RESUMEN
Objective To investigate the mechanism of hypoxia regulate osteopontin (OPN) secreting by mature dendritic cells (mDCs). Methods CD14 + cells were enriched using anti-CD14 immunomagnetic beads, for inducing to mDCs, CD14 + cells were cultured with GM-CSF and IL-4 in hypoxia or normoxiain vitro. Concentration of OPN and TGF-β1 in supernatant were detected by sandwich ELISA, OPN mRNA detected by RT-PCR. Approach regulating function of A2 R in expressing of OPN by mDCs by using NECA (surrogate of adenosine), A2R agonist (CGS21680), A2R antagonist (SCH58261) and investigate role of TGF-β1 in this process by using rhTGF-β1 and anti-TGF-β1 Ab. Results Hypoxia inreased the level of OPN and OPN mRNA in mDCs, and this effect could be reversed by A2 R antagonist. Under normoxia,both NECA and A2R agonist (CGS21680) could upregulate the level of OPN and OPN mRNA in mDCs significantly, but this positive effect could be reversed by A2 R antagonist. A2 R played a role in regulating TGF-β1, and confirmed TGF-β1 involved in regulation of OPN by using rhTGF-β1 and anti-TGF-β1 Ab. Conclusion High adenosine induce the generation of TGF-β1 through the A2R on mDCs, and then TGF-β1 raise the OPN secreting by mDCs.
RESUMEN
PURPOSE: Dendritic cells (DCs) are the most potent antigen presenting cells and should be differentiated to mature form to induce primary T cell response. In this study, we intended to generate mature DCs from peripheral blood mononuclear cells (PBMCs), so that develope the basis for immunotherapy using DCs. METHODS: PBMCs were isolated from 25 mL of normal adults' peripheral blood and evenly distributed in 5 wells of a 6-well plate. Nonadherent cells were gently aspirated after 2 hour-incubation under humidified 5% CO2 at 37degrees C. Adherent monocytes were cultured in 3 mL of 10% fetal bovine serum plus RPMI-1640 media containing granulocyte/macrophage-colony stimulating factor (GM-CSF) 200 ng/mL and interleukin (IL)-4 20 ng/mL. To assess the effect of tumor necrosis factor (TNF)-alpha and interferon (IFN)-alpha on DC maturation, either or both were added on day 4 of culture. Cells were harvested on day 4 and 7 to calculate the cell counts, CD83 /HLA-DR cells, and CD86 /HLA-DR cells. RESULTS: On day 4, large amounts of DCs were observed. CD83 /HLA-DR cells and CD86 / HLA-DR cells were 11.6% and 16.6% of total cells counted and yields were 1.3% and 2.0%, respectively. On day 7, DCs were more frequently observed in all instances and purity ranged from 24.0% to 31.0% as a mean value. The final yields of matue DCs were 2.9~3.4% of PBMCs inoculated. Adding TNF-alpha plus IFN-alpha led to the best yield. But, IFN-alpha alone did not increase the mature DCs compared to the control. CONCLUSION: We successfully cultured large quantities of mature DCs from PBMCs using GM-CSF and IL-4. IFN-alpha seems to have a synergistic effect when added with TNF-alpha, but further studies are required to prove the clinical significance.