Atherosclerotic plaque rupture in the apolipoprotein E knockout mouse

The rupture of an atherosclerotic plaque is the main underlying cause of coronary artery thrombotic occlusion and subsequent myocardial infarction, but research into the causes and treatment of plaque rupture is hampered by the lack of a suitable animal model. Although complex atherosclerotic plaques can be induced in a number of experimental animal systems, in none of these is plaque rupture an established feature. We have surveyed branch points in the carotid arteries and aortas of apolipoprotein E knockout mice fed a diet supplemented with 21% lard and 0.15% cholesterol for up to 14 months. Six male and five female mice were used. Four of the male mice and four of the female mice died, after 46+/-3 weeks of feeding (range 37-59 weeks). Lumenal thrombus associated with atherosclerotic plaque rupture was observed in three male and all four female mice. In six of these seven mice, an atherosclerotic plaque rupture was found where the brachiocephalic artery branches into the right common carotid and right subclavian arteries. The ruptures were characterised by fragmentation and loss of elastin in the fibrous caps of relatively small and lipid-rich plaques overlying large complex lesions, with intraplaque haemorrhage. Immunocytochemical analysis revealed loss of smooth muscle cells from ruptured caps. These data suggest that long-term fat-feeding of apolipoprotein E knockout mice is a useful and reproducible model of atherosclerotic plaque rupture, and that these ruptures occur predominantly in the brachiocephalic artery.     

瑞舒伐他汀对载脂蛋白E基因敲除小鼠动脉粥样硬化的影响

目的 探讨瑞舒伐他汀对载脂蛋白E基因敲除(apoE-/-)小鼠主动脉粥样硬化的影响.方法 取apoE-/-小鼠18只建立动脉粥样硬化模型,C57BL/6小鼠12只为对照组.apoE-/-小鼠予高脂饲料,C57BL/6小鼠予普通饲料.12周后,随机抽取C57BL/6小鼠和apoE-/-小鼠各6只,判断是否成模.将成模后余下的12只apoE-/-小鼠随机分为模型组和瑞舒伐他汀治疗组(瑞舒伐他汀10 mg·kg-1·d-1灌胃),每组6只.余下的6只C57BL/6小鼠作为对照组.再过12周后处死小鼠,行血脂及主动脉HE、Masson、油红O染色观察动脉斑块,免疫组织化学方法检测主动脉组织平滑肌肌动蛋白(α-SMA)、转化生长因子β1(TGF-β1)、巨噬细胞表面分子-3(Mac-3)表达.结果 模型组小鼠胆固醇、低密度脂蛋白水平均高于对照组(P均＜0.01),甘油三酯水平与对照组比较差异无统计学意义.模型组小鼠主动脉组织内可见明显动脉粥样硬化斑块形成,α-SMA、TGF-β1和Mac-3表达均较高于对照组(P均＜0.01).瑞舒伐他汀治疗组小鼠胆固醇、低密度脂蛋白、甘油三酯水平与模型组比较差异无统计学意义,但斑块内脂肪含量少于模型组,胶原含量多于模型组.治疗组α-SMA表达与模型组比较差异无统计学意义,治疗组TGF-β1、Mac-3表达均低于较模型组(P均＜0.01).结论 瑞舒伐他汀可以减轻apoE-/-小鼠动脉粥样硬化模型中的脂质沉积和炎症反应,可以增加其胶原含量,利于斑块的稳定,具有抗动脉粥样硬化的作用,对血脂无影响.

Abstract：

Objective To investigate the effect of rosuvastatin on atherosclerosis in apoE-knockout ( apoE - / - ) mice. Methods Eighteen 6-week-old apoE - / - mice fed with high fat diet were used as atherosclerosis models, twelve 6-week-old C57BL/6 mice fed with normal diet were used as control. After twelve weeks, six apoE -/ - mice were used to observe the formation of atherosclerosis. Another 12 apoE -/- mice were divided into placebo treated group (n =6) and rosuvastatin group (n =6,10 mg· kg-1 ·d -1 per gavage) and treated for 12 weeks. Then, blood was collected for measuring lipid, aorta was prepared for morphologic study (HE, Oil red O, Masson) and immunohistochemical analysis (α-smooth activor protein, transforming growth factor β1, macrophage surface molecule-3 ). Results Serum cholesterol and low density lipoprotein levels were significantly higher in apoE -/- mice fed with high fat diet than in C57/ BL6 mice( all P ＜0. 01 )while triglyceride level was similar between the two groups, these were not affected by rosuvastatin. Similarly, atherosclerotic lesion area in apoE -/ - mice fed with high fat diet was also not significantly reduced by rosuvastatin, while lipid deposition could be significantly reduced and collagen deposition could be significantly increased in the aortic atherosclerotic lesions by treatment with rosuvastatin.Upregulated TGF-β1 and Mac-3 expression in the aortic atherosclerotic lesions in apoE -/- mice fed with high fat diet could also be significantly reduced by rosuvastatin (all P ＜ 0. 01 ), suggesting reduce inflammatory responses in the atherosclerotic lesion and stable atherosclerotic plaque post rosuvastatin treatment. Conclusion Reducing inflammatory responses and stabilizing plaque properties might contribute to the anti-atherosclerosis effects of rosuvastatin in mice high fat diet fed apoE -/- mice.     

Native incretins prevent the development of atherosclerotic lesions in apolipoprotein E knockout mice

Aims/hypothesis  

Several lines of evidence suggest that incretin-based therapies suppress the development of cardiovascular disease in type 2 diabetes. We investigated the possibility that glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) can prevent the development of atherosclerosis in Apoe ^−/− mice.     

Probucol prevents early coronary heart disease and death in the high-density lipoprotein receptor SR-BI/apolipoprotein E double knockout mouse

Mice with homozygous null mutations in the high-density lipoprotein receptor SR-BI (scavenger receptor class B, type I) and apolipoprotein E genes fed a low-fat diet exhibit a constellation of pathologies shared with human atherosclerotic coronary heart disease (CHD): hypercholesterolemia, occlusive coronary atherosclerosis, myocardial infarctions, cardiac dysfunction (heart enlargement, reduced systolic function and ejection fraction, and ECG abnormalities), and premature death (mean age 6 weeks). They also exhibit a block in RBC maturation and abnormally high plasma unesterified-to-total cholesterol ratio (0.8) with associated abnormal lipoprotein morphology (lamellar/vesicular and stacked discoidal particles reminiscent of those in lecithin/cholesterol acyltransferase deficiency and cholestasis). Treatment with the lipid-lowering, antiatherosclerosis, and antioxidation drug probucol extended life to as long as 60 weeks (mean 36 weeks), and at 5-6 weeks of age, virtually completely reversed the cardiac and most RBC pathologies and corrected the unesterified to total cholesterol ratio (0.3) and associated distinctive abnormal lipoprotein morphologies. Manipulation of the timing of administration and withdrawal of probucol could control the onset of death and suggested that critical pathological changes usually occurred in untreated double knockout mice between approximately 3 (weaning) and 5 weeks of age and that probucol delayed heart failure even after development of substantial CHD. The ability of probucol treatment to modulate pathophysiology in the double knockout mice enhances the potential of this murine system for analysis of the pathophysiology of CHD and preclinical testing of new approaches for the prevention and treatment of cardiovascular disease.     

Atheroprotective effect of adjuvants in apolipoprotein E knockout mice

Strategies aimed at treating atherosclerosis by immunization protocols are emerging. Such protocols commonly use adjuvants as non-specific stimulators of immune responses. However, adjuvants are known to modify various disease processes. The aim of this study was to determine whether adjuvants alter the development of atherosclerosis. We performed immunization protocols in apolipoprotein E knockout mice (E degrees ) following chronic administration schedules commonly employed in experimental atherosclerosis. Our results point out a dramatic effect of several adjuvants on the development of atherosclerosis; three of the four adjuvants tested reduced lesion size. The Alum adjuvant, which is the adjuvant currently used in most vaccination protocols in humans, displayed a strong atheroprotective effect. Mechanisms accounting for atheroprotective effect of Freund's adjuvants included their capacity to increase both Th2 responses and anti-MDA-LDL IgM titers, and/or to impose atheroprotective lipoprotein profiles. The present study indicates that adjuvants have potent atheromodulating capabilities, and thus, implies that the choice of adjuvant is crucial in long-term immunization protocols in experimental atherosclerosis.     

Hypertension and endothelial dysfunction in apolipoprotein E knockout mice

Mice lacking ApoE (Apoe(-/-)) develop initially hypercholesterolemia and lastly atherosclerosis. This study examined hemodynamics and endothelial function in 6-week-old Apoe(-/-) mice with hypercholesterolemia only, 7.5-months-old Apoe(-/-) mice with both hypercholesterolemia and atherosclerosis, and age matched controls. One day after implantation of catheters into the carotid artery, arterial pressure was measured in conscious, unrestrained mice. Compared with the respective controls, there was a significant increase in arterial pressure and the ratio of left ventricular weight to body weight in 7.5-month-old Apoe(-/-) mice but not in 6-week-old Apoe(-/-) mice. Histopathological analysis demonstrated significant renal artery disease in the form of extensive atheromatous plaques only in 7.5-month-old Apoe(-/-) mice, whereas no atherosclerotic lesions were found in 6-week-old Apoe(-/-) mice. For evaluation of endothelial function, a laser Doppler perfusion imager with a computer-controlled optical scanner was used to measure cutaneous blood perfusion on the dorsal side of one hind paw before and after topical application of mustard oil, which is known to induce nitric oxide-mediated vasodilation. The mustard oil treatment elicited a substantial increase in blood perfusion (P<0.01), which was similar between 6-week-old Apoe(-/-) mice and controls but significantly blunted in 7.5-month-old Apoe(-/-) mice versus control mice, suggesting nitric oxide-mediated vasodilation is diminished in 7.5-month-old Apoe(-/-) mice but not in 6-week-old Apoe(-/-) mice. In contrast, the increase in blood perfusion induced by topical administration of cilostazol, which induces vasodilation via cyclic adenosine monophosphate, was not different between 7.5-month-old Apoe(-/-) mice and controls. Thus hypertension and endothelial dysfunction observed in 7.5-month-old Apoe(-/-) mice may be due mainly to atherosclerosis.     

Dietary cholesterol suppresses the ability of olive oil to delay the development of atherosclerotic lesions in apolipoprotein E knockout mice

To test the hypothesis that cholesterol might suppress the beneficial effect of olive oil in atherosclerosis, we fed apoE KO mice diets containing extra virgin olive oil, either with or without cholesterol, for 10 weeks and assessed the development of atherosclerosis. Within each sex, mice were assigned randomly to one of the following four experimental groups: (1) a standard chow diet, (2) a chow diet supplemented with 0.1% cholesterol (w/w) cholesterol, (3) a chow diet enriched with 20% (w/w) extra virgin olive oil and (4) a chow diet containing 0.1% cholesterol and 20% extra virgin olive oil. On the standard chow diet, average plasma cholesterol levels were higher in males than in females. Olive oil- and cholesterol-enriched diets, separately or in combination, induced hypercholesterolemia in both sexes, and abolished the difference between the sexes in plasma cholesterol levels. The addition of cholesterol to chow or olive oil diets decreased apolipoprotein A-I significantly in females and serum paraoxonase activities in males. The latter activity was higher in females than in males. In both sexes, the size of aortic atherosclerotic lesions was similar in olive oil- and chow-fed animals and smaller than in cholesterol-supplemented groups. Size of aortic lesions were positively correlated with circulating paraoxonase activity, particularly in males, and the relationship remained after adjusting for apolipoprotein A-I and HDL cholesterol levels. Our results demonstrate that the nutritional regulation of paraoxonase is an important determinant of atherosclerotic lesions dependent on sex. They also suggest that the mere inclusion of olive oil in Western diets is insufficient and the adoption of Mediterranean diet would be more effective in retarding the development of atherosclerotic lesions.     

Hydrogen decreases athero-susceptibility in apolipoprotein B-containing lipoproteins and aorta of apolipoprotein E knockout mice

ObjectiveIt is to characterize the underlying molecular mechanisms of the anti-atherosclerotic effects of hydrogen (dihydrogen; H₂), a novel antioxidant. In particular, to examine the effects of hydrogen on athero-susceptibility in lipoproteins and aorta of apolipoprotein E knockout (apoE?/?) mice.Methods and resultsPlasma analysis by enzymatic method and spectrophotometric measurement showed that eight weeks intraperitoneally injection of hydrogen-saturated saline remarkably decreased plasma total and non-high-density lipoprotein (non-HDL) cholesterol, and malondialdehyde in apoE?/? mice fed either chow or high fat diet. Western blot analysis showed hydrogen treatment reduced the contents of apolipoprotein B (apoB), a major protein constituent of non-HDL in either plasma or hepatic tissues. Moreover, ELISA assay revealed that the production of tumor necrosis factor-α and interleukin-6 were significantly suppressed by hydrogen in RAW264.7 macrophages, after stimulation with the isolated non-HDL from treated or untreated mice. Immunohistochemistry of aortic valve sections revealed that hydrogen suppressed the expression of several proinflammatory factors and decreased vessel wall infiltration of macrophages. Besides, real-time PCR and Western blot analysis disclosed that hepatic scavenger receptor class B type I (SR-BI), ATP-binding cassette (ABC) transporters ABCG8, ABCB4, ABCB11, and macrophage SR-BI, were all induced by hydrogen treatment. Finally arterial wall lipid disposition displayed by oil red O staining was reduced significantly in aortic root and whole aorta en face in hydrogen administrated mice. In addition, hydrogen significantly improved HDL functionality in C57BL/6J mice assessed in two independent ways, namely (i) stimulation of cholesterol efflux from macrophage foam cells by measuring HDL-induced [³H]cholesterol efflux, and (ii) protection against LDL oxidation as a measure of Cu²⁺-induced TBARS formation.ConclusionThese results reveal that administration of hydrogen-saturated saline decreases athero-susceptibility in apoB-containing lipoprotein and aortic atherosclerosis in apoE?/? mice and improves HDL functionality in C57BL/6J mice.     

Activation of the Renin-Angiotensin system mediates the effects of dietary salt intake on atherogenesis in the apolipoprotein E knockout mouse

Dietary salt intake is a major determinant of the activation state of renin-angiotensin-aldosterone system. Given the important role of the renin-angiotensin-aldosterone system in plaque accumulation, we investigated its role in the development of atherogenesis associated with sodium intake in apolipoprotein E knockout mice. Six-weeks of a low-salt diet (containing 0.03% sodium) resulted in a 4-fold increase in plaque accumulation in apolipoprotein E knockout mice when compared with mice receiving normal chow (containing 0.30% sodium). This was associated with activation of the renin-angiotensin-aldosterone system, increased vascular expression of adhesion molecules and inflammatory cytokines, and increased adhesion of labeled leukocytes across the whole aorta on a dynamic flow assay. These changes were blocked with the angiotensin-converting enzyme inhibitor perindopril (2 mg/kg per day). A high-salt diet (containing 3% sodium) attenuated vascular inflammation and atherogenesis, associated with suppression of the renin-angiotensin-aldosterone system, although systolic blood pressure levels were modestly increased (5 ± 1 mmHg). Constitutive activation of the renin-angiotensin-aldosterone system in angiotensin-converting enzyme 2 apolipoprotein E knockout mice was also associated with increased atherosclerosis and vascular adhesion, and this was attenuated by a high-salt diet associated with suppression of the renin-angiotensin-aldosterone system. By contrast, a low-salt diet failed to further activate the renin-angiotensin-aldosterone system or to increase atherosclerosis in angiotensin-converting enzyme 2 apolipoprotein E knockout mice. Together, these data validate a relationship between salt-mediated renin-angiotensin-aldosterone system activation and atherogenesis, which may partly explain the inconclusive or paradoxical findings of recent observational studies, despite clear effects on blood pressure.     

Angiotensin II-induced TLR4 mediated abdominal aortic aneurysm in apolipoprotein E knockout mice is dependent on STAT3

Abdominal Aortic Aneurysm (AAA) is a major cause of mortality and morbidity in men over 65 years of age. Male apolipoprotein E knockout (ApoE^−/−) mice infused with angiotensin II (AngII) develop AAA. Although AngII stimulates both JAK/STAT and Toll-like receptor 4 (TLR4) signaling pathways, their involvement in AngII mediated AAA formation is unclear. Here we used the small molecule STAT3 inhibitor, S3I-201, the TLR4 inhibitor Eritoran and ApoE^−/−TLR4^−/− mice to evaluate the interaction between STAT3 and TLR4 signaling in AngII-induced AAA formation. ApoE^−/− mice infused for 28 days with AngII developed AAAs and increased STAT3 activation and TLR4 expression. Moreover, AngII increased macrophage infiltration and the ratio of M1 (pro-inflammatory)/M2 (healing) macrophages in aneurysmal tissue as early as 7–10 days after AngII infusion. STAT3 inhibition with S3I-201 decreased the incidence and severity of AngII-induced AAA formation and decreased MMP activity and the ratio of M1/M2 macrophages. Furthermore, AngII-mediated AAA formation, MMP secretion, STAT3 phosphorylation and the ratio of M1/M2 macrophages were markedly decreased in ApoE^−/−TLR4^−/− mice, and in Eritoran-treated ApoE^−/− mice. TLR4 and pSTAT3 levels were also increased in human aneurysmal tissue. These data support a role of pSTAT3 in TLR4 dependent AAA formation and possible therapeutic roles for TLR4 and/or STAT3 inhibition in AAA.     

高棕榈酸饮食对ApoE基因敲除小鼠动脉粥样硬化的影响

1目的：观察高棕榈酸饮食对载脂蛋白E（ApoE）基因敲除小鼠的血脂、血浆游离脂肪酸水平、动脉粥样硬化斑块面积、斑块中胶原含量和基质金属蛋白酶2表达的影响。方法：将20只6～8周龄雄性ApoE基因敲除小鼠随机分为对照组和高棕榈酸饮食组,每组10只。分别给予普通小鼠饲料和含5％棕榈酸的饮食,连续喂养12周。用比色法检测血脂和血浆游离脂肪酸水平;主动脉根部连续石蜡切片,Masson染色检测斑块内胶原含量,免疫组化法检测主动脉基质金属蛋白酶2的表达。结果：两组血脂水平无明显差异。与对照组相比,高棕榈酸饮食组血浆游离脂肪酸水平显著升高,主动脉斑块内胶原含量显著降低,主动脉基质金属蛋白酶2表达明显增加（P均〈0．05）。结论：高棕榈酸饮食能够升高血浆游离脂肪酸水平,降低斑块内胶原含量,从而降低动脉粥样硬化斑块稳定性,其机制可能与其上调基质金属蛋白酶2的表达有关。     

Introduction of human apolipoprotein E4 "domain interaction" into mouse apolipoprotein E

Human apolipoprotein E4 (apoE4) binds preferentially to lower density lipoproteins, including very low density lipoproteins, and is associated with increased risk of atherosclerosis and neurodegenerative disorders, including Alzheimer's disease. This binding preference is the result of the presence of Arg-112, which causes Arg-61 in the amino-terminal domain to interact with Glu-255 in the carboxyl-terminal domain. ApoE2 and apoE3, which have Cys-112, bind preferentially to high density lipoproteins (HDL) and do not display apoE4 domain interaction. Mouse apoE, like apoE4, contains the equivalent of Arg-112 and Glu-255, but lacks the critical Arg-61 equivalent (it contains Thr-61). Thus, mouse apoE does not display apoE4 domain interaction and, as a result, behaves like human apoE3, including preferential binding to HDL. To assess the potential role of apoE4 domain interaction in atherosclerosis and neurodegeneration, we sought to introduce apoE4 domain interaction into mouse apoE. Replacing Thr-61 in mouse apoE with arginine converted the binding preference from HDL to very low density lipoproteins in vitro, suggesting that apoE4 domain interaction could be introduced into mouse apoE in vivo. Using gene targeting in embryonic stem cells, we created mice expressing Arg-61 apoE. Heterozygous Arg-61/wild-type apoE mice displayed two phenotypes found in human apoE4/E3 heterozygotes: preferential binding to lower density lipoproteins and reduced abundance of Arg-61 apoE in the plasma, reflecting its more rapid catabolism. These findings demonstrate the successful introduction of apoE4 domain interaction into mouse apoE in vivo. The Arg-61 apoE mouse model will allow the effects of apoE4 domain interaction in lipoprotein metabolism, atherosclerosis, and neurodegeneration to be determined.     

Cystatin C deficiency increases elastic lamina degradation and aortic dilatation in apolipoprotein E-null mice

The pathogenesis of atherosclerosis and abdominal aortic aneurysm involves substantial proteolysis of the arterial extracellular matrix. The lysosomal cysteine proteases can exert potent elastolytic and collagenolytic activity. Human atherosclerotic plaques have increased cysteine protease content and decreased levels of the endogenous inhibitor cystatin C, suggesting an imbalance that would favor matrix degradation in the arterial wall. This study tested directly the hypothesis that impaired expression of cystatin C alters arterial structure. Cystatin C-deficient mice (Cyst C-/-) were crossbred with apolipoprotein E-deficient mice (ApoE-/-) to generate cystatin C and apolipoprotein E-double deficient mice (Cyst C-/-ApoE-/-). After 12 weeks on an atherogenic diet, cystatin C deficiency yielded significantly increased tunica media elastic lamina fragmentation, decreased medial size, and increased smooth muscle cell and collagen content in aortic lesions of ApoE-/- mice. Cyst C-/-ApoE-/- mice also showed dilated thoracic and abdominal aortae compared with control ApoE-/- mice, although atheroma lesion size, intimal macrophage accumulation, and lipid core size did not differ between these mice. These findings demonstrate directly the importance of cysteine protease/protease inhibitor balance in dysregulated arterial integrity and remodeling during experimental atherogenesis.     

鸢尾素对载脂蛋白E基因敲除小鼠动脉粥样硬化的影响

目的研究鸢尾素对载脂蛋白E基因敲除(ApoE~(-/-))小鼠动脉粥样硬化的影响。方法将ApoE~(-/-)小鼠随机分为正常对照组、动脉粥样硬化模型组、鸢尾素组,每组10只,分别给予普通饮食+生理盐水、高脂饮食+生理盐水、高脂饮食+鸢尾素,饲养至12周后处死,处死前测体重,用化学法测定总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDLC)、高密度脂蛋白胆固醇(HDLC)、血清超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量。采用HE染色和整体油红O染色分析主动脉粥样斑块面积大小,实时荧光定量(qRT-PCR)检测主动脉CD36、NF-κB p65的mRNA表达,Western blot检测主动脉CD36、NF-κB p65、SOD的蛋白表达。结果动脉粥样硬化模型组主动脉斑块面积明显高于正常对照组,内膜明显增厚,而鸢尾素组较动脉粥样硬化模型组斑块面积减少,内膜增厚程度下降。与正常对照组比较,动脉粥样硬化模型组小鼠体重、TC、TG、LDLC、MDA水平升高,NF-κB p65、CD36mRNA和蛋白表达增加,而血清SOD活性、HDLC水平减低(P0.05)。与动脉粥样硬化模型组比较,鸢尾素组小鼠体重、TC、TG、LDLC、MDA水平降低,NF-κB p65、CD36 mRNA和蛋白表达下调,而血清SOD活性、HDLC水平升高(P0.05)。结论鸢尾素能减轻ApoE~(-/-)小鼠动脉粥样硬化的发生发展,这可能与其降低小鼠体重和血脂、抑制炎症反应、抗氧化应激有关。     

Advanced atherosclerotic lesions in the innominate artery of the ApoE knockout mouse

Most previous studies of atherosclerosis in hyperlipidemic mouse models have focused their investigations on lesions within the aorta or aortic sinus in young animals. None of these studies has demonstrated clinically significant advanced lesions. We previously mapped the distribution of lesions throughout the arterial tree of apolipoprotein E knockout (apoE(-/-)) mice between the ages of 24 and 60 weeks. We found that the innominate artery, a small vessel connecting the aortic arch to the right subclavian and right carotid artery, exhibits a highly consistent rate of lesion progression and develops a narrowed vessel characterized by atrophic media and perivascular inflammation. The present study reports the characteristics of advanced lesions in the innominate artery of apoE(-/-) mice aged 42 to 60 weeks. In animals aged 42 to 54 weeks, there is a very high frequency of intraplaque hemorrhage and a fibrotic conversion of necrotic zones accompanied by loss of the fibrous cap. By 60 weeks of age, the lesions are characterized by the presence of collagen-rich fibrofatty nodules often flanked by lateral xanthomas. The processes underlying these changes in the innominate artery of older apoE(-/-) mice could well be a model for the critical processes leading to the breakdown and healing of the human atherosclerotic plaque.     

小鼠肠道粘膜固有层Lineage~-CD127~+淋巴细胞参与DSS诱导的早期急性结肠炎

目的对DSS诱导小鼠急性结肠炎早期分泌IL-17A和IL-22的主要淋巴细胞来源和分布情况进行初步探索。方法用3%DSS诱发C57BL/6J小鼠急性结肠炎;多色流式细胞术检测表面染色的淋巴细胞表面标记和胞内染色的IL-17A和IL-22的分泌情况。结果 DSS处理导致C57BL/6J小鼠肠道上皮内淋巴细胞所占比例下降,固有层淋巴细胞发生明显聚集。C57BL/6J小鼠肠道能产生IL-22和IL-17A的固有层Lineage+CD4+淋巴细胞所占的比例分别是:对照组为(0.26±0.08)%和(0.31±0.09)%,实验组为(0.29±0.08)%和(0.57±0.28)%,即固有层的Lineage+CD4+的淋巴细胞几乎不参与DSS诱导的早期急性结肠炎中IL-17A和IL-22的分泌。在DSS诱导的小鼠早期急性结肠炎中,分泌IL-22和IL-17A的固有层Lineage-CD127+淋巴细胞所占的比例分别是(45.13±2.39)%和(16.71±2.05)%,即肠道固有层Lineage-CD127+淋巴细胞是DSS诱导的小鼠早期急性结肠炎中IL-22和IL-17A的主要细胞来源之一。结论 DSS诱导的小鼠急性结肠炎早期IL-17A和IL-22的淋巴细胞来源之一是肠道固有层Lineage-CD127+淋巴细胞。