ABSTRACT
The present study was aimed to investigate the pathways, by which IL-27 regulates the expression of adherent molecule Mac-1, chemotactic factor receptor fMLP-R and pro-inflammatory cytokine IL-1beta in human neutrophils. Highly purified human neutrophils were isolated from peripheral blood using Ficoll-Hypaque gradients centrifugation and erythrocyte lysis. The mRNA expression of IL-27 receptor components (WSX-1/TCCR and gp130) in human neutrophils was detected by reverse transcription polymerase chain reaction (RT-PCR). After incubation with IL-27 and specific inhibitors (p38 MAPK inhibitor SB203580, PI3K inhibitor LY294002 and ERK inhibitor U0126), the mRNA levels of fMLP-R and IL-1beta were determined by real time RT-PCR, and the adherent molecule Mac-1 expression in human neutrophils was determined by flow cytometry. The IL-1beta level in culture supernatant of human neutrophils was assayed by radioimmunoassay. The results showed that IL-27 receptor components (WSX-1/TCCR and gp130) were constitutively expressed in human neutrophils. IL-27 down-regulated Mac-1 expression in human neutrophils (p<0.05). After incubation with specific inhibitors, SB203580, not LY294002 and U0126, inhibited the down-regulation of Mac-1 expression by IL-27. However, IL-27 up-regulated the mRNA expression of fMLP-R and IL-1beta, and increased the release of IL-1beta (p<0.05). Interestingly, LY294002, not SB203580 and U0126, inhibited the up-regulation of fMLP-R and IL-1beta by IL-27. It is concluded that the IL-27 may regulate the expression of Mac-1, fMLP-R and IL-1beta in human neutrophils through p38 MAPK and PI3K signal pathways.
Subject(s)
Humans , Butadienes , Pharmacology , Chromones , Pharmacology , Down-Regulation , Imidazoles , Pharmacology , Interleukin-1beta , Metabolism , Interleukins , Metabolism , Macrophage-1 Antigen , Metabolism , Morpholines , Pharmacology , Neutrophils , Metabolism , Nitriles , Pharmacology , Phosphatidylinositol 3-Kinases , Metabolism , Pyridines , Pharmacology , Receptors, Formyl Peptide , Metabolism , Signal Transduction , Up-Regulation , p38 Mitogen-Activated Protein Kinases , MetabolismABSTRACT
The purpose of this study was to investigate the expression of human Factor IX (hFIX) in retrovirus-transfected human umbilical cord tissue derived mesenchymal stem cells (hUCT-MSCs). The pLEGFP-N1-hFIX vector was generated by cloning a 3.0 kb Bgl II-BamH I fragment from the pIRES2-EGFP-hFIX plasmid containing the hFIX cDNA and part of intron 1 of hFIX in pLEGFP-N1 vector. The retroviral supernatants were produced from the Phoenix packaging cell line and then infected the hUCT-MSCs. After selection with G418 for 10 day, the expression of FIX was detected by ELISA and Western blot. The biological activity of FIX was determined by the clotting assay employing human Factor IX-deficient plasma. The results showed that compared with the activity of pooled human normal plasma (100%), transduced cells produced biologically active hFIX with 100-130% activity in two-day culture supernatant and expressed hFIX at levels of 2.68 +/- 0.36 microg/10(6) cells/24 hours after G418 selection for 10 days. The secretion of hFIX into culture supernatant was also confirmed by Western blot analysis. It is concluded that genetically modified hUCT-MSCs can express biologically active hFIX and thus serve as an efficient drug delivery vehicle carrying hFIX used as a way of somatic gene therapy for hemophilia B.
Subject(s)
Humans , Cell Line , Factor IX , Genetics , Gene Expression , Genetic Therapy , Genetic Vectors , Mesenchymal Stem Cells , Retroviridae , Genetics , TransfectionABSTRACT
Bmi-1 is a transcriptional repressor, which belongs to the polycomb group family. It has been demon- started that over-expression of Bmi-1 occurs in a variety of cancers, including several types of leukemia. Bmi-1 gene plays a key role in regulation of self-renewal in normal and leukemic stem cells. Acute myeloid leukemic cells lacking Bmi-1 undergo proliferation arrest and show signs of differentiation and apoptosis, which leads to the proposal of Bmi-1 as a potential target for therapeutic intervention in leukemia. The purpose of this study was to investigate the effect of short hairpin RNA (shRNA) targeting Bmi-1 on functions of K562 cell line. The shRNA eukaryotic expression vector targeting Bmi-1 was constructed and transfected into K562 cells through lipofectamine 2000. The mRNA and protein levels of Bmi-1 were detected by PCR and Western blot respectively. The proliferation of K562 after Bmi-1 silencing was measured by using MTT assay and clone formation assay. The cell cycle was detected by flow cytometry. The results indicated that among the four shRNA designed, there was a shRNA which efficiently interfered with the expression of Bmi-1. The results of PCR and Western blot validated that the Bmi-1 gene of K562 cells transfected with such a Bmi-1 shRNA was suppressed successfully. Although levels of Bmi-1 mRNA and protein were significantly reduced, delivery of this siRNAs had no effect on cell viability or growth. Flow cytometry analysis suggested that Bmi-1 inhibition did not affect the cell cycle. It is concluded that the suppression of Bmi-1 expression is not able to reduce proliferation of K562 cells, suggesting existence of some other parallel signaling pathways, which are fundamental for leukemic transformation and are independent of Bmi-1 over-expression. Bmi-1 over-expression may play a secondary role in chronic myeloid leukemia transformation.
Subject(s)
Humans , Cell Proliferation , Cell Survival , Genetic Vectors , K562 Cells , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Genetics , Nuclear Proteins , Genetics , Polycomb Repressive Complex 1 , Proto-Oncogene Proteins , Genetics , RNA Interference , RNA, Small Interfering , Genetics , Repressor Proteins , Genetics , TransfectionABSTRACT
<p><b>OBJECTIVE</b>To determine whether mobilized peripheral blood mononuclear cells (M-PBMNCs) obtained from patients with diabetes was impaired in therapeutic neovascularization in limb ischemia, and to explore the pathological mechanisms of the impairment.</p><p><b>METHODS</b>Endothelial progenitor cells (EPC) were cultured in EGM-2MV, and then characterized by uptake of 1, 1-dioctadecyl-3, 3, 3, 3-tetramethylindocarbocyanine-labeled acetylated low density lipoprotein (Dil-AcLDL) and binding of ulex europaeus agglutinin (UEA). The number of EPC was compared between M-PBMNCs obtained from diabetic patients and those from normal subjects. M-PBMNCs obtained from diabetic patients, M-PBMNCs obtained from normal controls, or PBS were injected into the ischemic limbs of streptozotocin-induced diabetic nude mice. The limb blood perfusion was detected by laser Doppler blood perfusion imaging between these three groups in the following 1, 3, 7, 14, 21, and 28 days. Ambulatory score and ischemia damage were evaluated in the following 4 weeks. Capillary/fiber ratio was detected by CD31 or BS-1 lectin, and arteriole density was detected by alpha-smooth muscle actin (alpha-SMactin).</p><p><b>RESULTS</b>The number of EPC from diabetic patients were positively correlated with the blood perfusion (R = 0.486, P < 0.05) and capillary density (R = 0.491, P < 0.05), and the EPC number in diabetic patient were negatively correlation with their disease courses (R = - 0.587, P < 0.05). Transplantation of diabetic M-PBMNCs augmented the blood perfusion of ischemia hindlimbs, increased the capillary and arteriole densities, and promoted the collateral vessel formation. However, all the improvements were less significant in the diabetic patients than in the non-diabetic patients (P < 0.05).</p><p><b>CONCLUSION</b>Diabetes decreased the capability of M-PBMNCs to augment neovascularization in ischemia.</p>