高压氧对急性移植物抗宿主病小鼠细胞因子表达的影响

目的:观察高压氧(HBO)对骨髓移植时急性移植物抗宿主病(aGVHD)小鼠脾组织中细胞因子表达的影响,探讨HBO抗aGVHD的作用机制.方法:应用直线加速器排空C57BL/6小鼠骨髓后,注入BALB/C小鼠骨髓与脾淋巴细胞的混合液,复制aGVHD模型.应用RT-PCR技术检测经HBO、环孢素A(CsA)、氨甲喋呤(MTX)处理后,小鼠脾组织中白细胞介素2(IL-2)、肿瘤坏死因子α(TNF-α)、白细胞介素4(IL-4)及白细胞介素10(IL-10)mRNA水平的变化.结果:HBO组小鼠11d的生存率明显高于异基因移植组及CsA MTX组;HBO组小鼠脾组织中TNF-α和IL-2mRNA相对含量显著低于异基因移植组(P＜0.05)、显著高于CsA MTX组;HBO组小鼠脾组织中IL-4和IL-10 mRNA相对含量显著高于异基因移植组及CsA MTX组(P＜0.05).结论:HBO可能通过调节促炎/抑炎细胞因子的分泌而发挥其明显的抗aGVHD作用.     

氧化苦参碱对哮喘小鼠抗炎作用的研究

目的：探讨氧化苦参碱治疗哮喘的抗炎作用机制及其对白细胞介素－4（IL－4mRNA)表达的影响。方法：建立小鼠哮喘模型，观察氧化苦参碱对哮喘小鼠支气管肺泡灌洗液中炎性细胞、肺组织病理的改变；应用半定量反转录－聚合酶链反应检测肺组织IL－4mRNA表达的变化。结果：氧化苦参碱可显著减轻哮喘小鼠气道及肺组织中哮酸性细胞的浸润，显著抑制哮喘小鼠肺组织中IL－4mRNA的表达水平。结论：氧化苦参碱对哮喘小鼠有明显的抗气道变应性炎症及抑制IL－4mRNA表达的作用。     

慢性髓性白血病细胞来源的树突状细胞大容量诱导及其功能的实验研究

目的　探索大容量诱导慢性髓性白血病 (CML)细胞来源的树突状细胞 (DCs)的适宜方法 ;研究CML DCs刺激自体T淋巴细胞增殖并分泌γ 干扰素 (IFN γ)的能力。方法　用CS 30 0 0 plus血细胞分离机采集初诊CML病人的外周血单个核细胞 (PBMNCs) ;单采的CML PBMNCS转入组织培养袋 ,加入重组人粒 巨细胞集落刺激因子 (rhGM CSF)和重组人白介素 4 (rhIL 4 ) ,培养诱导 7d ;在诱导前后 ,用流式细胞仪分别检测细胞表面HLA DR、CD1a、CD80和CD86的表达水平 ;用3 H TdR掺入法检测CML DCs和CML PBMNCs刺激自体和异体T细胞增殖的能力 ;用ELISA法检测在自体混合淋巴细胞培养 (MLR)时T细胞分泌的IFN γ浓度。结果　用血细胞分离机收集的CML PBMNCs ,在组织培养袋内经细胞因子培养诱导 ,HLA DR、CD1a、CD80、CD86的表达均有明显上调 ,细胞形态也表现典型的DC特征 ;CML DCs能显著刺激自体和异体T细胞增殖 ,而CML PBM NCs仅能刺激异体T细胞的增殖 ,刺激自体T细胞增殖的能力很弱 ;刺激自体T细胞增殖时分泌的IFN γ浓度 ,CML DCs组为 (877± 2 14 )pg/mL ;CML BPMNCs组仅为 (14± 1.7) pg/mL。 结论　单采的CML PBMNCs转入组织培养袋 ,加入rhGM CSF和rhIL 4 ,可收获大容量的CML DCs;CML DCs在体外具有显著刺激自体T细胞增殖     

大气颗粒物健康效应生物学机制研究进展

大量流行病学研究发现，大气颗粒物的污染水平与心肺系统疾病的超额发病、死亡存在密切关联，但其毒理学机制尚未阐明。本文对近年来大气颗粒物毒理学研究进行综述，包括大气颗粒物对呼吸系统、心血管系统及神经系统的毒性作用，并对氧化应激损伤、细胞钙稳态失衡及激活关键转录因子等分子毒理学机制进行了初步的阐述。     

Nutrition et fonction immunitaireNutrition and immune function

A deficiency of total energy or of one or more essential nutrients, including vitamins A, B₆, B₁₂, C, and E, folic acid, zinc, iron, copper, selenium, essential amino acids and essential fatty acids, will impair immune function and increase susceptibility of the host to infectious pathogens. This is most likely because these nutrients are involved in the molecular and cellular responses to challenge of the immune system. Providing these nutrients to deficient individuals restores immune function and improves resistance to infection. Thus, appropriate nutrition is required in order for the host to maintain adequate immune defences towards bacteria, viruses, fungi, parasites and tumour celîs. Although the intakes of several nutrients which result in greatest enhancement of immune function appear to be greater than recommended intakes, excess intake of certain nutrients also impairs immune responses. Some nutrients (e.g. glutamine, arginine) may become limiting in critical illness and there is mounting evidence that provision of these will aid patient recovery.     

Comparison of the use of bulk to micro culture of cell preparations for lymphokine-activated cytotoxicity assays.

Different assay systems have been used to quantitate lymphokine-induced natural cytotoxic activity as a measure of immune status. This study compares the effects of inducing cytotoxicity in a bulk culture system, where effector cells are transferred to a micro culture well for assay, to a micro culture system where the effector cells are not transferred. The effector/target ratio for both the bulk and micro culture systems was calculated using the number of viable effector cells present at the time of target cell addition. After overnight incubation with interleukin-2 (IL-2), the lytic activity of murine spleen cells to targets using a micro culture system was increased two-fold over the bulk culture method. This increase was amplified further after 5 days of activation with IL-2, in that the micro culture system resulted in a four-fold increase in cytotoxic activity. The loss of some adherent cells in the bulk culture system did not explain the overall decrease in recovered cytotoxicity. The difference appeared to be related to cell loss during centrifugation. Therefore, the E/T ratios are different in the two systems if not corrected for the number of viable cells.     

Different cytokine levels in thrombolysis patients as predictors for clinical outcome

Thrombolytic therapy not always improves clinical outcome in ischemic stroke patients. This could cause lymphomonocyte accumulation in the infarcted brain area. These produce an excessive amount of proinflammatory cytokines, such as IL-1 beta, IL-6 and TNF-alfa. The aim of our study was to determine ILs levels in fibrinolytic therapy treated patients, compared with healthy controls and to evaluate if the varying levels can predictors of neurological outcome. Eighteen patients underwent thrombolytic treatment with t-PA within 3 h. Plasma levels of IL-1 beta, IL-6, TNF-alfa and IL-10 were determined by ELISA method before and within 24 h after t-PA infusion and compared with controls. Significantly higher levels of IL-1 beta and Il-6 emerged in stroke patients before treatment compared with the control group (P < 0.05 and 0.04, respectively). Slightly higher plasma levels of TNF-alfa and lower plasma levels of IL-10 were also found at base line in stroke patients. After thrombolytic treatment no significant variations were observed in the levels of TNF-alfa and IL-6, whereas a trend toward lower values for IL-1 beta and higher levels for IL-10 was observed. Positive correlations among the values of IL-6, TNF-alfa and National Institute of Health Stroke Scale (NIHSS) at discharges were observed. A similar correlation with modified Rankin scale score at 3 month was found. Pre-treatment cytokine status seems to influence pre-and long-term clinical outcome. Therefore an investigation into the possible predictor of cytokines seem worthy.