| Coronary heart disease (CHD) has become one of the greatest threat -ens to human beings since the 20th century. And its incidence increases gradurily when its causes and control methods has been the focus of social concern. The diagnosis and treatment of CHD is more and more, but its pathogenesis has not been very clear. Atherosclerosis (AS) is the main pathology of the cardiovascular disease. Lipid deposition, damage repair and thrombosis are the formation mechanism of AS. As we all know, heart disease, family history, gender, age, smoking, hypertension, diabetes and hyperlipidemia are the risk factors of AS. But we found that, the infection factors such as Chlamydia pneumoniae, Helicobacter pylori and cytomegalovirus aslo have great relationships with CHD. More and more studies show that acute coronary syndrome(ACS) is an important stage of progress of CHD, and the vulnerable plaque is the main pathology of ACS. Domestic and international study found that inflammation plays an important role in unstable plaque which is the main reason of causing plaque rupture. CHD is a chronic inflammatory and systemic autoimmune disease.The function of Dendritic cells (DCs) in the immune process is antigen presentation,which is the most powerful professional antigen-presenting cell. Very small amount of DCs can activate T lymphocytes to start strong immune response of specific cells. The domestic and international studys found that there is a vessel associated lymphoid tissue (VALT) in the intima where scattered with some immune cells and antigen-presenting cells, monitoring and screening the endogenous or exogenous antigens which may be harmful to the vascular tissue. We found that the numerber of DCs increased significantly in the AS lesions, DCs and T lymphocytes appear together in the weak position of AS. When the endogenous or exogenous antigens appear to DCs, the antigen can be presented to T cells which can activate and proliferate by DCs,and then secreting cytokines and starting a series of immune responses which leading to the development of AS. Recent studies have shown that oxidized low density lipoprotein(ox-LDL) can promote the progress of AS lesions through the acquired immune response activated by DCs.We found that ox-LDL is an endogenous immune response activator which can cause dysfunction of endothelial, involve in the formation of foam cells, promote proliferation of vascular smooth muscle cell and induce apoptosis. Previous studies showed that, ox-LDL which deposes localy in the AS, can promote adhesion between DCs and vascular endotheliar, stimulate the production of anti-oxidized low density lipoprotein antibody as a self-antigen, and promote differentiation and maturation of DC, activate T lymphocytes, and the leading the immune inflammation of local atherosclerotic lesions. Moderate ox-LDL can promote maturation of monocyte-derived DCs and enhance its function of activating T cell, increase IL-2, IL-12, IL-18, INF-y and TNFa secreted by DCs, and these effects are enhanced by the concentration and degree of oxidation of ox-LDL, but the too high concentration of ox-LDL will cause apoptosis of DCs.More and more researchs show that a variety of markers of inflammation involve in the occurrence, development and prognosis of CHD, such as IL-6, IL-10, IL-18, IL-12 and high sensitivity C reactive protein(hs-CRP). IL-27 is a newly discovered cytokines which composied by p28 and EBI3, belonging to IL-6/IL-12 family, which plays dual role in the immune response. The expression and functional changes of IL-27 were found in inflammatory, autoimmune, infectious, and neoplastic diseases because of its vital role of the regulation in immune response and tolerance. However, the study of IL-27 in CHD is very rare. We will explore the relationship between IL-27 and CHD by detecting the plasma level of IL-27 beweet different CHD patients.IL-27 is mainly produced by the activated DCs, monocytes, macrophages, NK cells, also can secrete a certain amount of IL-27. The secretion of IL-27 will happen when the the toll like receptors (TLRs) of DCs stimulating by the pathogen-associated molecular patterns (PAMP). DCs derived from human peripheral blood monocyte(PBMC) express receptor(heterodimer composed of EBI3 and p28) of IL-27, suggesting that IL-27 has an impact on DCs, which has a feedback on the DCs, promoting DCs to express costimulatory molecules and enhancing the activation of T helper cell (Th). Foreign researchers found that the DCs of WSX-1 knockout mice will increase the expression of surface molecules CD80/CD86 after stimulated by LPS in vitro, and then inducing proliferation of Thl cell and improving the production of IFN-γgreatly.DCs contacts the natural and acquired immune defense function, which is closely related to the development of CHD. Can IL-27 affect the function of immune by affecting DCs? How the functional status of DCs will be after the affection by IL-27? Will the function of proteins and secretion of immune regulatory molecules be affacted? This article aims to study the influence of IL-27 on immune activity of DC in vitro,to provide the basis mechanism for CHD.This article is divided into three parts, Part 1:the levels of IL-27 and high sensitivity C-reactive protein (hs-CRP) were detected by ELISA and immune turbidimetry of different types of CHD,which will be compared,with the purpose of investigating whether IL-27 is closely related to the stability of atherosclerotic plaque, and progress of coronary heart disease. Part 2: ox-LDL is used as an antigen to induce DCs maturation, the determination of subunits produced by DC by RT-PCR method, to explore the origin of IL-27. Part 3:ox-LDL is used as an antigen to induce DCs maturation, we observed the extent of DC maturation and secretion of cytokine by flow cytometry and ELISA, and further studies of application by IL-27 intervention. The article provide evidence of the immune mechanism for CHD by the combination of IL-27 and DCs by the influence on immune activity of DC,which provides experimental evidence of the development of AS-mediated immune. The results are summarized as follows:1 the levels of IL-27 and hs-CRP were significantly different among different CHD patients1.1 Comparison of the general clinical data among different groups showed no significant difference.88 cases were divided into as follow: control group (28 cases), SAP group (10 cases), UAP group (25 cases), AMI group (25 cases). Comparison of the general clinical data showed no significant difference among different group.1.2 Peripheral blood levels of IL-27 were significantly different among different CHD patients.Levels of IL-27 of CHD were more than the control group; Levels of IL-27 were the same between SAP group and UAP group; while the levels of IL-27 in SAP group and UAP group were higher than AMI group.1.3 Peripheral blood levels of hs-CRP were significantly different among different CHD patients.Levels of hs-CRP of CHD were more than the control group; Levels of hs-CRP of UAP group were more than the UAP group; while the levels of hs-CRP of AMI group were higher than SAP and UAP group.1.4 The relationship between IL-27 and hs-CRP of CHD.The correlation analysis showed that IL-27 and hs-CRP were positively correlated of 88 cases. 2 ox-LDL is used as an antigen to induce DCs maturation, the determination of subunits produced by DC is evaluate by RT-PCR methodThe test include 4 groups(n=3):(1) Control group:DC+PBS; (2) DC+ox-LDL(100mg/L,8h) group; (3) DC+ox-LDL(100mg/L,16h) group; (4) DC+ox-LDL(100mg/L,16h) group.2.1 Identification of DC by microscopeCell shapes under inverted phase contrast microscope and electron microscope are reported as fllowing:the cells shapes changed from round to irregular after induced by ox-LDL, some spinule-like structures newly erupted and the cytoplasm were getting thicker and thicher.2.2 The determination of subunits produced by DC is evaluate by RT-PCR methodOx-LDL increased the mRNA expression of IL-27 subunits(P28 and EBI3), the mRNA expressions of P28 and EBI3 of ox-LDL are higher than the control group, with the time-dependent characteristics.3 The roles of ox-LDL on DC maturation derived from PBMC immune and intervention by IL-27.The test includes 3 groups(n=3), atction for 24h:(1) Control group: DC+PBS;(2)DC+ox-LDL(100mg/L)group;(3)DC+ox-LDL(100mg/L)+IL-27(100ng/ ml)group.3.1 Identification of DC by microscope.Cell shapes under inverted phase contrast microscope and electron microscope are reported as fllowing:the cells shapes changed from round to irregular after induced by ox-LDL, some spinule-like structures newly erupted and the cytoplasm were getting thicker and thicher.3.2 Impact on the cell phenotypes, identified by flow cytometry.3.2.1 The upregulation of phenotypes expression on DC by ox-LDL. Phenotypes of DC derived from PBMC in peripheral blood were detected by flow cytometry. Phenotypes of DC including CD 83, CD86 and HLA-DR stimulated by ox-LDL are higher than the control group, indicating that ox-LDL can induce DC maturation which has a certain antigen-presenting function.3.2.2 IL-27 increase the expression of DC phenotypes induced by ox-LDL.The expression of DC phenotypes of CD83, CD86 and HLA-DR which post-treated by IL-27 were higher than that in ox-LDL group. This indicate IL-27 may promote the maturation by ox-LDL.3.3 Impact on levels of IL-6, IL-10 and IL-12p70 of DC stimulated by ox-LDL and IL-27.3.3.1 ox-LDL increase the levels of IL-6 and IL-10, decrease the levels of IL-12p70.After co-cultured DC stimulated by ox-LDL, the levels of IL-6 and IL-10 are higer than that in PBS group while the levels of IL-12p70 are lower. This indicate that ox-LDL may stimulate DC maturation, promote Thl secreteing IL-6, and have capability to promote Thl-type immune response.3.3.2 IL-27 increased the levels of IL-6 of DC stimulate by ox-LDL and decrease levels of IL-10.The levels of IL-6 of DC stimulated by ox-LDL which post-treated by IL-27 are higher than those of ox-LDL group while the levels of IL-10 are lower. This indicate that IL-27 may have the capability to promote Thl-type immune response and inhibit Th2-type immune response.The results are reported as follow:①The levels of IL-27 of different CHD patients were significantly higher than control group.This indicate that levels of IL-27 is associated with the disease which can be reference for assessment of CHD. ②Ox-LDL increased the mRNA expression of IL-27 subunits(P28 and EBI3). This indicate that ox-LDL can promote the secrection of IL-27 of DC derived from PBMC.③Ox-LDL can promote the maturation and differentiation of DC.④O-LDL can promote the maturation and differentiation of DC, and has the capability to promote the secretion of IL-6 by DC.⑤IL-27 may promote the maturation by ox-LDL and have the capability to promote the secretion of IL-6 by DC and inhibit the secretion of IL-10 by DC. |
PDF Full Text Request