Cytotoxic effect of IL-2/IL-15 stimulated cord blood derived NK cells on K562/Jurkat cell lines / 中国实验血液学杂志

The aim of this study was to explore the cytotoxicity of fresh cord blood(CB) NK cells and the influence of IL-12 and IL-15 on activity of the NK cells killing K562 and Jurkat cells lines. The NK cells were isolated from cord blood by depleting CD3(+) cells and then enriching CD56(+) cells using sorting with immunomagnetic beads. The experiment was divided into 3 groups: group A (fresh CB-NK cells without cytokines), group B (CB-NK cells cultured by IL-2) and group C (CB-NK cells cultured by IL-2 and IL-15). The purity of NK cells was determined by flow cytometry; the cytotoxity of fresh and different cytokine-treated CB-NK cells on K562 and Jurkat cell lines was detected by LDH release test. The results showed that the purity of NK cells before and after sorting was 14.88 ± 9.2% and 92.39 ± 0.8% respectively. After culture for 3 days, NK-forming colony amounts in group B and group C were 148.60 ± 13.0 and 831.80 ± 23.0 respectively, the comparison between group B and group C showed the significant difference (p < 0.05). The cytotoxicities of NK cells in group A, B and C on K562 and Jurkat cell lines were 27.76 ± 8.8%, 61.90 ± 9.1% and 87.62 ± 3.7%; 29.32 ± 2.5%, 69.43 ± 4.4% and 92.95 ± 3.2% respectively, the difference was significant (p < 0.05). It is concluded that the fresh isolated CB-NK cells show low cytotoxic activity. After stimulated with IL-2 or IL-2 plus IL15, cytotoxicity of CB-NK cells increases obviously, the effect of IL-2 plus IL-15 is much better than IL-2 alone for promoting the growth and enhancing the cytotoxicity of CB-NK cells.

Expression of perforin in cord blood NK cells after IL-2/IL-15 stimulation and its relation with cytotoxicity / 中国实验血液学杂志

This study was aimed to investigate the expression level of perforin in cord blood NK cells and the relation of perforin expression after IL-2, IL-15 stimulation to cytotoxicity of NK cells. NK cells were isolated from cord blood MNC by depleting CD3(+) cells and then enriching CD56(+) cells using immunomagnetic separation (CD3 and CD56 cell isolation kit, autoMACS, miltenyi). The purity was analysed by flow cytometry. According to the different combination of cytokines, there were two groups: group A (IL-2) and group B (IL-2 + IL-15). The cytotoxicity and perforin expression rate of fresh and different cultured CB-NK cells against K562/Jurkat cell lines were estimated by LDH release test (cytotoxic 96 non-radioactive cytotoxicity assay). The results showed that the purity of NK cells after separation was more than 90%. The cytotoxicity towards both tumor lines in group B was higher than that in group A (p < 0.05), and cytotoxicity in group A was higher than that of fresh NK cells (p < 0.05). Perforin expression rate of group A (84.55%) was higher than that of fresh NK cells (67.21%) (p < 0.05), and there was no significant difference between group A and B (84.55% versus 87.22%) Cytotoxic activity of CB-NK cells was positively correlated with perforin expression rate (r = 0.886, p < 0.05). It is concluded that IL-2 can enhance cytotoxicity of CB/BM-NK cells by increasing the perforin expression.

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.

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.

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.

Effect of the serum panel reactive antibody on proliferation and differentiation of cord blood CD34+ cells in vitro / 中华儿科杂志

<p><b>OBJECTIVE</b>The low rate of engraftment in children with beta-thalassemia has seriously restricted the popularity of the hematopoietic stem cell transplantation (HSCT). Panel reactive antibody (PRA) has been regarded as one of the important factors for the success of kidney transplantation. Poly-transfusion before transplantation is associated with the production of PRA. Also PRA is produced in the children with beta-thalassemia major who need poly-transfusion for life. PRA might be one of factors inducing the low rate of engraftment in children with beta-thalassemia. This study focused on observing the effect of PRA on the proliferation, differentiation, apoptosis and necrosis of cord blood CD34(+) cells in vitro by incubating the cord blood CD34(+) cells with serum containing PRA.</p><p><b>METHOD</b>Seven samples of cord blood were collected and the HLA typing for every sample was done. Seven sera positive for PRA and seven negative sera were selected respectively. Mononuclear cells (MNCs) were obtained by Ficoll-Hypaque density gradient centrifugation. CD34(+) cells were isolated from MNCs by positive selection using an immunomagnetic separation (CD34(+) progenitor cell isolation kit and auto-MACS). The CD34(+) cells of umbilical cord blood were incubated with the serum and complement in the following groups: A (absence of serum), B (presence of PRA positive serum), C (presence of PRA positive serum and complement), D (presence of complement), and E (presence of PRA negative serum). After incubation the samples were centrifuged and the supernatant was collected for LDH detection. At the same time the CD34(+) cells were harvested for assessing the expression of Annexin V and CD95 of the CD34(+) cells by flow cytometry and also for the detection of the DNA synthesis by (3)H-TaR incorporation. Meanwhile the cells were inoculated into the methylcellulose cultural system. The proliferation and hematopoietic potential of the CD34(+) cell of cord blood by the colony formation assay were detected on the day 10.</p><p><b>RESULT</b>The concentration of LDH in group A was (20.71 +/- 2.81) U/L, which was significantly lower than that in group B (64.28 +/- 5.12) U/L and group C (84.29 +/- 4.99) U/L. The concentration of LDH in group B was significantly lower than that in group C, while there were no significant differences in the concentration of LDH among groups A, D and E (P > 0.05). The cpm in group A was (22 629 +/- 3288), which was significantly higher than that in group B (4598 +/- 2178) and group C (1626 +/- 1192). And the cpm in group B was significantly higher than that in group C. There were no significant differences in the cpm among groups A, D and E (P > 0.05). On day 10 of culture, the total colonies, granulocyte-macrophage colony forming unit (CFU-GM), mixed colony forming unit (CFU-GEMM) and erythroid burst colony forming unit (BFU-E) in group A were significantly higher than that in group B and C. The total colonies, CFU-GM and CFU-GEMM in group B were significantly higher than those in group C. No significant differences were found in the total colonies, CFU-GM, CFU-GEMM and BFU-E among groups A, D and E (P > 0.05). There were no statistically significant differences in the CD95 and Annexin V expression among all the groups (P > 0.05).</p><p><b>CONCLUSION</b>PRA could impair the membrane, decrease the DNA synthesis, and inhibit the colony formation of CD34(+) cord blood cells, which could be strengthened by the presence of the complement at the given concentration in our study. PRA had no significant influence on the apoptosis of CD34(+) cells in vitro.</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>

Expression of BMP-4 in stromal cells in vitro derived from human aorta-gonad-mesonephros region / 中国实验血液学杂志

The objective of this study was to investigate the expression of BMP-4 in stromal cells in vitro derived from human aorta-gonad-mesonephros (AGM) region. Stromal cells derived from human AGM region (hAGM S1-S5) and fibroblasts derived from human fetal trunk (hFT) were cultured in vitro. RT-PCR was used to analyze the expression of BMP-4 in hAGM S1-S5 stromal cells at mRNA level. And BMP-4 level was detected in the supernatant of hAGM S1-S5 stromal cells by ELISA assay. hFT cells were used as control group. The results showed that the heterogenous hAGM S1-S5 stromal cells displyed shapes of fibroblast-like and endothelial-like cells. hAGM S1-S5 stromal cells expressed BMP-4 mRNA, but fetal trunk fibroblasts (hFT) did not express BMP-4 mRNA. In the supernatant of hAGM S1-S5 cells, BMP-4 could be detected by ELISA assay ana its levels were statistically higher than that in hFT group (p < 0.05), while there was no significant difference between groups of hAGM S1-S5 (p > 0.05). It is concluded that human AGM-derived stromal cells in vitro express BMP-4, and the establishment of a new culture system based on the feeder cells of AGM stroma would promote the differention of embryonic stem cells into hematopoietic stem cells at a high proportion.

Supportive effects of stromal cells from human embryonic aorta-gonad-mesonephros region on umbilical cord blood CD34+ cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the supportive effects of stromal cells from human aorta-gonad-mesonephros (AGM) region on umbilical cord blood CD34+ cells.</p><p><b>METHODS</b>Stromal cells derived from human AGM region (hAGMS1-S5) and fetal trunk fibroblasts (hFf) were cultured on the bottom of 24-well plates as feeder cells. CD34+ cells positively selected from human umbilical cord blood through immunomagnetic beads selection method, were seeded into 24-well plates, and co-cultured for 28d. The number of total nucleated cells (TNC), CD34+ cells, CD34+ CD38- cells, and CFC were counted every week.</p><p><b>RESULTS</b>Stromal cells from human AGM region significantly supported proliferation of the TNC, CD34+ cells, CD34+ CD38- cells and CFC, when compared with hFT and controls without feeder cells (P < 0.05). The TNC increased (25.13 +/- 4.83)-fold (peak value) at day 21 in group of co-culture with AGM stromal cells. CD34 and CD34+ CD38- cells increased (2.68 +/- 0.51)- and (2. 38 +/- 0.45)-fold respectively at day 14 of co-culture. In colony analysis, HPP-CFU increased (2.62 +/- 0.85)-fold at day 14 of co-culture. The supportive effects of human AGM S1-S5 were significantly different, hAGM S3 and S4 were better than hAGM SI, S2, and S5 (P < 0.05).</p><p><b>CONCLUSIONS</b>Human AGM stromal cells S1-S5 could support the maintenance and expansion of umbilical cord blood CD34+ cells in vitro. hAGMS3, S4 cell had better effects on maintaining HSC activity, which would provide model cells and basic data for researches on hematopoiesis mechanism and hematopoietic differentiation of embryonic stem cells.</p>

Ex vivo expansion of megakaryocytic progenitors from mobilized human peripheral blood / 中国实验血液学杂志

This study was aimed to investigate the effect of some culture system composed of various cytokine combinations (TPO, SCF, FL, IL-1, IL-3, IL-6) on ex vivo expansion of megakaryocytic progenitors induced from CD34+ cells of peripheral blood and to seek a optimal cytokine combination and culture time. Mononuclear cells were isolated from mobilized peripheral blood (MPB) by density gradient centrifugation over Ficoll. CD34+ cells were purified by using an immunomagnetic bead separation system. The selected CD34+ cells were seeded in Iscove's modified Kulbecco's medium (IMDM) supplemented with fetal calf serum (FCS) and various kinds of cytokines. After 15 days of culture, the content of CD41+ cells in culture system were determined by flow cytometry, and the number of megakaryocyte colony-forming unit (CFU-MK) was measured simultaneously. The results showed that after definited days of culture, the cytokine combination TPO/FL/IL-6/IL-3 was the most suitable for MPB to obtain high number of MK, and better than any other three groups (P < 0.05). The increase multiple of CD41+ cells was 93.97 +/- 17.27 on day 5 and 131.23 +/- 18.26 on day 10. On day 15, the proportion and the increase multiple of CD41+ cells decreased obviously. The expansion multiples of CFU-MK were 93.33 +/- 10.02 on day 5 and 120.67 +/- 13.01 on day 10, higher than any other groups. It is concluded that TPO/FL/IL-6/IL-3 combination was the best optimal for expansion ex vivo of megakaryocytic progenitors from MPB, and its suitable duration of culture was 10 days; a culture system for expansion ex vivo of megakaryocytic progenitors have been established in this study.

Difference in ex vivo expansion of megakaryocytes derived from umbilical cord blood and peripheral blood / 中华儿科杂志

<p><b>OBJECTIVE</b>Currently, thrombocytopenia is typically observed in patients undergoing hematopioetic stem cell transplantation (HSCT), high-dose chemotherapy or irradiation. Severe thrombocytopenia can cause intestinal and intracranial hemorrhage. To transfuse ex vivo-expanded megakaryocytes (MK) into patients can reinforce the ability of platelet formation and shorten the time of platelet recovery. Therefore it is one of the effective approaches to reduce the danger. The purpose of the present study was to explore the differences in MK expansion between CD(34)(+) stem cells derived from umbilical cord blood (CB) and peripheral blood (PB) and to establish the most optimal culture system.</p><p><b>METHODS</b>Mononuclear cells were isolated by density gradient centrifugation over Ficoll-Hypaque gradient solution. CD(34)(+) cells were isolated by positive selection using an immunomagnetic separation system and the selected CD(34)(+) cells were seeded in Iscove's modified Dulbecco's medium (IMDM) supplemented with fetal calf serum (FCS) and certain kinds of cytokines. After 15 - 17 days of culture, the cells were counted and the content of CD(41)(+) cells was determined by using flow cytometry, and the number of megakaryocyte colony-forming unit (CFU-MK) was simultaneously measured.</p><p><b>RESULTS</b>After the defined days of culture, the cytokine combination of thrombopoietin (TPO) + fetal liver tyrosine kinase ligand (FL) + IL-6 + IL-3 showed to be the most suitable for both PB and CB to obtain high numbers of MK, and to be better than any of the other three groups (P < 0.05). The CD(41)(+) cells from CB were expanded by193 +/- 25 fold on day 14, and those from PB were expanded by 131 +/- 18 fold on day 10. The number of CD(41)(+) cells from both CB and PB decreased.</p><p><b>CONCLUSION</b>For PB and CB, the cytokine combination of TPO + FL + IL-6 + IL-3 is most suitable for obtaining large number of MK and is the best combination for ex vivo MK expansion. MKs from CB seemed to have higher proliferation potential than that from PB, and the optimal culture duration of MK from PB is shorter than that of MK from CB.</p>

Supportive effects of human aorta-gonad-mesonephros-derived stromal cells on umbilical cord blood LTC-IC / 中国实验血液学杂志

The objective of this study was to explore the supportive effects of human aorta-gonad-mesonephros (AGM)-derived stromal cells on human umbilical cord blood long-term culture-initiating cells (LTC-IC). A co-culture system was established with human AGM stromal cells and umbilical cord blood CD34(+) cells. Different stromal cells derived from human AGM region (hAGM S1-S5) were plated on 24-well plates as feeder cells. CD34(+) cells were positively selected from human umbilical cord blood through immunomagnetic bead selection method, seeded on the feeder cells, and co-cultured for 8 weeks. The hematopoietic cells were collected at 5, 6, 7 and 8 weeks for CFC analysis. Frequencies of LTC-IC in umbilical cord blood CD34(+) cells after co-culture with AGM stromal cells were detected through limiting dilute analysis (LDA). The results showed that there was no any hematopoietic CFC in the feeder cell-free culture system after 5 weeks of co-culture. However, in AGM feeder cells culture systems, there were still CFCs after 5 weeks of co-culture, which indicated that human AGM stromal cells could maintain LTC-IC in vitro. In groups of hAGM feeders, hAGMS3 and S4 had better supportive effects than other AGM groups (P < 0.05). The absolute number of LTC-IC in hAGM S3 and S4 culture systems got expansion up to (176 +/- 46)% and (187 +/- 52)% respectively without significant difference between hAGMS3 and S4 (P > 0.05). It is concluded that human AGM stromal cells S1-S5 support the maintenance of umbilical blood LTC-IC in vitro, while hAGMS3 and S4 cells have better effects on maintaining LTC-IC and expansion of LTC-IC.

Mesenchymal stem cells from human cord blood promote engraftment of human umbilical cord blood-derived CD34+ cells in NOD/SCID mice / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore whether the co-transplantation of mesenchymal stem cells (MSC) from human umbilical cord blood (UCB) with UCB-derived CD34(+) cells in NOD/SCID mice could promote engraftment and accelerate hematopoiesis recovery.</p><p><b>METHODS</b>After sublethal irradiated ((60)Co 2.5 Gy), NOD/SCID mice received within 24 hours UCB CD34(+) cells (1 x 10(5) per mouse for low dosage group or 1 x 10(6) per mouse for high dosage group) with or without human UCB-derived MSC (1 x 10(6) per mouse) transplantation by lateral tail vein injection. Peripheral blood cells of transplanted mice were measured for white blood cell count, hemoglobin and platelet count at 10th, 20th, 30th, 40th and 56th day. At the end of 8th week after transplantation, all the alive mice were sacrificed and human derived CD45(+), CD45(+)CD3(+), CD45(+)CD19(+), CD45(+)CD33(+) cells in the bone marrow (BM) were assayed by flow cytometry.</p><p><b>RESULTS</b>(1) In the low dosage group, co-transplantation of MSC significantly raised the engraftment rate (26.02% vs 16.52%) (P < 0.05). (2) The survival rate in high dosage group was 80% for co-transplantation mice and 70% for CD34(+) cells alone transplantation mice. The survival rate in low dosage group was 70% for co-transplantation mice and 50% in CD34(+) cells transplantation mice. (3) In both dosages groups co-transplantation accelerated the hematopoiesis recovery. (4) At the end of 8 weeks after transplantation, in low dosage group, CD45(+)CD33(+) and CD45(+)CD19(+) cells were more in co-transplantation mice than in CD34(+) cells alone transplantation mice, but in high dosage group, the percentage of these two kinds of cells had no difference. In both dosage groups the percentage of CD45(+)CD41a(+) cells were higher in co-transplantation than in transplantation alone mice. CD45(+)CD3(+) cells were low in all groups.</p><p><b>CONCLUSIONS</b>(1) In low dosage transplantation, human UCB MSC could promote human CD34(+) cells engraftment in transplanted mice. (2) Co-transplantation of human UCB MSC and human UCB CD34(+) cells could significantly promote the hematopoiesis reconstitution and improve the survival rate of NOD/SCID mice. (3) MSC could promote human UCB CD34(+) cells to differentiated into B-lymphocytes, granulocyte and megakaryocyte in vivo.</p>

Effects of human umbilical cord blood mesenchymal stem cells on the expansion of CD34+ cells from umbilical cord blood / 中华儿科杂志

<p><b>OBJECTIVE</b>The previous studies indicated that mesenchymal stem cells (MSCs) either from umbilical cord blood (UCB) or from bone marrow (BM) had the same biological characteristics and the function of secreting hematopoietic growth factors (HGFs). The present study aimed to understand the effects of human UCB MSCs on the expansion of CD(34)(+) cells from UCB.</p><p><b>METHODS</b>1. Human UCB CD(34)(+) cells were incubated in the system containing UCB MSCs, HGFs and serum free medium. 2. The surface markers (CD(34)(+), CD(34)(+)CD(38)(-), CD(34)(+)CD(3)(+), CD(34)(+)CD(19)(+), CD(34)(+)CD(33)(+), CD(34)(+)CD(41a)(+)) on expanded UCB cells were examined by flow cytometry on the 6th and 12th days. 3. The expanded and unexpanded cells were cultured in semi-solid culturing system and checked for colony forming units of granulocyte and macrophage (CFU-GM), erythroid burst-forming unit (BFU-E), colony forming units of granulocyte- erythrocyte-megakaryocyte-macrophage (CFU-Mix) and colony forming units of high-proliferative potential (CFU-HPP).</p><p><b>RESULTS</b>1. The expansion folds of CD(34)(+)CD(38)(-) cells from UCB MSCs + HGFs groups on the 6th and 12th days were 159.43 and 436.68, respectively. Interestingly, the percentage of CD(34)(+)CD(38)(-) cells declined in HGFs group after expanding for 12 days, but it rose to 9.98% in the UCB MSCs + HGFs group. 2. Colony forming capacity of expanded UCB cells showed that the folds of CFU-Mix and CFU-HPP of UCB MSCs + HGFs group increased from day 6 to day 12, but the folds decreased in the HGFs group. 3. From day 0 to day 12, CD(34)(+)CD(33)(+) cells and CD(34)(+)CD(41a)(+) cells were amplified gradually, but CD(34)(+)CD(19)(+) and CD(34)(+)CD(3)(+) cells decreased gradually, and in UCB MSCs + HGFs group this phenomenon was more significant than that in HGFs group.</p><p><b>CONCLUSION</b>1. UCB MSCs containing system not only has the ability to expand the primitive HSCs but also has the ability to sustain the proliferation of HSCs. 2. UCB MSCs containing system amplified mainly myeloid and megakaryocytoid progenitor subsets. These may have clinical significance in reducing infection and hemorrhage.</p>

The effect of tumor-dendritic cell fusion vaccines on the cytotoxicity of CIK/NK cells from cord blood / 中华血液学杂志

<p><b>OBJECTIVES</b>To evaluate the effects of K562-dendritic cell (DC) and Raji-DC fusion vaccines on the cytotoxicity of cord blood (CB) derived cytokine-induced killer/natural killer (CIK/NK) cells.</p><p><b>METHODS</b>DC and CIK/NK cells were derived from CB mononuclear cells. CB-DC were fused with inactivated K562 or Raji cells by PEG to form K562 or Raji-DC fusion vaccine. The CIK/NK cells stimulated by different co-culture antigens were three groups: K562-DC or Raji-DC fusion vaccine group, inactivated K562 or Raji plus DC group, and CB-DC alone group. The cytotoxicity of CIK/NK cells stimulated by different co-culture antigens was measured by MTT test.</p><p><b>RESULTS</b>All the antigens used for stimulation could enhance the cytotoxicity of CB-CIK/NK cells, with no specificity difference. At 20:1 effector-target ratio, the cytolytic activities of K562-DC and Raji-DC fusion vaccine groups against Raji cells were (75.44 +/- 4.19)% and (81.33 +/- 4.18)% respectively (P < 0.05); and that of inactivated K562 + DC and Raji + DC group against Raji cells were (73.12 +/- 4.22)% and (80.49 +/- 4.27)%, respectively (P < 0.01). There was no significant difference in the cytotoxicity to K562 cells between the two fusion vaccine groups (P > 0.05). The cytotoxicity of CB-CIK/NK cells immunized by Raji cells was higher than that by K562 cells. In CIK/NK cells co-stimulated by the same tumor antigen, there was no significant difference in the cytotoxicity between DC fusion vaccine group and inactivated cells plus DC group to different tumor cells.</p><p><b>CONCLUSIONS</b>The cytotoxicity of CB-CIK/NK cells to tumor cells was not specific. There was no significant difference in the cytotoxic activity of CB-CIK/NK cells between the DC fusion vaccine group and inactivated cells plus DC group.</p>

Expansion of CIK/NK cells from cord blood by using different combinations of stem cell factor, FLT3 ligand and interleukin 2, 7, 15 in vitro / 中国实验血液学杂志

To explore the efficacy of the different combinations of stem cell factor (SCF), FLT3 ligand (FL) and interleukin (IL) 2, 7, 15 on the induction and expansion of cord blood (CB) derived CIK/ NK cells in vitro, according to the different combinations of cytokines, combinations of cytokines were divided into 3 groups: group A (SCF + IL2 + IL7 + IL15), group B (SCF + FL + IL2 + IL7 + IL15) and group C (IL2 + IL7 + IL15 as control group). At 21 days of culture, the proportion and the expansion rate of CD3(+)CD56(+) CIK cells and CD3(-)CD56(+) NK cells were measured. The results showed that at 21 days in culture, the percentages of CD3(+)CD56(+) CIK cells derived from CB-MNC in group A, B and C were (19.84 +/- 2.93)%, (26.20 +/- 4.05)%, (24.03 +/- 4.99%) and that of NK cells were (49.60 +/- 1.40)%, (51.16 +/- 6.45)% and (30.85 +/- 8.12)%, respectively. The proliferation of CD3(+)CD56(+) CIK cells and CD3(-)CD56(+) NK cells was the most effective in group B (SCF + FL + IL2 + IL7 + IL15). Expansion multiple of CIK cell number increased from 575.81 +/- 221.72 (control) to 796.09 +/- 278.47 with peak value of 1 313, and that of NK cells increased from 30.39 +/- 14.47 (control) to 65.85 +/- 30.83 with peak value of 121.06. In conclusion, a proper cytokines (SCF + FL + IL2 + IL7 + IL15) culture system can effectively induce and expand CB CD3(+)CD56(+) CIK cells and CD3(-)CD56(+) NK cells simultaneously.

Influence of cryopreserved olfactory ensheathing cells transplantation on axonal regeneration in spinal cord of adult rats / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To observe the effects of cryopreserved olfactory ensheathing cells (OECs) transplantation on axonal regeneration and functional recovery following spinal cord injury in adult rats.</p><p><b>METHODS</b>Twenty-four rats were divided into experimental and control groups, each group having 12 rats. The spinal cord injury was established by transecting the spinal cord at T10 level with microsurgery scissors. OECs were purified from SD rat olfactory bulb and cultured in DMEM (Dulbecco's minimum essential medium) and cryopreserved (-120 degree) for two weeks. OECs suspension [(1-1.4)x10(5)/ul] was transplanted into transected spinal cord, while the DMEM solution was injected instead in the control group. At 6 and 12 weeks after transplantation, the rats were evaluated with climbing test and MEP (moter evoked potentials) monitoring. The samples of spinal cord were procured and studied with histological and immunohistochemical stainings.</p><p><b>RESULTS</b>At 6 weeks after transplantation, all of the rats in both transplanted and control groups were paraplegic, and MEPs could not be recorded. Morphology of transplanted OECs was normal, and OECs were interfused with host well. Axons could regrow into gap tissue between the spinal cords. Both OECs and regrown axons were immunoreactive for MBP. No regrown axons were found in the control group. At 12 weeks after transplantation, 2 rats (2/7) had lower extremities muscle contraction, 2 rats (2/7) had hip and/or knee active movement, and MEP of 5 rats (5/7) could be recorded in the calf in the transplantation group. None of the rats (7/7) in the control group had functional improvement, and none had MEPs recorded. In the transplanted group, histological and immunohistochemical methods showed the number of transplanted OECs reduced and some regrown axons had reached the end of transected spinal cord. However, no regrown axons could be seen except scar formation in the control group.</p><p><b>CONCLUSIONS</b>Cryopreserved OECs could integrated with the host and promote regrowing axons across the transected spinal cord ends.</p>

E14 mouse embryonic stem cells differentiate into hepatocyt ESC / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate in vitro methods of inducing mouse embryonic stem cell(s) (ESC) into hepatocytes.</p><p><b>METHODS</b>E14 mouse ESC were cultivated in suspension and plated to form aggregates, the embryoid bodies. They were allowed to outgrow on the plated culture with the stepwise addition of growth factors-- acidic fibroblast growth factor (aFGF), hepatocyte growth factor (HGF) and oncostatin M (OSM) into the culture medium. Morphology was investigated by phase contrast microscopy. Gene expressions of endodermal and liver specific mRNA were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Indocyanine green (ICG) uptake assay and periodic acid-Schiff reaction (PAS) were performed to assess the differentiation and function of the cells.</p><p><b>RESULTS</b>Morphology analysis revealed a difference between ESC-derived hepatic cells and original ESC in that the former showed distinct round or polygonal shapes with clear boundaries, some arranged tightly in cords, while the latter grew in clones without clear boundaries between cells. Those ESC-derived hepatic cells expressed endodermal and liver specific genes mRNA--TTR, AAT, AFP, ALB, G6P and TAT. ICG uptake assay and PAS reaction were positive for those ESC-derived hepatic cells. The ICG positive cells were about 85.1% in number.</p><p><b>CONCLUSION</b>ESC-derived hepatic cells possess characteristics of hepatocytes, which would promise the eventual clinical use of ESC in treating damaged liver tissues.</p>

The experimental study on inducing and expanding T/NK cells from mononuclear cells of human umbilical cord blood / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the most efficient culture system which can induce cord blood (CB)-mononuclear cells (MNC) to differentiate into mature T/NK cells in vitro.</p><p><b>METHODS</b>The CB MNCs were cultured in six culture systems respectively for 4 weeks. The T/NK cell surface phenotypes were analyzed by flow cytometry and the absolute numbers of nucleated cells (NCs) were counted at each time point. Moreover, cell morphology was identified by Giemsa-Wright staining, and cytotoxicity of the cultured cells to K562 and Raji tumor cells was also evaluated by MTT method.</p><p><b>RESULTS</b>Cultured in the cytokine cocktail of SCF + FLT-3L + IL-7 + IL-15 + TNF-alpha + IL-2, the NCs were (20 approximately 26) x 10(6)/ml in numbers at day 22. The percentage of lymphocytes in the NCs and that of CD(3)(+) T cells in the lymphocytes both exceeded 90% at the same time. Most of the CD(3)(+) T cells were CD(3)(+)CD(8)(+) and the percentage of CD(3)(+)CD(4)(+) T cells declined gradually. The percentage of CD(3)(+)CD(56)(+) NKT cells and gamma delta(+)T cells in the lymphocytes arised from lower than 2% to 30% approximately 40% and 10% approximately 15%, respectively. CD(3)(-)CD(56)(+) NK cells were not expanded. The cytotoxic activity of the cultured cells to K562 and Raji cells at an effector:target (E:T) ratio of 50:1 was over 75% and about 32% approximately 65%, respectively.</p><p><b>CONCLUSION</b>The most efficient culture system which can induce CB MNC to differentiate into mature T/NK cells in vitro is the cytokines cocktail of SCF + FLT-3L + IL-7 + IL-15 + TNF-alpha + IL-2, and the optimum culture time is 22 days.</p>