Association between development of CD4+CD25+ regulatory T cells and thymus CD4-CD25+ cells

AIM: To explore the correlation between development of CD4⁺CD25⁺ regulatory T cells (CD4⁺CD25⁺ Tr) and thymus CD4^-CD25⁺ cells. METHODS: The ratios of CD4⁺CD25⁺ regulatory T cells to CD4+ T cells in thymus, spleen, lymph node and peripheral blood of mice from birth to mature and also the ratios of CD4^-CD25⁺ cells to CD4^- T cells in thymus were measured by flow cytometry. Purified CD4⁺CD25⁺ T cells and CD4⁺CD25^- T cells were labeled with CFDA-SE, and then stimulated with various kinds of stimulators. RESULTS: The percentages of CD4⁺CD25⁺ Tr in mouse spleen, lymph nodes and peripheral blood increased gradually, but not in thymus, from day one to week 10 of the age with rapid rising from day one to week 1. The percentages of CD4^-CD25⁺ cells in mouse thymus were quite high on day one after birth, and decreased rapidly from day one to week 1. Both CD4⁺CD25⁺ Tr and CD4⁺CD25^- T cells showed no proliferation in response to ConA, while CD4⁺CD25⁺ Tr showed a transient enlargement of cell size. Both CD4⁺CD25⁺ Tr and CD4⁺CD25^- T cells underwent proliferation in response to PDB plus ionomycin. CD4⁺CD25^- T cells, but not CD4⁺CD25⁺ Tr, showed a proliferative response to the stimulation of coated anti-CD3 plus soluble anti-CD28 antibody, however, CD4⁺CD25⁺ Tr showed significant proliferation and CD4⁺CD25^- T cells showed a stronger response in addition of high dose of IL-2. CONCLUSION: The thymus CD4^-CD25⁺ cells are probably the precursor of CD4⁺CD25⁺ Tr during cell development.     

Elevation of blood Th17 cells and CD3+CD8-IL-21+ T cells in patients with cervical cancer

AIM: To investigate the role of Th17 cells in the patients with cervical cancer.METHODS: We measured the peripheral levels of Th17 cells and CD3⁺CD8^-IL-21⁺ T cells in 37 cervical cancer (CC) patients, 25 cervical intraepithelial neoplasia (CIN) patients and 18 healthy controls by flow cytometry. The percentages of Th17 cells and CD3⁺CD8^-IL-21⁺ T cells in total CD4⁺ cells were calculated.RESULTS: Compared with controls, the patients with CC or CIN had higher proportions of Th17 cells (all P<0.01) and CD3⁺CD8^-IL-21⁺ T cells (all P<0.05). Notably, in CC patients, the increased percentages of Th17 cells and CD3⁺CD8^-IL-21⁺ T cells were independently associated with the clinical stage(all P<0.05), lymph node metastasis (P<0.01,P<0.05) and vasoinvasion (all P<0.01), while the elevated percentage of CD3⁺CD8^-IL-21⁺ T cells was also associated with the tumor size(P<0.01). Furthermore, the percentage of Th17 cells was positively correlated with that of CD3⁺CD8^-IL-21⁺ T cells in healthy controls and CC patients, but not in CIN patients.CONCLUSION: Our results indicates a possible role of Th17 cells in CC patients correlated with CD3⁺CD8^-IL-21⁺T cells, and the elevated percentage of circulating Th17 cells may be involved in the development and progression of cervical cancer.     

Effects of magnesium on apoptosis and expression of Foxp3 in peripheral CD4+CD25+ regulatory T cells from asthma patients

AIM:To observe the apoptosis and the expression of forkhead box protein 3(Foxp3) induced by magnesium in CD4⁺CD25⁺ regulatory T cells isolated from healthy and asthmatic human peripheral blood. METHODS:Peripheral blood from healthy volunteers and asthma patients was collected. CD4⁺CD25⁺ T cells were separated by Percoll centrifugation and magnetic separation. The cells were cultured for 72 h and treated with magnesium(10 mmol/L) or control solution. The apoptotic rate and the expression of Foxp3 in the cells were analyzed by flow cytometry. RESULTS:The purity of CD4⁺CD25⁺T cells was 77.4%~92.3% in health group, and was 75.2％~93.8％in asthma group. The proportion of CD4⁺CD25⁺ T cells in CD4⁺T cells was 4.12%~7.98% in healthy adults, and 4.51%~8.68% in asthma patients. No significant difference between the 2 groups was observed. Magnesium at concentration of 10 mmol/L up-regulated the apoptotic rate of CD4⁺CD25⁺ T cells(P<0.05) and did not affect the Foxp3 expression in the cells in both health and asthma groups. CONCLUSION:Magnesium plays therapeutic effects on asthma by inducing the apoptosis of peripheral CD4⁺CD25⁺ regulatory T cells.     

Effects of thymosin α1 on the development and maturation of thymocytes

AIM: To investigate the effect of Thymosin α₁ on the development and matutation of thymocytes. METHODS: The proportion of CD4⁺CD8⁺ thymocytes and the expression of smoothened (Smo) of the hedgehog (Hh)-signaling in CD4^-CD8^-thymocytes were examined to observe the effect of thymosin α₁ on thymocyte development and matutation. RESULTS: Flowcytometric analysis showed that thymosin α₁ showed activity at a low dose of 30 μg/kg, and 30 μg/kg thymosin α₁ accelerated the replenishment and maturation of thymocytes according to the expression of Smo of the Hh-signaling in CD4^-CD8^-thymocytes, the potent negative regulator of proliferative responses. CONCLUSION: Thymosin α₁ can accelerates thymocyte development from CD4^-CD8^- to CD4⁺CD8⁺.     

Changes of CD28, CD56 and CD57 expression on CD8+T cells in the peripheral blood of healthy elderly individuals

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.     

Phenotype of decidual NK cells in women with hypertensive disorder complicating pregnancy

AIM: To investigate the phenotype of uterine decidual natural killer cells (dNK cells) in women with hypertensive disorder complicating pregnancy (HDCP). METHODS: All the study subjects were collected from Department of Obstetrics and Gynecology, The First Affiliated Hospital of Jinan University, Guangzhou, China. Twenty cases of singleton pregnancy who underwent caesarean section because of HDCP were selected as HDCP group, and 15 cases of singleton pregnancy received selective caesarean section because of social-psychological concerns were also randomly selected as normal control group. The decidual tissues were sampled immediately after caesarean section. The mononuclear cells were extracted from the tissues by means of mechanic grinding and gradient centrifugation. The technique of flow cytometry was used for dNK cell sorting and the expression of CD56 and CD16 on the surface of cells was also examined. RESULTS: In HDCP group and normal control group, the proportions of CD56^brightCD16^-CD3^- dNK cells were significantly higher than those of CD56^dimCD16⁺CD3^-dNK cells (P<0.01). Neither the CD56^brightCD16^-CD3^- subset nor the CD56^dimCD16⁺CD3^- subset had statistical difference between HDCP group and normal control group. No significant difference of CD16 expression on the surface of dNK cells between HDCP group and normal control group was observed (P>0.05). CONCLUSION: The phenotypes of dNK cells from the women with HDCP and from healthy pregnant women are both dominated by CD56^brightCD16^-CD3^- subset, without significant difference.     

The biological characteristics of cytokine-induced killer cells

AIM:To investigate the biological characteristics of cytokine-induced killer (CIK) cellsin vitro.METHODS:The non-adhere peripheral blood monoclear cells from healthy donors were induced into CIK cells in the presence of IFN-γ, IL-1β, IL-2 and anti-CD3 antibody. LAK (lymphokine activated killer) cells were prepared as a control. The cellular phenotype were detected by FCM and immunocytochemistry and the cytotoxicity was measured by LDH release assay.RESULTS:After 2 weeks of induction, the proliferation rate of CIK cells reached a peak and the proportion of CD3⁺ population was above 95%, and then the cells growth entered to plateau phase at week 3. The proportion of CD3⁺CD56⁺ NKT subset cells was 16.5% on day 15 and it had no obvious variety between 2 and 4 weeks. Correspondingly, LAK cells grew slowly and had lower proliferation rate compared with the CIK cells (P<0.01). CIK cells showed higher specific lysis rates to BeL-7402 hepatoma cells than those of LAK cells at different effector to target ratio (P<0.01). Immunocytochemical staining showed the CIK cells highly co-expressed HLA-DR and CD54 antigens. The NKT cells were slightly bigger than CD3⁺CD56^- cells and a large quantity of pseudopodia were observed on their surface.CONCLUSION:The CIK cells have higher proliferation potency and stronger cytotoxicity to lyse tumor cells than LAK cellsin vitro.Within the span of time from 14 to 21 days, the proliferation rate and the proportion of CD3⁺CD56⁺ subset of CIK cells all reach peaks. Therefore, CIK cells in this period are suitable for clinical application.     

Expression of EPCAM,CD44 and CD24 in gastric cancer tissues and its clinical significance

AIM: To evaluate the relationship between epithelial cell adhesion molecule (EPCAM)/cluster of differentiation 44 (CD44)/cluster of differentiation 24 (CD24) expression and the clinicopathological characteristics/prognosis in 95 gastric cancer patients. METHODS: The expression levels of EPCAM, CD44 and CD24 were detected using the two-step method of immunohistochemistry in 95 gastric cancer patients who underwent surgical excision and were pathologically diagnosed as gastric cancer. RESULTS: There were 56 EPCAM-positive patients (58.95%), 41 CD44-positive patients (43.16%) and 56 CD24-positive patients (58.95%). Thirty patients were both EPCAM and CD44 positive (31.58%), 45 patients were both EPCAM and CD24 positive (47.37%), 32 patients were both CD44 and CD24 positive (33.68%), and 25 patients were EPCAM, CD44 and CD24 positive (26.32%). EPCAM expression was correlated with age, depth of tumor infiltration and WHO histological classification. CD44 expression was correlated with BORRMANN and WHO histological classification as well as CEA value. CD24 expression was correlated with the depth of infiltration, location of the tumor, WHO histological classification and viscera invasion. All positive expression of EPCAM, CD44 and CD24 was correlated with the depth of infiltration, location of the tumor and WHO histological classification (P<0.05). The difference of survival rate between EPCAM positive group and negative group was observed, and the CD44 positive group and negative group had the same result (P<0.05 and P<0.01, respectively). The difference of survival rate between EPCAM⁺CD44⁺CD24⁺ group and EPCAM^-CD44^-CD24^- group was statistically significant (P<0.05). The difference of survival rate between EPCAM^-CD44⁺CD24⁺ group and EPCAM^-CD44^-CD24^- group was also significant (P<0.05). CONCLUSION: The positive rates of EPCAM, CD44 and CD24 expression are high in gastric cancer tissues and these 3 proteins can be used as primary screening targets.     

Establishment of method for PD-1 immunophenotype detection in TCR Vβ repertoire of CD3+, CD4+ and CD8+ T-cell subsets

AIM:To establish the method for detecting the immunophenotype of immunosuppressive receptor programmed cell death protein 1 (PD-1) in T-cell receptor (TCR) Vβ repertoire of CD3⁺, CD4⁺ and CD8⁺ T-cell subsets, therefore to evaluate the distribution of PD-1 in T-cell repertoire from human peripheral blood (PB). METHODS:The PB samples from 10 cases of healthy individuals (HI) were collected. Using multi-colored fluorescence flow cytometry, the distribution frequency of PD-1 in TCR Vβ repertoire was detected with a wide panel of anti-CD45, anti-CD3, anti-CD4, anti-CD8, anti-PD-1 and 24 anti-TCR Vβ repertoire (IOTest^® Beta Mark TCR Vβ Repertoire Kit, containing 8 tubes which labeled A~H, each tube is a composite antibody of FITC and PE coupling, each cocktail contains antibodies direc-ted to 3 different Vβ subfamilies) monoclonal antibodies. RESULTS:The total number of the 24 TCR Vβ repertoire detected in CD3⁺, CD3⁺CD4⁺ and CD3⁺CD8⁺ T cells from 10 cases of HI was consistent with the Quick Reference Card data provided by the kit. The preliminary results showed that the frequency of Vβ usage in CD3⁺, CD4⁺ and CD8⁺ T cells was different. High usage of Vβ2, Vβ3, Vβ8, Vβ9, Vβ5.1, Vβ13.1 and Vβ13.2 was found in CD3⁺ T cells, while high usage of Vβ2, Vβ3, Vβ8, Vβ5.1, Vβ9 and Vβ13.1 in CD3⁺CD4⁺ T cells, and high usage of Vβ1, Vβ2, Vβ3, Vβ9, Vβ13.1 and Vβ13.2 in CD3⁺CD8⁺ T cells were also observed. Further analysis showed that the expression of PD-1 was detected in all 24 TCR Vβ subfamilies of CD3⁺, CD3⁺CD4⁺ and CD3⁺CD8⁺ T cells. The higher frequency of PD-1⁺ T cells was CD4⁺Vβ5.2⁺ T cells, whereas the higher frequency of PD1⁺ T cells in CD8⁺Vβ11⁺ and CD8⁺Vβ13.6⁺ T cells was detected. CONCLUSION:The method for detection of the immunosuppressive receptor PD-1 in TCR Vβ repertoire of T-cell subsets is successfully established, which provides a new method for further analysis of immunosuppressive characteristics of TCR Vβ repertoire in the patients with leukemia.     

Proportion of CD14+CD16+ monocytes in peripheral blood from patients with type 2 diabetic mellitus and effect of LPS and IL-15 on expression of STAT5 in monocytes

AIM: To characterize the proportion of CD14⁺CD16⁺ monocytes in peripheral blood from type 2 diabetes (T2DM) patients and to observe the response of CD14⁺CD16⁺ monocytes to lipopolysaccharide (LPS) and interleukin-15 (IL-15) for further exploring the potential mechanism of inflammatory immune response in the pathogenesis of T2DM. METHODS: Twenty-eight patients with T2DM and 20 healthy volunteers were enrolled in the study. The peripheral blood was collected for determining the percentage of CD14⁺CD16⁺ monocytes by flow cytometry. The peripheral blood mononuclear cells (PBMC) were isolated and subject to stimulation with LPS and IL-15 for 4 h. The protein expression of STAT5 was detected by Western blotting and the phosphorylated (p)-STAT5 was determined by Western blotting and immunofluorescence. Serum levels of 25-hydroxyvitamin D₃ and IL-6, and the concentrations of IL-6 and monocyte chemoattractant protein-1(MCP-1) in the culture supernatants were assessed by ELISA. Serum level of C-reactive protein (CRP) was measured by immunoturbidimetry. RESULTS: There were positive correlations between the quantity of CD14⁺CD16⁺ monocytes and serum levels of CRP and IL-6 (r=0.394, P<0.05 and r=0.741, P<0.01), while serum 25 (OH) D₃ was negatively correlated with the quantity of CD14⁺CD16⁺ monocytes (r=-0.409, P<0.01), serum CRP(r=-0.479,P<0.01) and serum IL-6 (r=-0.774,P <0.01). After stimulated with LPS and IL-15, PBMC showed significant up-regulation of p-STAT5 protein expression, and significant increases in the supernatant levels of IL-6 and MCP-1 were observed (P<0.05). The expression of p-STAT5 existed in the nucleus.CONCLUSION: These findings suggest that the functional disturbance in monocytes occurs in T2DM, which may be related to insufficiency of vitamin D₃. The aberrant activation of STAT5 signaling pathway underlies the functional abnormalities of the monocytes in T2DM.     

Percentage change on natural killer subsets of peripheral blood and decidua in between normal early pregnancy and spontaneous abortion

AIM: To determinate the percentage change on natural killer(NK) subsets of peripheral blood and decidua in between normal early pregnancy and spontaneous abortion. METHODS: Flow cytometry was used to detect the expression of CD56 and CD16 on lymphocytes of decidua and peripheral blood in normal early pregnancy and spontaneous abortion. RESULTS: In peripheral blood, the percentage of CD56⁺ of spontaneous abortion tended to decrease in comparison with normal early pregnancy, and the percentage of CD56⁺CD16⁺ in spontaneous abortion was significantly less than that in normal early pregnancy. The percentages of different natural killer subsets in decidua of spontaneous abortion were significantly lower than those in decidua of normal early pregnancy. CONCLUSION: The decrease of CD56⁺NK cells in decidua may be one of causes for abortion, the loss of CD56⁺ and CD56⁺CD16^+NKcells in peripheral blood could have a diagnostic value for spontaneous abortion.     

CD4+CD25+FOXP3+ Tregs and HBV-specific CTLs in peripheral blood from chronic hepatitis B patients

AIM: To investigate the roles of CD4⁺CD25⁺FOXP3⁺ regulatory T cells (Tregs) and HBV-specific cytotoxic T-lymphocytes (CTLs) in peripheral blood from the patients with chronic hepatitis B (CHB).METHODS: Peripheral blood mononuclear cells from 28 patients with CHB and 15 healthy controls were analyzed for Treg frequency using flow cytometry and for HBV-specific CTLs using enzyme-linked immunospot assay (ELISPOT).The clinical data of HBV-infected patients were considered.RESULTS: The frequency of CD4⁺CD25⁺FOXP3⁺Tregs was higher in the patients with CHB than that in the patients of healthy controls (3.14%±0.97% vs 1.95%±0.68%, P<0.05), and a positive correlation was found between Tregs and the DNA levels of HBV (r=0.831, P<0.01).HBV-specific CTLs were detected by ELISPOT in CHB patients and a negative correlation was observed between Tregs and CTLs (r=-0.540, P<0.01).CONCLUSION: Peripheral blood CD4⁺CD25⁺FOXP3⁺ Tregs in CHB patients are increased and closely correlated with the DNA replication of HBV and CTLs, suggesting that the clearance of HBV can be influenced by the inhibition of cellular immunoreaction through Tregs.     

The effect of mifepristone on natural killer subsets of peripheral blood and decidua in early pregnancy

AIM: To investigate the effect of mifepristone on natural killer(NK) subpopulations of peripheral blood and decidua in early pregnancy. METHODS: Flow cytometry was used to detect the expression of CD56 and CD16 on lymphocytes of decidua and peripheral blood in early pregnancy, mifepristone-treated pregnancy. RESULTS: The percentages of different natural killer subsets in peripheral blood between early pregnancy and mifepristone-treated pregnancy were almost identical. The serum levels of estradiol and progesterone in mifepristone-treated pregnancy were slightly higher than in early pregnancy. The percentage of decidual CD56⁺NK cell in early pregnancy was significantly higher than in mifepristone-treated pregnancy. The CD56⁺NK cells were predominant lymphocyte population of decidua in mifepristone-treated pregnancy, but in which the CD56⁺CD16⁺ and CD16⁺NK cells were major lymphocyte subpopulations of peripheral blood. CONCLUSION: Mifepristone acted principally on feto-maternal interface, it blocked the proliferation and differentiation of decidual CD56⁺NK cells and induced embryo immune rejection.     

The ex vivo expansion characteristic of endothelial progenitor cells

AIM: To explore the ex vivo expansion characteristics of the endothelial progenitor cells (EPCs). METHODS: CD34⁺ cells were selected from umbilical cord blood mononuclear cells (MNC) by MiniMACS system, expanded at the same conditions as that for total MNC, coincubation of CD34⁺ and CD34^- from the same donation for EPCs. In addition, we tested the effect of vessel endothelial growth factor (VEGF) and passage on cell differentiation, expansion kinetics and apoptosis. EPCs were determined and quantified by immunocytochemistry and flow cytometry. RESULTS: Coculture of CD34⁺ and CD34^-,total MNC led to a significant increase in the expansion of CD34⁺ cells compared with CD34 enrichment (P＜0.05). There was a trend toward decreased apoptosis in cultures when early passage was performed once the linear cord like structures appeared. There was no significant effect on apoptosis between with VEGF and without VEGF group (P＞0.05). These differentiated EPCs were stained positive for CD34⁺, von Willebrand factor (vWF), KDR, CD31 and incorporate acetylated low-density lipoprotein (LDL). CD34⁺ and AC133⁺cells accounted for 68.2%±6.3% (n=6) and 57.2%±9.8% (n=6) of attaching (AT) cells at day 7 of culture, respectively. CONCLUSIONS: Coculture of CD34⁺ and CD34^- or culture of MNC enhances ex vivo expansion of EPCs. Early passage decreases apoptosis rate, VEGF has no significant effect on ex vivo expansion of EPCs.     

Relationship of CTCs with CD4+/CD8+, NLR,TTV and tumor stage in patients with primary hepatocellular carcinoma

AIM: To explore the relationship of circulating tumor cells (CTCs) with CD4⁺/CD8⁺, neutrophil-to-lymphocyte ratio (NLR), total tumor volume (TTV) and tumor stage in the patients with primary hepatocellular carcinoma.METHODS: We selected 80 cases of histologically diagnosed primary hepatocellular carcinoma in the study. The method of CanPatrol^TM was used, which was developed by SurExam biotechnology company to identify CTCs in the blood. CD4⁺ T cells and CD8⁺ T cells were counted by flow cytometry. The patients were divided into 2 groups according to the levels of CD4⁺/CD8⁺ ratio, NLR and TTV. The patients were also divided into Ⅰ＋ Ⅱstage group and Ⅲ＋ Ⅳ stage group according to the seventh edition of TMN staging criteria.RESULTS: The numbers of peripheral blood CTCs and mesenchymal CTCs in high CD4⁺/CD8⁺ ratio group were significantly lower than those in low CD4⁺/CD8⁺ ratio group (P < 0.05). The numbers of peripheral blood CTCs, mesenchymal CTCs and hybrid CTCs in high TTV group were significantly higher than those in low TTV group (P < 0.05). The numbers of peripheral blood CTCs, mesenchymal CTCs and hybrid CTCs in I＋ II stage group were significantly lower than those in III＋ IV stage group (P < 0.05). The numbers of peripheral blood CTCs, mesenchymal CTCs, hybrid CTCs and epithelial CTCs between high NLR group and low NLR group had no statistical difference.CONCLUSION: CTCs exist in the peripheral blood of the patients with primary hepatocellular carcinoma. The peripheral blood CTCs have significant correlations with TTV, tumor stage and T-cell immunity.The worse cell immune function, the larger TTV and the later tumor stage a patient has, the more the peripheral blood CTCs are.     

Identification and establishment of sorting method for isolating CD11b+ myeloid cells in human hepatic metastases from colorectal cancer

AIM: To establish a method for obtaining specific cells in solid tumor tissue by sorting of CD11b⁺ myeloid cells in hepatic metastases from colorectal cancer.METHODS: Tumor tissues were prepared into single cell suspension by mechanical method combined with enzyme digestion, and then the CD11b⁺ myeloid cells were isolated by flow cytometry. The sorted cells were identified by immunocytochemistry. The viability and morphologiy of the sorted cells were evaluated by Giemsa and Typan blue staining. The cell purity was evaluated by flow cytometry.RESULTS: Sufficient numbers of CD11b⁺ cells with high purity were isolated by sorting with flow cytometry from the single cell suspension prepared by mechanical and enzyme digestion. The purity of the cells was confirmed by statistical analysis (P<0.05). The positive rates of the cells before and after sorting were significantly different (P<0.01). The positive cells were verified by immunocytochemical method. Meanwhile, the sorted cells had complete morphology and good activity.CONCLUSION: The CD11b⁺ myeloid cells in solid tumor tissue can be isolated by flow cytometry from the machine-enzyme digestion suspension with high purity, good activity and complete morphology.     

Effects of Foxp3 transfection on splenocyte functions in asthma mice

AIM: To study the expression and the effects of Foxp3 on the immunologic functions by transfecting the Foxp3 eukaryotic expression plasmid into the splenocytes of the asthma mice. METHODS: The mice were sensitized and challenged by ovalbumin to make asthma model. The splenocytes were harvested and cultured. The Foxp3 expression vector pcDNA3.1(-)-Foxp3 was transfected into the splenocytes with electroporation. The splenocytes transfected with empty vector and control splenocytes (non-transfected) were also set up. The expression of Foxp3 at mRNA and protein levels was detected by RT-PCR and Western blotting, respectively. The proportion of CD4⁺CD25⁺ Treg cells/CD4⁺ cells was measured by flow cytometry. Proliferation of the splenocytes was analyzed with MTT assay. ELISA was used to determine the levels of interleukin 4 (IL-4) and interferon γ (IFN-γ) in the supernatant of the splenocytes. RESULTS: The expression of Foxp3 at mRNA and protein levels in transfection group was significantly higher than that in empty vector group and control group. The proportion of CD4⁺CD25⁺Treg cells/CD4⁺ cells in transfection group was higher than that in empty vector group and control group. The proliferation of transfected cells was markedly inhibited compared with empty vector group and control group. The levels of IL-4 and IFN-γ were significantly lower in transfection group than those in empty vector group and control group. CONCLUSION: The transfected Foxp3 gene overexpresses in the splenocytes of asthma mice. Foxp3 increases the number of CD4⁺CD25⁺ T cells and inhibits the proliferation and production of Th1/Th2 cytokines in splenocytes.     

Imperatorin increased sensitivity of lung cancer CD133+ cell subsets to gefitinib by down-regulating c-met expression

AIM: To investigate the role of imperatorin in reversing the resistance of the PC9 CD133⁺ cell subsets to gefitinib. METHODS: MTT assay was performed to evaluate the viability of PC9 cells treated with imperatorin and gefitinib. The expression of c-met, activation of caspases and phosphorylation of epidermal growth factor receptor (EGFR), PI3K and AKT in the PC9 cells treated with imperatorin and gefitinib were determined by Western blot. The percentage of CD133⁺ cell subsets population and the apoptotic rate of the PC9 cells treated with imperatorin and gefitinib were analyzed by flow cytometry. RESULTS: The sensitivity of the PC9 CD133⁺ cell subsets to gefitinib was significantly lower than that of the PC9 CD133^- cell subsets. Treatment with gefitinib alone significantly inhibited the protein levels of EGFR/PI3K/AKT in the PC9 CD133^- cell subsets but not the PC9 CD133⁺ cell subsets. Treatment with gefitinib alone increased the percentage of CD133⁺ cell subsets population in the PC9 cells. However, combination of gefitinib with imperatorin significantly inhibited the enrichment of CD133⁺ cell subsets population. Imperatorin down-regulated c-met expression, suggesting the c-met was the target of imperatorin in the PC9 CD133⁺ cell subsets. The results of MTT assay, Western blot analysis and flow cytometry indicated that imperatorin increased the gefitinib induced inhibition of PI3K/AKT protein levels by down-regulating the expression of c-met, which subsequently induced the cleavage of caspases and apoptosis in the PC9 CD133⁺ cell subsets.CONCLUSION: Imperatorin increases the sensitivity of lung cancer CD133⁺ cell subsets to gefitinib by down-regulating the expression of c-met, and the synergistic anti-tumor effect exists between imperatorin and gefitinib.     

Resveratrol enhances 5-fluorouracil-induced apoptosis of osteosarcoma CD133+ cell subset by promoting formation of Apaf-1/caspase-9 complex

AIM:To investigate the synergistic effect of resveratrol and 5-fluorouracil on osteosarcoma CD133⁺ cell subset.METHODS:Human osteosarcoma cell line MG-63 CD133⁺ cell subset and the corresponding CD133^- cell subset were treated with resveratrol and 5-fluorouracil.After treatment,the viability of MG-63 cells was measured by MTT assay.The apoptosis of MG-63 cells was analyzed by flow cytometry.Activation of caspase-9 and caspase-3,the expression of Apaf-1,and the release of cytochrome C were evaluated by Western blot.The interaction between Apaf-1 and pro-caspase-9 was detected by co-immunoprecipitation.RESULTS:The cell death and apoptosis of MG-63 CD133⁺ cell subset induced by 5-fluorouracil were significantly weaker than those in the corresponding MG-63 CD133^- cell subset.However,co-treatment with resveratrol significantly enhanced the effect of 5-fluorouracil on inhibiting the viability of MG-63 CD133⁺ cell subset.Mechanically,treatment with resveratrol upregulated the expression of Apaf-1.Transfection with Apaf-1 siRNA abolished the synergistic effect of resveratrol and 5-fluorouracil in MG-63 CD133⁺ cell subset.In addition,the results of co-immunoprecipitation indicated that the combination of resveratrol and 5-fluorouracil significantly induced the formation of Apaf-1/pro-caspase-9 complex,leading to the activation of caspase-9 in MG-63 CD133⁺ cell subset.CONCLUSION:Resveratrol enhances 5-fluorouracil-induced apoptosis of osteosarcoma CD133⁺ cell subset by promoting the formation of Apaf-1/caspase-9 complex.     

Effects of glucocorticoid on miRNA-155 expression in CD4+T cells of asthmatic mice

AIM:To investigate the effects of glucocorticoid on the regulation of microRNA-155 (miRNA-155) expression in the CD4⁺ T cells of asthmatic mice. METHODS:The ovalbumin (OVA)-induced asthma mouse model was established and the mice were treated with glucocorticoid. The effects of glucocorticoid on the pulmpnary histopathological changes, the expression of miRNA-155 in the lung tissues and CD4⁺T cells, and the levels of cytokines in the bronchoal-veolar lavage fluid (BALF) were evaluated. RESULTS:The results of RT-qPCR showed that the expressions of miRNA-155 in the lung tissues and CD4⁺T cells from the spleen of asthmatic mice were significantly increased, and the level of miRNA-155 in the CD4⁺T cells was significantly increased with the increase in the allergen exposure time (P<0.01). HE and PAS staining showed that OVA significantly increased inflammatory cell infiltration as compared with control group, and the peribronchial and perivascular inflammation and mucus secretion of proliferative goblet cells were significantly reduced after glucocorticoid treatment. Glucocorticoid treatment inhibited the increase in the proportion of CD4⁺ CD8^- cells in the spleen and decreased the accumulation of CD4⁺ T cells in the lung tissues of asthmatic mice (P<0.01). After glucocorticoid treatment, the levels of interleukin-4 (IL-4), IL-5 and IL-13 in BALF were decreased, while the level of interferon-γ was increased significantly (P<0.01). CONCLUSION:Glucocorticoid reduces the accumulation of CD4⁺ T cells and inhibits the expression of miRNA-155 in the lung tissues and spleen CD4⁺ T cells of asthmatic mice.