CC chemokine ligand 1 is released into the airways of atopic asthmatics.

CC chemokine ligand (CCL)1/I-309 is a potent attractant for T-helper cell type 2 lymphocytes. The present study investigates whether this cytokine is released in the bronchoalveolar fluid (BALF) of asthmatic patients. Measurements of CCL1 using ELISA showed that levels of this cytokine were significantly elevated in BALF from asthmatics compared with normals (median (range) 193 (120-449) pg.mL(-1) versus 30 (21-55) pg.mL(-1)). Differential cell counts in BALF showed that either lymphocyte or eosinophil numbers were elevated in asthmatic compared with normal subjects (10.8 x 10(3).mL(-1) versus 1.0 x 10(3).mL(-1) and 1.7 x 10(3).mL(-1) versus 0.2 x 10(3).mL(-1), respectively). There was a trend towards a significant correlation between CCL1 levels and lymphocyte numbers in BALF. Separation of BALF using sequential CCL1 affinity column and reverse-phase high-performance liquid chromatography allowed detection of biologically active CCL1. Using immunohistochemistry, CCL1 immunoreactivity was localised predominantly to the airway epithelium. Interestingly, there was a significant correlation between CC chemokine ligand 1 levels and epithelial cell numbers in bronchoalveolar lavage fluid and between these cells and lymphocyte numbers. Moreover, interleukin-4, interleukin-13 and interferon-gamma stimulated primary bronchial airway epithelial cells to release CC chemokine ligand 1. These findings suggest that CC chemokine ligand 1 may play a role in lymphocyte recruitment in bronchial asthma.     

The CC chemokine 6Ckine binds the CXC chemokine receptor CXCR3

We cloned the mouse homologue of the chemokine receptor CXCR3, which is located in mouse chromosome X. We screened a large panel of chemokines for their ability to induce a calcium flux in mouse CXCR3-transfected cells and identified a new ligand for this receptor, the recently reported CC chemokine 6Ckine. This represents an example of a CC chemokine, which binds to a CXC chemokine receptor. Like other ligands of this receptor, 6Ckine has angiostatic properties. 6Ckine is known to chemoattract T cells. In line with this, CXCR3 is expressed preferentially in Th1 cells and in lymphoid organs of the IL-10^−/− mouse that develops chronic colitis. Its ability to attract T cells as well as its angiostatic properties suggest that 6Ckine may be an effective anti-tumor agent.     

Genetic variations in CC chemokine receptors and hypertension

BACKGROUND: CC-chemokine receptor 5 (CCR5) is a co-receptor for human immunodeficiency virus type 1 (HIV-1) infection. Homozygosity for a 32-base pair (bp) deletion (Delta32) in the CCR5 gene confers resistance to HIV-1. Previous studies found an increased prevalence of hypertension among CCR5-Delta32 homozygotes and among carriers of a polymorphism (CCR2-64I) found on the gene that codes a closely related chemokine receptor. The present study was carried out to verify these associations. METHODS: Subjects in this cross-sectional study were selected from the Global Repository at Genomics Collaborative, which includes patients and healthy control subjects enrolled at multiple clinical sites in the United States and other nations. The current study includes 2842 subjects with hypertension and 2893 nonhypertensive control subjects from white populations in the United States and Poland. Case and control subjects were frequency matched by age, gender, and birthplace. All subjects were genotyped for CCR5-Delta32 and CCR2-64I polymorphisms by established Taqman assays. RESULTS: The CCR5-Delta32 genotype was not found to be associated with hypertension (CCR5-Delta32 heterozygosity: odds ratio [OR] 0.99, 95% confidence interval [CI] 0.87 to 1.14; CCR5-Delta32 homozygosity: OR 1.07, 95% CI 0.68 to 1.67) among these subjects. There was also no association between CCR2-64I genotype and hypertension (CCR2-64I heterozygosity: OR 0.96, 95% CI 0.83 to 1.10; CCR2-64I homozygosity: OR 1.18, 95% CI 0.73 to 1.92). These results changed little after adjustment for potential confounding variables. CONCLUSION: The results of the present study, which is much larger than previously published studies, provide no evidence that either CCR5-Delta32 or CCR2-64I is associated with hypertension.     

CC chemokine and CC chemokine receptor profiles in visceral and subcutaneous adipose tissue are altered in human obesity

BACKGROUND/AIMS: Obesity is associated with a low-grade inflammation, insulin resistance, and macrophage infiltration of adipose tissue. The role of CC chemokines and their respective receptors in human adipose tissue inflammation remains to be determined. METHODS: sc and visceral adipose tissue of obese patients (body mass index 53.1 +/- 11.3 kg/m(2)) compared with lean controls (body mass index 25.9 +/- 3.8 kg/m(2)) was analyzed for alterations in inflammatory gene expression. RESULTS: Macrophage infiltration was increased in sc and visceral adipose tissue of obese patients as determined by increased mRNA expression of a macrophage-specific marker (CD68) and by elevated macrophage infiltration. Gene expression of CC chemokines involved in monocyte chemotaxis (CCL2, CCL3, CCL5, CCL7, CCL8, and CCL11) and their receptors (CCR1, CCR2, CCR3, and CCR5) was higher in sc and visceral adipose tissue of obese patients. Serum concentrations of the inflammatory marker IL-6 and C-reactive protein were elevated in obese patients compared with lean controls. Obese patients revealed increased insulin resistance as assessed by the homeostasis model assessment of insulin resistance index and reduced plasma adiponectin concentrations. Adipose tissue expression of many CC chemokines and their receptors in the obese group positively correlated with CD68 expression. CONCLUSION: Up-regulation of the CC chemokines and their respective receptors in adipose tissue occurs in human obesity and is associated with increased systemic inflammation.     

CC chemokine receptor 5 influences late-stage atherosclerosis

Members of the chemokine system, play a central role in inflammatory processes that underlie the pathogenesis of atherosclerosis and possibly, aortic valve sclerosis. Here we show that genetic inactivation of CC chemokine receptor 5 (CCR5) in the atherosclerosis-prone Apoe-/- mice (Apoe-/- Ccr5-/-) fed a normal chow or a high-fat diet (HFD) are protected against advanced atherosclerosis as well as age-associated aortic valve thickening (AAAVT)--a murine correlate of aortic valve sclerosis. Notably, human sclerotic valves contained CCR5+ cells. We confirm that Apoe-/- Ccr5-/- mice does not influence early-atherosclerotic stage. Adoptive transfer studies showed that the atheroprotective effect of CCR5 inactivation resided in the bone marrow compartment, but was not dependent on T-cells. The CCR5-null state was associated with phenotypes postulated to be atheroprotective such as reduced macrophage accumulation in the plaque, and lower circulating levels of IL-6 and MCP-5. The lack of CCR5 expression in Apoe-/- mice was also associated with higher numbers of endothelial progenitor cells (EPCs)--another postulated athero-protective factor. Compared with controls, carriers of a polymorphism in the Ccr5 gene that leads to the lack of CCR5 in the cell surface had an increased mean percentage of EPCs, but this difference did not reach statistical significance. Collectively, these findings underscore a critical role of CCR5 in age-associated cardiovascular diseases, and highlight that the effects of the chemokine system can be temporally constrained to distinct stages of these disease processes.     

趋化因子受体CCR7在心血管疾病中的研究进展

心血管疾病可能由免疫炎症反应引起,而趋化因子及其受体在免疫炎症反应中起着关键的作用,提示其与心血管疾病的发生、发展密切相关。本文就趋化因子受体CCR7在动脉粥样硬化、心肌病、心力衰竭以及心脏移植排斥反应等疾病的发病过程中的作用做一综述。     

CC chemokine receptor 5 delta32 and CC chemokine receptor 2 64I polymorphisms do not influence the virologic and immunologic response to antiretroviral combination therapy in human immunodeficiency virus type 1-infected patients

To investigate the influence of the CC chemokine receptor 2 64I and CC chemokine receptor 5 delta32 polymorphisms on the virologic and immunologic response of human immunodeficiency virus type 1 (HIV-1)-infected patients to highly active antiretroviral therapy, data from 4 clinical studies were pooled. The prevalence of the CCR5 delta32 polymorphism was 21% (27 of 130 subjects), and the prevalence of the CCR2 64I polymorphism was 15% (19 of 130 subjects). There were no major differences between subjects with and without polymorphisms in the CCR5 and/or CCR2 genes with respect to the rate of initial viral clearance, proportion of subjects with plasma HIV-1 RNA levels below the lower limit of quantification, rate of virologic treatment failure, immunologic responses, and disease progression during 96 weeks of follow-up.     

The role of CC chemokine receptor 5 in antiviral immunity

The CC chemokine receptor CCR5 is an important coreceptor for human immunodeficiency virus (HIV), and there is a major thrust to develop anti-CCR5-based therapies for HIV-1. However, it is not known whether CCR5 is critical for a normal antiviral T-cell response. This study investigated the immune response to lymphocytic choriomeningitis virus in mice lacking CCR5 (CCR5(-/-) mice). This infection is a classical model for studying antiviral immunity, and influx of CCR5-expressing CD8(+) T cells and macrophages is essential for both virus control and associated immunopathology. Results showed that the virus-induced clonal expansion of antigen-specific T cells was augmented in CCR5(-/-) mice especially with regard to the CD4(+) subset. Despite absence of CCR5, intracerebral infection invariably resulted in lethal T cell-mediated meningitis, and quantitative and qualitative analysis of the inflammatory exudate cells did not reveal any significant differences between gene-targeted mice and wild-type controls. CCR5 was also found to be redundant regarding the ability to eliminate virus from internal organs. Using delayed-type hypersensitivity to evaluate CD8(+) T cell-mediated inflammation, no significant influence of CCR5 was found, not even when viral peptide was used as local trigger instead of live virus. Finally, long-term CD8(+) T cell-mediated immune surveillance was efficiently sustained in CCR5(-/-) mice. Taken together, these results indicate that expression of CCR5 is not critical for T cell-mediated antiviral immunity, and this molecule may therefore constitute a logic and safe target for anti-HIV therapies.     

趋化因子CCL20及其受体CCR6在急性坏死性胰腺炎中的表达及意义

目的 探讨CC趋化因子配体20(CCL20)和CC趋化因子受体6(CCR6)在实验性急性坏死性胰腺炎(ANP)发病机制中的作用.方法 48只SD大鼠按完全随机法分为ANP组和对照组.采用胆胰管逆行注射4%牛磺胆酸钠建立大鼠ANP模型,以注射等容积生理盐水作为对照组.术后1、3、6、12 h分批处死大鼠,取血检测血清淀粉酶,胰腺组织常规病理检查并评分,免疫组化和RT-PCR检测胰腺组织中CCL20、CCR6 mRNA及蛋白表达.结果 ANP大鼠血清淀粉酶和胰腺组织病理评分明显高于对照组.ANP组术后胰腺组织CCL20 mRNA及蛋白表达呈时间依赖性增强(P＜0.05);术后6 h胰腺组织中CCR6 mRNA明显高于对照组(0.88±0.05对0.23±0.09,P＜0.01),术后12 h CCR6mRNA表达较6 h时降低,但仍高于对照组(0.37±0.10对0.15±0.07,P＜0.05),CCR6蛋白变化与其mRNA变化一致.结论CCL20和CCR6参与ANP的发生和发展.     

支气管哮喘β2-肾上腺素受体基因多态性研究

目的探讨β2-肾上腺素能受体(β2-AR)16、27位点基因多态性与支气管哮喘的相关性。方法对2004年7月至2005年9月内蒙古医学院附属医院收治的42例支气管哮喘患者和30名健康者采用等位基因特异性聚合酶链反应(AS-PCR)和两对相对引物PCR法(confronting two-pair primers,PCR-CTPP)进行β2-AR基因多态性分析。结果(1)β2-AR16、27位点基因多态性分布频率与国内某些报道一致,与报道的英美高加索人群不同。(2)哮喘组人群β2-AR基因16位点多态性分布频率显示,精氨酸/精氨酸(Arg/Arg)基因型占14·2%,精氨酸/甘氨酸(Arg/Gly)基因型占80·9%,甘氨酸/甘氨酸(Gly/Gly)基因型占4·0%与健康组比较差异无显著性意义(P>0·05)。等位基因频率与健康组比较差异无显著性意义(P>0·05)。27位点多态性分布频率显示,谷氨酰胺/谷氨酰胺(Gln/Gln)基因型占76·2%,谷氨酰胺/谷氨酸(Gln/Glu)基因型占14·3%,谷氨酸/谷氨酸(Glu/Glu)基因型占9·5%与健康组比较差异无显著性意义(P>0·05)。等位基因频率与健康组比较差异无显著性意义(P>0·05)。结论β2-AR16、27位点基因多态性与哮喘未能证实存在相关性。     

Regulation of CC chemokine receptor 5 in hepatitis G virus infection

INTRODUCTION: Epidemiological data demonstrate an association between hepatitis G virus (HGV) co-infection and improved survival of HIV-positive individuals. However, the mechanism by which HGV affects progression of HIV disease remains unclear. As down-regulation of CC chemokine receptor 5 (CCR5) delays HIV progression, we investigated whether CCR5 expression is altered by exposure of lymphocytes to HGV proteins. METHODS: A cross-sectional analysis of CCR5 expression was carried out on CD4 and CD8 T lymphocytes of 11 HGV-positive and 12 HGV-negative persons, who were homozygous for the CCR5 wild-type gene. Binding of the HGV E2 protein to CD81 was analysed by flow cytometry. Lymphocytes were stimulated with immobilized HGV E2, anti-CD81 or serum proteins from HGV-infected subjects and changes in CCR5 expression and CC chemokine secretion were determined. RESULTS: We demonstrate that the HGV envelope protein E2 specifically binds to CD81 on T lymphocytes. This interaction induces a dose-dependent release of RANTES and down-regulation of CCR5 surface expression with concomitant intra-cellular accumulation of CCR5 proteins. This effect of HGV E2 on CCR5 expression was confirmed when lymphocytes were incubated with serum proteins from HGV-infected subjects. Finally, our cross-sectional analysis revealed CCR5 expression to be reduced by 53% and 36% on CD4 and CD8 lymphocytes of HGV-infected subjects, respectively (P < 0.01). CONCLUSIONS: Our results demonstrate that an interaction of HGV E2 with CD81 leads to increased RANTES secretion and decreased CCR5 surface expression. This mechanism might contribute to the delayed progression of HIV-infection in HGV-coinfected patients.     

Malaria enhances expression of CC chemokine receptor 5 on placental macrophages

Malaria and human immunodeficiency virus (HIV) coinfections are common in pregnant women in sub-Saharan Africa. The current study shows that placentas of malaria-infected women contain 3 times as much CC chemokine receptor 5 (CCR5) RNA as placentas of women without malaria. By immunohistochemistry, CCR5(+) maternal macrophages were seen in placentas from malaria-infected women but not in placentas from malaria-uninfected women. In addition, CCR5 also was found on fetal Hofbauer cells in placentas from both groups. Thus, malaria infections increase the potential reservoir for HIV in the placenta by increasing the number of HIV target cells.     

CC chemokine receptor 5 polymorphism in Italian patients with giant cell arteritis

Abstract

The involvement of valgus hindfoot deformity in hallux valgus deformity was confirmed in a rheumatoid arthritis case with a destructive valgus hindfoot deformity. Correction of severe valgus, calcaneal lateral offset, and pronated foot deformity instantly normalized hallux valgus deformities postoperatively. Thus, careful hindfoot status evaluation is important when assessing forefoot deformity, including hallux valgus, in rheumatoid arthritis cases.     

Monocyte chemoattractant protein-2 (CC chemokine ligand 8) inhibits replication of human immunodeficiency virus type 1 via CC chemokine receptor 5

CC chemokine receptor 5 (CCR5) is a coreceptor for cellular entry of monocyte-tropic (R5) strains of human immunodeficiency virus (HIV) type 1, which has been implicated as the predominant phenotype of HIV in early infection. The CCR5 agonists macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, and RANTES (regulated on activation, normally T cell-expressed and -secreted) have been shown to block replication of R5 virus in vitro and have gained attention as potential antiviral factors. However, a few reports have suggested that other chemokines may also block R5 HIV-1, including monocyte chemoattractant protein (MCP)-2 (CC chemokine ligand 8). We demonstrate that MCP-2 specifically inhibits replication of R5 HIV-1 and that this activity is additive to that of RANTES. Furthermore, MCP-2 induces a robust, pertussis toxin-sensitive calcium flux in primary lymphocytes, and cross-desensitization studies indicate that MCP-2 acts via CCR5. These data confirm that MCP-2 is a ligand for CCR5 on CD4(+) lymphocytes and can specifically block R5 HIV-1.     

Absence of the association with CC chemokine receptor 5 polymorphism in polymyalgia rheumatica

OBJECTIVE: Elevated RANTES serum levels are present in polymyalgia rheumatica (PMR) patients with active disease. Chemokines may contribute to the inflammatory PMR process through their binding to CC chemokine receptor 5 (CCR5). The aim of this study was to examine if the 32 base pair deletion allele in CCR5 (CCR5 delta 32 allele) might be associated with PMR susceptibility and influence the disease outcome. METHODS: We enrolled 88 consecutive patients with PMR residing in the Reggio Emilia area (Italy) who had a follow-up duration of at least one year. As a control group we used 86 healthy blood donors from the same geographic area. The CCR5 genotype of all PMR patients and controls was studied by polymerase chain reaction amplification of the region which includes the 32 deletion (CCR5 delta 32). RANTES serum levels were measured by commercial ELISA kits in CCR5 delta 32 heterozygous and CCR5 homozygous PMR patients at diagnosis before starting corticosteroid therapy and again after 6 months of therapy, as well as in 28 healthy subjects over 50 years of age. RESULTS: Frequencies of the CCR5 and CCR5 delta 32 alleles in patients and controls did not differ significantly. Homozygosity for CCR5 delta 32 was not detected in PMR patients and was detected in only one of the controls. No significant differences were observed between the patients carrying the CCR5 delta 32 allele and those homozygous for the normal CCR5 allele when we compared sex, presence of distal synovitis and systemic signs and/or symptoms, initial and cumulative prednisone dose, duration of therapy, ESR at diagnosis, frequency of relapse/recurrence and RANTES serum levels at diagnosis and after 6 months of corticosteroids. CONCLUSION: These results indicate that the frequency of the 32 deletion of the CCR5 receptor was not significantly different between PMR patients and healthy controls, and this genotype does not appear to be associated with the susceptibility to or severity of PMR.     

Expression of human immunodeficiency virus coreceptors CXC chemokine receptor 4 and CC chemokine receptor 5 on monocytes is down-regulated during human endotoxemia

Lipopolysaccharide (LPS) can inhibit human immunodeficiency virus (HIV) infection in monocytes in vitro. To test the hypothesis that an LPS effect on CXC chemokine receptor 4 (CXCR4) and CC chemokine receptor 5 (CCR5), known coreceptors for HIV, contributes to this effect, 8 healthy men were intravenously injected with Escherichia coli LPS (4 ng/kg), and monocyte CXCR4 and CCR5 expression was monitored by fluorescence-activated cell sorter analysis. LPS induced a decrease in the fraction of peripheral blood monocytes expressing CXCR4 and CCR5, reaching a nadir after 2 h (both P<.001 vs. baseline). In whole blood in vitro, not only LPS but also lipoarabinomannan (a cell wall component of Mycobacterium tuberculosis) and lipoteichoic acid (a cell wall component of Staphylococcus aureus) down-regulated the expression of CXCR4 and CCR5 on monocytes (all P<.05). Exposure of monocytes to (myco)bacterial agents may render them relatively resistant to infection with HIV by an effect on HIV coreceptors.