To explore a simple and effective method to determinate the volume of CD34(+) cells in the peripheral blood of donors received drug mobilization for stem cell transplantation by using flow cytometry, the mobilized peripheral blood from donors and 100 micro l fresh whole blood were labeled with monoclonal antibodies Anti-CD34-PE and Anti-CD45-FITC, after lying the red blood cells, and assessed with flow cytometer FL2 (log) vs SSC (log) and FL1 (log) vs SSC (log) were mainly used for analysis windows. The results showed that a level of CD34(+) cells in whole nucleated cells as low as 0.05% - 0.1% can be detected effectively using this method when 10(5) nucleated cells were counted. At day 5 or day 6, the level of CD34(+) cells in most samples of patients reached a peak volume, some of samples and the levels were more than one percent in. It was concluded that CD34(+) cells can be effectively determined by using this method. According to the relative rate of CD34(+) cells, the time to harvest the stem cells in blood can be determined.
Antigens, CD34 ; blood ; Blood Donors ; Flow Cytometry ; methods ; Hematopoietic Stem Cells ; cytology ; Humans

OBJECTIVETo investigate the mRNA expression profiles of megakaryocytes (MKs) from human cord blood CD34+ cells ex vivo expanded using Solexa technique.

METHODSCD34+ Cells were isolated using density gradient centrifugation and magnetic activated cell sorting. Cultures were stimulated with recombinant human thrombopoietin (100 ng/ml). After 12 days, the MKs fraction was separated from the non-MKs fraction using an anti-CD41 monoclonal antibody by immunomagnetic sorting. The mRNA expression of MKs and non-MKs was detected by Solexa sequencing.

RESULTSWe obtained 3 773 147 and 3 533 805 Tags from MKs and non-MKs, respectively. The amounts of unambiguous tags were 3 291 132 and 2 967 947 and those of distinct tags were 197 769 and 245 318. The expression of 1161 genes was up-regulated and that of 902 genes down-regulated. The expression of 2717 tags was up-regulated and that of 1519 tags down-regulated.

CONCLUSIONSMKs and non-MKs have remarkably different mRNA expression profiles. The differential gene-encoded products may be involved in cellular development, adhesion, apoptosis metabolism, intra- and intercellular signal transduction, and immune response. Further studies on this topic may clarify the expression mechanism, signal transduction, and regulation mechanisms.

Antigens, CD34 ; Cells, Cultured ; Fetal Blood ; cytology ; Humans ; Megakaryocytes ; cytology ; metabolism ; RNA, Messenger ; genetics ; Transcriptome

OBJECTIVETo investigate the ability of UCB-derived MSCs to support the expansion of HSCs ex vivo and the possible mechanisms involved in this process.

METHODSHSCs from UCB were co-cultured with UCB-derived MSCs for 14 days, and then the total number of HSCs and colony-forming units (CFU) were detected. Cytokines levels of MSCs supernatant were analyzed using ELISA.

RESULTSThe proliferation rate of HSCs co-cultured with MSCs was significantly higher than that of cultured HSCs alone (P<0.05). Furthermore, the addition of exogenous cytokines to the culture system significantly increased the proliferation rate of HSCs (P<0.05). MSCs had secretion of many cytokines, including GM-CSF, IL-7, IL-8, IL-11, SCF and SDF-1α.

CONCLUSIONUCB-derived MSCs as a feeder layer can be an alternative approach for ex vivo expansion of HSCs, and the cytokines by secreted UCB-MSCs may mediate the supportive role of MSC to HSC proliferation.

Antigens, CD34 ; Cell Proliferation ; Coculture Techniques ; Cytokines ; Fetal Blood ; Humans ; Mesenchymal Stromal Cells

This study was aimed to investigate a beneficial approach for resolving the deficiency of blood source, preventing the infection resulting from blood transfusion and overcoming the knotty match of patients with rare blood group by using massive expansion of erythroid cells from cord blood CD34(+) cells in vitro. The CD34(+) cells from human cord blood were cultured in serum-free medium supplemented with stem cell factor (SCF), interleukin-3 (IL-3) and erythropoietin (EPO) for 1 week, then expansion and differentiation of CD34(+) cells into erythroid cells were supported by co-culture with human mesenchymal stem cells (MSCs) derived from bone marrow for 2 weeks. The results indicated that after culture for 23 days, the expansion multiple of total cell number reached 2.52 x 10(5), and over 95% of these cells were erythroid cells as compared with less than 1% of myelomonocytic (CD14(+) or CD15(+)) cells and megakaryocytic (CD41(+)) cells. However, the culture system without MSC support was significantly disadvantaged both in expansion ability and ratio of erythroid cells when compared with MSC supporting system. It is concluded that the erythroid cells can be produced from CD34(+) cells in large scale by culturing in the system comprised of cytokine sets and MSC feeders, in which MSCs can support the proliferation and differentiation of erythroid cells.
Antigens, CD34 ; Cell Culture Techniques ; methods ; Cell Differentiation ; Fetal Blood ; cytology ; Hematopoietic Stem Cells ; cytology ; Humans

OBJECTIVE: To compare the efficacy of directional erythroid differentiation in different serum free culture systems and to screen the optimal culture systems for inducing the differentiation of umbilical cord blood hematopoietic stem and progenior cells (HSPC) to erythroid cells. METHODS: The CD34 cells from umbilical blood munonuclear cells were sorted by using the magnetic beads, and were inoculated into 3 different of culture systems (system 1, 2 and 3 respectively), to induce erythrold differentiation by 3 stage culture. The living cells were counted in different differentiation stages and were observed by Wright-Giemsa staining; the expression of CD71 and CD235a on cell surface was detected by flow cytometry, the erythroid differentiation pteency was detected via colony-forming test. RESULTS: The ability of system 2 to promote the HSPC proliferation was the strongest, the efficacy of system 3 to promote the erythroid differentiation of HSPC was the most optimal; the proliferation ability of cells cultured in system 2 for 2-15 days all was higher than that of cells cutured in system 1 and 3 (P＜0.05). The flow cytometry detection showed that the expression of CD71 and CD235a on surface of cells cultured in system 3 was the highest, the CD235a percentage on day 15 of differentiation in system 3 was (92.33±3.89)%, that in system 2 was (84.67±3.12)%, while that in system 1 was (72.17±6.83)% (P＜0.05). Cell morplologic detection showed that throid differentiation was accelerated on day 12, the percentage of orthochromatic erythrocytes in system 3 was (67.67±2.08)% which was 10.69 and 25.34 times higher than that in system 2 and 1 respectively (P＜0.05). The colony-forming test showed the ratio of BFU-E in system 3 increased gradually on day 3-9 (r=0.99, P＜0.05), which was significanlly higher than that in system 2 and 1 on day 9 (90.35±5.52% vs 77.06±2.26% and 74.50±3.95%). CONCLUSION Culture system 3 is the most effective serum-free erythroid differentiation system, and the culture system 2 is the most powerful HSPC proliferation system. This study results provide a technical basis for further efficiently increasing and inducing the erythroid proliferation and differentiation of HSPC, and also provide culture system in vitro for the clinical application and basic research.
Antigens, CD34 ; Cell Differentiation ; Cells, Cultured ; Culture Media, Serum-Free ; Erythroid Precursor Cells ; Fetal Blood ; Humans

OBJECTIVE: To screen the antioxidant small molecular compounds with optimal efficiency of expansing the human hematopoietic stem cells (hHSC) In vitro based on antioxidant small molecular compound database of LKT laboratory, and to verify the effects of these compounds on the biological functions of hHSC. METHODS: The umbilial cord blood CD34 cells were enriched by using the MACS beads; the absolute number and percentage of CD34 cells and CD34 CD49f cells were detected by high throughput flow cytometry after culture of hHSC with compounds in vitro for 1 week, the SR1 (1 μmol/L) was used as positive control, the candidate compounds were screened out; then 4 compounds were selected for follow-up experiments by comprehensive evaluation of concentration, safety and expansion efficacy, the optimal used concentrations of selected compounds were determined through the concentration gradient analysis, and CFC short-term colony-forming cell test was performed by using the determined concentration so as to verify the effect of compounds on the self-renewal, multilineage differentiation. RESULTS: Out of 85 antioxidant small molecular compounds, 4 compounds (C2968, D3331, B1753 and B3358) with obvious expansion efficacy for CD34 cells and CD34 CD49f cells were screened out by high throughput flow cytometry; their optimal concentrations of 4 compounds were 0.5 μmol/L for C2968, 1.5 μmol/L for D3331 and 1.5 μmol/L for B1753 and 15 μmol/L for B3358. The CFC assay showed the colony formation number in compound-treated group significantly increased as compared with control group, moreover the self-renewal and multilineage differentiation were maintained. CONCLUSION The antioxidant small molecular compounds C2968 (0.5 μmol/L), D3331 (1.5 μmol/L), B1753 (1.5 μmol/L) and B3358 (1.5 μmol/L) possess good expansion efficacy for hHSC, they can maintain hHSC self-renewal, at the same time ensure the multilineage differentiation potentiality of hHSC.
Antigens, CD34 ; Antioxidants ; Cells, Cultured ; Fetal Blood ; Flow Cytometry ; Hematopoietic Stem Cells ; Humans

The study was purposed to explore the effect of panel reactive antibody (PRA) serum from patients with β-thalassemia on proliferation and apoptosis of the CD34(+)cells from cord blood and its mechanism. CD34(+) cells of umbilical cord blood were incubated with different sera and complement respectively. After incubation, the samples were centrifuged and the supernatants were collected for lactate dehydrogenase (LDH) detection, and the CD34(+) cells were harvested and measured for the apoptosis by flow cytometry with Annexin V/PI. The intracellular DNA synthesis were also quantified by [(3)H]TdR incorporation using liquid scintillation counter. The results showed that concentration of LDH in PRA positive groups was higher as compared with control group, and the DNA synthesis of CD34(+) cells in PRA positive groups were inhibited. There were no differences in the percentage of cell apoptosis and necrosis among different groups. It is concluded that thalassemic serum PRA impairs the cell membrane, inhibits the DNA synthesis, which can be increased by addition of the complement, but PRA had no significant effect on apoptosis of CD34(+) cells.
Antibodies ; blood ; immunology ; Antigens, CD34 ; Apoptosis ; immunology ; Cell Proliferation ; Child ; Fetal Blood ; cytology ; Humans ; beta-Thalassemia ; blood ; immunology ; pathology

The aims of this study were to analyze the composition of umbilical cord blood cells (UCBC), to examine the characteristics of dendritic cells (DC) before and after culture, to search the method of differentiation and increase of DC in vitro and to appraise surface antigen from UCBC. Twelve units of umbilical cord blood were collected from May 2002 to September 2002. Peripheral blood mononuclear cells of 9 cases were collected from healthy adult donors. The nature of UCBC was freshly determined and then UCBC were cultured for 1, 2, 3 and 4 weeks with granulocyte-monocyte colony-stimulating factor (GM-CSF), interleukin 3 (IL-3), recombinant human stem cell factor (SCF) and EPO. Method of flow cytometry was used to determine the number of DC and cell surface antigens before and after culture by using monoclonal antibodies. The monoclonal antibodies included CD4, CD8, CD19, CD34, CD38, CD83, CD1a, CD11c and CDw123. The results showed that amounts of CD34+ progenitors in peripheral blood cells were 0.02 x 10(5)/ml, and amounts of CD34+ progenitors in human UCBC were 0.22 x 10(5)/ml. UCBC cultured for 1, 2, 3 and 4 weeks with GM-CSF, IL-3, EPO and SCF were shown to differentiate into CD1a+ CD11c+ CD83+ CDw123+ DC. Numbers of DC from UCBC remarkably generated in 2-4 weeks and then decreased in number. By culture with cytokines DC increased up to (10.6 - 28.2) x 10(5)/ml in actual numbers. It is concluded that the mononuclear cells of UCB are able to differentiate into CD1a+, CD83+, CD11c+ and CDw123+ DC when UCBC are cultured with proper cytokines of GM-CSF, SCF, EPO and IL-3 for 2-4 weeks. These DCs as antigen presenting cells are possibly effective in cancer immunotherapy.
Antigens, CD1 ; blood ; Antigens, CD34 ; blood ; Blood Cell Count ; Cell Differentiation ; Cytokines ; pharmacology ; Dendritic Cells ; cytology ; Fetal Blood ; cytology ; Humans ; Infant, Newborn

OBJECTIVETo investigate the mode of angiogenesis between highly invasive malignant melanoma and poorly invasive malignant melanoma by immunohistochemistry and periodic acid-Schiff stain (PAS) and to discuss whether the tumor cells in highly invasive malignant melanoma carry vasculogenic mimicry through self-metamorphosis, thus acquiring blood supply to sustain their growth.

METHODSThirty cases of highly invasive malignant melanoma and 30 cases of poorly invasive malignant melanoma were retrieved and reprocessed as tissue microarray for further investigations. The tissue microarray sections were then stained with CD34 and PAS; and the positivity rates were compared.

RESULTSThere was a significant difference between CD34 and PAS staining in highly invasive malignant melanoma (P < 0.01). The difference was not statistically significant in poorly invasive malignant melanoma (P > 0.05).

CONCLUSIONVasculogenic mimicry exists in some cases of highly invasive malignant melanoma. It is possible that the tumor cells can acquire blood supply to sustain growth and metastasize via this mechanism.

Antigens, CD34 ; analysis ; Antigens, Neoplasm ; Humans ; Immunohistochemistry ; Keratins ; analysis ; Melanoma ; blood supply ; metabolism ; pathology ; Melanoma-Specific Antigens ; Neoplasm Proteins ; analysis ; Neovascularization, Pathologic ; metabolism ; pathology

The current study analyzed the data of 4 000 umbilical cord blood (UCB) units collected in Shandong Cord Blood Bank from the end of 1999 to March 2001. The averages of nucleated cells and CD34(+) cells were more than 1.2 x 10(9) and 3.9 x 10(6) per UCB unit respectively, and more than 1.5 x 10(9) nucleated cells per UCB unit were obtained in 768 UCB units. These UCB units are suitable for transplantation in patients with a body weight greater than 40 kg. The analysis of HLA gene frequency showed that A2, A24, A11, B13, B51, DR15, DR7 and DR9 are the common halotypes in Shandong population and similar to those in the other areas of China. 40% patients could search out at least 1 UCB unit with 1 mismatched HLA locus in Shandong Cord Blood Bank.
Antigens, CD34 ; immunology ; Blood Banks ; Blood Preservation ; Cell Count ; China ; Data Interpretation, Statistical ; Fetal Blood ; cytology ; immunology ; metabolism ; Gene Frequency ; HLA-A Antigens ; genetics ; HLA-B Antigens ; genetics ; HLA-DR Antigens ; genetics ; Humans ; Leukocyte Count ; Leukocytes ; cytology ; immunology ; Time Factors