Occurrence and distribution of natural and synthetic progestins, androgens, and estrogens in soils from agricultural production areas in China.

The occurrence of biologically potent sex hormones in agricultural soils is of growing concern due to their ability to disrupt the endocrine systems of aquatic organisms after being transported to surface waters via runoff. This study, therefore, examined the large-scale occurrence of 34 natural and synthetic sex hormones (13 progestins, 16 androgens, and 5 estrogens) in soils from 7 provinces and 1 municipality in China. The target sex hormones were detected in 99.3% of the soil samples, indicating their widespread occurrence in most agricultural areas. Additionally, seven synthetic progestins were detected in soils for the first time. The total concentration of the 34 sex hormones (Σsex hormones) in the sampled soils ranged from below the method detection limit to 23.7 ng/g (mean of 4.72 ± 4.07 ng/g), with androgens and progestins being the most dominant hormone groups. Significant correlations were observed among the concentrations of Σestrogens, Σandrogens, and Σprogestins (r = 0.117-0.433, p < 0.001), suggesting similar sources of sex hormones. The mean concentration of Σsex hormones varied considerably across the selected provinces/municipality. Notably, the annual slaughter of poultry and swine (R2 = 0.75-0.88), female population (R2 = 0.57-0.58), and soil organic carbon content (R2 = 0.20-0.55) in each province were significantly correlated with the concentrations or mean concentrations of Σsex hormones, Σestrogens, or Σprogestins. This finding implies that these parameters contributed to the occurrence and distribution of sex hormones in the studied soils. Finally, risk quotients for some sex hormones exceeded 0.01, indicating medium or high risks to agroecosystems. This study highlights the importance of designing an optimal manure fertilization strategy in order to mitigate the risks posed by sex hormones in agroecosystems.

Effects of hyaluronic acid on differentiation of human amniotic epithelial cells and cell-replacement therapy in type 1 diabetic mice.

Our hypothesis is that hyaluronic acid may regulate the differentiation of human amniotic epithelial cells (hAECs) into insulin-producing cells and help the treatment of type 1 diabetes. Herein, a protocol for the stepwise in vitro differentiation of hAECs into functional insulin-producing cells was developed by mimicking the process of pancreas development. Treatment of hAECs with hyaluronic acid enhanced their differentiation of definitive endoderm and pancreatic progenitors. Endodermal markers Sox17 and Foxa2 and pancreatic progenitor markers Pax6, Nkx6.1, and Ngn3 were upregulated an enhanced gene expression in hAECs, but hAECs did not express the ß cell-specific transcription factor Pdx1. Interestingly, hyaluronic acid promoted the expression of major pancreatic development-related genes and proteins after combining with commonly used inducers of stem cells differentiation into insulin-producing cells. This indicated the potent synergistic effects of the combination on hAECs differentiation in vitro. By establishing a multiple injection transplantation strategy via tail vein injections, hAECs transplantation significantly reduced hyperglycemia symptoms, increased the plasma insulin content, and partially repaired the islet structure in type 1 diabetic mice. In particular, the combination of hAECs with hyaluronic acid exhibited a remarkable therapeutic effect compared to both the insulin group and the hAECs alone group. The hAECs' paracrine action and hyaluronic acid co-regulated the local immune response, improved the inflammatory microenvironment in the damaged pancreas of type 1 diabetic mice, and promoted the trans-differentiation of pancreatic α cells into ß cells. These findings suggest that hyaluronic acid is an efficient co-inducer of the differentiation of hAECs into functional insulin-producing cells, and hAECs treatment with hyaluronic acid may be a promising cell-replacement therapeutic approach for the treatment of type 1 diabetes.

Hyaluronic acid promotes osteogenic differentiation of human amniotic mesenchymal stem cells via the TGF-ß/Smad signalling pathway.

AIMS: This study investigated the effects of hyaluronic acid (HA), a commonly used osteogenic medium referred to as DAG, and the combined administration of HA and DAG (CG) on the osteogenic differentiation of human amniotic mesenchymal stem cells (hAMSCs), and the underlying mechanism. MAIN METHODS: The phenotype of hAMSCs was detected by flow cytometry and immunocytochemical staining. Alkaline phosphatase (ALP) and calcium deposition assays were employed for evaluating the osteogenic differentiation of hAMSCs. The expression of osteogenesis-related genes and proteins was determined by quantitative reverse transcription PCR (qRT-PCR) and Western blotting, respectively. Meanwhile, the molecular mechanism of osteogenic differentiation of hAMSCs was detected by PCR array and qRT-PCR. KEY FINDINGS: The results showed that treatment with CG could significantly stimulate hAMSC ALP activity and calcium deposition compared to treatment with DAG, while HA had little effect. The expression of osteogenesis-related molecules and stemness-related molecules was up-regulated at the mRNA and protein levels in all three groups, and this up-regulation was most significant in the CG group. In addition, treatment with CG significantly increased the gene expressions involved in regulation of the TGF-ß/Smad signalling pathway compared to treatment with DAG. Furthermore, the pro-osteogenic differentiation effects as well as the up-regulated expression of genes observed in the CG treatment group were significantly inhibited when the cells were pre-treated with SB431542, an inhibitor of the TGF-ß/Smad pathway. SIGNIFICANCE: These results suggest that HA in combination with DAG could significantly enhance the osteogenic differentiation of hAMSCs, potentially via the TGF-ß/Smad signalling pathway.

Synergistic antitumor efficacy of antibacterial helvolic acid from Cordyceps taii and cyclophosphamide in a tumor mouse model.

The antibacterial agent helvolic acid, which was isolated from the active antitumor fraction of Cordyceps taii, showed potent cytotoxicity against different human cancer cells. In the present study, the in vivo antitumor effect of helvolic acid was investigated in murine sarcoma S180 tumor-bearing mice. Doses of 10 and 20 mg/kg/day helvolic acid did not exert significant antitumor activity. Interestingly, co-administration of 10 mg/kg/day helvolic acid and 20 mg/kg/day cyclophosphamide (CTX) - a well-known chemotherapy drug - showed promising antitumor activity with a growth inhibitory rate of 70.90%, which was much higher than that of CTX alone (19.5%). Furthermore, the combination markedly prolonged the survival of tumor-bearing mice. In addition, helvolic acid enhanced the immune organ index. The protein expression levels of ß-catenin, cyclin D1, and proliferating cell nuclear antigen were significantly suppressed in mice treated with 20 mg/kg/day helvolic acid and in those receiving combination therapy. Taken together, these results indicated that helvolic acid in combination with CTX showed potent in vivo synergistic antitumor efficacy, and its mechanism of action may involve the Wnt/ ß-catenin signaling pathway.

Hyaluronic acid enhances proliferation of human amniotic mesenchymal stem cells through activation of Wnt/ß-catenin signaling pathway.

This study investigated the pro-proliferative effect of hyaluronic acid (HA) on human amniotic mesenchymal stem cells (hAMSCs) and the underlying mechanisms. Treatment with HA increased cell population growth in a dose- and time-dependent manner. Analyses by flow cytometry and immunocytochemistry revealed that HA did not change the cytophenotypes of hAMSCs. Additionally, the osteogenic, chondrogenic, and adipogenic differentiation capabilities of these hAMSCs were retained after HA treatment. Moreover, HA increased the mRNA expressions of wnt1, wnt3a, wnt8a, cyclin D1, Ki-67, and ß-catenin as well as the protein level of ß-catenin and cyclin D1 in hAMSCs; and the nuclear localization of ß-catenin was also enhanced. Furthermore, the pro-proliferative effect of HA and up-regulated expression of Wnt/ß-catenin pathway-associated proteins - wnt3a, ß-catenin and cyclin D1 in hAMSCs were significantly inhibited upon pre-treatment with Wnt-C59, an inhibitor of the Wnt/ß-catenin pathway. These results suggest that HA may positively regulate hAMSCs proliferation through regulation of the Wnt/ß-catenin signaling pathway.

Expression and regulation of interleukin-9 in chronic rhinosinusitis.

BACKGROUND: The pathogenesis of human chronic rhinosinusitis (CRS) remains controversial. Recent evidence has suggested that interleukin (IL)-9 is vital in eliciting inflammatory response, stimulating cell proliferation and preventing apoptosis, through binding to the IL-9 receptor (IL-9R). However, little is known about the roles of both molecules in the etiology of CRS. Therefore, this study aimed to assess IL-9 and IL-9R expression and determine their roles in the pathophysiology of CRS. METHODS: Immunohistochemistry was used to assess IL-9 and IL-9R immunolabeling. In addition, Western blotting and real-time polymerase chain reaction (PCR) were used for IL-9 and IL-9R protein and mRNA level quantitation, respectively, in CRS and control subjects. Furthermore, the effects of various stimulators at different concentrations and time on IL-9 were evaluated using nasal explant cultures. RESULTS: IL-9 and IL-9R were overexpressed in CRS, especially in CRS with nasal polyps. Interestingly, IL-9 expression was closely related to that of IL-9R. In addition, IL-9 mRNA levels were increased by treatment with IL-4, IL-17A, IL-1beta, and the IL-4 and transforming growth factor (TGF) beta1 combination, but suppressed by interferon gamma and IL-27. CONCLUSION: IL-9 and IL-9R were overexpressed in CRS at both protein and mRNA levels. In addition, IL-4, IL-17A, IL-1beta, and the IL-4 and TGF-beta1 combination contributed to increased IL-9 levels. Our findings indicate that IL-9 may play a proinflammatory role after IL-9R binding to induce mucosal epithelial cell growth, gland epithelial cell proliferation, and inflammatory cell infiltration in CRS. Future studies are required to further define the role of IL-9 in CRS etiology.

Downregulation of caveolin-1 in chronic rhinosinusitis with and without nasal polyps.

The pathogenesis of human chronic rhinosinusitis (CRS) remains controversial. Recent evidence has suggested that caveolin-1 (Cav-1) is a 22 kDa scaffolding protein and plays a pivotal role in host defense against infections and tumour suppression by reducing production of cyclin D1 and endothelial nitric oxide-synthase (eNOS). However, little is known about their roles in CRS. Therefore, we aimed to investigate the expression and role of Cav-1 in CRS. Cav-1 protein expression were investigated by immunohistochemistry method and mRNA expression of Cav-1, cyclin D1 and eNOS were assessed by real-time polymerase chain reaction in CRS and control subjects. Moreover, the effects of various stimulators with different concentrations and time on Cav-1 were evaluated on nasal explant culture. The results showed that weaker expression of Cav-1 protein and mRNA were observed in CRS, especially in CRS with nasal polyps (CRSwNP), stronger mRNA expression of cyclin D1 and eNOS were observed in CRS and Cav-1 expression was negatively related to cyclin D1 and eNOS expression, respectively. Cav-1 mRNA was augmented by IFN-γ, but supressed by IL-4 and IL-1ß. In conclusion, the expression of Cav-1 was downregulated in CRS and the role of Cav-1 was impaired in CRS, especially in CRSwNP, leading to the attenuation of inhibition effect on cyclin D1 and eNOS and resulted in the overexpression of cyclin D1 and eNOS. IFN-γ may be essential for Cav-1 gene expression.

Role of platelet-derived growth factor-α in eosinophilic and non-eosinophilic chronic rhinosinusitis with nasal polyps.

BACKGROUND: The pathogenesis of human chronic rhinosinusitis with nasal polyps (CRSwNP) comprising eosinophilic CRSwNP (ECRSwNP) and non-eosinophilic (nECRSwNP) is not completely understood. Recent evidence has suggested that platelet-derived growth factor receptor alpha (PDGFRα) is implicated in cell growth, transformation, proliferation, migration, and vascular permeability and platelet-derived growth factor-A (PDGF-A) is a specific ligand for PDGFRα. However, little is known about their roles in CRSwNP. Therefore, we aimed to investigate the expression and role of PDGFRα and PDGF-A in CRSwNP. METHODS: PDGFRα protein expression was investigated by immunohistochemistry method and messenger RNA (mRNA) expression of PDGFRα and PDGF-A were assessed by real-time polymerase chain reaction (PCR) in CRSwNP patients and control subjects. Moreover, the effects of various stimulators with different concentrations and time on PDGFRα were evaluated on nasal explant culture. RESULTS: Quantitative analysis of immunostaining for PDGFRα showed an obvious elevation in immunolabeling of PDGFRα in CRSwNP groups compared with controls. Furthermore, PDGFRα protein was significantly stronger expressed in ECRSwNP group than nECRSwNP group and atopic patients showed stronger expression of PDGFRα protein than nonatopic patients. The mRNA of PDGFRα and PDGF-A were overexpressed in CRSwNP, especially in ECRSwNP. PDGFRα mRNA expression was closely related to PDGF-A mRNA. In nasal explant culture and stimulation, PDGFRα mRNA was augmented by interleukin 4 (IL-4), IL-5, or IL-1ß respectively, but suppressed by IL-27. CONCLUSION: PDGFRα may play a pivotal role in the pathophysiology of ECRSwNP and nECRSwNP by combining with PDGF-A. IL-4, IL-5, or IL-1ß may be critical for PDGFRα gene expression.

Jiangxienone, a new compound with potent cytotoxicity against tumor cells from traditional Chinese medicinal mushroom Cordyceps jiangxiensis.

A new compound, named jiangxienone, has been isolated from a culture of the traditional Chinese medicinal mushroom Cordyceps jiangxiensis, and its chemical structure was established on the basis of spectroscopic and chemical techniques. Jiangxienone showed potent cytotoxic effects against human gastric adenocarcinoma SGC-7901 cell and human lung carcinoma A549 cell with IC(50) values ranging from 1.38 to 2.93 µM, i.e., with at least approximately six-fold stronger cytotoxicity than cisplatin, a first-line chemotherapy drug for cancer patients.

[Study on inducing differentiation of human amniotic epithelial cells into insulin secreting cells in vitro].

OBJECTIVE: To investigate the differentiation of human amniotic epithelial cells (hAECs) into insulin secreting cells (ISCs) in vitro. METHODS: The hAECs were isolated from human amnion by trypsin digestion, and the phenotype of the isolated cells were identified by flow cytometry and immunocytochemical staining. The hAECs at passage 3 were treated with nicotinamide and N2 supplement to investigate their differentiation into ISCs. At different times after differentiation, the expression of insulin and beta2 microglobulin (beta2-MG) was determined by immunocytochemical staining, while the content of insulin in supernatant from cultured hAECs was detected by radioimmunoassay and the expressions of insulin, pancreatic and duodenal homeobox factor-1 (PDX-1) mRNA were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: (1) hAECs expressed high percent of CD29, CD73, CD166 and CK19. (2) At 7, 14 and 21 days, the percentages of insulin-positive cells in induced groups were 74.00% +/- 1.73%, 75.33% +/- 1.15% (see symbol) 75.67% +/- 0.58% respectively, which were negative in control groups. (3) At 7, 14 and 21 days, contents of insulin in supernatant from induced groups were (328.47 +/- 3.22) microIU/ml, (332.26 +/- 1.22) microIU/ml and (329.68 +/- 2.57) microIU/ml respectively, they were significantly higher than those in control groups (All P < 0.01). (4) PDX-1 mRNA and beta2-MG were expressed before and after the induction of hAECs, but insulin mRNA was expressed only in the induced groups. CONCLUSION: hAECs can differentiate into ISCs, having the potential application for therapy of type I diabetes.

Establishment of a cell-based drug screening model for identifying agonists of human peroxisome proliferator-activated receptor gamma (PPARγ).

OBJECTIVES: Peroxisome proliferator-activated receptor gamma (PPARγ) plays a critical role in regulation of diverse biological processes, including lipid metabolism and adipogenesis, cell division and apoptosis, and is involved in variety of disease conditions, such as obesity, atherosclerosis, inflammation and tumour. Developing a cell-based reporter gene model targeting PPARγ would be useful to screen human PPARγ agonists that could be beneficial to patients with these diseases. METHODS: We stably co-transfected human embryonic kidney (HEK) cell line 293T cells with phPPARγ-IRES2-EGFP vector to express human PPARγ (hPPARγ), a reporter vector pPPRE×3-TK-LUC, and control vector pRL-CMV. The efficiency of the co-transfection was evaluated with flow cytometry of hPPARγ expressing cells. Specificity of hPPARγ activity was determined by dual luciferase reporter assay of co-transfected cells exposed to PPARγ agonist rosiglitazone, PPARα agonist WY14643 and retinoic acid receptor alpha (RARα) agonist all-trans-retinoic acid (ATRA). KEY FINDINGS: The phPPARγ-IRES2-EGFP co-transfected HEK293T cells showed concentration- and time-dependent luciferase induction upon exposure to the rosiglitazone, while WY14643 and ATRA were unable to activate the co-transfected HEK293T cells. CONCLUSIONS: These data indicated that the HEK293T cells could be stably transfected with hPPARγ. This cell-based drug screening platform could be used targeting specific nuclear receptor of hPPARγ with effectiveness and specificity for hPPARγ agonists discovery.

[CD133(+) cells derived from human placenta identified as initiating cells for LTC-IC colony formation].

The aim of this study was to evaluate whether human placenta CD133(+) cells have an ability to reconstitute long-term hematopoiesis. Magnetic-activated cell sorting (MACS) was applied to enrich human placental CD133(+) cells. The isolated human placental CD133(+)cells of four different densities were established by limiting-dilution assay and primary fetal bone marrow stromal cells separated from bone marrow as feeder layer cells were co-cultured in long-term culture system so as to observe the incidence of long-term culture initiating-cells (LTC-IC) and their ability of proliferation and differentiation.The results showed that human placenta derived CD133(+) cells contained LTC-IC with frequency of 1/645 which have an ability to proliferate and differentiate into granulocyte/macrophage colony-forming units (CFU-GM) and mixed colony-forming units (CFU-Mix). In all LTC-IC positive wells, 71.43% form only CFU-GM and 28.57% display both CFU-GM and CFU-Mix formation. It is concluded that human placental CD133(+) cells possess LTC-IC with colony-forming capacity of hematopoietic early progenitor cells.

[Investigation on antitumor mechanism of polysaccharide from medicinal fungus Penicillium jiangxiense].

OBJECTIVE: To investigate the possible antitumor mechanism of polysaccharide from medicinal fungus Penicillium jiangxiense. METHODS: The cytotoxic effect was measured by MTT assay, and the cell cycle was analyzed by flow cytometry with Propidium iodide (PI) staining. To apoptotic detections, Hoechst 33258 staining for chromatin, annexin-V FITC/PI double staining for early phase cell apoptosis and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) for late phase cell apoptosis. RESULTS: Both MPPJ4 and MPPJ5, the fine polysaccharide fractions from P. jiangxiense, showed slight cytotoxic effects to inhibit human gastric adenocarcinoma SGC-7901 cells proliferation, but significantly caused cell cycle arrest at the S phase, and the rate of cell population at the subG1 phase was evidently increased. In apoptotic assays, MPPJ5 was more potent than MMPJ4 in inducing tumor cells in a time-dependent manner at the range from 0 to 72 hours, comparable to the negative control. CONCLUSION: The antitumor acting mechanism of P. jiangxiense polysaccharide is associated with the induction of apoptotic cell death and cell cycle arrest.

[Ex vivo expansion of megakaryocyte progenitor cells for CD133(+) cells derived from human umbilical cord blood].

To study the expansion potentiality of megakaryocyte progenitor cells (MPCs) derived from human umbilical cord blood CD133(+) (UCB-CD133(+)) cells and determine the optimal harvest time. UCB-CD133(+) cells were purified from mononuclear cells (MNCs) by magnetic activated cell sorting (MACS) and seeded in serum-free liquid culture medium supplemented with thrombopoietin (TPO), interleukin-3 (IL-3), and stem cell factor (SCF) to expand MPCs. At day 0, 6, 10 and 14 of culture, the total cell number was counted and the dynamic changes of CD133, CD34, and CD41 antigen expression during ex vivo expansion were analyzed by flow cytometry (FCM). At different expansion times, the CD133(+) cells were collected and cultured in collagen semisolid medium to carry out CFU-MK colony culture. The incidence of CFU-MK was calculated and the morphology of MPCs and CFU-MK were detected by immunohistochemistry and Wright-Giemsa staining. The results showed that UCB-CD133(+) cells optimally expanded at day 7 with expansion multiple of 8.2 +/- 2.2 in serum-free liquid culture systems and the total cell number was expanded by 116-fold at day 14. At 10 days, each UCB-CD133(+) cell can form 2.5 +/- 1.0, 2.6 +/- 0.5 and 20.3 +/- 5.9 cells of CD133(+)CD41(+), CD34(+)CD41(+) and CD41(+) respectively, from which the number of CD133(+)CD41(+) and CD34(+)CD41(+) cells reach the highest. UCB-CD133(+) cells both before and after expansion could form CFU-MK, the total number of CFU-MK reached the peak from cells of 10 days expansion of UCB-CD133(+) cells and the expansion multiple of CFU-MK was 59.5 +/- 11.8. Immunohistochemical results indicated that the expanded megakaryocytic cells were immature and no sign of platelet formation. It is concluded that the human UCB-CD133(+) cells have a high ability of MPC expansion, 10 days of culture can be result in optimal expansion effect.

[In vitro expansion of megakaryocyte progenitor cells from human placenta CD133+ cells].

OBJECTIVE: To study the expansion potential of megakaryocyte progenitor cells (MPC) from human placenta tissue CD133+ (PT-CD133+) cells. METHODS: PT-CD133+ cells were purified from mononuclear cells (MNC) by magnetic activated cell sorting (MACS) and seeded in serum-free liquid culture medium supplemented with thrombopoietin (TPO), interleukin-3 (IL-3), and stem cell factor (SCF) to expand MPC. At day 7, 10 and 14, the total cell number was counted and the dynamic changes of CD133, CD34, and CD41 antigens expression during ex-vivo expansion were analyzed by flow cytometry (FCM). PT-CD133+ cells at different expansion time were collected and cultured in collagen semisolid medium for colony forming units-megakaryocyte (CFU-MK) assay. RESULTS: PT-CD133+ cells could be optimally expanded at day 7 by 13 +/- 2 fold increase in serum-free liquid culture systems and the total cell number was expanded by 160 fold at day 14. With the expansion time going on, the expression of CD133, CD34 decreased and that of CD41 increased. The expanded megakaryocytes were immature and no sign of platelet formation. Both PT-CD133+ cells before and after expansion could form CFU-MK, the total number of CFU-MK peaked at day 10 of expansion by 54 +/- 10 fold increase. CONCLUSION: Human PT-CD133+ cells have a high capacity of MPC expansion, 10 days culture could give rise to the maximum number of CFU-MK.

[Isolation and enrichment of hematopoietic stem/progenitor cells from human placenta tissue].

The aim of this study was to establish the standard protocols for isolating and enriching hematopoietic stem/progenitor cells (HSPC) from human placenta tissue (PT). Single-cell suspension from of human PT was prepared by mechanical method combined with collagenase digestion. Mononucleated cells (MNC) derived from PT were separated by hydroxyethyl starch (6% HES), then the three cell subsets of different immunophenotypes (CD34(-), CD34(+)CD38(-), CD34(+)CD38(+)) contained in MNC were isolated by Magnetic Activated Cell Sorting (MACS). The cell immunophenotype of each sorting steps was analyzed by flow cytometer (FCM). The cell enrichment and recovery rate of each sorting step were calculated. The results showed that MNC could be harvested up to (12.30 +/- 3.51) x 10(8) from a single-cell suspension of human PT by mechanical method and collagenase digestion, no significant difference existed as compared with umbilical cord blood (UCB) initial sample [(8.86 +/- 5.38) x 10(8)], but the percentage of CD34(+) cells in MNC of human PT was (3.93 +/- 2.31)%, much higher than that in UCB [(0.44 +/- 0.29)%] (P < 0.001). recovery rate of MNC and CD34(+) cells from PT after separation with 6% HES were (45.3 +/- 11.7)% and (51.1 +/- 9.8)%, respectively. After MNC being sorted by MACS, the enrichment and recovery rate of CD34(+) cells in CD34(+) group were (73.4 +/- 14.1)% and (52.7 +/- 11.7)% respectively. It is concluded that the protocols established here for isolating and enriching hematopoietic stem/progenitor cells from human placenta can acquire HSPC with high abundance, enrichment and viability and may be a useful reference of isolating methods for future related study.

Effects of histamine on immunophenotype and notch signaling in human HL-60 leukemia cells.

Surface molecules are important biomarkers for cell proliferation and differentiation and play important roles in cell function and cell interaction. Notch is a transmembrane receptor that regulates developmental processes and cell-fate decision. Histamine is used as an adjunct to immunotherapy in myelogenous leukemia, and regulates hematopoietic cell development. Thus, we investigated the effects of histamine on immunophenotype and Notch signaling in human HL-60 leukemia cells. Histamine (0.1-10 microM) inhibited the colony-forming efficiency of HL-60 cells in a dose-dependent fashion and shifted the growth curve to the right. HL-60 cells were treated with histamine 0.1-1.0 microM for 6 days, and surface molecules were analyzed by flow cytometry. Histamine decreased CD49d positive cells by 74% while increasing CD31 positive cells by 53% as compared to controls. Histamine did not affect the expression of CD11b, CD14, CD34, CD44, CD54, CD49e, and CD62L. To examine Notch signaling in histamine-induced immunophenotype alterations in HL-60 cells, total RNA was isolated, purified, and subjected to real-time RT-PCR analysis. The expressions of Notch1, Notch4, the ligands Jagged1, Delta4, and the downstream hairy enhancer of split 1 gene (HES1) were not significantly altered by histamine. In summary, this study demonstrated that histamine inhibited HL-60 cell growth and regulated immunophenotypes of CD49d and CD31. These effects are not mediated through the Notch signaling.

[Expressions of homing-related adhesion molecules in hematopoietic stem/progenitor cells derived from human placenta, umbilical cord arterial and venous blood].

The aim of this study was to evaluate the homing capabilities of hematopoietic stem/progenitor cells (HSPCs) derived from human placenta tissues (PT). Single cell suspension of human PT was prepared by mechanical method. The expression levels of homing-related adhesion molecules (HRAM) including CD11a, CD49d, CD44, CD49e, CD62L and CD54 on CD34(+) cells and the percentages of CD34(+) cells and their subpopulations in nucleated cells (NC) from fresh human PT, umbilical cord arterial blood (UCAB) and umbilical cord venous blood (UCVB) were detected by using flow cytometry. The results showed that the percentage of CD34(+) cells and CD34(+)CD38(-) cells in placenta were higher than those in UCAB and UCVB. There were no significant difference in percentage of HSPC between UCAB and UCVB. Placenta-derived CD34(+) cells strongly expressed CD11a, CD49d, CD44, CD49e and CD54, among which expression levels of CD49e and CD54 on placenta-derived CD34(+) cells were significantly higher than those on UCAB and UCVB-derived CD34(+) cells. While the percentage of CD34(+)CD62L(+) cells in placenta was only lower than that in UCVB. It is concluded that human placenta is rich in HSPC. Moreover, the expression levels of most HRAM in CD34(+) cells from PT are higher than those from UCAB and UCVB or are close to them. It suggested that HSPCs derived from PT might have stronger homing capabilities than those from UCB.

[Hematopoietic stem/progenitor cells and phenotypes of lymphocyte subpopulations in human placenta].

OBJECTIVE: To study whether human placenta contains hematopoietic stem/progenitor cells (HSPCs), and analyze phenotypes of lymphocyte subpopulations in the placenta. METHODS: Nucleated cells from fresh human placenta were analyzed for phenotypes of HSPCs and lymphocyte subpopulations by flow cytometry (FCM). And CD(34)(+) cells were sorted from human placenta nucleated cells by FCM or MiniMACS. RESULTS: (1) CD(34)(+) cells, CD(34)(+)/CD(38)(+) cells, and CD(34)(+)/CD(38)(-) cells from a human placenta were 8.8, 4.6 and 11.9 times higher than those from umbilical cord blood (UCB), respectively. (2) The yields and purity of CD(34)(+) cells isolated from human placenta by FCM sorting system were (63.05 +/- 10.14)% and (86.39 +/- 11.27)%, respectively. (3) Lymphocytes, T cells (CD(3)(+)/CD(2)(+)), B cells (CD(19)(+)), Th cells (CD(3)(+), CD(4)(+)), and Th/Ts ratio in the placenta tissue were apparently lower than those in the UCB, while the CD(8)(+)/CD(28)(-) T suppressor cells were higher in the placenta than in the UCB. CONCLUSIONS: Human placenta is rich in HSPCs, and has important hematopoietic function in ontogeny. It is probable that human placenta would be graft resource for HSPCs transplantation. CD(8)(+)/CD(28)(-) T suppressor cells might play an important role in feto-maternal immunologic tolerance.