Increased CD40 ligand and platelet-monocyte aggregates in patients with type 1 diabetes mellitus

BACKGROUND: Diabetes mellitus is a major risk factor for cardiovascular disease and is associated with a proinflammatory and prothrombotic state. We investigated whether CD40 ligand (L) expression and platelet-monocyte aggregation are increased in patients with type 1 diabetes. METHODS: Serum C-reactive protein (CRP) and soluble (s) CD40L concentrations, platelet surface CD40L expression and platelet-monocyte aggregates were measured in 22 patients with uncomplicated type 1 diabetes and 22 age- and sex-matched non-diabetic control subjects. RESULTS: In comparison to controls, patients with type 1 diabetes had higher serum CRP concentrations (3.29 +/- 0.9 mg/L versus 0.99 +/- 0.2mg/L, P = 0.01), serum sCD40L concentrations (10.0 +/- 1.4 ng/mL versus 4.6 +/- 0.6 ng/mL, P = 0.006), and platelet surface expression of CD40L (13.8 +/- 0.9% versus 8.5 +/- 1.1%, P < 0.001). Platelet-monocyte aggregates were also significantly elevated in type 1 diabetes (35.9 +/- 3.3% versus 26.4 +/- 2.9%, P = 0.005; n = 10). We also observed a significant correlation between plasma glucose and serum CRP (r = 0.53, P = 0.01) as well as platelet-monocyte aggregates (r = 0.69, P = 0.03). CONCLUSIONS: Type 1 diabetes is associated with increased CD40L expression and platelet-monocyte aggregation, which may contribute to the proinflammatory and prothrombotic state as well as the accelerated atherogenesis associated with this disorder.     

Coexpression of CD40 and CD40 ligand in B-cell lymphoma cells

CD40 ligand (CD40L) is involved in the T-cell-dependent regulation of B-cell growth and survival and can rescue normal germinal centre B cells and several types of malignant B cells from apoptosis in vitro . We have previously reported that serum of patients with chronic lymphocytic leukaemia contained elevated levels of biologically active soluble CD40L (sCD40L). Whether an augmented CD40L pathway exists in patients with other types of B-cell lymphoid malignancies and the source of native sCD40L in these patients is currently unknown. Using a sensitive ELISA assay, soluble CD40L (sCD40L) was detected in the sera of both healthy individuals and patients with haematological malignancies; however, its level was significantly elevated only in patients with B-cell lymphomas ( P   < 0.0001). Several types of malignant B cells coexpressed CD40 and CD40L proteins, and CD40L mRNA was detected in purified resting malignant B cells. The dual expression of CD40 and CD40L in B cells and the presence of native sCD40L in human serum suggest that a direct T–B-cell contact may not be required for CD40L delivery to B cells. This data raises the possibility that an autocrine cytokine loop involving CD40L may contribute to the growth regulation of benign and malignant B cells in vivo .     

Upregulation of CD40/CD40L system in rheumatic mitral stenosis with or without atrial fibrillation

Thrombelastography (TEG) analyses the status of blood coagulation including abnormalities associated with low platelet count. The aim of this study was to investigate the changes in TEG parameters in idiopathic thrombocytopenic purpura (ITP) patients. Thirty nine patients with ITP (platelet count?<?100?×?103 µl^?1) were included in the study. Age-matched 17 patients with thrombocytopenia due to chemotherapy were selected as a control group. Platelet count was positively correlated with maximum clot formation (MCF) in INTEM (r?=?0.716, p?<?0.001) and MCF in EXTEM (r?=?0.679, p?<?0.001); negatively correlated with clot formation time (CFT) in INTEM (r?=??0.755, p?<?0.001) and CFT in EXTEM (r?=??0.585, p?<?0.001) in ITP patients. Platelet count was positively correlated with MCF in INTEM (r?=?0.776, p?<?0.001) and MCF in EXTEM (r?=?0.878, p?<?0.001); negatively correlated with CFT in INTEM (r?=??0.627, p?<?0.001) in control group. Receiver operating characteristic curves to describe the critical platelet count and fibrinogen level that affect MCF revealed 31?×?103?µl^?1 and 375 mg?dl^?1 as cut-off values, respectively. In conclusion, ROTEM determines the contribution of fibrinogen and platelets to clot strength in patients with ITP. MCF appears to be the most important TEG parameter in predicting bleeding in ITP patients that makes TEG superior to other hemostatic tests.     

CD40 and its ligand in atherosclerosis

CD40-CD40 ligand (CD40L) interactions play a central role in the development and progression of atherosclerosis. In the late 1990s, we and others have shown that complete inhibition of the CD40L signaling pathway resulted in a decrease in atherosclerosis and in the induction of a stable atherosclerotic plaque phenotype. These stable plaques contained high amounts of collagen and vascular smooth muscle cells, whereas the amount of macrophages and T lymphocytes was low. Because clinical complications of atherosclerosis are mostly the result of plaque rupture, induction of plaque stability would significantly reduce the morbidity and mortality of atherosclerosis and thus validates inhibition of the CD40L system as a therapeutic target for atherosclerosis. However, long-term inhibition of this system probably compromises the immune system of the patient. Therefore, it is desirable to target either the downstream signaling modulators of the CD40-CD40L system that are associated with atherosclerosis, or target the CD40-CD40L system in a local, cell type-specific way. This is likely to induce plaque stabilization with limited systemic side effects, and a significant reduction of cardiovascular disease.     

The CD40/CD40 ligand system in the skin of patients with subacute cutaneous lupus erythematosus

OBJECTIVE: To investigate whether CD40 and CD40 ligand (CD40L) is expressed in the skin of patients with subacute cutaneous lupus erythematosus (SCLE). METHODS: Six female patients with SCLE were studied. Skin biopsies were obtained from lesional and healthy sunprotected skin. Frozen sections were stained immunohistochemically using monoclonal antibodies to CD4, CD40, and CD40L. As controls we used 5 patients with discoid LE (DLE), 5 with dermatomyositis (DM), 3 with lichen planus (LP), and 2 with erythema multiforme (EM), as well as the normal-appearing skin of 5 healthy volunteers. RESULTS: The CD40 was intensely expressed in all SCLE, DLE, and DM lesions, and only focally in healthy sunprotected skin specimens. The number of CD40+ cells in SCLE dermis was lower than in DLE, similar to that in DM, LP and EM, and higher than in SCLE sunprotected skin. CD40L+ cells infiltrated the SCLE, DLE, DM, LP, and EM lesional dermis, and were more numerous in SCLE lesional skin than in SCLE healthy sunprotected skin. CONCLUSION: We showed that the CD40/CD40L system may represent an important pathway of induction of SCLE lesions. The expression of such costimulatory system in healthy sunprotected skin also may signify that its abnormal activation is constitutive in SCLE, as previously observed in systemic LE.     

Plasma concentrations of soluble CD40 ligand in smokers with acute myocardial infarction: a pilot study

Coronary artery disease (CAD) is believed to be the single leading cause of death in both men and women in the world. Smoking is the most important risk factor for CAD. Smoking increases platelet aggregation and thrombus formation. CD40 ligand (CD40L) is a transmembrane glycoprotein derived from activated platelets. It participates in thrombus formation during the acute phase of acute myocardial infarction (MI). Elevation of CD40L identifies the patients who are at highest risk for cardiac events and who are likely to benefit from treatment with the glycoprotein IIb/IIIa (GPIIb/IIIa) receptor antagonists. The purpose of this study was to evaluate levels of CD40L in smokers with acute MI. Fifty-seven patients with acute MI were enrolled in this study. Thirty-one smokers were compared with 26 non-smokers. Soluble CD40L level in the plasma was determined by a standard enzyme-linked immunosorbent assay. Circulating levels of CD40L were higher in the smokers’ group. Smokers with acute MI may have increased risk for thrombotic complications during acute MI, and optimal antiaggregant therapy should be administered.     

狼疮肾炎患者肾组织CD40及其配体表达的免疫组织化学分析

目的　探讨CD40 CD40配体 (CD40L)相互作用在狼疮肾炎 (LN)发病机制中的可能作用。方法　用免疫组织化学方法对 2 0例LN患者肾组织CD40和CD40L的表达进行检测 ,并对其与肾脏病变的相关性进行分析。结果　Ⅲ、Ⅳ型LN肾组织CD40表达较正常对照组显著上调 (P <0 0 1) ,除系膜细胞、内皮细胞和肾小管上皮细胞CD40表达增强外 ,还出现CD40阳性的间质浸润细胞。Ⅲ、Ⅳ型LN患者肾组织CD40L表达亦显著增强 (P <0 0 1) ,其分布范围与CD40一致。Ⅱ、Ⅴ型LN患者肾组织CD40表达范围和强度与正常肾组织大致相似。LN肾组织CD40表达与病变活动指数相关 (r =0 78,P <0 0 1)。结论　CD40 CD40L在肾脏局部的相互作用可能在LN发生和发展中起重要作用。     

Soluble CD40 ligand, platelet surface CD40 ligand, and total platelet CD40 ligand in atrial fibrillation: relationship to soluble P-selectin, stroke risk factors, and risk factor intervention

BACKGROUND: Abnormal levels of soluble CD40 ligand (sCD40L) have been reported in patients with hypertension, coronary artery disease, diabetes mellitus, heart failure, and stroke, all of which are conditions that are associated with nonvalvular atrial fibrillation (AF). We hypothesized the following: (1) CD40 ligand (CD40L)-related indexes (ie, platelet surface expressed CD40L, the soluble fragment of CD40L [sCD40L], and the total amount of CD40L per platelet [pCD40L]) are elevated in patients with AF compared to control subjects; (2) these indexes correlate with soluble P-selectin (sP-selectin), which is an established platelet marker; and (3) these indexes differentiate "high-risk" from "low-risk" subjects. METHODS: We performed a case-control study of 121 AF patients, 71 "disease control subjects," and 56 "healthy control subjects." Peripheral venous levels of platelet surface-expressed CD40L were analyzed by flow cytometry, while levels of sCD40L, pCD40L, and sP-selectin were measured by enzyme-linked immunosorbent assay. RESULTS: AF patients had significantly higher sCD40L levels compared to healthy control subjects (p = 0.042), with no difference in platelet surface CD40L and pCD40L levels. A positive correlation was noted between levels of sCD40L and pCD40L, and not with sP-selectin. CD40L-related indexes failed to distinguish between high-risk and low-risk AF patients. AF patients receiving optimal antithrombotic therapy had significantly lower pCD40L levels (p < 0.001) compared to control subjects. Optimized AF management also resulted in significant reductions in the levels of sCD40L (p = 0.023) and pCD40L (p < 0.001). CONCLUSION: CD40L-related indexes are not useful in the risk stratification of AF patients, and abnormal sCD40L levels can be reduced by intense multifactorial risk management. While there is a significant, albeit modest, excess of platelet activation in AF patients (as measured by sCD40L levels) compared to healthy control subjects, this is not in excess of that seen in patients with underlying cardiovascular diseases.     

rshCD_（40）L、IFN-γ对食管癌Eca109、Eca9706、TE13细胞增殖和凋亡的影响

目的观察可溶性重组人CD40L（rshCD40L）、IFN-γ对食管癌Eca109、Eca 9706、TE13细胞增殖和凋亡的影响。方法取正常培养的食管鳞癌细胞株Eca109、Eca 9706、TE13,分别用PBS、100 U/ml IFN-γ、100 ng/ml rsh-CD40L、100 U/ml IFN-γ＋100 ng/ml rshCD40L培养,分别为A、B、C、D组。用MTT法测算各组细胞增殖抑制率,用TUNEL法检测细胞凋亡率。结果 C组Eca109、Eca9706、TE13细胞增殖抑制率分别为40.6%±4.2%、31.5%±5.7%、44.6%±6.7%,明显高于A、B组（P均〈0.05）;D组分别为56.7%±4.9%、41.2%±6.2%、51.6%±5.2%,均高于C组（P均〈0.05）。C组Eca109、Eca9706、TE13细胞凋亡率分别为33.6%±3.7%、30.5%±2.8%和37.6%±4.9%,明显高于A、B组（P均〈0.05）;D组分别为43.7%±4.7%、34.2%±5.1%、41.5%±5.7%,均高于C组（P均〈0.05）。结论 rshCD40L能促进食管癌Eca109、Eca9706、TE13细胞凋亡,并抑制其增殖。IFN-γ可增强这一作用。     

Expression of CD40 and its ligand, CD40L, in intestinal lesions of Crohn's disease

OBJECTIVE: Selected mechanisms of the immune system participate in the development of inflammatory bowel disease. Recently, overexpression of the ligand for CD40 (CD40L), a lymphocyte costimulatory molecule, was shown to induce severe inflammatory bowel disease in transgenic mice. In the present study, we examined the expression of CD40 and CD40L on surgical specimens of ileum from 12 patients with Crohn's disease and 10 patients with diverticulitis. METHODS: Several CD40L+ cells were present in the affected tissue of patients with Crohn's disease, whereas few scattered CD40L+ cells were detected in sections of histologically normal ileum, resected distantly from the affected tissue, in patients with diverticulitis and in normal ileum portions obtained from colorectal cancer undergoing extensive surgery. The phenotype of CD40L+ cells was mainly CD4+. RESULTS: In patients with Crohn's disease, several CD40+ cells were detectable in the same areas of lymphocytes expressing CD40L, whereas in patients with diverticulitis, the number of CD40+ cells was significantly lower. Most of the CD40+ cells costained with CD20, thus showing to be B-lymphocytes, and only a few were CD14+ macrophages. Several von Willebrand-positive vessels were also positive for CD40. In addition, several infiltrating macrophages were found to express B7-1 and B7-2 molecules, the ligands of CD28 and CTLA-4, which cooperate with the CD40-CD40L pathway in lymphocyte activation. Staining of ileal lesions with anti-CTLA-4 antibodies resulted in detection of none or very few positive cells. In contrast, in patients with diverticulitis, an enhanced number of B7-1 and B7-2 and CTLA-4 was observed. CONCLUSION: The local accumulation of CD40L+ together with CD40+ cells within intestinal lesions of Crohn's disease suggests the involvement of this co-stimulatory pathway.     

共刺激分子CD40/CD40L及B7/CD28与动脉粥样硬化

共刺激分子CD40/CD40L及B7/CD28是T细胞活化的两条重要辅助刺激通路,不仅在调节T细胞免疫反应中起关键作用,而且也在B细胞的活化、增殖、分化、抗体的分泌起重要作用.近年来它们在动脉粥样硬化方面的研究成为国内外学者研究的热点.对共刺激分子和动脉粥样硬化关系的深入了解,将有助于阐明动脉粥样硬化发生的炎症和免疫机制,并为临床治疗开辟新途径.本文综述了共刺激分子的免疫学特征及功能以及在动脉粥样硬化中发挥的作用与免疫学治疗的前景.     

CD40/CD40L系统与动脉粥样硬化

动脉粥样硬化是一种慢性炎症性疾病.动脉粥样硬化斑块破裂和血栓形成可导致急性心脑血管事件.炎性介质CD40/CD40L广泛存在于与动脉粥样硬化相关的细胞,参与斑块内炎症反应,释放促炎细胞因子,降解细胞外基质,提高促凝活性,促进动脉粥样硬化的进展和斑块易损性.干预CD40/CD40L信号系统可能成为减缓动脉粥样硬化进展和稳定动脉粥样硬化斑块的一种有效治疗策略.