The expression of CD14 in rat Kupffer cells

AIM: To explore the expression of CD14 in rat Kupffer cells (KCs). METHODS: In rat KCs induced by LPS or the mediators from KCs induced by LPS, the changes of CD14 expression were measured by RT-PCR and immunohistochemistry.The expressions of TNFα mRNA、IL-6 mRNA or the concentrations of TNFα、IL-6 were estimated by in situ hybridization and radioimmunoassay, respectively. RESULTS: LPS increased the expression of CD14 in KCs in a dose-dependent fashion (LPS, 1 μg/L-10 mg/L) and in a time-dependent fashion(0.5 h-24 h, peaked at 3-6 hours). While the expression of CD14 in KCs stimulated by the active mediators from KCs which had been exposed to LPS 1 hour were obviously increased. CONCLUSIONS: There was a close relationship between LPS or the active mediators from KCs induced by LPS and the expressions of CD14. It is implied that the increase in CD14 expression may be induced by LPS and the cytokines produced by KCs, it also reveals that there is a auto-regulated loop in CD14 expression.     

Fibronectin supports endotoxemia mice survival

AIM:To study the preventive effect of fibronectin on hepatic failure induced by endotoxin in mice.METHODS:The survival rate was observed in endotoxemia mice injected with fibronectin from human plasma. The tissue damage and expression of TNFα, IL-1β, IL-6 mRNA in hepatocyte were detected by the methods of histology, ultrastructure, DNA fragementation and RT-PCR.RESULTS:①Fibronectin obviously reduced the mortality of endotoxemia mice sensitized by D-galactosamine(GalN). ②Histopathology showed that less necrosis occurred on the hepatocyte of endotoxemia mice injected with fibronectin, compared with saline control. ③Ultrastructure and DNA fragmentation showed fibronectin suppressed hepatocyte apoptosis induced by LPS. ④Fibronectin down-regulated the overexpression of TNFα, IL-1β, IL-6 mRNA on hepatocyte induced by LPS.CONCLUSION:Fibronectin supports endotoxemia mice surrival by down-regulating the expression of TNFα, IL-β, IL-6, it may be a potent therapy for endotoxemia.     

Effects of eicosapentaenoic acid on expression of nuclear factor κB and release of cytokines in human umbilical vein endothelial cells stimulated by lipopolysaccharide

AIM: To investigate the effects of eicosapentaenoic acid(EPA) on the expression of nuclear factor kappa B(NF-κB) and release of vascular endothelial growth factor(VEGF), IL-1α and IL-6 in cultured human umbilical vein endothelial cells(HUVECs) stimulated by lipopolysaccharide(LPS).METHODS: HUVECs were obtained from cell strain and cultured in vitro. HUVECs were divided into 4 groups: control group, LPS group, 0.030 g/L EPA treatment group and 0.050 g/L EPA treatment group. The cells were cultured with LPS alone in LPS group and incubated with EPA for 1 h in the EPA pretreatment groups at the concentrations of 0.030 g/L and 0.050 g/L before LPS stimulation. Twenty-four hours after stimulated by LPS, the protein expression of NF-κB p65 in HUVECs were assessed by Western blotting analysis at different time points. The production of VEGF, IL-1α and IL-6 in cultured HUVECs was evaluated by ELISA. The effects of EPA on the protein expression of NF-κB p65 and the production of VEGF, IL-1α and IL-6 in HUVECs challenged by LPS were also determined.RESULTS: Compared with control group, the protein expression of NF-κB p65 was significantly increased in HUVECs induced by LPS and was inhibited by EPA. Compared with control group, the protein expression of VEGF, IL-1α and IL-6 was dramatically increased in HUVECs induced by LPS and most of the increase was inhibited by EPA.CONCLUSION: LPS enhances the protein expression of NF-κB and the release of VEGF, IL-1α and IL-6. EPA inhibits the protein expression of NF-κB, and the production of VEGF and the inflammatory cytokines in cultured HUVECs stimulated by LPS, indicating that EPA may be useful for preventing and treating neovascular and inflammatory diseases.     

Effect of antioxidant and NFκB on the induction of iNOS gene in rat pulmonary microvascular endothelial cells in vitro

AIM:To investigate the role of nuclear factor κB (NF_κB) in the induction of iNOS gene by TNFα and LPS in endothelial cells and the effect of antioxidant on the induction of iNOS. METHODS:Nitrite was determined based on Griess reaction. iNOS mRNA was analyzed using Northern blot. NF_κB in the cell nucleole was detected with electrophoretic mobility shift assay.RESULTS: (1)NO production and iNOS mRNA expression induced by LPS and TNFα was blocked by pyrrolidine dithiocarbamate(PDTC) or N-acetylcysteine(NAC). (2)LPS and TNFα triggered the activation and translocation of NF_κB, and PDTC or NAC inhibited the activation of NF_κB induced by LPS and TNFα. CONCLUSIONS:(1)The induction of iNOS gene by TNFα and LPS is dependent on the activation of NF_κB.(2)Antioxidants may inhibit the induction of iNOS gene through the inhibition of NF_κB activation.     

Expression of ephrin-A3 in lipopolysaccharide-induced proliferation of astrocytes

AIM: To explore the effects of ephrin-A3 expression on the proliferation of astrocytes induced by lipopolysaccharide (LPS).METHODS: Astrocytes from cerebral cortex of newborn rats were cultured and purified.The cells were exposed to LPS at the concentration of 10 mg/L and divided into 6 groups at random: control group (without LPS) and the groups of exposure to LPS for 30 min, 6 h, 24 h, 48 h and 72 h.The morphological changes of the astrocytes were observed under inverted phase-contrast microscope.The survival rate and apoptotic rate of astrocytes were measured by MTT method and AO/EB staining,respectively.The expression of ephrin-A3 and glial fibrillary acidic protein (GFAP) was measured by fluorescein staining with CY3.The changes of the inflammatory factors TNF-α and IL-6 in the culture supernatant were detected by ELISA.RESULTS: Compared with control group, the survival rates were notably increased, the apoptotic rates were notably decreased, the expression of ephrin-A3 and GFAP was significantly up-regulated and the inflammatory cytokines were significantly increased in the cells exposed to LPS at the concentration of 10 mg/L for 24 h, 48 h and 72 h.CONCLUSION: LPS promotes the proliferation of astrocytes.The expression of ephrin-A3 increases during the proliferation of astrocytes induced by LPS in rats.The mechanism may be related to inflammatory stimulation by cytokines.     

Protective effects of taurine on LPS-induced myocardial damage in rats

AIM: To investigate the effects of taurine on lipopolysaccharide (LPS)-induced myocardial damage in rats. METHODS: Healthy male SD rats (n=30) were randomly divided into control group (CON), LPS model group (LPS) and taurine treatment group (TAU). The rats in CON group and LPS group were intravenously injected with normal saline, and the rats in TAU group were injected with taurine (100 mg/kg). After 2 h, the rats in LPS group and TAU group were intraperitoneally injected with LPS at 10 mg/kg, and the rats in CON group were injected with normal saline. Six hours after injection of LPS, the blood samples were collected for determination of superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) levels. The myocardial tissues were processed for histological examination and the analysis of Western blot. RESULTS: Compared with CON group, LPS significantly reduced SOD activity in the serum and heme oxygenase 1 (HO-1) protein expression in the myocardial tissues, increased the serum content of MDA and levels of TNF-α and IL-6. LPS also significantly elevated the levels of TNF-α and IL-6, and up-regulated the cyclooxygenase-2 (COX-2) expression and phosphorylation of nuclear factor kappa B (NF-κB) in the myocardial tissues. Taurine pretreatment significantly elevated SOD activity and HO-1 protein expression level, decreased the levels of COX-2, TNF-α, IL-6 and phosphorylated NF-κB. Histological observation showed that taurine reduced inflammatory response in the myocardial tissue. CONCLUSION: Taurine attenuates LPS-induced myocardial damage in rats. The beneficial effects of taurine may be associated with its reduction of p-NF-κB/COX-2 signaling by activation of HO-1/CO.     

Effects of TNFα and IL-10 on cytomegalovirus infection in human embryonic lung fibroblasts

AIM:To study effects of tumour necrosis factor alpha(TNFα) and interleukin-10(IL-10) on human cytomegalovirus AD169 (HCMV AD169) infection in human embryonic lung fibroblasts (HEL),and the ability of the infected HEL to produce TNFα. We have attempted to understand the effect of cytokines in the immune of HCMV infection. METHODS:TNFα、IL-10 were added separately with different concentrations before 24 h HCMV infection of HEL to study the effect of TNFα and IL-10 on multiplication of HCMV. HCMV was incubated with HEL, TNFα in culture supernatants were measured at 4, 24, 48, 72, 96 h postinfection. The level of TNFα was measured by enzyme-linked immunosorbent assay( ELISA). RESULTS:The addition of TNFα with the concentration of 10-100 μg/L or IL-10 with the concentration of 1-10 μg/L before 24 h HCMV infection of HEL could remarkably inhibited the multiplication of HCMV in HEL. Level of TNFα didn't increase in infected cell supernatants. CONCLUSION:TNFα and IL-10 play an important role in the immune of HCMV infection.     

Mechanisms of nitric oxide synthesis induced by human complement C5b-9complex in glomerular mesangial cells of rats

AIM: To explore the mechanism of the nitric oxide (NO) synthesis induced by human C5b-9 complex in glomerular mesangial cells(MC) of rats. METHODS: The MC of rats were cultured and stimulated with human complement C5b-9 complex to induce TNFα and IL-1β. At the same time, several parameters related to NO synthesis were measured at 3 h, 6 h and 24 h after C5b-9 stimulation. The effects of monoclonal antibodies against TNFα and IL-1β on NO synthesis were examined in this system. RESULTS: TNFα concentration in supernatant from MC in C5b-9 group was higher than that of control group at 6, 24 h after stimulation with C5b-9 complex and reversed by adding anti-TNFα McAb. C5b-9 complex didn't stimulate the release of IL-1β in same system. In addition, the expression of iNOS mRNA in MC was observed at 3 h after stimulation with C5b-9. Levels of iNOS mRNA expression and cGMP in MC and NO₃^-/NO₂^- in supernatant from MC in C5b-9 group were higher than those in control group at 6, 24 h after C5b-9 stimulation, these changes were also reversed by adding monoclonal antibody against TNFα. CONCLUSION: C5b-9 complex could induce iNOS mRNA expression at 3 h after C5b-9 stimulation, and the synthesis of NO at 6, 24 h was related to TNFα released from cultured MC of rats by C5b-9 complex to a certain extent.     

Antagonistic effect of captopril on activation and injury of vascular endothelial cells induced by lipopolysaccharide

AIM: To investigate the antagonistic action of Captopril (Cap) on the activation and injury of human umbilical vascular endothelial cells (HUVECs) induced by lipopolysaccharide(LPS) and the possible mechanisms. METHODS: After 18 h exposure of the cultured HUVECs to LPS (1 mg/L), or LPS (1 mg/L) plus Cap at the concentration of 10^-7mol/L, 10^-5mol/L and 10^-3mol/L, the expression of vWF protein in the conditioned media was tested by enzyme-linked immunosorbent assay (ELISA), the expression of ICAM-1 protein in HUVECs was determined by indirect immunofluorescence technique with flow cytometry as well. In addition, the expression of TNFα mRNA was determined by in situ hybridization. RESULTS: The results of ELISA and indirect immunofluorescence technique showed that exposure to LPS at a concentration of 1 mg/L led to a significant increase in the vWF and ICAM-1 expression in HUVECs as compared to the control (P＜0. 05), whereas they were somewhat decreased when exposed to Cap at three increasing concentrations mentioned above, especially in the Cap (10^-3mol/L) plus LPS group (P＜0.05). Cap inhibited vWF secretion and ICAM-1 expression of HUVECs caused by LPS in a concentration-dependent manner. In situ hybridization revealed that the expression of TNFα mRNA was inhibited by Cap both in a concentration of 10^-3mol/L, and in a lower concentration of 10^-5mol/L. CONCLUSION: Cap antagonizes the activation and injury of HUVECs induced by LPS, which may be related to the decrease in TNFα mRNA expression.     

Bone marrow-derived mesenchymal stem cell-conditioned medium atte-nuates LPS-induced acute lung injury in mice

AIM:To explore the effects of bone marrow-derived mesenchymal stem cells-conditioned medium (MSCs CdM) on lipopolysaccharide (LPS)-induced acute lung injury. METHODS:Lung injury was induced in mice by intraperitoneal injection of LPS. The mice were given a tail vein injection of MSCs CdM or normal saline 1 h after LPS administration. The mice were killed by an intraperitoneal injection of pentobarbital 6 h after LPS injection for either bronchoalveolar lavage fluid (BALF) and serum collection or lung histological analysis. RESULTS:Compared with control group, the BALF levels of protein, interleukin-10 (IL-10) and keratinocyte growth factor (KGF), the serum levels of tumor necrosis factor α (TNF-α) and IL-6, and the myeloperoxidase (MOP) activity in the lung tissues were significantly higher in LPS group, and severe pathological damages in the lung tissues were also observed. Treatment with MSCs CdM significantly reduced the BALF prtein level, the seum TNF-α and IL-6　levels and the lung MPO activity, and attenuated the lung pathological damages, but further increased the levels of IL-10 and KGF in the BALF. CONCLUSION:Treatment with MSCs CdM attenuates the lung injuries induced by LPS, which may be via regulating the expression of TNF-α, IL-6, IL-10 and KGF.     

Effects of fosinopril,captopril and valsartan on the expressionof tissue factor in human monocytes

AIM: To investigate the effects of angiotensin-converting enzyme inhibitors (ACEI), fosinopril, captopril and angiotensin II AT₁ antagonists, valsartan on tissue factor (TF) expression on monocytes induced by lipopolysaccharide (LPS). METHODS: Mononuclear leukocytes from normal delivered female umbilical veins were incubated with bacterial LPS in presence or absence of different ACE inhibitors .At the end of incubation, the cells were disrupted by 3 freeze-thaw cycles. TF procoagulant activity was assessed by a one-stage clotting assay. RT-PCR was used to check TF mRNA expression, and GAPDH mRNA was used for parallel assay. RESULTS and CONCLUSION: The results showed that increased expression of TF mRNA induced by LPS was inhibited by fosinopril, captopril and valsartan, respectively, and the procoagualant activity of monocytes was also reduced.     

Effect of recombinant rat CC16 protein on LPS-induced expression of TNF-α, IL-6 and IL-8 in rat tracheal epithelial cells

AIM: To explore the effect of recombinamt rat CC16 protein (rCC16) on LPS-induced expression of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-8 in the rat tracheal epithelial (RTE) cells.METHODS: The RTE cells were incubated with rCC16 at concentrations of 0.5, 1.0 and 2.0 mg/L in serum-free media for 2 h prior to LPS (0.1 mg/L) treatment for further 24 h. The cells were harvested for assessing the mRNA levels of TNF-α, IL-6 and IL-8 by RT-qPCR. The cell culture supernatants were collected for analyzing the protein levels of TNF-α, IL-6 and IL-8 by ELISA. In addition, the nuclear translocation of nuclear factor-κB (NF-κB) p65 was tested by Western blot.RESULTS: rCC16 inhibited LPS-induced IL-6 and IL-8 expression at both mRNA and protein levels in the RTE cells in a concentration-dependent (0~2 mg/L) manner, as demonstrated by RT-qPCR and ELISA. However, no concentration-dependent manner between the dose of rCC16 and TNF-α expression was observed, and rCC16 inhibited LPS-induced TNF-α expression at lower concentration (0.5 mg/L). rCC16 concentration-dependently inhibited the effects of LPS on the level of nuclear translocation of NF-κB p65.CONCLUSION: rCC16 suppresses LPS-mediated TNF-α, IL-6 and IL-8 production through inactivation of NF-κB activity in RTE cells.[KEY WORDS] CC16 protein; Airway inflammation; LPS; Inflammatory mediators; Nuclear factor-κB     

Effect of IL-12 on the expression of Fas/FasL and TNFα

AIM:To study the effect of IL-12 on T lymphocytes apoptosis, the expression of Fas/FasL and TNFR/TNFα. METHODS:Terminal dUTP nick end labeling(TUNEL) and Annexin V assay were used. Anti-TNFR were labeled with FITC, anti-CD95 was labeled with PE and Anti-FasL with biotin. Three kinds of T cells (HTB176,TIB152 and human normal T cells) were analysed through flow cytometry. RESULTS:At 1st hour after being treated with IL-12, the expression of FasL protein and FasL mRNA in HTB176 and TIB152 began to increase and reached peak value in 24 hours. In the normal T cells, FasL just began to increase in 1 hour and maintained stability in 6, 12 and 24 hours through the later experiment period. All three kinds of T cells displayed no change in the expression of CD95 and TNFR/TNFα under the stimulation of IL-12. CONCLUSION:Expression of such apoptosis regulating factors were different in the apoptosis of T cells induced by IL-12.     

Mechanisms underlying protection of mouse myocardium against LPS-induced injury by Siduqing

AIM: To investigate the protective effect of Siduqing, a Chinese medicine, on LPS-induced myocardium injury in mice and its mechanisms. METHODS: Mice were divided into 4 group: control, LPS, Siduqing treatment and Siduqing group, and administered intragastrically with Siduqing decoction or distilled water (0.2 mL/10 g) twice a day for 3 days, two hours after Chinese herbal medicine treatment on day 3, LPS (30 mg/kg) or normal saline was injected intraperitoneally. The serum creatine kinase (CK) and myocardial superoxide dismutase (SOD) activities were determined, and myocardial tumor necrosis factor α (TNFα) and malondialdehyde (MDA) contents were also detected. In addition, the histological changes and ultrastructure of heart were examined. RESULTS: Histological examination showed edema in myocardium and architectural disarray at 12, 24 h after LPS injection, mitochondrial swelling, condensation and margination of chromatin, irregular nuclear envelope and loss of contractile filaments at 24 h post LPS administration, while Siduqing treatment attenuated the above pathological changes of myocardium. CK activity in serum and myocardial TNFα content were higher in LPS group than control and Siduqing treatment group. Myocardial SOD activity in siduqing treatment group was higher than that in LPS group, but there was no difference in myocardial MDA content between control, LPS and Siduqing treatment group. CONCLUSION: These data suggest that Siduqing protects myocardium against LPS- induced injury via inhibiting myocardial TNFα production.     

Changes of Ski expression levels in rat activated astrocytes

AIM: To explore the time-dependent change of Ski protein expression in normal and activated astrocytes in rats.METHODS: The astrocytes were obtained from rat cerebral cortex and cultured in vitro. The astrocytes were treated with LPS and scratch injury for activation. Western blot analysis was used to determine glial fibrillary acidic protein (GFAP) and Ski protein levels in activated astrocytes at a series of time points. The indirect immunofluorescence staining method was performed to detect the location of Ski protein in the astrocytes.RESULTS: The protein of GFAP was naturally expressed in the astrocytes, beginning to increase after treated with LPS and scratch injury. Little protein expression of Ski in the normal astrocytes was observed. The Ski protein expression began to increase after treated with 1 mg/L LPS, peaked at 4 d (P<0.05) and then deceased, but was stills higher than that in the normal cells. The protein expression level of Ski after scratch injury was highly consistent with above mentioned. Ski was mainly observed in the nucleus of the normal cells and the cells treated with LPS for 6 d, while it was observed in the cytoplasm 2 and 4 d after treated with LPS.CONCLUSION: The protein of Ski is expressed in the astrocytes, and the expression level is increased in activated astrocytes, mainly located in the nucelus. Ski may plays an essential roles in the processes of activation and proliferation of astrocytes.     

Effects of Ginsenosides on LPS-induced TF and PAI-1 expression in vascular endothelial cells

AIM: To study the effect of ginsenosides on lipopolysaccharide-induced expression of tissue factor (TF) and plasminogen activator inhibitor type-1 (PAI-1) in vascular endothelial cells (EC), and to investigate the mechanism of ginsenosides in the healthy protection and treatment of cardiovascular diseases. METHODS: Human umbilical vein endothelial cells (HUVEC) were cultured by trypsin digestion method. PAI-1 was measured in the conditioned medium of HUVEC by a specific enzyme-linked immunosorbent assay (ELISA), whereas TF activity was measured in the lysates of these cells by a single step clotting assay. Specific mRNA expressions were determined by Northern blotting. RESULTS: Treatment of HUVEC with LPS resulted in a significant increase in PAI-1 antigen and TF activity. Ginsenosides inhibited this LPS-induced upregulation of PAI-1 protein and TF activity in HUVEC. These effects were also confirmed on the level of specific PAI-1 and TF mRNA expression by Northern blotting. CONCLUSION: Ginsenosides counteract endothelial cell activation by inhibition LPS-induced PAI-1 and TF expression in these cells. This ability of ginsenosides might explain its efficacy in the healthy protection and the treatment of cardiovascular diseases.     

Artemisinin attenuates intestinal epithelial barrier damage induced by LPS

AIM: To investigate the effect of artemisinin on lipopolysaccharide(LPS)-induced intestinal epithelial barrier damage in IEC-6 cells and its molecular mechanism. METHODS: Cultured IEC-6 cells were divided to 5 groups: control group, LPS(100 mg/L) group and LPS+Artemisinin(30, 50 and 100 μmol/L) groups. The cytotoxicity was detected by MTT assay. The releases of TNF-α, IL-1β and IL-6 in the IEC-6 cells were measured by ELISA. The transepithelial electrical resistance(TER) was detected by electrical resistance tester, and the horseradish peroxidase(HRP) flux permeability were analyzed by a microplate reader. The expression of tight junction proteins, ZO-1, claudin-1 and occludin, and the expression of TLR4/MyD88/NF-κB at mRNA and protein levels were determined by RT-qPCR and Western blot. RESULTS: Artemisinin alone(up to 100 μmol/L) or in combination with LPS(100 mg/L) was not toxic to IEC-6 cells. Compared with control group, the releases of TNF-α, IL-1β and IL-6 in the culture supernatant of IEC-6 cells significantly increased after treatment with LPS. The expression of TLR4/MyD88/NF-κB was activated by LPS. LPS down-regulated the protein expression of ZO-1, claudin-1 and occludin. However, artemisinin treatment decreased the releases of TNF-α, IL-1β and IL-6 in the culture supernatant of IEC-6 cells. The expression of TLR4/MyD88/NF-κB at mRNA and protein levels was gradually reduced after treatment with artemisinin. In addition, artemisinin upregulated the protein expression of ZO-1, claudin-1 and occludin significantly(P<0.01) in a dose-dependent manner. CONCLUSION: Artemisinin attenuates LPS-induced intestinal epithelial barrier damage by inhibiting TLR4/MyD88/NF-κB activation in the IEC-6 cells.     

Effects of Fas,NF-κB and caspases on microvascular endothelial cell apoptosis induced by TNFα

AIM:To study the apoptotic effect of TNFα on rat pulmonary microvascular endothelial cells(PMVEC)and the role of Fas, NF-κB in its mechanism. METHODS: Apoptosis of PMVEC was analyzed and quantitated with TUNEL, flow cytometer. Northern blot was applied to assess the influence of TNFα on PMVEC Fas expression. Fas antibody was used to investigate the apoptotic effect of Fas on PMVEC. Activation of caspase-8 was examined by Western blot. Expression of caspase-3 was analyzed with histo-immunochemical staining. RESULTS:Growth curve showed that TNFα suppressed endothelial cell proliferation in a dose-dependent manner. After treatment with 5×10⁶U/LTNFα, apoptotic rate was 14.0%±3.1% detected with TUNEL, and 13.1% with flow cytometer. When the cells were co-cultured with TNFα and APDC, an NF-κB inhibitor, less cells were viable and more cells were positively stained with TUNEL. Fas expression in PMVEC was elevated after TNFα treatment. Co-culturing with Anti-Fas antibody aggravated PMVEC apoptosis. Caspase-8 activity and caspase-3 expression was elevated. Caspase-3 inhibitor significantly ameliorated PMVEC apoptosis. CONCLUSION: Large dose of TNFα(5×10⁶U/L) can induce apoptosis in rat PMVEC. NF-κB has an anti-apoptotic effect in PMVEC. TNFα up-regulates Fas expression in PMVEC, and the latter takes a part in apoptosis. Caspase-8 and caspase-3 are involved in PMVEC apoptosis induced by TNFα.     

Expression of cytokines and their receptors in leukemia cell lines and normal blood cells

AIM: To study the expression of cytokines and their receptors in leukemia cell lines and normal blood cells. METHODS: RT-PCR was used to detect expression of mRNA for cytokines in leukemia cell lines(HL-60,U937,K562,HEL,DAMI,MEG-01,HUT78 and CA) and normal blood cells, including CD34⁺ cells, megakaryocytes,platelets, peripheral mononucleates cells and granulocytes. RESULTS: ①CD34⁺ cells simultaneously expressed mRNA for IL-1(α,β),IL-3, IL-6 , G-CSF, GM-CSF and their receptors and SCFR,MPL as well. The granulocytes only expressed IL-6,IL-6R,G-CSFR,GM-CSF. Megakaryocytes and platelets only expressed IL-3R,IL-6,IL-6R,MPL.Interestingly, TGFβ₁ ,TNFα and their receptors sustained to express in normal cells.②Most leukemia cell lines were found to simultaneously express at least two or more stimulating cytokines and receptors ,while TGFβ 1 , TNFα and their receptors were expressed in all the leukemia cell lines we observed. CONCLUSIONS: ①Multi-autocrine loops exist in leukemia cells;②Imbalance of autocrine loops of positive and negative cytokines may be related to leukemia.