OBJECTIVETo Explore a two-step culture system to generate a large number of dendritic cells (DC) differentiated from cord blood (CB) CD(34)(+) cells.

METHODSEnriched CB CD(34)(+) cells with immunoadsorption were primarily cultured in the presence of stem cell factor (SCF), Flt-3 ligand (FL), thrombopoietin (Tpo) and interleukin-3 (IL-3) for 7 (group I), 10 (group II) or 14 days (group III) respectively, and then further cultured with GM-CSF, IL-4 and TNF-alpha for 5 - 8 days to induce DC. The expansion and cell function were evaluated by flow cytometry (FCM) and mix-lymphocyte reaction (MLR), and detection of IL-12 in the supernatant by using ELISA.

RESULTSThe total nucleated cells with 53.39 +/- 20.59-, 307.17 +/- 119.59- and 1117.25 +/- 335.49-folds expansion could be respectively obtained after 7 - 14 days of expansion culture. After DC induction, CD(1a)(+) cells were 21.40 +/- 16.70-, 143.2 +/- 60.35- and 150.8 +/- 42.16-fold increase as compared to the initial nucleated cells. Comparing with that in group I, the CD(1a)(+) cells were much more in groups II and III; but there was no difference between the latter two groups (P > 0.05). The cultured cells in the three groups showed almost the same allo-stimulatory capability and IL-12 excretion when the second culture duration maintained 8 days, while the capability and excretion were greatly decreased when the duration shortened to 5 days (P < 0.05).

CONCLUSIONA plenty of functionally mature DC could be obtained from the CD(34)(+) cells in the two-step culture system of 7 - 10 days HSC expansion followed by 8 days DC induction.

Antigens, CD34 ; analysis ; Cell Differentiation ; Cells, Cultured ; Dendritic Cells ; cytology ; physiology ; Fetal Blood ; cytology ; Hematopoietic Stem Cells ; cytology ; Humans ; Interleukin-12 ; biosynthesis ; Lymphocyte Activation

OBJECTIVETo study the changes of IL-12 produced by dendritic cells in peripheral blood in children with Henoch-Schonlein purpura (HSP), and to explore its influence on TH1/TH2 balance in order to elucidate its significance in the pathogenesis of HSP.

METHODSThe levels of interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and interleukin-12 (IL-12) in plasma were determined by ELISA in 60 HSP children (HSP group) and 21 healthy children (Control group). Peripheral blood mononuclear cells (PBMC) of 22 HSP patients and 21 healthy children were cultured in vitro and then were transformed into dendritic cells. The levels of IL-12 in the supernatant were detected by ELISA and the positive expression rate of CD1a(+) was detected by indirect immunofluorescence procedure.

RESULTS1) The levels of IFN-gamma and the ratio of IFN-gamma/IL-4 in plasma of the HSP group were lower than those of the Control group (IFN-gamma 30.59 +/- 11.27 pg/mL vs 43.38 +/- 19.19 pg/mL; IFN-gamma/IL-4 ratio 0.70 +/- 0.28 vs 1.33 +/- 0.57) (P < 0.01). The levels of IL-12 in the HSP group were also lower than those of the Control group (153.95 +/- 91.88 pg/mL vs 323.06 +/- 162.34 pg/mL; P < 0.01). In contrast, the levels of IL-4 were higher than those of the Control group (45.08 +/- 9.19 pg/mL vs 32.95 +/- 7.10 pg/mL; P < 0.01). The plasma levels of IL-12 positively correlated with the IFN-gamma levels (r=0.52, P < 0.01) and the ratio of IFN-gamma/IL-4 (r=0.43, P < 0.01) in the HSP group. 2) The IL-12 levels in the supernatant of the HSP group were lower than those of the Control group (357.06 +/- 153.56 pg/mL vs 489.80 +/- 213.45 pg/mL; P < 0.05), and had a positive correlation with the plasma IL-12 levels (r=0.74, P < 0.01). 3) The positive expression rate of CD1a(+) of the HSP group was lower than that of the Control group [(27.42 +/- 10.75)% vs (35.68 +/- 12.18)%; P < 0.05], and positively correlated with the IL-12 levels in the supernatants (r=0.57, P < 0.01) and in plasma (r=0.68, P < 0.01).

CONCLUSIONSThere was an imbalance of TH1/TH2 in HSP children. The decrease of TH1 function had a positive correlation with the low levels of IL-12 in plasma, while the latter correlated closely with decreased number and / or function of dendritic cells, suggesting that the decreased number and / or function of dendritic cells in peripheral blood resulted in the imbalance of TH1/TH2 indirectly.

Adolescent ; Antigens, CD1 ; analysis ; Cells, Cultured ; Child ; Child, Preschool ; Dendritic Cells ; immunology ; Female ; Humans ; Interferon-gamma ; blood ; Interleukin-12 ; biosynthesis ; blood ; Interleukin-4 ; blood ; Male ; Purpura, Schoenlein-Henoch ; immunology ; Th1 Cells ; immunology ; Th2 Cells ; immunology

For treating Leishmania major infection in BALB/c mice, we used thalidomide in conjunction with glucantime. Groups of mice were challenged with 5 x 10(3) metacyclic promastigotes of L. major subcutaneously. A week after the challenge, drug treatment was started and continued for 12 days. Thalidomide was orally administrated 30 mg/kg/day and glucantime was administrated intraperitoneally (200 mg/kg/day). It was shown that the combined therapy is more effective than single therapies with each one of the drugs since the foot pad swelling in the group of mice received thalidomide and glucantime was significantly decreased (0.9 +/- 0.2 mm) compared to mice treated with either glucantime, thalidomide, or carrier alone (1.2 +/- 0.25, 1.4 +/- 0.3, and 1.7 +/- 0.27 mm, respectively). Cytokine study showed that the effect of thalidomide was not dependent on IL-12; however, it up-regulated IFN-gamma and down-regulated IL-10 production. Conclusively, thalidomide seems promising as a conjunctive therapy with antimony in murine model of visceral leishmaniasis.
Time Factors ; Thalidomide/pharmacology/*therapeutic use ; Organometallic Compounds/pharmacology/*therapeutic use ; Mice, Inbred BALB C ; Mice ; Meglumine/pharmacology/*therapeutic use ; Leishmaniasis, Visceral/*drug therapy/immunology ; Leishmania major/*drug effects ; Interleukin-12/analysis/biosynthesis ; Interleukin-10/analysis/biosynthesis ; Interferon Type II/analysis/biosynthesis/drug effects ; Immunosuppressive Agents/pharmacology/*therapeutic use ; Female ; Drug Therapy, Combination ; Disease Progression ; Disease Models, Animal ; Cells, Cultured ; Antiprotozoal Agents/pharmacology/*therapeutic use ; Animals

Several myeloid leukemia-derived cells have been reported to possess the ability to differentiate into dendritic cells (DC). MUTZ-3, a myeloid leukemia cell line, responds to GM-CSF, IL-4 and TNF-alpha, and acquires a phenotype similar to immature monocyte-derived DC (MoDC). In the present study, MUTZ-3-derived DC (MuDC) showed high level expression of HLA class II molecules, CD80 and CD86, and were able to function as potent antigen presenting cells as previously reported. Interestingly, MuDC maturation was induced by CD40-mediated stimulation, but not by LPS stimulation. We analyzed CCR1, CCR7 and Toll-like receptor (TLR) expressions in MuDC, and measured IL-10 and IL-12 production after maturation stimuli. Although MuDC expressed the mRNA for TLR4, a major component of the LPS receptor system, they did not show an enhanced level of CCR7 or cytokine production after LPS stimulation. In contrast, they responded to CD40 stimulation, which resulted in increased levels of CD83, CD86 and CCR7. Moreover, while LPSstimulated MoDC could potently stimulate NK cells in a DC-NK cell co-culture, LPS-stimulated MuDC failed to stimulate primary NK cells. Taken together, our findings suggest that, although MuDC express TLR4, unlike TNF-alpha and IL-1beta, LPS does not stimulate MuDC to acquire mature phenotypes, and they may have impaired activity to initiate innate immune response.
Antigens, CD40/metabolism/pharmacology ; Antigens, CD80/metabolism ; Antigens, CD86/metabolism ; Blotting, Western ; CD40 Ligand/metabolism/pharmacology ; Cell Differentiation ; Cell Line, Tumor ; Coculture Techniques ; Dendritic Cells/*drug effects/metabolism ; Enzyme-Linked Immunosorbent Assay ; Fluorescein-5-isothiocyanate ; Fluorescent Antibody Technique, Indirect ; Fluorescent Dyes ; Humans ; Interleukin-10/analysis/biosynthesis ; Interleukin-12/analysis/biosynthesis ; Killer Cells, Natural/metabolism ; Leukemia, Myeloid/*pathology ; Lipopolysaccharides/*pharmacology ; Mitogen-Activated Protein Kinase 3/metabolism ; RNA, Messenger/metabolism ; Research Support, Non-U.S. Gov't ; Reverse Transcriptase Polymerase Chain Reaction ; Toll-Like Receptor 4/metabolism ; Tumor Necrosis Factor-alpha/pharmacology ; p38 Mitogen-Activated Protein Kinases/metabolism