Subcellular distribution of sulfated glucuronyl glycolipids in human peripheral motor and sensory nerves

Sulfated glucuronyl glycolipids (SGGL) have been implicated as important target antigens in patients with demyelinating polyneuropathy and IgM paraproteinemia. Sulfated glucuronyl paragloboside (SGPG), a major species of SGGL, was identified in the subcellular fractions of human peripheral motor and sensory nerves using a simple and quantitative method. SGPG was found to be concentrated in the myelin-enriched fractions of both motor and sensory nerves (1.3±0.3 and 1.5±0.4 µg/mg protein, respectively), whereas its concentration was 0.9±0.2 and 1.8±0.6 µg/mg protein in the axolemma-enriched fractions of motor and sensory nerves, respectively. Our finding that SGPG is more abundant in the human sensory nerve axolemma-enriched fraction may account for the clinical and pathological observations that the lesions are more heavily concentrated in the sensory nerve than in other parts of the nerve tissues in this disorder.     

念珠菌特异性IgM和IgG抗体在肺念珠菌病中的诊断价值

目的:评价念珠菌特异性IgM和IgG抗体在肺念珠菌病中的诊断价值。方法:入选2017-09-01～2018-03-31住院患者76例,其中临床诊断肺念珠菌病患者8例、拟诊诊断肺念珠菌病患者13例、非念珠菌病患者55例(曲霉菌病患者12例、非真菌病患者28例、未确定病原菌患者15例);用胶体金法念珠菌特异性IgM和IgG抗体检测患者血液标本,与血清G实验和肺泡灌洗液(BALF)G实验比较,分析IgM和IgG抗体检测在诊断肺念珠菌病中的价值。结果:76例患者全部行IgM和IgG抗体检测,IgM抗体检测阳性33例,IgG抗体检测阳性22例;38例患者行血清G实验检测,阳性1例;35例患者行BALF G实验检测,阳性15例。检测灵敏度、特异度和Youden指数,IgM抗体检测分别为100.0%、64.2%和0.642,IgG抗体检测分别为87.5%、77.9%和0.654,血清G实验分别为0%、97.1%和-0.029,BALF G实验分别为83.3%、65.4%和0.487。结论:IgM抗体检测诊断肺念珠菌病的灵敏度高,可作为高危患者的筛查指标;IgG抗体检测灵敏度和特异度均较高,可作为诊断肺念珠菌病的指标。     

Multi-isotype Glycoproteomic Characterization of Serum Antibody Heavy Chains Reveals Isotype- and Subclass-Specific N-Glycosylation Profiles

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Highlights

• •nLC-MS/MS method to analyze immunoglobulin (Ig) N-glycopeptides from human serum.
• •Multi-isotype, site-specific characterization of immunoglobulin N-glycosylation.
• •IgA2 sequence and glycosylation-site variant analyses.
• •Platform to define disease-specific N-glycan signatures for different Ig isotypes.

     

Detection of IgG and IgM to meningococcal outer membrane proteins in relation to carriage of Neisseria meningitidis or Neisseria lactamica

Carriage of non-serogroupable Neisseria meningitidis or Neisseria lactamica induces antibodies protective against meningococcal disease. Antibodies directed against outer membrane proteins are bactericidal and the serotype and subtype outer membrane protein antigens are being examined for their value as vaccine candidates for serogroup B disease. The aim of this study was to examine the effect of carriage of these two Neisseria species among children and young adults on induction of antibodies to outer membrane components from strains causing disease in Greece. Among 53 patients with meningococcal disease, IgG or IgM antibodies were detected by ELISA in 9 of 13 (69%) from whom the bacteria were isolated and 27 of 40 (67%) who were culture-negative. For military recruits (n = 604), the proportion of carriers of meningococci with IgM or IgG to outer membrane proteins was higher than non-carriers, P < 0.05 and P = 0.000000, respectively. Among school children (n = 319), the proportion with IgM or IgG to outer membrane proteins for carriers of meningococci was higher compared with non-carriers, P = 0.000000 and P = 0000043, respectively. Carriage of N. lactamica was not associated with the presence of either IgM or IgG to the outer membrane proteins in the children. The higher proportion of children (50%) with IgM to outer membrane proteins compared with recruits (10%) might reflect more recent exposure and primary immune responses to the bacteria. The lack of association between antibodies to outer membrane proteins and carriage of N. lactamica could reflect observations that the majority of N. lactamica isolates from Greece and other countries do not react with monoclonal typing reagents. Bactericidal antibodies to meningococci associated with high levels of IgG to N. lactamica were found in a previous study; these are thought to be directed to antigens other than outer membrane proteins or capsules and imply antigens such as lipo-oligosaccharide are involved in induction of antibodies cross-reactive with meningococci.     

丙肝病毒IgM抗体检测方法的初步研究

选择东燃公司的重组结构区和非结构区抗原建立的抗ＨＣＶ－ＩｇＭ检测方法,简便、快速、特异性强、重复性好、敏感性高。只在丙肝病人组检出而健康献血员均为阴性,与抗ＨＡＶ、ＨＢＶ的ＩｇＭ抗体无交叉反应,且排除了ＲＦ干扰和ＩｇＧ占位引起的假阳性和假阴性,适用于抗ＨＣＶ－ＩｇＭ的临床检测。对２４例丙肝病人的抗ＨＣＶ－ＩｇＭ检测结果显示,急性丙肝病人血清抗ＨＣＶ－ＩｇＭ检出率较高（７５％,６／８）,且随ＡＬＴ正常而消失或滴度下降。慢性病人抗ＨＣＶ－ＩｇＭ检出率为５６．３％（９／１６）,其中７例ＩｇＭ持续阳性者为慢性活动性丙肝,说明慢性病人抗ＨＣＶ－ＩｇＭ与疾病的活动性密切相关。结果提示抗ＨＣＶ－ＩｇＭ的检测在急性肝炎的诊断及慢性丙肝的预后和转归上具有临床意义。     

哈尔滨地区发热患者风疹病毒的分离鉴定

目的 为了明确哈尔滨地区风疹病毒（Rubella virus,RV）的流行情况,对2003年上半年采集的部分发热患者血清及血细胞进行筛选、鉴定、比较,进行血清学和病原学研究。同时从风疹病毒IgM抗体阳性患者血中分离病毒,对疑似风疹病毒的分离株进行鉴定。方法 采用酶联免疫吸附试验（ELISA）对159例发热患者血清中的风疹病毒IgM进行测定;采用BHK21细胞培养法对风疹病毒IgM抗体阳性患者血标本进行风疹病毒分离,并用RT—PCR、细胞生长曲线、电镜观察、免疫组化等方法对可疑风疹病毒株进行鉴定。结果 风疹病毒IgM抗体阳性为22例,占13．83％;经RT—PCR、细胞生长曲线、电镜观察、免疫组化等方法初步鉴定从血液标本中获得的病毒分离株是风疹病毒。结论 采用FTISA决对该地区159例发热患者血清风疹病毒IgM进行检测,阳性率为13．83％;获得了1株风疹病毒分离株。     

严重急性呼吸综合征(SARS)病人血清抗体水平的初步探讨

为了了解严重急性呼吸综合征(SARS)病人血清中的抗体产生规律,对56份病人血清和36份健康人血清,分别采用间接酶联免疫吸附试验(EIA)检测IgG抗体和捕获法检测IgM抗体。结果显示：56份病人血清中有48份IgG抗体阳性,7份IgM抗体阳性。     

Increased antigen binding strengths of hybrid antibodies produced by human hybrid hybridomas

Two cell lines of human hybridomas were fused to generate hybrid antibodies. One human hybridoma cell line was HT2 producing IgM monoclonal antibody (MAb) reactive to carboxy peptidase A (Cpase) and double stranded DNA (ds DNA) and another was SU-1-D2 secreting IgM MAb reactive to ds DNA but not to Cpase. Most hybrid hybridomas obtained by fusion of the two hybridomas secreted hybrid antibodies exhibiting increased antigen binding strengths. All of the hybrid antibodies with increased binding strengths against Cpase and ds DNA contained only the light chains derived from SU-1-D2. These results suggested that increase in the binding strength of the hybrid antibodies resulted from heterogeneous association of H and L chains derived from HT2 and SU-1-D2 cells.     

IgM memory and Waldenstr?m macroglobulinemia’s cell of origin

Waldenström macroglobulinemia (WM) is a neoplasm of mature IgM-expressing B-lymphocytes that is characterized by the occurrence of a monoclonal IgM (mIgM) paraprotein in blood serum and the infiltration of hematopoietic bone marrow with malignant lymphoplasmacytic cells. WM remains incurable despite the development of new therapeutic options. Owing in large measure to having a low incidence, indolent clinical course and good long-term control with proper clinical management, WM has not been investigated as extensively as other B-lineage neoplasms. Major knowledge gaps in our understanding of the natural history of WM include the cell of origin. With that shortcoming in mind, here we discuss the significance of a specific gain-of-function mutation in the adapter protein, myeloid differentiation primary response 88 (MYD88), that occurs with near-complete penetrance in WM and suggests that tumor development is under strong selective pressure for elevated MYD88 signaling. This provides an intriguing link to IgM memory B-cells, which comprise two types of B-lymphocytes ( natural effector IgM⁺IgD⁺ cells and IgM^-only IgM⁺IgD^- cells ) that depend, in part, on MYD88 signaling and constitute intriguing candidates for WM’s cell of origin. We review the features and developmental history of IgM memory in greater depth and propose that WM may be derived from primitive innate-like B-cells ( marginal zone B-cells and B1 B-cells ) that feed the IgM memory compartment. We conclude with a model of MYD88-dependent tumor development in the mature B-cell lineage that considers two different ( convergent or divergent) oncogenesis pathways with respect to the cells of origin.