B cells as a target of immune modulation

B cells have recently been identified as an integral component of the immune system; they play a part in autoimmunity through antigen presentation, antibody secretion, and complement activation. Animal models of multiple sclerosis (MS) suggest that myelin destruction is partly mediated through B cell activation (and plasmablasts). MS patients with evidence of B cell involvement, as compared to those without, tend to have a worse prognosis. Finally, the significant decrease in new gadolinium-enhancing lesions, new T2 lesions, and relapses in MS patients treated with rituximab (a monoclonal antibody against CD20 on B cells) leads us to the conclusion that B cells play an important role in MS and that immune modulation of these cells may ameliorate the disease. This article will explore the role of B cells in MS and the rationale for the development of B cell–targeted therapeutics. MS is an immune-mediated disease that affects over 2 million people worldwide and is the number one cause of disability in young patients. Most therapeutic targets have focused on T cells; however, recently, the focus has shifted to the role of B cells in the pathogenesis of MS and the potential of B cells as a therapeutic target.     

Novel azapeptide inhibitors of cathepsins B and K. Structural background to increased specificity for cathepsin B

Abstract: We have designed and synthesized a new series of azapeptides which act as potential inhibitors of cathepsin B and/or cathepsin K. Their structures are based upon the inhibitory sites of natural cysteine protease inhibitors, cystatins. For the synthesized azapeptides, the equilibrium constants for dissociation of inhibitor–enzyme complex, K_i, were determined. Comparison of these values indicated that all of the azainhibitors act much stronger toward cathepsin B. Z‐Arg‐Leu‐His‐Agly‐Ile‐Val‐OMe ( 7 ) proved to be approximately 500 times more potent for cathepsin B than for cathepsin K. To be able to explain the obtained experimental values we used the molecular dynamics procedures to analyze the interactions between cathepsin B and compound 7 . We also determined the structure of the most potent and selective cathepsin B azainhibitor by means of NMR studies and theoretical calculations. In this report, we describe SAR studies of azapeptide inhibitors indicating the influence of the conformational flexibility of the examined compounds on inhibition of cathepsins B and K.     

Immune reactivity towards insulin, its amyloid and protein S100B in blood sera of Parkinson's disease patients

Peripheral immune responses can be sensitive indicators of disease pathology. We evaluated the autoimmune reactions to endocrine (insulin) and astrocytical (S100B) biomarkers in the blood sera of 26 Parkinson's disease (PD) patients compared with controls by using ELISA. We found a statistically significant increase of the autoimmune responses to both antigens in PD patients compared with controls with a mean increase of 70% and 50% in the autoimmune reactions towards insulin and S100B, respectively. Heterogeneity of the immune responses observed in patients may reflect the modulating effect of multiple variables associated with neurodegeneration and also changes in the basic mechanisms of individual autoimmune reactivity. We did not detect any pronounced immune reactions towards insulin amyloid fibrils and oligomers in PD patients, indicating that an amyloid-specific conformational epitope is not involved in immune recognition of this amyloid type, while sequential epitope of native insulin is hidden within the amyloid structures. Immune reactions towards S100B and insulin may reflect the neurodegenerative brain damaging processes and impaired insulin homeostasis occurring in PD.     

复方丹参注射液干扰素治疗乙肝后肝纤维化

目的探讨复方丹参注射液联合干扰素治疗慢性乙肝患者的疗效。方法110例慢性乙肝患者，按随机方法分成①对照组30例，应用普通保肝药物治疗，疗程6个月；②丹参组30例，应用复方丹参注射液（每ml含丹参、降香各1g）30ml加入10％葡萄糖溶液300ml中静脉注射1个月；③IFN组30例，应用IFN—α 3MU，隔日一次肌内注射，3个月；④联合组20例，应用复方丹参注射液30ml加10％葡萄糖溶液300ml静脉注射1个月，IFN-α 3MU，隔日一次肌内注射，3个月。丹参组，IFN组和联合组保肝药物治疗同对照组。四组病例在性别、年龄、病程，治疗前肝功能等方面均无统计学差异。治疗前检测肝功能，肝炎病毒标志，血清HA、IV—C、PCI—Ⅱ，部分病例进行肝穿病理检查。治疗开始后每月检测肝功能，3个月（治疗后）和6个月（随访时）时检测血清HA、IV—C、PCⅢ及乙肝病毒标志，治疗后1年行肝穿病理检查。结果治疗前四组患者血清HA、PCⅢ、IV—C水平无统计学差异；治疗后丹参组、IFN组、联合组血清HA、FCⅢ、IV—C水平较治疗前及对照组有不同程度的降低。结论复方丹参注射液联合IFN治疗可使血清HA、PCⅢ、IV—C有明显下降，肝组织病理改变明显改善，为目前有效的慢性乙肝治疗措施。     

近视性屈光参差的功能性磁共振成像研究

目的利用血氧水平依赖性功能性磁共振成像(BOLD-fMR I)技术,探索人类近视性屈光参差是否对大脑皮层功能和结构造成影响。方法采用无磁MR I专用眼镜纠正屈光不正,以1.5T磁共振成像系统采集8例近视性屈光参差者枕叶视皮层兴趣区BOLD-fMR I数据,比较双眼皮层激活部位及范围的不同,及视力较差眼屈光纠正前后皮层激活情况的变化,分析其改变特点及机制。结果矫正屈光基础上,近视性屈光参差者双眼激活范围没有明显差异(P>0.05);视力较差眼屈光矫正前后皮层激活范围有明显差异(P<0.05)。结论人类近视性屈光参差可能没有发生明显的皮层功能损害及优势眼的转移;配镜可明显提高视力较差眼的皮层激活,应尽早配镜或手术矫正。     

Bile-pancreatic juice exclusion promotes Akt/NF-kB activation and chemokine production in ligation-induced acute pancreatitis

Using a unique surgical model (the donor rat model), we showed previously that duodenal replacement of bile-pancreatic juice, obtained fresh from a donor rat, ameliorates ligation-induced acute pancreatitis. We hypothesize that bile-pancreatic juice exclusion from gut exacerbates Akt/nuclear factor-kB (NF-kB) pathway activation and induces chemokine production in ligation-induced acute pancreatitis. We compared rats with bile-pancreatic duct ligation to those with duodenal bile-pancreatic juice replacement fresh from a donor rat beginning immediately before duct ligation. Sham control rats had ducts dissected but not ligated. Rats were killed 1 or 3 hours after operation (n=7/group). Akt activation (immunoblotting, immune-complex kinase assay, and ELISA), inhibitory protein I-kB (I-kB) activation (immunoblotting), and production of chemokines MCP-1 and RANTES (ELISA) were measured in pancreatic homogenates. NF-kB was quantitated in nuclear fractions using electrophoretic mobility shift assay. Duct ligation produced significant increases in pancreatic Akt, IkB, and NF-kB activation and production of MCP-1 and RANTES. Activation of the Akt/NF-kB pathway and increased MCP-1 and RANTES production in response to duct ligation were significantly reduced by bile-pancreatic juice replacement (ANOVA, P<0.05). Bile-pancreatic juice exclusion stimulates Akt/NF-kB pathway activation and increases chemokine production in ligation-induced acute pancreatitis. Presented at the annual meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 16, 2005 (poster).     

Immunogenicity and safety of a novel yeast Hansenula polymorpha-derived recombinant Hepatitis B candidate vaccine in healthy adolescents and adults aged 10–45 years

The aim was to determine whether the immunogenicity of an investigational hepatitis B vaccine (spHB) is at least as high as that of a licensed control vaccine, Engerix B^®, and to evaluate its safety before inclusion in new pediatric combination vaccines. Two randomized, controlled, blind-observer, Phase 3 trials were performed: one in Argentina (344 participants aged 10–15 years, 10 μg HBsAg/dose) and one in Uruguay (344 participants aged 16–45 years, 20 μg HBsAg/dose). Both vaccines were given in a 0, 1, 6 month schedule to all participants with a baseline anti-Hep B antibody titer <0.6 mIU/mL. Antibody titers were measured pre-dose 1, 1 month after dose 2, pre-dose 3, and 1 month after dose 3. Statistical non-inferiority analyses were performed on seroprotection rates (SP) post-dose 3 (% with anti-Hep B titers ≥10 mIU/mL; delta non-inferiority limit of −10%). In both studies, SP for the spHB vaccine was 100% and the spHB vaccine was non-inferior in terms of SP to the licensed control vaccine. GMTs post-dose 3 were approximately 1.8- and 4.1-fold higher for spHB in the 10–15 year and 16–45 year age groups, respectively. Reactogenicity was low for each vaccine, after each dose. This highly immunogenic hepatitis B candidate vaccine was selected for further investigation as a component of new pediatric combination vaccines.     

丙泊酚对大鼠缺血再灌注肾NF-κB、TNF-α表达的影响

目的 研究丙泊酚对大鼠肢体缺血再灌注损伤后肾组织中肿瘤坏死因子-α（tumornecrosisfactor-α，TNF-α）、核因子-κB（nuclear factor-κxB，NF-κB）表达的影响。方法 24只SD雄性大鼠，随机分为假手术对照组（A组），肢体缺血再灌注组（B组）和丙泊酚干预组（C组），每组8只。采用免疫组织化学方法检测TNF-α、NF-κB的表达，行图像分析半定量。结果 B组大鼠肾组织中TNF-α、NF-κB的表达明显高于A组（P〈0．05），C组明显低于B组（P〈0．05）。结论 肢体缺血再灌注后有明显肾损伤，丙泊酚对肢体缺血再灌注肾损伤有一定程度的保护作用，其机制可能与下调大鼠肢体缺血再灌注损伤肾组织中TNF-α、NF-κB的过度表达有关。