Detection of antibodies specific for sheeppox and goatpox viruses using recombinant capripoxvirus antigens in an indirect enzyme-linked immunosorbent assay

Viruses in the genus Capripoxvirus, family Poxviridae, cause sheeppox, goatpox and lumpy skin disease, which are the most serious poxvirus diseases of production animals. Despite the considerable threat that these viruses pose to livestock production and global trade in sheep, goats, cattle and their products, convenient and effective serodiagnostic tools are not readily available. To develop a more effective antibody detection capability, selected open reading frames from capripoxvirus DNA were amplified and expressed in Escherichia coli as His-tagged fusion proteins. By screening 42 candidate antigens, two sheeppox virus virion core proteins that were expressed efficiently, purified readily using affinity chromatography and reactive against capripoxvirus immune sera in an indirect enzyme-linked immunosorbent assay (ELISA) were identified. The ELISA performed favourably when sera from sheep and goats infected experimentally with virulent capripoxvirus isolates were tested, with sensitivity and diagnostic specificity ranging between 95 and 97%, but it was unable to detect antibodies reliably in vaccinated sheep or goats. Furthermore, no cross-reactivity with antibodies against orf virus was detected. This assay offers the prospect of a convenient and standardised ELISA-based serodiagnostic test, with no requirement for infectious reagents, that is well suited to high-throughput capripoxvirus surveillance on a flock or herd basis.     

Seroprevalence of influenza A and B in German infants and adolescents

The objective of this study was to provide seroepidemiological information on influenza A and B antibodies in children and adolescents. Viral immunoglobulin G antibodies were determined retrospectively using enzyme-linked immunosorbent assays in a group of 1,111 children and adolescents. Sera (809) from healthy adult blood donors served as controls. In children, the prevalence of antibodies against influenza A was 82.0% and against influenza B 9.6%, whereas in adults the prevalence of antibodies against influenza A was calculated as 99.4% and against influenza B 56.7%. After decline of maternal antibodies during the first year of life, there was an increase of prevalence of influenza A antibodies up to 100% by the age of 12 years. In contrast, only 1–2% of children up to 9 years had influenza B antibodies increasing to 25% by the age of 18 years and to 70% among adults aged 30 years. Children aged 0–6 years had significantly lower concentrations and >12–15-year-old adolescents had significantly higher concentrations of antibodies against influenza A than adults. For all age groups of children and adolescents, significantly lower antibody concentrations against influenza B were measured in comparison to the blood donor control group. In conclusion, the annual influenza vaccination in children and adolescents may improve considerably the protection against influenza virus infection occurring during epidemics.     

Fine specificity and sequence of antibodies directed against the ectodomain of matrix protein 2 of influenza A virus

The ectodomain of matrix protein 2 (M2e) has remained remarkably conserved amongst human influenza A viruses and is a target for Abs with protective activity. For these reasons, M2e is being investigated for its potential as a broadly protective influenza A virus vaccine. Here, we report on the fine specificity and sequence of seven M2e-specific mAbs isolated from three BALB/c mice after different immunization protocols. The mAbs recognized epitopes comprised within a 13 aa long peptide corresponding to M2e(4-16). They originated from 4 distinct precursor B cells and showed a highly restricted variable (V) gene usage, in that their heavy chain V regions were all formed by the same V_H, D and J_H gene segments and their light chain V regions made use of only two distinct Vκ genes (Vκ19-15/IGKV6-15 and Vκ8-30/IGKV8-30; NCBI/IMGT annotation, respectively). The consensus sequence of the expressed V_H genes belongs to the J558/HV1 family. It showed 96% identity with the BALB/c germline gene J558.n/IGHV1S137 and 100% identity with a V_H gene expressed by several BALB/c B-1 B cells. This suggests that the consensus sequence is that of a functional BALB/c germline V_H gene. The genetic restriction of this response may in part underlie the generally poor M2e-specific Ab response induced by infection.     

Activating and inhibitory FcgammaRs in autoimmune disorders

Autoimmune disorders are characterized by the destruction of self-tissues by the immune system. Multiple checkpoints are in place to prevent autoreactivity under normal circumstances. Coexpression of activating and inhibitory Fc receptors (FcR) represents such a checkpoint by establishing a threshold for immune cell activation. In many human autoimmune diseases, however, balanced FcR expression is disturbed. Analysis of murine model systems provides strong evidence that aberrant FcR expression can result in uncontrolled immune responses and the initiation of autoimmune disease. This review will summarize this data and explain how this information might be used to better understand human autoimmune diseases and to develop novel therapeutic strategies.     

Kisspeptin immunoreactive cells of the ovine preoptic area and arcuate nucleus co-express estrogen receptor alpha

Kisspeptins are peptide ligands of the G protein-coupled receptor GPR54, recently shown to be essential to reproductive function. We have raised specific rabbit antisera against a highly conserved 10 amino acid-amidated peptide (kp10) common to all kisspeptin isoforms isolated so far and mapped the distribution of kp10-immunoreactive (ir) cells in the ovine hypothalamus. Kp10-ir cells were predominant in the caudal arcuate nucleus, the dorsomedial nucleus and the medial preoptic area. Numerous varicose kp10-ir fibers were found in the preoptic area where GnRH neurons reside and in the median eminence, seemingly projecting around small capillaries in its external zone. Within the caudal arcuate nucleus, nearly all kp10-ir cells showed an intense estradiol receptor alpha immunofluorescent signal compared with approximately half of kp10-ir cells in the preoptic area. The pattern of distribution of kp10 immunoreactivity in the hypothalamus suggests a role for kisspeptin in the estrogen-dependent regulation of GnRH and LH secretion in the ewe.     

Elevation of oxidized DJ-1 in the brain and erythrocytes of Parkinson disease model animals

DJ-1, the causative gene of a familial form of Parkinson's disease (PD), has been reported undergo oxidation preferentially at the 106th cysteine residue (Cys-106) under oxidative stress. Recently, it has been found that the levels of oxidized DJ-1 in erythrocytes of unmedicated PD patients are markedly higher than those in medicated PD patients and healthy subjects. In the present study, we examined the changes in oxidized DJ-1 levels in the brain and erythrocytes of PD animal models using specific antibodies against Cys-106-oxidized DJ-1. Treatment with PD model compounds such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 6-hydroxydopamine significantly elevated the levels of oxidized DJ-1 in erythrocytes. Immunohistochemical analysis also revealed that the number of oxidized DJ-1 antibody-positive cells in the substantia nigra of MPTP-treated mouse increased in a dose-dependent manner. These results suggest that the oxidative modification of DJ-1 in the brain and erythrocytes is involved in the pathogenesis of PD in animal models.     

Virus neutralising activity of African fruit bat (Eidolon helvum) sera against emerging lyssaviruses

It is likely that phylogroup 2 lyssaviruses circulate within bat reservoirs. We adapted a pseudotype (pt) neutralisation assay (PNA) to a multiplex format enabling serosurveillance for Lagos bat virus (LBV), Mokola virus (MOKV) and West Caucasian bat virus (WCBV) in a potential reservoir, the African straw-coloured fruit bat, Eidolon helvum. Highly correlated titres were observed between single and multiplex PNAs using ptLBV and ptMOKV (r = 0.97, p < 0.0001), validating its use for bat serosurveillance. Of the bat serum samples screened 56% neutralised ptLBV, 27% ptMOKV and 1% ptWCBV. Mean VNAb titres were 1:266, 1:35 and 1:7 against ptLBV, ptMOKV and ptWCBV respectively. The high seroprevalence estimates suggest that the infection rate of LBV in E. helvum remains high enough to persist in this species. This supports the hypothesis that LBV is endemic in Ghanaian E. helvum and we speculate that LBV may have co-evolved with African megachiroptera.     

新入伍人群单纯疱疹病毒Ⅰ型血清抗体检测分析

目的了解入伍新兵人群中单纯疱疹病毒Ⅰ型(HSV-Ⅰ)感染IgG抗体的流行分布,为预防提供科学依据。方法利用酶联免疫吸附试验(ELISA)对本区近4年来自8个省市的360名入伍新兵血清进行HSV-ⅠIgG抗体检测。结果2002,2004,2006,2008年各年入伍新兵血清HSV-ⅠIgG抗体阳性率呈下降趋势,分别为90.00%,86.67%,85.55%,84.44%,平均86.67%;地区间差别明显,广西(96.00%)和江苏(92.98%)较高,甘肃(74.42%)和湖北(78.13%)较低;入伍前工作与否者的抗体阳性检出率差异无统计学意义。结论入伍新兵人群中HSV-Ⅰ感染水平较高,呈逐年降低趋势并有非常显著性地区差异;新兵入伍期间,应采取健康教育等有效预防措施,降低人群HSV-Ⅰ感染水平。     

1型糖尿病免疫诊断标志物的研究进展

1型糖尿病是由胰岛β细胞自身免疫性破坏引起的一种代谢性疾病.患者体内存在多种针对胰岛细胞自身抗原的自身抗体,成为1型糖尿病的免疫诊断标记物.临床目前最为常用的是胰岛细胞抗体(ICA)、胰岛素自身抗体(IAA)、谷氨酸脱羧酶抗体(GADA)和胰岛细胞瘤相关蛋白(IA)-2抗体,此外,新近发现ZnT8A和胰岛特异性的葡萄糖-6-磷酸酶催化亚基相关蛋白抗体(IG-RPA)可能在诊断上也具有重要的价值.多种自身抗体的组合诊断具有更高的特异性和敏感性.本文针对国内外对1型糖尿病免疫诊断标记物的研究进展情况,详细分析了多种免疫诊断标志抗原的哪功能、特性及在诊断方面的意义和应用.     

IgG subclasses pattern and high-avidity antibody to the C-terminal region of merozoite surface protein 1 of Plasmodium vivax in an unstable hypoendemic region in Iran

The C-terminal region of Plasmodium vivax merozoite surface protein 1 (PvMSP-1₁₉) is a leading vaccine candidate for inclusion in a polyvalent malaria vaccine. In the present study, the IgG subclasses profile and the avidity of IgG to PvMSP-1₁₉ were evaluated in individuals (n = 94) naturally exposed to P. vivax parasite in malaria endemic areas in Chabahar districts, Iran. In individuals with patent P. vivax malaria, 86.1% was sero-positive to PvMSP-1₁₉ and IgG1 (81.9%) was the predominant subclass. In addition, to determine the persistence of specific IgG, IgG1 and IgG3 antibodies to PvMSP-1₁₉, the frequency of antibodies was determined in the infected subjects (n = 74) after treatment with standard chloroquine and it was detected that the frequency of responders was significantly reduced to 51.3%, 51% and 16.2%, respectively. The antigen-binding avidity of IgG antibodies to PvMSP-1₁₉ was measured in sero-positive sera and the high-avidity of IgG, IgG1 and IgG3 was found in 66.6%, 61% and 47% of the infected subjects with P. vivax, respectively. The present result shows that individuals who exposed to vivax malaria in the endemic region in Iran develop antibodies with high-avidity to PvMSP-1₁₉. These results could help to understand the interactions between the host and P. vivax parasite in development of MSP-1₁₉-based vaccine.