青春型双歧杆菌脂磷壁酸对巨噬细胞的免疫活性影响

双歧杆菌的脂磷壁酸 (ｌｉｐｏｔｅｉｃｈｏｉｃａｃｉｄ ,ＬＴＡ)有较强的免疫活性作用 ,能激活巨噬细胞以及增强单核细胞的呼吸暴发。作者观察了青春型双歧杆菌的ＬＴＡ刺激小鼠腹腔巨噬细胞后分泌的ＴＮＦ α活性以及ＩＬ 12、ＮＯ的含量 ,同时检测巨噬细胞的体外杀瘤活性 ,旨在探讨它对巨噬细胞的免疫调节作用。材料与方法ＬＴＡ :按照文献从青春型双歧杆菌中提取ＬＴＡ。提取的ＬＴＡ分别经紫外扫描和化学组分分析证实无明显蛋白质以及核酸污染。被动血球凝集试验显示ＬＴＡ能自主粘附鸡红细胞。实验动物 :ＢＡＬＢ/ｃ小鼠 ,雌雄各半 ,…     

双歧杆菌脂磷壁酸激活巨噬细胞活性机制的研究

目的：从信号分子PKC和细胞内游离Ca^2 ([Ca^2 ]i)这一途径探索青春型双歧杆菌的脂磷壁酸（lipoteichoic acid,LTA)激活小鼠腹腔巨噬细胞的机制，同时观察巨噬细胞之间缝隙连接通讯（GJIC）的变化。方法：γ-^32P ATP磷酸转移法测定巨噬细胞总PKC活性；激光共聚焦显微镜检测[Ca^2 ]i浓度的变化；激光漂白后荧光恢复技术（FRAP）观察GJIC的状态。结果：（1）LTA能明显提高巨噬细胞总PKC活性，呈剂量依赖性；（2）LTA可显著升高巨噬细胞[Ca^2 ]i的水平，并且EDTA和维拉帕米处理组、肝素和普鲁卡因处理组以及EDTA、维拉帕米、肝素和普鲁卡因处理组巨噬细胞内[Ca^2 ]i亦升高，但明显低于对照组（P＜0．01）。（3）巨噬细胞被LTA刺激后，其平均荧光恢复率明显高于对照组（P＜0．01）。结论：LTA可通过提高PKC活性，升高[Ca^2 ]i的水平以及增强GJIC的功能来激活巨噬细胞。     

双歧杆菌的脂磷壁酸对小鼠腹腔MΦ的激活作用

目的 探讨青春型双歧杆菌的脂磷壁酸（LTA）对MΦ功能的影响。方法 将LTA注射于小鼠腹腔，分别采用中性红吞噬试验，MTT法，小鼠胸腺细胞增殖法和ELISA法，检测MΦ的吞噬能力，能量代谢水平，IL－1的活性及IL－6含量。结果 LTA注射组小鼠腹腔MΦ的吞噬能力，能量代谢水平，IL－1活性及IL－6含量均显著高于对照组（P＜0．01）。结论 双歧杆菌的LTA能激活MΦ，提高其吞噬能力和能量代谢水平，同时可分泌多种的具有杀瘤作用的活性因子。     

双歧杆菌脂磷壁酸对结肠癌细胞Toll样受体表达的影响

目的通过研究双歧什菌脂磷壁酸（lipoteichoic acid，LTA）对结肠癌细胞中Toll样受体（TLR）表达的影响，探讨TLR在启动双歧杆菌LTA抗肿瘤信号转导通路中的作用。方法用RT-PCR检测结肠癌细胞HCT-116经双歧杆菌LTA处理前后11R的表达变化。结果结肠癌HCT-116细胞有TLR的基础表达，且经LTA处理后受体的表达增强，呈剂量依赖件。结论双歧杆菌LTA可上调TLR的表达，提示双歧杆菌LTA诱导肿瘤细胞凋亡的信号转导途径可能由TLR启动。     

金黄色葡萄球菌脂磷壁酸纯化及其抗肿瘤的初步研究

目的从金黄色葡萄球菌细胞壁中提取脂磷壁酸(LTA),研究其抗肿瘤活性。方法冷酚法提取LTA,经SepharoseCL4B纯化,检测LTA毒性;观察荷瘤小鼠注射LTA后的生命延长率及抑瘤率,NK细胞活性,TNFα、IFNγ分泌。结果LTA未见明显毒性,能提高荷瘤小鼠生命延长率;明显抑制实体瘤生长;提高NK细胞活性;诱导分泌多量TNFα及IFNγ。结论LTA可通过提高NK细胞活性,诱导分泌多量TNFα及IFNγ等细胞因子发挥抗肿瘤活性。     

双歧杆菌脂磷壁酸对HL-60细胞端粒酶活性的影响

目的 探讨双歧杆菌表面分子脂磷壁酸（ＬＴＡ）对体外培养的ＨＬ－６０白血病细胞端粒酶活性的影响。方法 采用ＰＣＲ－ＥＬＩＤＡ法检测经ＬＴＡ处理前后的ＨＬ－６０白血病细胞株端粒酶活性的改变。结果 经ＬＴＡ处理后,ＨＬ－６０白血病细胞的生长受到抑制,端粒酶活性明显降低。结论 双歧杆菌ＬＴＡ对ＨＬ－６０白血病细胞具有生长抑制作用,其抗肿瘤作用的机理可能与抑制肿瘤细胞的端粒酶活性有关。     

双歧杆菌脂磷壁酸延缓脾脏衰老的研究

目的　研究双歧杆菌表面分子脂磷壁酸 (LTA)在D 半乳糖诱导的衰老小鼠体内 ,对脾脏指数和脾细胞DNA损伤的影响。方法　在建立D 半乳糖诱导的衰老小鼠模型的同时 ,注射双歧杆菌LTA ;然后测定模型对照组、正常对照组、试验组小鼠的脾脏指数 ,并以单细胞凝胶电泳试验检测脾脏淋巴细胞DNA氧化损伤的情况。结果　与正常对照组相比 ,模型对照小鼠的脾脏指数显著升高 (P <0 .0 5 ) ,脾淋巴细胞DNA受到了较严重的损伤 (P <0 .0 5 ) ;用双歧杆菌LTA处理后 ,试验小鼠的脾脏指数明显下降 (P <0 .0 5 ) ,脾淋巴细胞DNA的损伤程度显著降低 (P <0 .0 5 )。结论　双歧杆菌LTA能显著抑制衰老小鼠脾脏淋巴细胞DNA的氧化损伤 ,这可能与双歧杆菌抗衰老有关。     

双歧杆菌脂磷壁酸抗免疫衰老的实验研究

目的：探讨双歧杆菌抗衰老的分子机理。方法：在建立D-半乳糖诱导的衰老小鼠模型的同时，每日注射双歧杆菌LTA。检测各组小鼠体重增长曲线、胸腺形态、胸腺指数、用免疫组化方法检测胸腺c-fos、p16蛋白表达及用ELISA法检测外周血IL-2的含量。结果：与青年对照组小鼠相比，衰老模型组小鼠胸腺组织形态结构异常，体重、胸腺指数、胸腺c-fos蛋白表达与外周血IL-2含量显著下降，胸腺p16蛋白表达显著升高；而双歧杆菌LTA，能显著逆转上述这些变化。结论：双歧杆菌LTA具有抗衰老作用。     

莫西沙星序贯治疗老年社区获得性肺炎效果及对肺功能的影响

目的 研究莫西沙星序贯治疗对老年社区获得性肺炎效果及对肺功能的影响。方法 选取2018年2月~2020年2月我院治疗的100例老年社区获得性肺炎患者为研究对象,采用随机数字表法分为对照组和观察组,各50例。对照组采用莫西沙星静滴治疗,观察组采用莫西沙星序贯治疗,比较两组临床治疗效果、肺功能指标、临床症状评分、炎症指标以及临床不良反应发生情况。结果 观察组治疗总有效率为96.00%,高于对照组的84.00%,差异有统计学意义（P＜0.05）;观察组FEV1、FVC、FEV1/FVC高于对照组,差异有统计学意义（P＜0.05）;观察组咳嗽、咳痰、起初、肺部湿啰因评分低于对照组,差异有统计学意义（P＜0.05）;观察组WBC、CRP水平对照组,差异有统计学意义（P＜0.05）;观察组不良反应发生率为6.00%,低于对照组的14.00%,差异有统计学意义（P＜0.05）。结论 莫西沙星序贯治疗老年社区获得性肺炎效果可提高总有效率,改善肺功能指标,降低临床症状评分和炎症因子水平,且临床不良反应发生率低,具有确切的应用有效性和安全性。     

Presentation of lipoteichoic acid potentiates its inflammatory activity

Lipoteichoic acid (LTA) is a major immunostimulatory molecule in the cell wall of Gram-positive bacteria. Adhesion of LTA to a polystyrene surface drastically increased its immunostimulatory potency in human whole blood in comparison to soluble LTA, although only 1% of the LTA had bound, as determined using rhodamine-labelled LTA. The release of the proinflammatory cytokines IL-1beta, TNF and IL-6 and the chemokines IL-8 and G-CSF was increased 2- to 10-fold, but IL-10 release was unaltered. This presentation effect was not shared by lipopolysaccharide (LPS) or other toll-like receptor 2 agonists and was less pronounced in polypropylene vessels. LTA did not induce cytokine release in silicone-coated borosilicate vessels, but covalent coupling of LTA to polystyrene beads restored cytokine induction in these vessels, indicating that presentation of LTA on a surface is in fact essential for its immunostimulatory potency. This novel aspect of presentation as a factor in the recognition of LTA may reflect the physiological situation in the bacterial cell wall, where LTA is anchored in the bacterial membrane and projects through the peptidoglycan. In practical terms, contamination of medical devices with components of Gram-positive bacteria may pose an underestimated inflammatory risk.     

Manganese superoxide dismutase induced by lipoteichoic acid isolated from Staphylococcus aureus regulates cytokine production in THP-1 cells

Lipoteichoic acid isolated from Staphylococcus aureus (aLTA) is known to regulate the production of pro-inflammatory cytokines through TLR2-mediated signaling pathways. In our previous study, we found that aLTA significantly increased manganese superoxide dismutase (MnSOD) in the THP-1 human monocyte-like cell line, but the role of MnSOD in the regulation of cytokine production was not elucidated. In the current study, we found that MnSOD was involved in aLTA-mediated cytokine production. The signaling pathways associated with aLTA-mediated MnSOD induction in THP-1 cells included TLR2-MyD88-IRAK2, JNK (c-Jun N-terminal kinases)1/2 and nuclear factor- κB (NF-κB). We also found MnSOD was involved in the regulation of IL-1β and TNF-α, which were induced by early signaling pathways, including JNK1/2, p38, and NF-κB p65. In addition, MnSOD was also involved in the production of IL-6 and CCL2 in aLTA-stimulated THP-1 cells through activation of late signaling pathways such as JAK2-STAT3. Taken together, our data suggest that aLTA-mediated MnSOD production involved in the regulation of cytokine production and it may be the cause of one of the excessive inflammatory reactions caused by S. aureus.     

一氧化氮对香烟烟雾提取物诱导大鼠肺泡巨噬细胞核因子кB活化的影响

目的:探讨一氧化氮(NO)对香烟烟雾提取物(CSE)诱导的大鼠肺泡巨噬细胞(AM)中核因子κB(NF—κB)活化的影响及机 制。方法:将大鼠AM与不同浓度的NO前体左旋精氨酸(L-Arg)或iNOS特异性抑制剂N6-(1-亚氨乙基)赖氨酸(L-NIL)及CSE共同培养,用免疫细胞化学染色法检测NF-κB,用Western blot检测I-κB蛋白含量,用Griess法测定培养上清液中NO的水平。结果:CSE可使NF-κB活化细胞的百分率增加,I-κB的水平下降。加入CSE和低浓度L-Arg培养的AM,NF-κB活化细胞的百分率显著高于只加入CSE的AM;而I-κB的水平显著低于只加入CSE的AM。加入CSE和高浓度L-Arg培养的AM,NF-κB活化细胞的百分率显著低于只加入CSE的AM,而I-κB的水平无显著变化。加入CSE和不同浓度的L-NIL培养的AM,NF-κB活化细胞的百分率显著低于只加入CSE的AM;而I-κB的水平则显著高于只加入CSE的AM,并呈浓度依赖(P<0.01)。结论:内源性NO对香烟烟雾所致NF-κB的活化具有双向调控作用。     

一氧化氮对香烟烟雾提取物诱导大鼠肺泡巨噬细胞核因子κB活化的影响

目的:探讨一氧化氮(NO)对香烟烟雾提取物(CSE)诱导的大鼠肺泡巨噬细胞(AM)中核因子κB(NF—κB)活化的影响及机 制。方法:将大鼠AM与不同浓度的NO前体左旋精氨酸(L-Arg)或iNOS特异性抑制剂N6-(1-亚氨乙基)赖氨酸(L-NIL)及CSE共同培养,用免疫细胞化学染色法检测NF-κB,用Western blot检测I-κB蛋白含量,用Griess法测定培养上清液中NO的水平。结果:CSE可使NF-κB活化细胞的百分率增加,I-κB的水平下降。加入CSE和低浓度L-Arg培养的AM,NF-κB活化细胞的百分率显著高于只加入CSE的AM;而I-κB的水平显著低于只加入CSE的AM。加入CSE和高浓度L-Arg培养的AM,NF-κB活化细胞的百分率显著低于只加入CSE的AM,而I-κB的水平无显著变化。加入CSE和不同浓度的L-NIL培养的AM,NF-κB活化细胞的百分率显著低于只加入CSE的AM;而I-κB的水平则显著高于只加入CSE的AM,并呈浓度依赖(P<0.01)。结论:内源性NO对香烟烟雾所致NF-κB的活化具有双向调控作用。     

牵张应变诱导人牙周膜细胞凋亡过程中caspase蛋白酶表达的初步研究

目的研究在牵张应变诱导人牙周膜细胞凋亡过程中caspase蛋白酶表达的变化。方法对体外培养的人牙周膜细胞分别施加20%牵张应变6、24 h,采用流式细胞术测定细胞凋亡率,采用免疫印迹技术检测caspase-3、-5、-7、-8、-9的蛋白表达,并采用分光光度比色法测定caspase-3、-5、-8、-9的蛋白酶活性变化。结果 20%牵张应变加载6、24 h可诱导人牙周膜细胞发生凋亡。caspase-3的蛋白表达及蛋白酶活性和caspase-7的蛋白表达在24 h牵张应变作用下较对照组增加,caspase-5、-8、-9的蛋白表达及蛋白酶活性在6、24 h牵张应变作用下较对照组增加。结论 20%牵张应变能诱导体外培养的人牙周膜细胞凋亡,此过程中伴随发生了caspase-3、-5、-7、-8、-9蛋白酶的活化。     

Delineation of pulmonary alveolar macrophage subpopulations by flow cytometry in normal subjects and in patients with lung cancer

We have previously described alterations in pulmonary alveolar macrophage (PAM) function in patients with lung cancer when compared with control subjects. This study examined PAM from five patients with lung cancer, seven normal volunteers and nine control patients, to assess whether any differences in surface phenotypic markers were present in lung cancer versus non-cancer subjects, and what changes might be induced with interferon-gamma (IFN-γ) stimulation. After 3 days’culture with or without IFN-γ no differences were seen in the percentages of cells staining positively in each group for HLA class I. class II and ICAM-1 (CD54) antigens. However, in 13 out of 14 control subjects, and only one out of the five cancer subjects, dual PAM populations were identified. The second PAM population (PAM-2) was larger and demonstrated a higher expression of class I and ICAM-1 antigens. Unlike the unfractionated PAM population, PAM-2 consistently responded to IFN-γ stimulation with an increase in both class I (90 ± 25%) and ICAM-1 (45 ± 10%) antigens, while there was no change in class II antigen expression. In three subjects PAM-2 was found to induce a significantly greater mitogen response than the rest of the PAM population. If confirmed in a larger group of patients, the absence of PAM-2 in the majority of patients with lung cancer may underlie the functional PAM defects observed in these patients.     

Characterization of CD44 expressed on alveolar macrophages in patients with diffuse panbronchiolitis.

Interleukin (IL)-8 may play an important role in neutrophil infiltration in the airways of patients with diffuse panbronchiolitis (DPB). Furthermore, alveolar macrophages could produce IL-8 subsequent to CD44-hyaluronic acid (HA) interaction. The purpose of this study was to evaluate the contribution of CD44 expressed on alveolar macrophages to the pathogenesis of DPB. We examined the concentration of soluble CD44 (sCD44) in bronchoalveolar lavage fluid (BALF) and CD44 expression on macrophages in BALF from patients with DPB before and after low-dose, long-term macrolide therapy. We also assessed the HA-binding ability of alveolar macrophages as a functional analysis of the CD44 molecule. The sCD44 concentration in BALF was significantly lower in patients with DPB than in healthy volunteers. Percentages of alveolar macrophages expressing low CD44 (CD44 low(+)) and HA-nonbinding alveolar macrophages were higher in patients with DPB compared with healthy volunteers. Furthermore, macrolide therapy normalized CD44 expression and HA-binding ability of macrophages in BALF from DPB patients. Our findings suggest that alveolar macrophage dysfunction could result from abnormalities of CD44 expression in patients with DPB and that these events could contribute to the pathogenesis of DPB.     

Ajulemic acid,a nonpsychoactive cannabinoid acid,induces apoptosis in human T lymphocytes

Oral administration of ajulemic acid (AjA), a synthetic nonpsychoactive cannabinoid acid, prevents joint cartilage and bone damage in an experimental model of arthritis in rats. Joint tissue injury in patients with rheumatoid arthritis (RA) is due in part to activation of T lymphocytes in the synovium, and T lymphocytes in synovium of RA patients are resistant to apoptosis. Thus, a potential mechanism whereby AjA prevents joint tissue injury in the animal model might be enhanced apoptosis of T lymphocytes. Apoptosis of human T cells in vitro was assessed by Annexin V expression, caspase-3 activity, DNA fragmentation, and microscopy. AjA induced apoptosis of T cells in a dose- and time-dependent manner. Apoptosis preceded loss of cell viability by trypan blue dye exclusion, confirming that cell loss was due to programmed cell death rather than necrosis. A nontoxic compound such as AjA may be a useful therapeutic agent for patients with diseases such as RA which are characterized by T-cell-driven chronic inflammation and tissue injury.