Complement activation by artificial blood substitute Fluosol: in vitro and in vivo studies

A perfluorocarbon blood substitute, Fluosol, is undergoing clinical trials as an adjunct to chemotherapy. The adverse effects associated with its administration have been postulated to result from complement activation. When gel electrophoresis and Western blotting of Fluosol are used after its incubation with serum, activated C3 and factors Bb and H are bound to the Fluosol particles in a time-dependent fashion, which suggests that complement activation with Fluosol, as does that with zymosan, occurs on the surface of the particles. Paradoxically, it is found, both by the measurement of Fluosol-bound C3d and by fluid-phase C5a, that lower concentrations of Fluosol cause greater amounts of complement activation, which suggests a complex interaction of activators and inhibitors that changes as the available surface area is decreased. Studies performed with bystander red cell-bound C3d demonstrated in vivo complement activation occurring in six patients receiving Fluosol as an adjunct to chemotherapy for colon cancer. In two patients, there was a marked increase in red cell-bound C3d after Fluosol infusion; these two patients also developed adverse reactions during Fluosol infusion. These studies suggest that the Fluosol surface plays a major role in the initiation and regulation of complement activation that is seen during Fluosol infusion.     

冠状动脉粥样硬化性心脏病患者升主动脉弹性与颈动脉内-中膜厚度的相关性

目的:观察冠状动脉粥样硬化性心脏病(简称冠心病)患者升主动脉弹性与颈动脉内膜-中层厚度及粥样斑块发生的相关性。方法:于2005-08/2006-04选择石河子大学医学院第一附属医院心内科行冠状动脉造影检查患者97例,根据冠状动脉造影结果分为正常对照组41例和冠心病组56例,对两组患者进行超声检查,分别测量升主动脉扩张性D、僵硬度指数β、测量升主动脉前壁收缩期S波以及舒张期E波、A波的速度、颈动脉内膜-中层厚度及粥样斑块发生率。僵硬度指数β=In(收缩压/舒张压)/[(收缩期内径-舒张期内径)/舒张期内径]。动脉扩张性D=2(收缩期内径-舒张期内径)/[舒张期内径(收缩压-舒张压)]×10-3m2/N。结果:纳入患者97例,均进入结果分析。①冠心病组升主动脉扩张性D低于正常对照组,差异有显著性意义[分别为(15.02±9.99)×10-4,(34.75±20.80)×10-3m2/N,P=0.001];僵硬度指数β高于正常对照组(分别为28.20±21.06,15.23±25.32,P=0.001);升主动脉前壁S波和E波速度低于正常对照组[分别为(0.08±0.01),(0.10±0.03)m/s;(0.05±0.01),(0.07±0.02)m/s,P=0.001];颈动脉内膜-中层厚度和颈动脉斑块发生率高于正常对照组[分别为(0.90±0.15),(0.66±0.09)mm;41.03%,5.88%,P=0.001]。②升主动脉前壁S波速度与扩张性呈正相关(r=0.43,P=0.003),与僵硬度指数呈负相关(r=-0.47,P=0.002)。升主动脉前壁E波速度与扩张性呈正相关(r=0.47,P=0.002),与僵硬度指数无相关性。升主动脉前壁A波速度与扩张性和僵硬度指数均无相关性。③升主动脉扩张性D与颈动脉内膜-中层厚度呈负相关(r=-0.49,P=0.004),而僵硬度指数β与内膜-中层厚度则呈正相关(r=0.46,P=0.003)。S波速度与内膜-中层厚度无相关性(r=-0.26,P=0.15)。结论:冠心病患者升主动脉弹性降低即动脉扩张性降低、僵硬度指数升高、升主动脉前壁S波速度下降,颈动脉内膜-中层厚度增厚及粥样斑块发生率增高,将这些参数结合可作为冠心病很有价值的预测指标。     

Demonstration by the monoclonal antibody-specific immobilization of erythrocyte antigens assay that a new red cell antigen belongs to the Kell blood group system

BACKGROUND: The Kell blood group system comprises 21 antigens residing on a red cell membrane glycoprotein of apparent M(r) 93,000. STUDY DESIGN AND METHODS: Serologic techniques were used to identify a new red cell antigen. The monoclonal antibody-specific immobilization of erythrocyte antigens (MAIEA) assay was used to identify the red cell membrane component carrying that antigen. RESULTS: A new high-frequency red cell antigen was identified and provisionally named RAZ. RAZ is absent from K.o red cells and from red cells treated with 2-amino- ethylisothiouronium bromide and is expressed weakly on McLeod phenotype cells. It differs from all other Kell system antigens, and no depression of other Kell system antigens on RAZ+ red cells was noticed. The RAZ antigen was shown by the MAIEA assay to be located on the Kell glycoprotein. CONCLUSION: RAZ is a new high-frequency antigen located on the Kell glycoprotein. The MAIEA assay is a very effective method of demonstrating the membrane structure carrying a red cell antigen.     

重组结缔组织生长因子对体外培养成骨细胞核结合因子α1基因表达的影响

目的:研究发现,结缔组织生长因子可促进软骨细胞和成骨细胞的增殖及其表型的发生,在骨骼发育以及骨量维持方面发挥重要作用,但其对成骨细胞的作用机制目前尚不清楚。观察重组结缔组织生长因子对体外培养人成骨细胞核结合因子α1基因表达的影响。方法:实验于2006-01/2007-01在日照市人民医院完成。①实验材料:外科手术取正常成人髂骨松质骨,患者对试验知情同意。②实验方法:体外培养正常人成骨细胞,用不同浓度0,50,100,200,1000μg/L的重组结缔组织生长因子(0μg/L作为空白对照组)干预48h后,抽提细胞总RNA和总蛋白。③实验评估:采用半定量反转录-聚合酶链反应和蛋白免疫印迹分析方法观察不同浓度重组结缔组织生长因子对体外培养人成骨细胞核结合因子α1基因表达的影响。结果:半定量反转录-聚合酶链反应和蛋白免疫印迹结果显示,50,100,200,1000μg/L重组结缔组织生长因子干预后均可显著上调成骨细胞核结合因子α1的表达,并呈明显剂量依赖关系,与空白对照组比较,差异显著(P<0.01)。结论:重组结缔组织生长因子可剂量依赖性上调成骨细胞核结合因子α1基因的表达,核结合因子α1可能参与了结缔组织生长因子对成骨细胞增殖和分化的调节。     

Characteristics of dimeric (bis) bidentate selective high affinity ligands as HLA-DR10 beta antibody mimics targeting non-Hodgkin's lymphoma

Despite their large size, antibodies have proven to be suitable radioisotope carriers to deliver systemic radiotherapy, often molecular image-based, for lymphoma and leukemia. To mimic antibody (Ab) targeting behavior while decreasing size by 50-100x, a combination of computational and experimental methods were used to generate molecules that bind to unique sites within the HLA-DR epitopic region of Lym-1, an Ab shown effective in patients. Lym-1 Ab mimics (synthetic high afinity ligands; SHALs) were generated and studied in vitro, using live cell binding assays, and/or pharmacokinetic studies over 24 h in xenografted mice given 1 or 20 microg SHAL doses i.v. Multimilligram amounts of each of the dimeric (bis) SHALs were synthesized at high purity, and labeled with indium-111 at high specific activity and purity. These SHALs were selective for HLA-DR and HLA-DR expressing malignant cells and had functional affinities that ranged from 10(-9) M (nanomolar) to 10(-10) M. Blood clearances ranged from 3.6 to 9.5 h and body clearances ranged from 15.2 to 43.0 h for the 6 bis DOTA-SHALs studied in a mouse model for non-Hodgkin's lymphoma (NHL). While localization was shown in Raji NHL xenografts, biodistribution was influenced by 'sinks' for individual ligands of the SHALs. Highly pure, dimeric mimics for HLA-DR Ab were synthesized, biotinylated and radiolabeled, and showed selectivity in vitro. Pharmacokinetic behavior in mice was influenced by the ligands and by the linker length of the dimeric SHALs. Nanomolar or better functional affinity was observed when a suitably long linker was used to connect the two bidentate SHALs. The concept and methodology are of interest because applicable for targeting most proteins; the SHAL synthetic platform is highly efficient and adaptive.     

Recombinant expression of the beta-subunit of HLA-DR10 for the selection of novel lymphoma targeting molecules

Selective high-affinity ligands (SHALs) were selected as substitutes for monoclonal antibodies (mAbs) to deliver radioisotopes to malignant tumors. Because a SHAL (5 KD) is considerably smaller in comparison to an antibody (150 KD), a significant therapeutic index (TI) enhancement for radioimmunotherapy (RIT) is anticipated. The antibody-antigen (Ab-Ag) model system chosen for the development of SHALs consists of Lym-1, a MAb with proven selectivity in non-Hodgkin's lymphoma (NHL) patients and its well-characterized Ag, the beta subunit of HLA DR10. Whereas Lym-1 is readily available, the subunit of HLA-DR10 is not. Native, heterodimeric (alpha and beta subunits) HLA-DR10 can be purified from Raji cells, which are known to overexpress this Ag. Inconsistent homogeneity between preparations of HLA-DR10 solubilized in the presence of detergents prompted us to express a recombinant form of the beta subunit of HLA-DR10 in Escherichia coli. Negligible production yields (相似文献