VEGF, Flk-1(+) cells went to peak proportion value at day 9 as 27.53 +/- 8.14%, which was statistically higher than that in spontaneous differentiation group as 8.77 +/- 2.35% (p < 0.05) and VEGF treatment group as 11.21 +/- 2.23% (p < 0.05). It is concluded that BMP-4 in combination with VEGF can promote Flk-1(+) cells genesis during EB formation in vitro, which provides experimental evidence for researches on directed differentiation of ESCs into hematopoietic stem cells simulating the microenvironment in vivo.

Analysis of lymphocyte immune abnormality in 52 cases of children idiopathic aplastic anemia / 中国实验血液学杂志

This study was aimed to investigate the characteristics of lymphocyte immune abnormality in children idiopathic aplastic anemia (IAA) in order to explore the immune pathogenesis of childhood IAA. The phenotypes of lymphocytes, the ratios of Th1/Th2 and Tc1/Tc2, the levels of CD25(+) and CD4(+)CD25(+) T lymphocytes in peripheral blood of IAA patients were measured at the onset of disease by flow cytometry and were compared with that in normal controls. The influences of those immunological indicators on prognosis of IAA were also analyzed. The results showed that there were 40 cases of severe aplastic anemia (SAA) and 12 cases of mild aplastic anemia (MAA). The levels of CD3(+) CD8(+) T cells in SAA group and MAA group were significantly higher than those in controls (p < 0.05). The levels of CD3(+) and CD3(+) CD4(+) T cells in MAA group were lower than that in SAA group (p < 0.05), but there were no difference was compared with control group. No differences of the levels of CD3(-)CD19(+) T cells were between the both SAA and MAA groups and the control group. The levels of CD3(-)CD56(+) T cells in SAA group and MAA groups were lower significantly than that in control group. As compared to control group, the levels of Th1 and Tc1 in SAA group and MAA groups increased significantly (p < 0.05), and the ratios of Th1/Th2 and Tc1/Tc2 in SAA group and MAA groups increased significantly (p < 0.05). The level of Th2 increased in SAA group. As compared to MAA group, the levels of Th1 and Tc1 and the ratios of Th1/Th2 and Tc1/Tc2 in SAA group increased significantly (p < 0.05). The levels of CD25(+) T lymphocyte in SAA group and MAA group increased significantly (p < 0.05), and were higher than that in normal controls, but levels of CD4(+)CD25(+) T lymphocyte and ratio of CD4(+)CD25(+)/CD4(+) in SAA group and MAA group had no significant difference. It is concluded that the abnormal lymphocyte immune function exist in the onset of childhood IAA. The polarization of Th1/Th2 and Tc1/Tc2 shifts to Th1 and Tc1 cells. These changes closely relate to severity of the disease. There is high level of CD25(+) T lymphocyte in children IAA. These changes reveal that abnormality of immune function plays an important role at the onset of childhood idiopathic aplastic anemia.

Effect of intra-bone marrow infusion of allogeneic mesenchymal stem cells on reconstruction of marrow mesenchymal stem cells in rat HSCT models / 中国实验血液学杂志

This study was aimed to investigate the effect of intra-bone marrow (IBM) injection of allogeneic mesenchymal stem cells (MSCs) on reconstruction of bone marrow MSCs (BM-MSCs) in rats that received hematopoietic stem cell transplantation (HSCT), and to detect the donor MSCs in the hosts for clarifying the effect mechanism of donor MSCs. Wistar female rats conditioned with lethal dose 60Co gamma-ray irradiation were co-transplanted with F344 female fetal and neonatal peripheral blood (FNPB) and BrdU-labeled MSCs separated from bone marrow mononuclear cells of F344 male rats. The donor MSCs were infused by IBM injection in bilateral tibia or intravenous injection (IV), while the FNPB were all via IBM route. The survival rate, engraftment level of HSCs and recovery of BM-MSCs of recipients were monitored. The ratio of BrdU-labeled MSCs in recipient rats was calculated by immunofluorescence assay (IFA) and the Y chromosomes were examined by PCR. The results showed that the recipient rats of the two co-transplantation groups were all alive at day 60 after transplantation. There was no significant difference between these two groups on the survival rates or the engraftment levels of HSCs, but each of them was much better than that of the FNPB group. At day 30 after transplantation, the proliferation ability of recipients' BM-MSCs was still below normal, while that of the FNPB (IBM)+MSC (IBM) group was the best of all the experiment groups (p<0.01). At 60 days, the donor MSCs coexisted with host MSCs in only a few recipient rats examined by IFA, while the Y chromosomes could be detected in all the recipient rats in the two cotransplantation groups. It is concluded that the infusion of allogeneic MSCs can accelerate the recovery of HSCT recipients' BM-MSCs. The IBM route is safe and more effective than intravenous infusion.

In Vitro Generation of Hematopoietic Stem Cells from Embryonic Stem Cell to Reconstruct Hematopoiesis / 实用儿科临床杂志

Objective To search for a good method for generation of hematopoietic stem cells (HSC) by embryonic stem cells (ESC),and to investigate the potential of HSC derived from ESC to reconstruct hematopoiesis in vivo.Methods Using a three-step method to induce a mice ESC line, E14.1-into HSC.And identifying HSC by flow cytometry analysis cell markers with CD34 +/Sca-1+, then HSC (1×109L-1)from ESC differentiation were injected into severe combined immunodefieency (SCID) mice for observing teratoma formation.To validate function of HSC by colonngenic cells assay and to reconstitute the hematopoiesis in lethally irradiated mice.Results Combining to use more hematopoietic stimulating factor to availably promote the El4.1 cell into embryoid body (EBs) with abundant hematopoietic progenitors.EBs were induced after 14 day to fast differentiate for HSC with peak percentages of CD34+/Sca-1+ cells reached to (13.72±2.07)%.To harvested ceils from EBs by day 14 for second -step HSC differentiation, percent of CD34+/Sca-1+ cells rise to(24.62±2.50) % after day 16 induction.Cloning forming units (CFU) analysis showed that more Erythro -myeloid cloning generation was observed at this period.Cells obtained in the second step are subsequently plated on monolayer of mice bone marrow stromal cells, in the presence of TPO, FLt3 ligand and superoatant of mice fetal liver stromal cells, cultured for additional 15 days, followed fast expansion of CD34+/Sca-1+ to maximally (58.64±4.20 ) % with more CFU-E, CFU-GM and CFU-GEMM population.Wright-Giemsa stain showed that its had the character of hematopoietic progenitors.Cells from the third-step were injected into SCID mice, but no teratomas were recovered in 2 mices after 6 weeks.Positive selection of CD34+/Sca-1+ cells by magnetic sorting from the third - step differentiation were transplanted into 7 lethally irradiated female mice while predominant hematopoietic reconstitution were observed in 10 days after transplantation, with 71.4% successful engraftment rate.And 3 recipients showed that the cell population of the peripheral blood leukocytes,red cells, hemoglobin approached normal index at 40 days after transplant, hut followed relative'slow renew in platelet count.Survival rate of transplant group is 43.0%, compared to 100% mortality in control mice.Karyotyping assays confirmed female mice with XY.Conclusions The results showed that the three-step differentiation and the culture conditions described here good support differentiation of ESC into HSC.HSC derived from ESC were safe without teratomas formation in body, and its can reconstruct hematopoiesis.

Establishment and characterization of two new human embryonic stem cell lines, SYSU-1 and SYSU-2 / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human embryonic stem cells can propagate indefinitely in vitro and are able to differentiate into derivatives of all three embryonic germ layers. The excitement surrounding human embryonic stem cells lies largely in their potential to produce specialized cells that can be used for transplant therapies. However, further investigation requires additional cell lines with varying genetic background. Therefore, efforts to derive and establish more human embryonic stem cell lines are highly warranted.</p><p><b>METHODS</b>Surplus embryos (blastocysts) from donors were used to isolate the inner cell mass by immunosurgery. All cells were cultured continuously on irradiated murine embryonic fibroblasts feed layer and likely human embryonic stem cell colonies were subsequently characterized by cell surface marker staining, karyotyping and teratoma formation.</p><p><b>RESULTS</b>Two human embryonic stem cell lines (SYSU-1 and SYSU-2) were established from surplus embryos. The two lines express several pluripotency markers including alkaline phosphatase, SSEA-4, Tra-1-60, Oct-4, Nanog and Rex-1. They remain in undifferentiated state with normal karyotype after prolonged passages and can form embryoid bodies in vitro and teratoma in vivo.</p><p><b>CONCLUSION</b>Two new human embryonic stem cell lines have been established from surplus embryos. They can be used to understand selfrenewal and differentiating mechanisms and provide more choices for regenerative medicine.</p>

Expression of transcription factors T-bet/GATA-3 mRNA and its effect on Tc1/Tc2 balance in asthmatic children / 中华儿科杂志

<p><b>OBJECTIVE</b>In contrast to CD(4)(+) helper T-lymphocytes (T(H)), little is known about the transcriptional regulation of CD(8)(+) cytotoxic T-lymphocytes (Tc) and its role in the pathogenesis of asthma is unclear. This study was conducted to investigate the effect of T-bet and GATA-3 mRNA expression on profiles of type 1 and type 2 cytotoxic T lymphocytes in asthmatic children.</p><p><b>METHOD</b>Totally 38 asthmatic children, including acute attack group composed of 20 cases (age 3 - 13 years, mean 6.2 +/- 2.9), remission group with 18 cases (age 3 - 12 years, mean 6.1 +/- 2.5) and 20 healthy control children (age 3 - 12, 6.9 +/- 2.7) were recruited in this study from Sep. 2005 to Mar. 2006. The mRNA expression of T-bet and GATA-3 in the peripheral blood mononuclear cells were detected by using semi-quantitative PCR and Tc1, Tc2 cell numbers by flow cytometry analysis system.</p><p><b>RESULT</b>T-bet mRNA in asthmatic children was lower than that in control group and lower in attack stage than in remission stage (0.14 +/- 0.04, 0.21 +/- 0.03, 0.28 +/- 0.03, P < 0.05). In contrast, GATA-3 mRNA was higher in asthmatic children than in control group and higher in attack stage than in remission stage (0.49 +/- 0.09, 0.44 +/- 0.08, 0.37 +/- 0.04, P < 0.05). It was shown that Tc1 percentage was lower in asthmatic children than those of control group and lower in attack stage than those of remission stage (6.6 +/- 2.4, 14.2 +/- 4.3, 31.2 +/- 3.8, P < 0.05). Tc2 percentage in asthmatic children was higher than that of control group and higher in attack stage than that of remission stage (10.0 +/- 4.2, 5.4 +/- 2.2, 3.5 +/- 1.1, P < 0.05). Spearman correlation analysis revealed that T-bet mRNA was positively correlated with Tc1 percentage (r = 0.704) and negatively correlated with Tc2 percentage (r = -0.629). GATA3 mRNA was negatively correlated with Tc1 percentage (r = -0.612) and positively correlated with Tc2 percentage (r = 0.673). The T-bet/GATA-3 mRNA ratio was positively correlated with Tc1 percentage (r = 0.731) and Tc1/Tc2 (r = 0.773), while negatively correlated with Tc2 percentage (r = -0.642).</p><p><b>CONCLUSION</b>The imbalance of T-bet/GATA-3 mRNA expression is closely correlated with skewed Tc2 dominance in asthmatic children.</p>

Experiment study of efficacy on hematopoietic reconstitution and GVHD prophylaxis after mesenchymal cell infused by intra-bone marrow cavity or intravenous in rat BMT models / 中华血液学杂志

<p><b>OBJECTIVE</b>To observe the in vivo distribution of mesenchymal stem cells (MSCs) after administrated by intra-bone marrow (IBM) or intravenous (i.v.), and compare the effects on hematopoiesis reconstitution and GVHD in rat BMT models.</p><p><b>METHODS</b>(1) MSCs from male Wistar rats marked with CFSE were injected into the bone marrow cavity (IBM) or the vein (i.v.) of recipient rats, and observed the distribution of MSCs in vivo. (2) Allogeneic BMT model of Fischer344 rats (RT1A(1)) to Wistar rats (RT1A(u)) was established. The recipient rats were exposed to 8 Gy of gamma irradiation 1 day before transplantation. The 6 groups were (1) IBM group [IBM-injection of MSCs + IV-injection of bone marrow cells (BMC)]; (2) IV group (i.v.-injection of MSCs (i.v.) + i.v.-injection of BMC); (3) BMT group (only i.v.-injection of BMC); (4) MSCs control group (only i.v.-injection of MSC); (5) normal control group and (6) irradiation control group.</p><p><b>RESULTS</b>(1) After i.v.-injection, large numbers of the MSCs lodged in lungs while small numbers in the peripheral blood, liver, thymus and spleen, and a few marked MSCs could be seen in bone marrow. After IBM injection, most cells distributed in long bones and those lungs were less than that in i.v. group. (2) Co-transplantation of MSCs (IBM/IV) could accelerate the recovery of hematopoiesis, including the recovery of WBC, hemoglobin and platelet, and in IBM-injection was more effective in the recovery of hematopoiesis than that in i.v. group. (3) Incidence rate of GVHD in BMT group was 42% (3/7), and no GVHD occurred in co-transplantation groups. (4) Recovery of CFU-Mix and CFU-MSCs could be seen at 21st and 30th day after transplantation in co-transplantation groups, and IBM-injection was more effective than i.v.-injection.</p><p><b>CONCLUSION</b>(1) IBM-injection results in most MSCs distributed in long bones. (2) MSCs improve the survival rate after BMT. (3) Co-transplantation of MSCs accelerates the recovery of hematopoiesis and reduces the morbidity of GVHD. (4) MSC promotes reconstitution of hematopoietic cells and bone marrow MSCs in recipient rates and the effects of MSCs administrated via IBM is more effective than via i.v.</p>