Identification of neutrophil chemotactie factors in bronchoalveolar lavage fluid of asthmatic patients

Background Although neutrophils have been implicated in bronchial asthma, the mechanism(s) which bring these cells into the airways is poorly understood. Objective To investigate the presence and identity of neutrophil chemotactic factors in bronchoalveolar lavage (BAL) fluid from atopic asthmatic subjects. Method BAL fluid was obtained from 13 subjects (seven asthmatics and six normals). aged 19 to 60 yr, at bronchoscopy. Separation of neutrophil chemotactic activity (NCA) was achieved by FPLC cation exchange chromatography. Fractions were collected and assayed for chemotaxis multiwell micro-chemotaxes chambers using polycarbonate filters, for the complement peptide C5a/C5a des Arg by radioimmunoassay (RIA) and for interleukin-8 (IL-8) by ELISA. Results NCA was found in FPLC fractions of BAL samples in four out of seven asthmatics and each of these subjects had at least three similar peaks of NCA. The major peak of NCA was found to contain immunoreactive C5a/C5a des Arg and chemotaxis. In response to this NCA could be blocked by desensitization of the neutrophils with recombinant C5a. Purified serum derived C5a/C5a des Arg was found to have altered chromatographic properties when added to BAL fluid; this suggested that BAL fluid contained proteins which interacted with the C5a/C5a des Arg. Immunoreactive IL-8 (iIL-8) was also detected but its concentration or chemical form was insufficient to induce neutropbil chemotaxis. Conclusion This study demonstrates that bronchial asthmatic lavage fluid contains C5a/C5a des/Arg and iL-8, together with other as yet unidentified factors which may contribute to neutropbil recruitment in this disease.     

Human T cells that have been conditioned by the proteolytic activity of the major dust mite allergen Der p 1 trigger enhanced immunoglobulin E synthesis by B cells

BACKGROUND: We have previously demonstrated that the proteolytic activity of Der p 1 selectively cleaves human CD25, the 55 kDa alpha subunit of the IL-2 receptor. As a result of cleavage of surface CD25, peripheral blood T cells produce less IFN-gamma and more IL-4, thereby leading to progressive polarization of the T cells towards a Th2 cytokine profile. Therefore, these observations underline the potential role of the proteolytic activity of Der p 1 in creating a microenvironment conducive for IgE synthesis. OBJECTIVE: To study the effect of T cells that have been conditioned by the proteolytic activity of Der p 1 on IgE synthesis by B cells. METHODS: We have examined this concept in experiments whereby T cells that have been exposed to either proteolytically active or inactive Der p 1 were cocultured with autologous B cells and IgE antibody synthesis was monitored. RESULTS: Here we demonstrate for the first time that coculturing T cells that have been in contact with proteolytically active Der p 1 with autologous B cells leads to augmentation of IgE antibody responses. CONCLUSIONS: The proteolytic activity of Der p 1 conditions human T cells, which then become empowered to trigger enhanced IgE synthesis by B cells.     

肾康宁对肾小球肾炎治疗作用的实验及临床研究

目的:观察中药肾康宁对家兔实验性肾炎黏附分子及细胞因子表达的影响,以及临床肾小球肾炎治疗前后尿蛋白的变化.方法:检测牛血清白蛋白所致急性实验性肾炎动物肾组织ICAM-1表达、血清IL-6水平的变化,以及临床肾小球肾炎肾康宁治疗前后血清IL-6水平、尿蛋白的变化.结果:肾康宁能明显降低实验动物血清IL-6含量,降低急性实验性肾炎模型中ICAM-1阳性细胞表达率,同时减轻肾小球基底膜(GBM)增厚及炎症细胞浸润,阻止毛细血管内微血栓的形成;在临床肾小球肾炎中,肾康宁能减少肾小球肾炎患者血清IL-6水平及24 h尿蛋白含量.结论:肾康宁通过降低细胞因子IL-6水平和黏附分子ICAM-1的表达,从而抑制免疫细胞的趋化、浸润、活化和增殖、减少免疫复合物的沉积,使肾小球炎症反应减轻,有效缓解家兔急性实验性和临床肾小球肾炎,使肾功能得以改善.     

Keratinocyte-derived Cytokines and UVB-Induced Immunosuppression

Ultraviolet radiation (UVB) in sunlight is known to have multiple effects on the immune system. Evidence suggests that UVB-induced immunosuppression is mediated in part by immunosuppressive and immunoregulatory cytokines. Our studies have utilized gene-targeted mutant mice to determine key molecular requirements essential for the development of UVB-induced immunosuppression. Preliminary results from our laboratory suggest that TNF-α plays a regulatory role in contact hypersensitivity, but is not a crucial factor for UVB-induced immunosuppression, and that multiple factors are involved in the induction of UVB mediated immunosuppression.     

Identification of N2 as a metabolite of acetylhydrazine in the rat

 In the pathogenesis of isoniazid-induced hepatic injury, cytochrome P450-dependent metabolic activation of the metabolite, acetylhydrazine (AcHz), is the crucial step. Exhalation of [¹⁴C]-carbon dioxide has previously been used to quantify indirectly this pathway. In contrast, according to the current concept of AcHz bioactivation, molecular nitrogen is produced directly, but has not yet been identified. Here, we measured [¹⁵N]-nitrogen and ¹⁴CO₂ exhalation, after the administration of [¹⁵N₂]-[¹⁴C]-AcHz, in rats. Laser magnetic resonance (LMR) spectroscopy, a new sensitive and specific technique for the measurement of ¹⁵N and ¹⁴N in gas samples, was used. To demonstrate the involvement of cytochrome P450, rats were treated with phenobarbital (PB) or PB + cobalt(II) chloride (CoCl₂) (n=3 in each group). Time-dependent ¹⁵N₂ exhalation differed significantly between treatment groups (p<0.001). At 240 min, cumulative exhalation of ¹⁵N was 1.92±0.43% (mean±SE) of the dose in the control group, 2.53±0.23% in the PB group, and 1.00±0.15% in the PB+CoCl₂ group (p<0.05 compared to controls, p<0.01 compared to PB). Cumulative exhalation of ¹⁴CO₂ in 24 h ranged from 15.1 to 21.9%, with no significant difference between treatment groups. In conclusion, N₂ is a metabolite of AcHz. N₂ formation reflects the cytochrome P450-mediated activation of AcHz and can be used as an index of this pathway. Generally, LMR spectroscopy is valuable for monitoring any N₂-liberating process in vivo. Received: 14 March 1995/Accepted: 15 August 1995     

LAK/IL-2联合应用治疗晚期肺癌的临床研究

选择４６例晚期肺癌患者应用ＬＡＫ／ＩＬ－２疗法观察患者近期临床改善情况及治疗前后其免疫指标的变化情况。选择胎儿胸腺淋巴组织作前体细胞，体外用重组ＩＬ－２诱导制备ＬＡＫ细胞，每输３次ＬＡＫ细胞为１疗程，每次输入细胞数为０５×１０９，化疗以采用丝裂霉素、长春新碱、顺铂或卡铂、鬼臼乙叉甙为主的方案，治疗结果：本组患者治疗有效率（ＣＲ＋ＰＲ）达７０％，同时患者免疫指标好转。本研究提示ＬＡＫ／ＩＬ－２联合疗法临床近期疗效较满意，同时可显著改善机体免疫功能，是晚期肺癌患者一种可行的有效方法     

乙型肝炎患者可溶性白细胞介素2受体水平变化

本研究应用酶联免疫吸附试验(ELISA)检测了103例乙型肝炎各型患者及26倒乙肝病毒(HBV)携带者血清中可溶性白细胞介素2受体(sIL-2R)水平,并结合临床资料进行分析。结果发现:各型患者及HBV 携带者sIL-2R 水平均明显高于正常对照(P<0.01～0.001),其升高程度与病情轻重呈正比,在去除危重患者酶—胆分离时谷丙转氨酶(ALT)过低的影响后,sIL-2R 水平与ALT 有良好的正相关关系(r=0.38.p<0.05);作者认为sIL-2R 能够较好地反映疾病的活动状况,动态观察血清sIL-2R 水平的变化,对判断和评价HBV 感染后的病情演变及免疫失衡状态具有重要意义。     

Immunoregulatory Effect of Substance P in Human Eosinophil Migratory Function

Substance P (SP) is a tachykinin involved in the regulation of inflammatory processes. To investigate a modulatory role of the neuropeptide SP in allergic inflammation, we studied its priming effect on human eosinophil chemotaxis and kinetic responses towards platelet activating factor (PAF) and recombinant human interleukin 5 (rhlL-5). Blood was obtained from normal subjects and eosinophils were separated by Percoll discontinuous density gradient centrifugation. High purification was obtained by negative selection procedure (CD16-beads) and the experiments were performed in a 48-well microchemotaxis Boyden chamber. In the present study we demonstrate a potent synergistic effect of 100nM dose of SP on the migratory function of human eosinophils stimulated by PAF and rhIL-5. This synergism was chemotaxis specific and was abolished by NK-1 receptor antagonist (FK888). The results suggest that neurogenic stimuli may play a significant role in eosinophil infiltration via its priming effect on the cell.     

Respiratory failure in mice caused by a hybridoma making antibodies to the 15 kDa surfactant apoprotein

Hybridoma cells were obtained by fusing spleen cells from mice, immunized against the 15 kDa porcine surfactant apoprotein, with a myeloma cell line. Adult mice were inoculated intraperitoneally with this hybridoma; mice that were not inoculated or were inoculated with myeloma cells served as controls. Lung-thorax compliance was measured at various intervals after inoculation. The animals were then killed for histologic-morphometric evaluation of alveolar air expansion, inflammatory reaction in the pulmonary parenchyma, and intraalveolar edema. In the hybridoma group, the mice developed respiratory failure 9 days after inoculation, with markedly reduced lung-thorax compliance, lung congestion, alveolar collapse, hemorrhagic pulmonary edema, and hyaline membranes. Morphometric data from the same animals showed reduced volume density of alveolar air, and increased volume densities of intraalveolar "fluid" (edema) and tissue components. These lung lesions are similar to those in the adult respiratory distress syndrome.     

The effect of RO15-1788 on cardiovascular depression caused by fentanyl and diazepam

Cardiovascular depression occuring when diazepam is combined with fentanyl has been investigated using the benzodiazepine antagonist RO15-1788 in the dog.After the initial administration of fentanyl (40mcg/kg), the mean arterial pressure (MAP) decreased to 89% of its control value. Following the administration of diazepam (1.2mg/kg), the MAP and the total peripheral resistance (TPR) decreased significantly, to 75% and 83% of their control values respectively. After the administration of RO15-1788 (0.4mg/kg), the MAP increased significantly to 90% and the TPR to 102% of their control values and, lastly, the administration of naloxone (40mcg/kg) increased the MAP to 108% of its control value. No relationship was found between the changes in the catecholamines and the changes in the MAP after the administration of fentanyl, diazepam, and RO15-1788.The mechanism of circulatory depression when diazepam was used with fentanyl is interpreted as being a peripheral vasodilatory effect of diazepam acting by way of the benzodiazepine receptors since RO15-1788 was found to antagonize this effect.(Sone T, Kato T, Tsukahara I et al.: The effect of RO15-1788 on cardiovascular depression caused by fentanyl and diazepam. J Anesth 2: 69–76, 1988)