Anti-amyloid beta protein antibody passage across the blood-brain barrier in the SAMP8 mouse model of Alzheimer's disease: an age-related selective uptake with reversal of learning impairment

Amyloid beta protein (Abeta) levels are elevated in the brain of Alzheimer's disease patients. Anti-Abeta antibodies can reverse the histologic and cognitive impairments in mice which overexpress Abeta. Passive immunization appears safer than vaccination and treatment of patients will likely require human rather than xenogenic antibodies. Effective treatment will likely require antibody to cross the blood-brain barrier (BBB). Unfortunately, antibodies typically cross the BBB very poorly and accumulate less well in brain than even albumin, a substance nearly totally excluded from the brain. We compared the ability of two anti-Abeta human monoclonal IgM antibodies, L11.3 and HyL5, to cross the BBB of young CD-1 mice to that of young and aged SAMP8 mice. The SAMP8 mouse has a spontaneous mutation that induces an age-related, Abeta-dependent cognitive deficit. There was preferential uptake of intravenously administered L11.3 in comparison to HyL5, albumin, and a control human monoclonal IgM (RF), especially by hippocampus and olfactory bulb in aged SAMP8 mice. Injection of L11.3 into the brains of aged SAMP8 mice reversed both learning and memory impairments in aged SAMP8 mice, whereas IgG and IgM controls were ineffective. Pharmacokinetic analysis predicted that an intravenous dose 1000 times higher than the brain injection dose would reverse cognitive impairments. This predicted intravenous dose reversed the impairment in learning, but not memory, in aged SAMP8 mice. In conclusion, an IgM antibody was produced that crosses the BBB to reverse cognitive impairment in a murine model of Alzheimer's disease.     

冠心病与巨细胞病毒初期感染的相关性研究

目的探讨人类巨细胞病毒初期感染与冠心病发生发展的关系。方法用捕获ELISA法检测血清HCMV—IgM,酶法检测血脂4项,免疫比浊法检测C-反应蛋白（CRP）,并进行比较。结果冠心病组（61例）、健康对照组（44例）和其他疾病组（48例）的HCMV—IgM阳性率分别为8．20％、2．27％和4．17％,冠心病组与对照组之间无统计学差异（P〉0．05）;冠心病组血脂4项和CRP均高于健康对照组,有统计学差异（P〈0．05）。结论尚不能认为冠心病与巨细胞病毒初期感染有关。     

1491例孕妇血清中抗弓形虫抗体IgG、IgM的检测结果分析

目的了解昆山市孕妇弓形虫感染情况。方法采用ELISA法对1491例孕妇的血清进行TOX—IgG、IgM检测。结果TOX抗体总阳性率791％,其中IgG（＋）92例,占6.17％;IgM（＋）为23例,占154％;IgG、IgM均阳性者5例,占034％;有动物接触史的孕妇弓形虫感染率高于无动物接触史的孕妇（p〈0.05）;有不良妊娠史的孕妇弓形虫感染率高于无不良妊娠史的孕妇（P〈0.05）。结论孕期妇女应注意日常卫生,改变不良生活习惯,避免不良妊娠结局的发生。     

深圳市福田区2006～2007年麻疹疑似病例血清学检测分析

目的了解麻疹流行特点,加速麻疹控制,完善今后麻疹监测工作。方法对2006～2007年福田区麻疹疑似病例进行血清学检测分析。结果2007年麻疹发病率较2006年呈上升趋势,青壮年（16～35岁）是成人麻疹高发人群。样品采集时间对检测结果有影响,出疹后1d内采血样品阳性率最低。结论麻疹发病率有上升趋势,5岁及以下儿童及青壮年是麻疹防控重点人群。麻疹血样注意避免出疹后1d内采集。     

南昌市2007年麻疹疑似病例麻疹IgM抗体检测分析

目的了解南昌市2007年麻疹疑似病例IgM抗体阳性率及麻疹流行现状,为制定控制麻疹措施提供依据。方法采集麻疹疑似病例血清标本,用ELISA法检测麻疹IgM抗体,对其中麻疹IgM抗体阴性标本测定风疹IgM抗体,所得数据用SPSS软件分析。结果南昌市2007年122例麻疹疑似病例血清中,麻疹IgM抗体阳性率为42．6％;70份麻疹IgM阴性标本中,检出风疹IgM抗体阳性14例。麻疹发病主要集中在3-6月份;以5岁以下儿童为主,〈8月龄和〉15岁大年龄组阳性构成比较去年均有所增加。结论提高麻疹疫苗的常规免疫,重点加强大年龄组人群的强化免疫,在消除麻疹阶段应注意控制风疹的发病。     

Evaluation of the EIE-IgM-Leptospirose assay for the serodiagnosis of leptospirosis

Access to low-cost, effective diagnosis for leptospirosis is urgently needed in developing countries. The EIE-IgM-Leptospirose, a kit produced for public health laboratories in Brazil, was shown to have a sensitivity of 76% (77 of 102 patients) and 100% (102 of 102 patients) during acute and convalescent-phase leptospirosis, respectively, and a specificity of 93-100% (total healthy and patient control subjects evaluated, 486). These findings indicate that the assay will be useful for diagnosis of this emerging infectious disease in Brazil and other developing countries.     

Effect of the presence or absence of J chain on expression of recombinant anti-Kell immunoglobulin M

summary .  The aim of this study was to determine the effect of expressing a recombinant anti-Kell immunoglobulin (Ig) M from two cell lines, CH0 and NS0, on its ability to function as a diagnostic antibody. As a polymeric immunoglobulin, IgM is able to directly agglutinate red blood cells (RBCs), making it a useful blood grouping reagent. To simplify expression, recombinant human IgM (rIgM) from NS0 (a mouse myeloma line) and CHO (Chinese hamster ovary line) cells was expressed in the absence of human J chain. Whereas NS0 expresses mouse J chain, rIgM expressed from CH0 cells lack J chain. Although the ability to polymerize resides within the tailpiece of IgM heavy chain, J chain can influence the polymeric state. This in turn could affect the ability of rIgM to bind its antigen. The variable region of the heavy chain of an anti-Kell IgG was grafted onto the constant region of human IgM and co-expressed with light chain derived from the same antibody. rIgM was purified from each cell line and the strength of direct agglutination assessed. Both cell lines produced polymeric rIgM that was able to specifically bind the target antigen and to directly agglutinate RBCs to the same degree. The presence or absence of J chain did not affect the ability of the rIgM to bind the Kell antigen or the strength of agglutination. The presence of J chain is not required for the production of a functional rIgM for use as a diagnostic reagent. CHO and NS0 lines are both suitable for production of such a reagent.     

Antibodies to myelin-associated glycoprotein (anti-Mag) in IgM amyloidosis may influence expression of neuropathy in rare patients

We have examined whether antibodies to myelin-associated glycoprotein (anti-MAG) influence neuropathy occurrence and phenotype in primary (AL IgM) amyloidosis. Anti-MAG and the cross-reacted sulfoglucuronyl paragloboside antibodies (SGPG) were studied in 46 patients with IgM amyloidosis (21 with polyneuropathy), and 21 matched IgM MGUS (monoclonal gammopathies of undetermined significance) controls without neuropathy. We assessed the occurrence, phenotype of neuropathy, and attributes of nerve conduction and their relation to antibody activity. Twenty of 46 patients with IgM amyloidosis (7 with and 13 without polyneuropathy) had elevation of anti-MAG or SGPG by enzyme-linked immunosorbent assay (ELISA). Two of the polyneuropathy patients with IgM amyloidosis had antibodies to MAG based on Western blot (WB) positivity. One of these patients, with the highest anti-MAG titer, had a painful sensory ataxia, with prominent demyelination, and amyloid deposition in sural nerve. The other anti-MAG WB-positive amyloid patient had an axonal neuropathy and dysautonomia. Low levels of anti-MAG antibodies were found in 12 of 21 IgM MGUS controls without neuropathy (mean follow-up, 11 years). We conclude that finding serum anti-MAG antibodies does not exclude the diagnosis of primary amyloidosis. They do not appear to affect the occurrence or expression of polyneuropathy, except possibly in occasional cases with WB positivity.     

HCMV—IgM捕获ELISA法的建立及其应用

目的　建立检测人巨细胞病毒 (HCMV)抗原特异性 Ig M的酶联捕获技术 (Capturing- EL ISA)。方法　应用 Capturing- EL ISA法检测 12 8份巨细胞病毒感染者血清中抗 HCMV- Ig M,并与常用的间接 EL ISA法进行比较。结果　抗原浓度、抗 HCMV抗体酶结合物浓度对所测得的标本 OD值都有不同程度的影响 ,用最适的实验条件建立的 Cap-turing- EL ISA法特异性及敏感性均高于间接 EL ISA法 ,且不受 RF因子的影响。结论　 Capturing- EL ISA敏感性高、特异性强 ,且简便、快速 ,重复性好 ,具有实际应用价值