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1.
AIM:To investigate the inhibitory effect of quercetin on in vitro activation of T lymphocytes by polyclonal activators with CD69 expression as an activation marker.METHODS:After being separated from lymphoid nodes of a C57BL/6 mouse, the lymphocytes were exposed to polyclonal activators (PDB or Con A) with or without quercetin. Then they were harvested at 2 h, 6 h and 24 h, respectively. The expressional rates of CD69 on T lymphocytes were assessed by two-color immunofluorescent staining and flow cytometry, and the inhibitory rates of quercetin at different time points were estimated.RESULTS:Quercetin had no effect on the expressional rate of CD69 on T lymphocytes under resting states. After the stimulation with PDB or Con A, the expressional rates of CD69 on T lymphocytes in the present of quercetin (10 μmol/L) showed significant decrease compared with those of control groups at different time points (P<0.01). The inhibitory rate of quercetin on CD69 expression stimulated by PDB dropped sharply from 2 h to 24 h, whereas the inhibitory rate of quercetin on Con A action were relatively stable.CONCLUSION:Quercetin has inhibitory effects on the activation of T lymphocytes by Con A or PDB, suggesting that the action site of quercetin may be on PKCθ or its downstream. Furthermore,these inhibitory effect seems to be reversible.  相似文献   

2.
AIM: To investigate the details of CD4+ T cell polarized to Th1/Th2 in vitro. METHODS: After isolated the PBMCs and blood-plasma from adult human peripheral blood by Ficoll-Hypaque centrifugation, the PBMC culture procedure with or without the self-blood -plasma was applied to polarize T cells in vitro, these cells were polarized by PHA(20 mg/L),non-PHA respectively. The polarized rates of Th cell after 24 h,48 h,72 h were estimated respectively by flow cytometry following two-color immunofluorescent staining. RESULTS: CD4+T cell would polarize to Th1/Th2 two subsets after self-cytokines and PHA activation in vitro. The polarized rates of T cell after cultured for 24 h,48 h and 72 h were (13.28%±1.59%)/(12.70%±1.65%),(17.19%±1.03%)/(17.50%±1.30%),(19.49%±2.87%)/(18.58%±1.49%) respectively, but the polarized rates of T cell were very low if without self-blood-plasma. The difference between them was significant. The ratios of Th1/Th2 cells were about 1. CONCLUSION: CD4+T cell from adult human peripheral blood would polarize to Th1/Th2 two subsets in the presence of self-blood-plasma and PHA(20 mg/L) in vitro, and the cell number of Th1 and Th2 would be in balance.  相似文献   

3.
AIM: To study the effects of [8-(diethylamino) octyl-3, 4, 5 -trimethoxybenzoate] (TMB-8), an intracellular Ca2+ antagonist, on the activation, proliferation and cell-cycle distribution of the mouse T lymphocytes stimulated by concanvalin A (Con A) in vitro. METHODS: After stimulated with Con A, T cells were treated with different concentrations of TMB-8 alone and its combination with cyclosporine A (CsA). The expression of CD69, the early marker of CD3+ T cell activation, was measured by FACS. The proliferation-related index was determined by carboxyl fluorescin diacetate succinmidyl ester (CFDA-SE) flow cytometry. The cell-cycle distribution was analyzed by propidium iodide staining.RESULTS: After 6 h culture, the activation rate of CD69+ T cell in Con A group was (74.88±1.88)%. 10, 20 and 40 μmol/L of TMB-8 inhibited the expression of CD69 (P<0.01), especially in 40 μmol/L (52.55%±1.54%). After 48 h and 72 h culture, the PI of Con A group was 1.24±0.01, 2.05±0.07, respectively. TMB-8 with the concentration up to 5 μmol/L exerted a definite inhibitory effect on the proliferation with a maximal inhibition in 40 μmol/L(P<0.01). In the combination of 10 μmol/L of TMB-8 with 25 μg/L of CsA, an evident synergistic effect was observed (P<0.01). Moreover, the cell-cycle distribution analysis showed that after 48 h culture, the concentration of TMB-8 over 10 μmol/L showed an evident suppression in S phase.CONCLUSION: TMB-8 significantly inhibites the early steps of the Con A-induced T cell activation and proliferation, as well as the progression of T lymphocytes in S phase.  相似文献   

4.
AIM: To study the effect of genistein on activation and proliferation of T cells, and explore the molecular mechanism of genistein. METHODS: Fluorescence conjugated monoclonal antibodies and flow cytometry were used to detect the express of CD69 and CD25 by activated T cells in vitro in response to Concanavalin (ConA )and Phorbol 12, 13-dibutyrate(PDB) or T cell proliferation stained by CFSE in response to PDB / Ionomycin or ConA. RESULTS: Genistein inhibited the expression of CD69 and CD25 in activated T cells in response to Con A in a concentration-dependent manner and in response to PDB in a high concentration. Genistein inhibited proliferation of T cells in both groups in a concentration-dependent manner. CONCLUSION: Genistein inhibited activation and proliferation of T cells in vitro in response to polyclonal stimulus, and it may hold potential as a new immunosuppressant.  相似文献   

5.
AIM: To investigate the effect of berberine (Ber) on the activation and proliferation of T lymphocytes and its mechanism of action. METHODS: Whole peripheral blood from normal subjects was stimulated with phytohemagglutinin (PHA) or phorbol ester (PDB) plus ionomycin (Ion) and the expression levels of CD69 and CD25 were evaluated with flow cytometry after the staining with appropriate fluorescent monoclonal antibody. The distribution of cell cycles was analyzed by propidium iodide staining and dead cells by 7-aminoactinomycin live staining. RESULTS: 100 μmol/L and 50 μmol/L of Ber had significant inhibition of the expression of CD69 on T cells stimulated with PDB plus Ion or PHA, while effect of 25 μmol/L Ber was not significant. And as time of action extended, the extent of inhibition decreased. For the expression of CD25, Ber at the concentrations as above all exerted significant inhibitory effect in a dose-dependent manner. Moreover, Ber could block lymphocytes cell cycle progression from G0/G1 phase to S and G2/M phase without phase specificity. Besides, live staining analysis revealed that Ber did not have significant cytotoxicity on lymphocytes. CONCLUSIONS: Ber significantly inhibits the expression of early and mid activation antigens of T cells and also blocks the progression of lymphocytes cell cycles. These results suggest that Ber exerts immunosuppression effect through inhibiting the activation and proliferation of T cells.  相似文献   

6.
AIM:To investigate the influences of protein kinase C(PKC) inhibitors on the expression of interleukin-2(IL-2) and interferon-γ(IFN-γ) byin vitro activated T-lymphocytes. METHODS:Double fluorescent staining together with flow cytometry was adopted to detect intracellular cytokines and to analyze the effects of H7 and gossypol on IL-2 and IFN-γ expression levels of T-lymphocytes stimulated with phorbol ester (PDB)+ionomycin(I) in the presence of monensin.RESULTS:The expression rates of IL-2 and IFN-γ of CD3+ T cells stimulated with PDB+I for 4 h were 16.64±2.04 and 25.81±3.53(x±s), respectively, which were significantly higher than that of control (1.06±0.22 and 3.12±0.77)(P<0.05). Gossypol was able to inhibit the expression of IL-2 and IFN-γ significantly, with the expression rates of 2.08±0.12 and 9.01±1.90, respectively. At the presence of 50 μmol/L H7, the rates of IL-2+ and IFN-γ+ CD3+ T cells were 0.43±0.06 and 2.40±0.27, respectively. The effect of H7 was stronger than that of gossypol. CONCLUSION:PKC plays an important role in the expression of IL-2 and IFN-γ of CD3+T cells and its inhibitors H7 and gossypol exert significant inhibitory effect on the expression of these two cytokines. It is suggested that H7 and gossypol may have modulatory effect on T-cell-dependent specific immune responses by inhibiting PKC activity.  相似文献   

7.
AIM:The expression of CD28, CD56 and CD57 on CD8+T cells in the peripheral blood of young (age range 20-35) and elderly(age range 60-75) healthy donors were compared to explore the change of the cellular immune function with aging.METHODS:Three-color fluorescent flow cytometry was performed to analyze the differences in percentage of CD8+CD28+, CD8+CD56+ and CD8+CD57+T cells in the peripheral blood between the young and elderly groups.RESULTS:CD8+CD28+T cells in the peripheral blood of the elderly group was significantly lower than those in the young group, with percentage of 34.07±5.28 and 49.84±7.43,respectively (P<0.05). Conversely, CD8+CD56+T cells and CD8+CD57+T cells in the peripheral blood of the elderly group were significantly higher than those in the young group, and the percentage was 6.60±2.40 vs 2.10±0.35,41.82±6.01 vs 22.89±2.80, respectively(P<0.05).CONCLUSION:The expression of CD28, CD56 and CD57 on the CD8+T cells in the peripheral blood are changed significantly with aging. The decrease in CD28 expression may play an important role in the immunosenescence, while the increase in CD56 and CD57 expression seems to be a compensatory adaptation for the immune dysfunction.  相似文献   

8.
AIM: To investigate the produce of intracellular cytokine following short-term in vitro stimulation with vMIP and LPS, and discuss the effect of vMIP to cellular immunity. METHODS: The methods of Cross-linking of radioactivity, ELISA and four-colors flow cytometer were used to test the level of the secretion of chemokine IL-12 and intracellular cytokine IFN-γ and IL-4. RESULTS: After treated the PBMCs with vMIP-II, the levels of secretion of IL-12, IFN-γ and IL-4 were reduced in the present of LPS by competitively combining chemokine receptor; vMIP promoted CD4+T cell to secrete IL-12, IFN-γ and IL-4. CONCLUSION: vMIP-II can protect systemic response of immunity and reduce extremely inflammation by down-regulating proinflammation.  相似文献   

9.
AIM:To study the effects of thrombopoietin(TPO) and other hematopoietic cytokines on platelet activation. METHODS: Using fluorescent-labeled monoclonal antibodies and flow cytometry. RESULTS:The percentage range of platelets activated by 120 ng/mL TPO was 8.89%~39.92%,mean value was 17.43%; However,there were no effects of TPO 40 ng/mL and GM-CSF 100 ng/mL and IL-3 100 ng/mL on platelet activation. CONCLUSION:Higher concentration of TPO directly stimulated platelet activation.  相似文献   

10.
AIM:To investigate the expression of Th1-typed cytokine IFN-γ and Th2-typed cytokine IL-4 on T lymphocytes that infiltrate in nasal polyps for searching the pathogenesis of nasal polyps. METHODS:Nasal polyps tissue samples and peripheral blood were obtained from 21 patients. Normal human inferior turbinate mucosa and peripheral blood were obtained as well. Flow cytometry was adopted to detect the expression of IFN-γ and IL-4 of T lymphocytes. RESULTS: Th cytokines were rarely detected in inferior turbinate from normal human. Nasal polyps tissue consisted of abundant T lymphocytes. The expression of IL-4 and IFN-γ increased in peripheral blood from patients compared with normal human (P<0.05). The expression of IL-4 increased but the expression of IFN-γ decreased in nasal polyps compared with that of peripheral blood from the same patient (P<0.05). CONCLUSION:There were generous of T lymphocytes infiltrating in nasal polyps. There was abnormal immune status in the local nasal mucosa from the patients, and the predomination of Th cytokine secretion changed compared with peripheral blood from the same patients, which resulted in the change of microenvironment of nasal mucosa and possibly close related to the formation of nasal polyps.  相似文献   

11.
AIM: To prepare an improved medium for culturing human cardiac stem cells. METHODS: The heart samples of the right auricle obtained from the patients after cardiac surgery were minced into pieces (about 1 mm×1 mm×1 mm), digested and cultured. The primary cells obtained were cultured with improved cardiosphere-growing medium (CGM) for proliferation, and the cells were identified by flow cytometry. Finally, purer c-kit+ cells were obtained by the method of magnetic bead sorting. RESULTS: After about 2 weeks of culture, small, round and phase-bright cells migrated from the well-adherent explants over a layer of fibroblast-like cells. These cells were collected by a brief digestion with Accutase, washed and cultured with improved CGM. No significant difference of the proliferative capacity between using traditional CGM and improved CGM was observed. After subculture and proliferation, the identification result by flow cytometry showed that the positive rate of c-Kit surface marker on these cells was (6.8±2.1)%. By the method of anti-c-Kit magnetic bead sorting, purer c-Kit+ cardiac stem cells were obtained and differentiated into cardiomyocytes. CONCLUSION: Purer c-Kit+ cardiac stem cells are isolated with the improved CGM culture.  相似文献   

12.
AIM: To observe the effect of salidroside on behaviors of primary mouse T-lymphocytes in vitro. METHODS: The lymphocytes from the lymphoid nodes of BALB/c mice were isolated and primarily cultured. The viability of T cells was assessed by MTT assay. Fluorescence-conjugated monoclonal antibody and flow cytometry (FCM) were used to analyze the expression of T-cell activation marker CD69 in response to concanavalin A (Con A) in vitro. Carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) staining was used to detect the proliferation of T cells in vitro. FCM analysis was used to determine the production of reactive oxygen species (ROS) in the T cells by staining with 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA). The mean fluorescence intensity of DiOC6(3) staining in the T cells was detected by FCM in order to analyze the effects of salidroside on the activity of the mitochondrial and the mitochondrial membrane potential in the T cells induced by dexamethasone (DEX). The thymus T cells from BALB/c mice were isolated and primarily cultured, and then FCM was also used to analyze the apoptosis of the thymus T cells treated with DEX. RESULTS: Salidroside increased the expression of T-cell activation marker CD69 at the final concentration of 80, 160 and 320 μmol/L (P<0.05). Salidroside promoted the proliferation of T cells induced by Con A for 72 h in vitro (P<0.01). Salidroside reduced the production of ROS (P<0.05) and protected the mitochondrial membrane potential of T cells from the injury of DEX (P<0.01). Salidroside also decreased the apoptosis rate of the thymus T cells induced by DEX in vitro (P<0.01). CONCLUSION: Salidroside promotes the activation and proliferation of T cells induced by Con A, reduces the production of ROS, maintains the mitochondrial membrane potential and protects thymus T cells against apoptosis induced by DEX in vitro.  相似文献   

13.
AIM: To study the influence of status of stimulator cells on activation of responder T cells in mixed lymphocyte reaction (MLR), so as to provide some basis for clinical transplantation. METHODS: Stimulator cells were pretreated differently before mixed lymphocyte culture (MLC) to change their functional status, fluorescence conjugated antibodies and flow cytometry were used to detect expression of CD69 by responder T cells at several different time points.RESULTS:The expression percentages of CD69 by responder T cells in MLCa group(stimulator cells were pre-activated)were significantly higher than those in MLC group(stimulator cells were not pre-activated)at 24,48and 72 hours of culture,respectively(5.21%±0.24%vs 1.98%±0.33%,29.81%±0.85%vs 20.65%±1.00%and 39.61%±1.62%vs 13.49%±0.60%,P<0.01). CONCLUSION: Our results showed that with pre-activated stimulator cells, expression of CD69 by responder T cells could be significantly elevated in MLR.  相似文献   

14.
AIM: To investigate whether viable apoptotic cells and phagocytosis of them affect the activation of T lymphocytes. METHODS: Ultraviolet irradiation was used to induce apoptotic cells in vitro and the model of phagocytosis of these cells was established. Cytokine TGFβ1 was detected by ELISA. The rate of apoptotic cells and phagocytosis of them were assessed by flow cytometry. Furthermore, flow cytometry was also employed to examine the expression of activation signs, such as CD69, CD25, CD71, of T lymphocytes under the intervention of apoptotic cells and macrophage which ingested apoptotic cells, to reflect whether the apoptotic cells and the phagocytosis of these cells could influence the activation of lymphocytes stimulated by Con A. RESULTS: Ingestion of apoptotic cells increased TGFβ1 secretion. Only the macrophages that had ingested apoptotic cells could suppress the activation of lymphocytes. The expression of the markers of lymphocytes activation such as CD69, CD25, CD71 had been restrained. These inhibition effects were abolished by monoclonal anti-TGFβ1 antibody. CONCLUSION: The macrophages that have ingested apoptotic cells inhibit expression of CD69, CD25 and CD71 of T lymphocytes stimulated by ConA. This effect is dependent on the increase in TGFβ1 secretion in local site.  相似文献   

15.
AIM: To construct a rAAV2-pigment epithelium-derived factor (PEDF) vector and to explore the effect of rAAV2-PEDF on the migration and apoptosis of human retinal capillary endothelial cells (HRCECs). METHODS: PEDF gene was cloned into an adeno-associated virus vector pSNAV. The recombinant pSNAV-PEDF was transfected into BHK cells. The G418 resistant cells were selected and infected with recombinant HSV which packaged the recombinant pSNAV-PEDF. The high-titer rAAV2-PEDF was obtained by purification. After transfected the rAAV2-PEDF into HRCECs, the protein expression of PEDF were detected by Western blotting, the migration of HRCECs was assessed by a boyden chamber, and the apoptosis of HRCECs was analyzed by flow cytometry. RESULTS: The evaluation results of PCR, enzyme digestion, and DNA sequencing showed that the rAAV2-PEDF was constructed correctly. The GFP positive cells were observed under laser scanning confocal microscope 48 h after rAAV2-GFP transfection. The expression level of PEDF protein was higher in experimental group than that in control group. The number of migrated cells was 33.0±2.7 in normal control group, 35.0±3.6 in rAAV2-GFP treatment group, and 12.0±2.1 in rAAV2-PEDF treatment group (P<0.05). In normoxic condition, the apoptotic cells were 2.10%±0.53% in control group, 3.40%±0.62% in rAAV2-GFP group and 1.60%±0.47% in rAAV2-PEDF group (P>0.05). In hypoxic condition, the apoptotic cells were 4.00%±0.55% in CoCl2 treatment group, 6.10%±0.71% in CoCl2+rAAV2-GFP treated group and 40.00%±2.10% in CoCl2+rAAV2-PEDF treatment group (P<0.05). CONCLUSION: rAAV2-PEDF is successfully constructed and PEDF gene is stably expressed in HRCECs after rAAV2-PEDF transfection. Over-expression of PEDF inhibits the migration of HRCECs and induces the cell apoptosis obviously in hypoxia.  相似文献   

16.
AIM: To investigate the inhibitory effects of cholecystokinin octapeptide (CCK-8) on nuclear factor-κB (NF-κB) activities stimulated by lipopolysaccharide (LPS) by using forskolin, the activator of adenylate cyclase, and PKA inhibitor H-89 in rat pulmonary interstitial macrophages (PIMs).METHODS: PIMs were isolated and purified.EMDA was applied to detect NF-κB activities and Western blotting was used to analyze the IκB-α protein level in rat PIMs.RESULTS: The NF-κB activity was not detected in normal control rat PIMs.The NF-κB activity in LPS-treated rat PIMs was obviously higher than that in control group (P<0.01).The IκB-α protein level in endochylema decreased obviously compared to control group (P<0.01).No obvious change of NF-κB activity and IκB-α protein level in CCK or Fsk treated rat PIMs was observed (P>0.05).The NF-κB activity in CCK+LPS group and LPS+Fsk group were obviously lower than that in LPS group (P<0.05).The IκB-α protein level was obviously higher (P<0.01).In LPS+CCK+H-89 group, the NF-κB activity in rat PIMs was obviously higher than that in CCK+LPS group (P<0.01), while the IκB-α protein level decreased (P<0.01).CONCLUSIONS: The activation of cAMP-PKA signaling pathway inhibits the increase in NF-κB activity and the decrease in IκB-α protein level stimulated by LPS in rat PIMs.The anti-inflammatory effects of CCK-8 were taken effect by activating cAMP-PKA signaling pathway and further inhibiting the NF-κB activity.  相似文献   

17.
AIM: To investigate the effect of sodium nitroprusside (SNP) on activation of nuclear factor κB. METHODS: The techniques of culture of human T lymphocytes, Western blot and RT-PCR were applied. The effects of NO donor sodium nitroprusside (SNP) at different concentrations on mRNA and protein expression of IκBα in human T lymphocytes at 30 min or 120 min after stimulating with phytohaemagglutinin (PHA-P) were observed. RESULTS: SNP at middle or high concentrations reduced the degradation of κIBαprotein 30 min after stimulating with PHA-P,and increased the re-expression of κIBαmRNA 120 min after stimulating with PHA-P significantly.CONCLUSION: The mechanism of inhibitory effect of SNP at middle or high concentrations may be due to the decrease in degradation and the increase in re-synthesis of κIBα.The regulatory mechanism of SNP at low concentration may not be through κIBα.  相似文献   

18.
AIM: To evaluate the effects of lactacystin (LAC) and β-lactacystin (β-LAC), proteasome inhibitor, on the proliferation and activation of T lymphocytes. METHODS: Flow cytometry was used to analyse the proliferation and the expression of CD69, CD25 and CD3 in PHA activated T-lymphocytes. Furthermore, the expression of PA28 and IL-2 mRNA were assayed by competitive RT-PCR. RESULTS: (1) LAC and β-LAC significantly decreased the incorporation in PHA activated T-lymphocytes. (2) Although LAC and β-LAC did not affect the expression of CD69 at any time, they significantly inhibited the expression of CD25 (48 h, 72 h, P<0.05). (3) In comparison with control, LAC and β-LAC significantly down-regulated the expression of PA28 and IL-2 mRNA (48 h, 72 h, P<0.05).CONCLUSIONS: LAC and β-LAC significantly inhibit the proliferation and activation of T lymphocytes. Mechanisms involved are inhibition of CD25 and down-regulation of PA28 and IL-2 mRNA expression.  相似文献   

19.
AIM:To investigate the details of age-related changes of T lymphocytes in order to seek for sensitive biomarker for immunosenesence.METHODS:Heparin anticoagulated venous blood was collected freshly from young (20-35 years) and elderly (50-75 years) volunteers and three or four color immunofluorescence staining was performed. The nucleated cells were acquired and the phenotypes of T lymphocyte subpopulations were analyzed with flow cytometry.RESULTS:There was no significant difference in percentages of pan-T (CD3+), helper T (CD4+) and cytotoxic (CD8) T subsets between young and elderly, whereas the density of CD3 molecule (MFI) on T cells in elderly group decreased significantly. It was also found that the rates of CD44+ and CD62L+ T cell subsets in young group did not have statistical difference from elderly. However, the rates of CD95+ pan-T, helper T and cytotoxic T subsets of elderly group were all markedly higher than that in young group.CONCLUSIONS:The relative rates of T cell and its subsets displayed no age-related changes while the density of CD3 was down-regulated during aging in these groups investigated. Moreover, the expression percentage of CD95 (Fas) on T cells increased as aging, suggesting that it is a potential biomarker for evaluating immunosenescence.  相似文献   

20.
AIM: Detection and enrichment of T lymphocytes after allogeneic PBMNC stimulation according to secreted cytokine were performed in order to explore a new approach for studying allogeneic reactive T lymphocytes. METHODS: The novel cytokine secretion assay (CKSA) was applied to detect T lymphocyte secreting IFN-γ, IL-4 and IL-10 at single cell level in human mixed lymphocyte reaction. IFN-γ secreting T cells were enriched by means of magnetic sorting system. RESULTS: Allogeneic PBMNC stimulation didn't alter the proportion of IL-4 and IL-10 secreting T lymphocytes (which were 0.12%±0.03% and 0.10%±0.03%, respectively), but increased proportion of IFN-γ secreting T lymphocytes (1.12%±0.13%). These IFN-γ- secreting T lymphocytes could be further enriched to 67.3%±10.5% . CONCLUSION: It is feasible to detect significantly increased IFN-γ-secreting T cells after allogeneic PBMNC stimulation based on the novel CKSA technique, and these cells could be efficiently enriched for further use.  相似文献   

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