Association of monoctye expression of Toll-like receptor 4 and its related cytokines with coronary luminal stenosis

Toll-like receptors are well-defined barriers in innate immunity. Among them hTLR4 on the surface of monocytes, plays a critical role in the formation of atherosclerotic plaques, plaque instability and arterial remodeling through production of inflammatory cytokines. This study was designed to examine the association of hTLR4 monocyte expression and response with the severity of coronary stenosis in patients with stable angina (SA). Blood samples were obtained from 39 patients with SA who were scheduled for a coronary angiography and from 28 healthy volunteers. The samples were collected before the procedure. Expression of hTLR4 on CD14+ monocytes and serum levels of TNF-α and IL-1β were measured using flowcytometry and ELISA techniques respectively. Percentage stenosis diameter was measured by comparing the area of coronary stenosis to an adjacent normal segment of the vessel. Compared with control group, patients showed upregulation of hTLR4+/CD14+ monocytes. Furthermore, patients with more severe coronary stenosis exhibited enhanced expression of hTLR4+/CD14+ monocytes (p α (p β. In addition, significant correlations were seen between percentage stenosis diameter and monocyte expression of hTLR4 as well as TNF-α. hTLR4 monocytic expression and related cytokines are positively associated percentage stenosis diameter. These results suggest that hTLR4 activity may be involved in progression of atherosclerosis.

人源抗TLR4抗体IgG2对对乙酰氨基酚诱导小鼠急性肝损伤的保护作用

目的:研究人源抗TLR4抗体IgG2(human-TLR4 IgG2,h TLR4 IgG2)对对乙酰氨基酚(acetaminophen,APAP)诱导肝损伤的保护效应,探讨其在药物性肝损伤中的保护作用。方法:以人源抗TLR4抗体Fab基因为模板,扩增其可变区基因,构建人源抗TLR4抗体IgG2真核表达载体,转染CHO-S细胞,筛选稳定表达细胞株,收集细胞上清,Protein G柱纯化抗TLR4抗体IgG2。将18只C57BL/6J小鼠随机分成3组:生理盐水组、APAP(600 mg/kg)组和APAP+hTLR4 IgG2(5 mg/kg)组,统计小鼠腹腔注射APAP后24 h的存活率;重复上述实验分组,检测小鼠腹腔注射APAP 8 h后,血清中丙氨酸氨基转移酶(alanine aminotransferase,ALT)、天门冬氨酸氨基转移酶(aspartate transaminase,AST)、白细胞介素-1(interleukin-1,IL-1)、白细胞介素-6(interleukin-6,IL-6)和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的表达水平,取肝脏做病理分析并使用Western blot检测凋亡蛋白的表达。结果:成功构建并表达纯化人源抗TLR4抗体IgG2;ELISA结果显示,抗体效价为1∶204800。与APAP组相比,APAP+hTLR4 IgG2组小鼠的24 h存活率显著增加(P<0.05);血清AST、ALT以及炎性细胞因子的表达水平显著降低,具有统计学意义(P<0.05);病理分析结果显示,与模型组相比,人源抗TLR4抗体IgG2治疗组的小鼠肝组织炎性细胞浸润、充血和坏死等症状明显改善;Western blot结果显示凋亡相关蛋白的表达减少。结论:人源抗TLR4抗体IgG2能够抑制炎症因子的表达及细胞凋亡,对APAP诱导的小鼠肝损伤有显著的保护作用。