High activity of indoleamine 2,3-dioxygenase is associated with renal insufficiency in Puumala hantavirus induced nephropathia epidemica

Nephropathia epidemica (NE) is a hemorrhagic fever with renal syndrome caused by Puumala hantavirus. The severity of NE varies greatly. The aim of the present study was to evaluate whether serum indoleamine 2,3-dioxygenase (IDO) activity is associated with the severity of NE. A prospectively collected cohort of 102 consecutive patients with acute serologically confirmed NE was examined. Serum kynurenine, tryptophan, creatinine, CRP, and blood cell count were measured for up to 5 consecutive days after admission. The kynurenine to tryptophan (kyn/trp) ratio reflecting IDO activity was calculated. A maximum kyn/trp ratio >202 μmol/mmol had a sensitivity of 85% and a specificity of 75% for detecting maximum serum creatinine values >250 μmol/L by receiver operating characteristic (ROC) analysis. A maximum kyn/trp ratio >202 μmol/mmol (high IDO level) was also associated with other parameters reflecting the severity of the disease and renal impairment. Patients with high IDO levels had higher maximum serum creatinine (379 vs. 102 μmol/L, P<0.001), plasma C-reactive protein (104.1 vs. 72.1 mg/L, P=0.029), and blood leukocyte values (11.9 vs. 9.0 × 10(9) /L, P<0.001) compared to patients with kyn/trp ratio ≤ 202 μmol/mmol. They also had lower minimum urinary output (1,100 vs. 1,900 ml/day, P<0.001) and longer hospital stays (8 vs. 5 days, P<0.001). In conclusion, high serum IDO activity was associated with increased disease severity and renal impairment in NE.     

Evaluation of serological methods for diagnosis of Puumala hantavirus infection (nephropathia epidemica).

Nephropathia epidemica (NE), Puumala (PUU) virus infection, is a febrile disease which is commonly associated with acute renal impairment. To differentiate NE from other acute febrile illnesses, a rapid and reliable serological diagnosis is important, and a number of different protocols have recently been introduced. In the present report we describe a comparative evaluation of six PUU virus immunoglobulin M (IgM) and seven IgG enzyme-linked immunosorbent assay (ELISA) protocols based on native, Escherichia coli-expressed, or baculovirus-expressed nucleocapsid protein (N). Neutralization and immunofluorescence assays were included for comparison. Equally high sensitivities and specificities were obtained with three mu-capture-based IgM ELISAs using native, baculovirus-expressed, and E. coli-expressed N antigens, respectively, and by an ELISA based on purified E. coli-expressed full-length N adsorbed to solid phase. The assays based on truncated amino-terminal N proteins, including a commercially available PUU virus IgM ELISA, all showed lower sensitivities. For detection of PUU virus-specific IgG, ELISAs based on monoclonal antibody-captured native or baculovirus-expressed N antigens showed optimal sensitivities and specificities, while the assays based on E. coli-expressed N did not detect all PUU virus IgG-positive serum samples. A commercially available PUU virus IgG ELISA based on E. coli-expressed amino-terminal N showed a significantly lower sensitivity than those of all other IgG assays.     

Detection of nephropathia epidemica (Puumala virus)-specific immunoglobulin M by enzyme-linked immunosorbent assay.

Nephropathia epidemica (NE), a less severe form of hemorrhagic fever with renal syndrome, is caused by Puumala virus (PUU). This communication reports the development of a mu-capture enzyme-linked immunosorbent assay (ELISA) for detection of specific immunoglobulin M (IgM) antibodies to PUU virus in human sera. Acute- and early-convalescent-phase sera (collected 1 to 41 days after disease onset) from 29 Swedish patients with clinical NE were tested for PUU virus-specific IgG and IgM antibodies by the indirect immunofluorescence test and ELISA, respectively. Late-convalescent-phase serum was also collected from 18 of these patients 3 to 24 months postinfection and assayed. The IgM ELISA values were strongly positive in sera collected during the first 2 months; at 3 to 9 months, they were negative or in the lower range of significance, and at 24 months all sera were negative. Paired sera from NE patients often fail to show seroconversion or a significant titer rise when tested by indirect immunofluorescence. Since all acute- and early-convalescent-phase sera were positive by IgM ELISA, this test could become an important tool for early diagnosis of acute human NE infections.     

The humoral response to Puumala virus infection (nephropathia epidemica) investigated by viral protein specific immunoassays

Summary Enzyme-linked immunosorbent assays for determination of antibodies directed to the nucleocapsid protein (N) or to either of the two envelope glycoproteins (G1 and G2) of Puumala virus were designed and evaluated. The assays were proven to be entirely restricted for each viral structural protein by biotin-labelled monoclonal antibodies. Sera from sequentially bled nephropathia epidemica patients (acute, convalescent, and 2-year sera) and sera from 10–20 year convalescents were examined for antibody specificity. All but one (n=19) acute phase sera were shown to contain IgM antibodies directed to all three viral proteins. In the convalescent specimens the proportions of IgM to the different viral components were similar, but lower, when compared to the acute samples. Low levels of IgM against N and G2 were found in two out of ten 2-year sera. No virus-specific IgM were detected in sera drawn 10–20 years after infection. IgG antibodies to all three viral proteins were detected in all except one acute phase serum. The IgG response initially increased more rapidly to N, as compared to the anti-glycoprotein responses. The levels of glycoprotein-specific IgG were considerably increased 2 years after the disease, when compared to the levels detected in the convalescent specimens. The levels and specificities of IgG in very late convalescent sera (drawn 10–20 years after disease) resembled those detected 2 years after infection.     

Electron microscopy of nephropathia epidemica cell nuclei in kidney biopsies.

Ultrastructural changes in cell nuclei were studied in kidney biopsies from 18 patients suffering from Nephropathia epidemica. Three patients showed small nuclear particles in a large aggregate in a few cells of the distal tubule. The particles had a diameter of about 30 nm and their occurrence was not associated with intravenous glucose infusions. Large light nuclear bodies were numerous in the nuclei of both interstitial and tubular cells. Many showed strands of darker material about 35 nm in diameter at their center. Nuclear vesicles with varying amounts of membrane debris were seen in both tubular and interstitial cells. Occasional interstitial lymphocytes showed abnormal margination of chromatin. Of the changes observed the small nuclear particles are not found in kidney biopsies in other conditions and it is possible that they are aggregates of viral protein.     

急性冠脉综合征患者pentraxin-3与纤维蛋白原的变化

目的： 了解急性冠脉综合征患者炎性指标pentraxin-3与血栓指标纤维蛋白原（FIB）的变化。方法: 回顾性研究35例急性心肌梗死患者、27例不稳定心绞痛患者及15例健康体检者，所有研究对象清晨空腹抽血，检测其血浆pentraxin-3、FIB水平，并进行比较。结果: 急性冠脉综合征患者血pentraxin-3、FIB水平明显高于健康体检者，差异显著(P<0.01)；急性心肌梗死组高于不稳定性心绞痛组，差异显著(P<0.05)。Pentraxin-3浓度与FIB浓度之间存在正相关关系(P<0.01)。结论: 作为炎性指标pentraxin-3与血栓指标纤维蛋白与冠心病发生急性冠脉综合征相关，且两者相辅相成，可能共同促进急性冠脉综合征的发生。     

Circulation and diagnostics of Puumala virus in Norway: nephropatia epidemica incidence and rodent population dynamics

Hantaviruses pose a public health concern worldwide causing haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). Puumala virus (PUUV) is the most prevalent hantavirus in Central and Northern Europe, and causes a mild form of HFRS, also known as nephropathia epidemica (NE). In nature, the main host of PUUV is the bank vole (Myodes glareolus), and transmission to humans occurs through inhalation of aerosols from rodent excreta. Nephropathia epidemica is particularly prevalent in Nordic countries, however, few studies of PUUV have been performed in Norway. The aim of this study was to analyse the dynamics of PUUV in Norway and compare with bank vole population dynamics, and also to complement the current diagnostic methodology of NE in Norway. Our results showed a significant seasonal and geographical variation of NE, and a general parallel peak trend between bank vole population densities and human NE incidence. A real‐time and a nested PCR were successfully established as an invaluable diagnostic tool, with detection and sequencing of PUUV in a human serum sample for the first time in Norway. Phylogenetic analysis showed clustering of the obtained human sample with previous Norwegian bank vole isolates.     

血浆TPO水平变化与血小板减少疾病的关系

目的:探讨血浆血小板生成素(Thrombopoietin,TPO)水平变化与血小板减少疾病的关系。方法:采用多抗夹心酶联免疫吸附法对68例各种不同原因致血小板减少患者通过应用白介素-11(rhIL-11)来动态检测TPO水平,rhIL-11剂量为25μg/(kg.d),皮下注射,连用10天。结果:(1)急性白血病(Acute leukemia,AL)化疗后血小板减少患者TPO水平低于正常对照组;再生障碍性贫血(Aplastic anemia,AA)及骨髓增生异常综合征(Myelodysplastic syndrome,MDS)患者TPO水平高于正常对照组;原发性血小板减少性紫癜(Idiopathic thrombocytopenic purpura,ITP)及肝硬化(Liver cirrhosis)患者TPO水平与正常对照组无明显差异。而其中的白血病化疗后血小板减少患者和AA患者的骨髓巨核细胞数较TPO正常组显著降低。(2)上述疾病患者用rhIL-11有效者TPO水平趋于正常,无效或疗效欠佳者,则TPO无变化。有效者TPO水平与血小板计数呈负相关。结论:血浆TPO检测,有助于临床鉴别各种血小板减少疾病的病因,对血小板减少患者合理应用rhIL-11提供理论的依据。     

BDNF plasma levels in acute stroke

The transport of brain derived neurotrophic factor (BDNF) across the blood-brain barrier (BBB) is negligible in normal conditions. However, BDNF might pass through the BBB when BBB is disrupted by a pathological condition such as stroke. This migration of BDNF through the BBB might be important during post-ischemic phase since BDNF can exert a protective action in the site of lesion. This study aimed to investigate plasma levels of BDNF in the acute phase of stroke in humans. Serial venous blood samples were taken in ten patients with acute stroke at the admission to the Stroke Unit and on the following 4 days. In the same samples we also evaluated the plasma levels of S100beta protein, a marker of BBB disruption. There was no significant change in BDNF plasma levels in our patients, even in the presence of a pronounced BBB dysfunction, as demonstrated by a significant increase of S100beta protein concentrations at days 2 and 3 after stroke. Our data, though indirectly, suggest that there is no significant increase in endogenous extracellular BDNF after a stroke in humans.     

The effect of valsartan and nebivolol treatment on ADMA and pentraxin-3 levels in hypertensive patients

Long pentraxin 3 (PTX3) is a recently discovered multimeric inflammatory mediator that is structurally linked to short pentraxins, such as C-reactive protein (CRP) and serum amyloid P component. PTX3 is produced by a variety of tissues and cells, including vascular endothelial cells and macrophages. Because of its extrahepatic synthesis (in contrast to CRP), the PTX3 level is believed to be a true independent indicator of disease activity because PTX3 is produced at sites of inflammation and is intimately linked to endothelial dysfunction. PTX3 also has key functions in innate immunity and has been identified in atherosclerotic lesions. Previously, PTX3 was associated with myocyte damage in myocardial infarction (MI), mortality after MI, and unstable angina. Because PTX3 release is likely a specific response to vascular damage, PTX3 levels may provide more explicit information on development and progression of atherosclerosis than nonspecific markers like CRP and interleukin-6. Asymmetric dimethylarginine (ADMA) is a naturally occurring component of human blood plasma. More than one decade ago ADMA was first reported to exert biological effects by inhibiting nitric oxide synthesis. Many researchers today agree that ADMA may play a prominent role in the pathogenesis and in the progression of cardiovascular diseases. In this study PTX3 and ADMA levels investigated of valsartan and nebivolol's effect on newly diagnosed hypertensive patients.     

Detection of specific serum immunoglobulin M in nephropathia epidemica (Scandinavian epidemic nephropathy) by a biotin-avidin-amplified immunofluorescence method.

A biotin-avidin-amplified indirect immunofluorescence method was used to demonstrate specific serum immunoglobulin M (IgM) antibodies in nephropathia epidemica, the Scandinavian type of hemorrhagic fever with renal syndrome. The antigen in the test was the cross-reacting agent of Korean hemorrhagic fever, Hantaan virus. Sixty-two serum samples from 15 patients with clinically typical nephropathia epidemica were analyzed. Eleven patients had specific IgM in one or more serum samples. The IgM could be demonstrated from day 2 up to day 37, and all patients had detectable specific IgM within 15 days after the onset of disease. In 49 control serum samples, no specific IgM could be detected, indicating a high specificity for the method. The findings demonstrate that the biotin-avidin-amplified immunofluorescence IgM assay is a useful tool in the diagnosis of early nephropathia epidemica disease.     

Decreased IL-35 levels in patients with immune thrombocytopenia

IL-35 is a novel heterodimeric anti-inflammatory cytokine consisting of Epstein–Barr virus-induced gene 3 (EBI3) and the p35 subunit of IL-12. IL-35 has been shown to possess the potency of inhibiting the CD4+ effector T cells and alleviating autoimmune diseases. In the study we investigated the levels of IL-35 as well as its prospective role in immune thrombocytopenia (ITP).ELISA was adopted to measure plasma IL-35, TGF-β and IL-10 levels. The mRNA expression levels of P35 and EBI3 in peripheral blood mononuclear cells (PBMCs) were studied based on real-time quantitative PCR. The correlation between plasma cytokine levels and clinical parameters was analyzed. Significantly lower plasma IL-35 levels were found in active ITP patients compared with those in remission (p = 0.017) and the healthy controls (p < 0.001). In active ITP patients, the plasma IL-35 levels displayed a significantly positive correlation with platelet counts (r = 0.5335, p < 0.0008). Further, P35 mRNA expression levels were lower in patients with active ITP than patients in remission (p = 0.033) and normal controls (p = 0.016).Thus, for the first time, this research reported a dramatically decreased IL-35 levels in ITP patients, suggesting that IL-35 may be involved in the pathogenesis of ITP.