IL-5 Up-regulates the Expression of TGF-β1 in Human Blood Eosinophils in Vitro

To investigate the effects of IL-5 on the expression of TGF-β1 in eosinophils in vitro, eosinophils were incubated in the presence of the same concentrations of IL-4, IL-5 and IFNγ, different concentrations of IL-5 in vitro and changes of eosinophil viability were assessed by trypan blue exclusion. Non-cytokine was employed as a negative control. 16 h after the cultivation, supernatants and cells were assayed by using TGF-β1 specific ELISA and RT-PCR. The mRNA expression and protein expresssion of TGF-β1 in eosinophils stimulated with different cytokines was observed.The expression of TGF-β1 protein in eosinophils was increased significantly by IL-4 (433.67±9.86vs 228.9±2.87) and IL-5 (403. 72±7.60 vs 228.9±2.87, P＜0.05), while decreased by IFNγ (178.47±2.60 vs 228.9±2.87). At the same time, the results demonstrated that the basal level of TGF expression was enhanced by IL5 in all samples (P＜0.05). The expression of TGF β1 mRNA was 1.42, 1. 70, 1. 76-folds higher than that of the non-stimulated controls. It is concluded that IL-5 can up-regulate the expression of TGF-β1 in eosinophils in vitro, which might have effect in eosinophil-associated chronic rejection.     

Inhibitory Effect of Dexamethasone on TGF-β1 Expression of Rabbit Ciliary Pigment Epithelia Cultured in Vitro

As is well-known,transforming growth fac-tor-beta1(TGF-β1)is a multi-functioning factorwith sti mulating or inhibitory effects to majority ofcells in the body.In ocular,many cell types ex-pressed TGF-β1andits receptors,such as cornea,lens,trabecular meshwork and retinal cells.Par-ticularly,TGF-β1has been believed to play a cru-cial roleinthe developing of eye embryo[1].Due tothe double-direction regulating effect to differentcell types,the exact mechanism and regulatorypattern are uncle…     

Modulation of Matrix Metalloproteinase and TIMP-1 Expression by TGF-β1 in Cultured Human RPE Cells

Matrix metalloproteinases(MMPs)are a familyof zinc binding,calcium-dependent endopeptidases thatfunction by degrading extracellular matrix(ECM)components.The functional effects of these enzymesare in part controlled byinteractions withtissueinhibi-tors of metalloproteinases(TI MPs)acting as naturalMMPinhibitors.Aprecise balance between MMPandTI MPactivities may be i mportant for the integrity ofECMcomponents[1].It shows that the expression andactivity of MMPs could be regulated by va…     

Effect of IL-Iβ and TNF-α on the expression of monocyte chemotactic protein-1 in endometriotic cells

Summary To investigate the clinical significance of monocyte chemotactic protein-1 (MCP-1) produced by endometriotic tissues, the endometriotic tissues were taken from 15 patients with endometriosis. MCP-1 mRNA and MCP-1 protein were determined by dot blot analysis and enzyme linked immunosorbent assay (ELISA) in endometriotic cells cultured with or without interleukin-1β (IL-lβ, 2 μg/L), tumor necrosis factor-α (TNF-α, 20 g/L). After exposure to IL-1β or TNF-α, the expression of MCP-1 mRNA in the endometriotic cells (8.635 ±0.826, 7.031 ±0.970, respectively) were significantly higher than that in the control group (4.482±0.435, P<0.05); The expression of MCP-1 protein in IL-lβ and TNF-α group was 4.52±0.09 μg/L,2.87±0.27 μg/L, respectively, which were significantly higher than 1.74±0.16 μg/L in control (P<0.01). The results suggested that IL-l\ and TNF-α could up-regulate the expression of MCP-1 in endometriotic cells, which might be related to the development of endometriosis.     

Effect of TGF-β1 on the expression of IL-12, IL-15, IL-18, IL-4 and IL-10 in heart transplantation rejection in rats

Summary To investigate the effect of TGF-β1 on the expressions of IL-12, IL-15, IL-18, IL-4 and IL-10 in heart transplantation rejection in rats, a model of rat cervical heterotopic heart transplantation was set up and the model rats were randomly divided into three groups: control group, transplant group and TGF-β1 group. The mRNA expression levels of IL-12, IL-15, IL-18, IL-4 and IL-10 were determined by RT-PCR at the 5th day after the transplantation. The mRNA expression levels of IL-12, IL-15, IL-18 were increased obviously and those of IL-4, IL-10 were significantly decreased in the transplant group as compared with the control group (P<0.01). In the TGF-β1 group, the mRNA expression levels of IL-12, IL-15, IL-18 were significantly decreased and those of IL-4, IL-10 were significantly increased as compared with the transplant group (P<0.01). The immunosuppressive effect of TGF-β1 on heart transplantation rejection was related to its inhibition of the expressions of Th1-type cytokines (IL-12, IL-15, IL-18 etc) and its promotion of the expressions of Th2-tpye cytokines (IL-4, IL-10).     

Changes of CD4^＋CD25^＋ Regulatory T Cells in Patients with Acute Coronary Syndrome and the Effects of Atorvastatin

The function of CD4＋CD25＋ regulatory T lymphocytes （Treg） in patients with acute coronary syndrome （ACS） and the effects of atorvastatin were investigated. Forty-eight patients with ACS were randomly divided into two groups： group C receiving conventional therapy （n=24）, and group C＋A receiving conventional therapy＋atorvastatin （10 mg/day, n=24）. T lymphocytes from ACS patients （before and 2 weeks after the treatment） or 18 healthy subjects were separated and the flow cytometry was used to measure the percentage of Treg. The inhibitory ability of Treg on effector T cells was determined by mixed lymphocyte reaction （MLR）. ELISA was used to measure the serum levels of cytokines （IL-10, TGF-β1 and IFN-γ） before and after treatment. The results showed that as compared with normal control group, Treg percentage was decreased significantly （P〈0.01）, the inhibitory ability of Treg on the T lymphocytes proliferation was reduced （P〈0.01）, IFN-γ levels were increased and IL-10 and TGF-β1 levels were lowered in ACS patients. After treatment with atorvastatin, Treg percentage and the inhibitory ability of Treg on T lymphocytes proliferation were significantly increased in ACS patients. Serum IFN-γ was decreased significantly, while IL-10 and TGF-β1 were elevated significantly as compared with the non-atorvastatin group. The number of Treg was positively correlated with serum TGF-β1, but negatively with serum IFN-γ and CRP. It was concluded that ACS was associated with decreased number and defected function of Treg, which may play an important role in initiating immune-inflammatory response in ACS. The inhibitory effects of atorvastatin on inflammation in ACS may be due to its beneficial effects on Treg and restoration of immune homeostasis.     

Th17 cells influence intestinal muscle contraction during <Emphasis Type="Italic">Trichinella spiralis</Emphasis> infection

Trichinella spiralis infection in rodents is a well-known model of intestinal inflammation associated with hypermotility. The aim of the study was to use this experimental model to elucidate if Thl 7 cells are involved in the development of gastrointestinal hypermotility. Colonic smooth muscle contractility was investigated in response to acetylcholine. The levels of IL-17, IL-23 and TGF-β1 in colon were measured by Western blotting. Flow cytometric detection of intracellular IFN-7/IL-4/ IL- 17 cytokine production was used to analyze the proportions of CD4＋ T cells subsets in colon. Our results showed that colonic muscle contractility was increased 2 weeks post infection （PI） and stayed high 12 weeks PI when no discernible inflammation was present in the gut. The proportion of Th17 cells and the expression of IL-17 were up-regulated in colon 2 weeks PI and returned to normal 8 weeks PI. The content of IL-17 was correlated with the colonic smooth muscle hypercontracility 2 weeks PI. Meanwhile, TGF-β1 was increased 2 weeks PI, while IL-23 was normal. Our results suggest that Th17 cells affect the colonic muscle contractility in mice infected with Trichinella spiralis at intestine stage but not at muscle stage and the effect of Th17 cells on muscle contractility might be induced by TGF-β1. Other cytokines might be involved in the hypercontracility of colonic smooth muscle at muscle stage.     

Effect of transforming growth factor-β2 on phagocytosis in cultured bovine trabecular meshwork cells

Summary The effect of transforming growth factor-β₂ (TGF-β₂) on phagocytosis in bovine trabecular meshwork cellsin vitro was investigated. After the cultured bovine trabecular meshwork cells were treated with 0 ng/ml, 0.32 ng/ml, 1 ng/ml, 3. 2 ng/ml TGF-β₂ for 24 h, latex beads were added into the incubation medium, and the numbers of the latex beads in 20 adjacent cells were counted under a microscope 24 h later, after treatment with Wright’s stain. Our results showed that the average numbers of the latex beads in the trabecular meshwork cells treated with TGF-β₂ of different concentrations were 53. 1±1. 7 beads/cell, 56. 4±2. 9 beads/cell and 77. 9±6. 5 beads/cell respectinvely, in comparison with 45. 5 ±3. 3 beads/cell of the control group. TGF-β₂ significantly increased the number of the latex beads phagocytosed by cultured bovine trabecular meshwork cells in a dose-dependent manner. TGF-β₂ could promote the phagocytosis of bovine trabecular meshwork cellsin vitro. It may be involved in the cellularity decrease of the trabecular meshwork in the patients of primary open angle glaucoma through promoting the phagocytosis of trabecular meshwork cells. This project was supported by a grant from the National Natural Science Foundation of China (No. 38970758).     

TGF-beta1 Transgenic Mouse Model of Thoracic Irradiation: Modulation of MMP-2 and MMP-9 in the Lung Tissue

TGF-β1has been shown to play a key role inthe development and progression of radiation-in-duced lung injury and subsequent fibrosis[1].Re-modeling of the lung is a hall mark of radiation-in-ducedlunginjury andinvolves extensive alterationsof lung extracellular matrix(ECM).MMPs are afamily of matrix degrading proteinases with struc-tural si milarities,and their activity is specificallyinhibited by the tissueinhibitors of metalloprotein-ases(TI MPs).In the present study,we intend toinvestig…     

Expression of transforming growth factor β<Subscript>1</Subscript> in mesenchymal stem cells: Potential utility in molecular tissue engineering for osteochondral repair

Summary The feasibility of using gene therapy to treat full-thickness articular cartilage defects was investigated with respect to the transfection and expression of exogenous transforming growth factor (TGF)-β₁ genes in bone marrow-derived mesenchymal stem cells (MSCs)in vitro. The full-length rat TGF-β₁ cDNA was transfected to MSCs mediated by lipofectamine and then selected with G418, a synthetic neomycin analog. The transient and stable expression of TGF-β₁ by MSCs was detected by using immunohistochemical staining. The lipofectamine-mediated gene therapy efficiently transfected MSCsin vitro with the TGF-β₁ gene causing a marked up-regulation in TGF-β₁ expression as compared with the vector-transfected control groups, and the increased expression persisted for at least 4 weeks after selected with G418. It was suggested that bone marrow-derived MSCs were susceptible toin vitro lipofectamine mediated TGF-β₁ gene transfer and that transgene expression persisted for at least 4 weeks. Having successfully combined the existing techniques of tissue engineering with the novel possibilities offered by modern gene transfer technology, an innovative concept, i.e. molecular tissue engineering, are put forward for the first time. As a new branch of tissue engineering, it represents both a new area and an important trend in research. Using this technique, we have a new powerful tool with which: (1) to modify the functional biology of articular tissue repair along defined pathways of growth and differentiation and (2) to affect a better repair of full-thickness articular cartilage defects that occur as a result of injury and osteoarthritis. GUO Xiaodong, male, born in 1970, Doctor in Charge