Seroepidemiology of enterovirus D68 in a healthy population in Beijing, China, between 2012 and 2017: A retrospective study

To investigate the seroepidemiological features of enterovirus D68 (EV-D68) in the healthy population from 2012 to 2017 in Beijing, China. A retrospective cross-sectional investigation was conducted using serum specimens collected from healthy individuals in Beijing from 2012 to 2017. These samples were tested for neutralization antibodies (NtAbs) against EV-D68. The sera from six EV-D68 infected patients in the acute or convalescent phase were used to determine the protection level of NtAbs against EV-D68. The geometric means of the titers (GMT) of EV-D68 NtAbs in 2012 and 2017 were 92.82 and 242.91, respectively; the seroprevalences of EV-D68 were 89.43% and 98.43%, respectively. The GMT reached its peak in the 11 to 15 age group in 2012, while in 16 to 20 age group in 2017. We also observed that EV-D68 NtAbs titers of six sera from the acute phase were all less than equal to  1:64 and that of three sera from the convalescent phase were all more than 1:64. Anti-EV-D68 NtAbs in the population remained low from 2012 to 2016 but increased significantly in 2017. Although most of the EV-D68 infections remain undetected in Beijing, the risk of a large outbreak of EV-D68 exists and should be taken seriously.

A spatial study on serum selenoprotein P and Keshan disease in Heilongjiang Province, China

BACKGROUND

Few spatial studies on serum selenoprotein P (SELENOP) and Keshan disease (KD) have been reported at the county-level in Heilongjiang province, China. This study aimed to provide visualized spatial epidemiological evidence of selenium molecular marker in residents living in endemic areas for the precise assessment of prevention, control, and elimination of KD.

METHODS

Using a spatial ecological study design, 587 subjects living in cities, townships, and rural areas of 50 KD endemic counties and 37 non-endemic counties in Heilongjiang province were investigated. The serum SELENOP levels of the participants were measured by enzyme-linked immunosorbent assay. Thematic maps were created, and spatial regression analysis was conducted using ordinary least squares.

RESULTS

The mean serum SELENOP level of the 587 subjects was 7.4 ± 3.0 μg/mL. The mean levels of serum SELENOP were higher in cities (7.4 ± 2.9 μg/mL) and townships (7.9 ± 3.2 μg/mL) than in rural areas (6.0 ± 3.0 μg/mL). The mean levels of serum SELENOP were trending towards high levels in non-endemic areas (7.4 ± 3.0 μg/mL) than in KD endemic areas (6.3 ± 3.3 μg/mL). Spatial regression analysis showed that the serum SELENOP level was positively correlated with the per capita gross domestic product.

CONCLUSION

Selenium deficiency may still exist in some KD endemic counties in Heilongjiang province, including Lingdong, Nenjiang, and Baiquan; these counties should be considered as key areas for precision prevention, control, and elimination of KD. Inclusion of selenium in the national surveillance of KD will provide more evidence for the assessment of KD elimination from a selenium nutrition perspective.

Antibodies to Enteroviruses in Cerebrospinal Fluid of Patients with Acute Flaccid Myelitis

Acute flaccid myelitis (AFM) has caused motor paralysis in >560 children in the United States since 2014. The temporal association of enterovirus (EV) outbreaks with increases in AFM cases and reports of fever, respiratory, or gastrointestinal illness prior to AFM in >90% of cases suggest a role for infectious agents. Cerebrospinal fluid (CSF) from 14 AFM and 5 non-AFM patients with central nervous system (CNS) diseases in 2018 were investigated by viral-capture high-throughput sequencing (VirCapSeq-VERT system). These CSF and serum samples, as well as multiple controls, were tested for antibodies to human EVs using peptide microarrays. EV RNA was confirmed in CSF from only 1 adult AFM case and 1 non-AFM case. In contrast, antibodies to EV peptides were present in CSF of 11 of 14 AFM patients (79%), significantly higher than controls, including non-AFM patients (1/5 [20%]), children with Kawasaki disease (0/10), and adults with non-AFM CNS diseases (2/11 [18%]) (P = 0.023, 0.0001, and 0.0028, respectively). Six of 14 CSF samples (43%) and 8 of 11 sera (73%) from AFM patients were immunoreactive to an EV-D68-specific peptide, whereas the three control groups were not immunoreactive in either CSF (0/5, 0/10, and 0/11; P = 0.008, 0.0003, and 0.035, respectively) or sera (0/2, 0/8, and 0/5; P = 0.139, 0.002, and 0.009, respectively).IMPORTANCE The presence in cerebrospinal fluid of antibodies to EV peptides at higher levels than non-AFM controls supports the plausibility of a link between EV infection and AFM that warrants further investigation and has the potential to lead to strategies for diagnosis and prevention of disease.

A spatial ecological study of selenoprotein P and Keshan disease

Few spatial ecological studies on selenoprotein P (SePP) and Keshan disease (KD) have been reported. The main objective of this study is to investigate the relationships of SePP with KD, economic indicators and soil selenium and to visualize the evidence for KD precise prevention and control. An ecological study design was employed. The serum SePP of 2351 subjects living in rural areas, general cities and developed cities in 15 KD endemic provinces and 13 KD non-endemic provinces in China were measured. Spatial description and spatial analysis of SePP were conducted. The subjects were adults aged. The mean serum SePP level of KD endemic area residents was 14.20 mg/L, significantly lower than that in non-endemic areas, 15.30 mg/L (t = - 3.19, P = 0.0010). Serum SePP levels were low among the people in the KD endemic provinces of Shandong, Inner Mongolia, Heilongjiang, etc. The mean serum SePP level of the 2351 people was 15.04 (95% CI: 14.76 and 15.31) mg/L. The mean serum SePP levels of residents in developed cities, general cities and rural areas were 16.54 mg/L, 14.98 mg/L and 14.44 mg/L, respectively, and were significantly different (F = 17.00, P < 0.0010). Spatial regression analysis showed that the spatial distribution of SePP was positively correlated with per capita consumption expenditure and soil selenium. Selenium deficiency may still exist among residents living in the KD endemic provinces. Shandong, Inner Mongolia, and Heilongjiang should be the target provinces, visualized by spatial analysis, for KD precise prevention and control.

Severity of enterovirus A71 infection in a human SCARB2 knock-in mouse model is dependent on infectious strain and route

Enterovirus A71 (EV-A71) is a major etiological agent of human hand, foot and mouth disease, and it can cause severe neurological complications. Although several genotypes of EV-A71 strains are prevalent in different regions of the world, the genotype C4 has circulated in mainland China for more than 20 years. The pathogenicity of different EV-A71 clinical isolates varies and needs to be explored. In this study, hSCARB2 knock-in mice (N = 181) with a wide range of ages were tested for their susceptibility to two EV-A71 strains with the subgenotypes C4 and C2, and two infection routes (intracranial and venous) were compared. The clinical manifestations and pathology and their relationship to the measured viral loads in different tissues were monitored. We observed that 3 weeks is a crucial age, as mice younger than 3-week-old that were infected became extremely ill. However, mice older than 3 weeks displayed diverse clinical symptoms. Significant differences were observed in the pathogenicity of the two strains with respect to clinical signs, disease incidence, survival rate, and body weight change. We concluded that hSCARB2 knock-in mice are a sensitive model for investigating the clinical outcomes resulting from infection by different EV-A71 strains. The intracranial infection model appears to be suitable for evaluating EV-A71 neurovirulence, whereas the venous infection model is appropriate for studying the pathogenicity of EV-A71.

Understanding physician antibiotic prescribing behavior for children with enterovirus infection

Background

Our previous study demonstrated that pediatricians prescribe antibiotics without proper clinical justification to patients with enterovirus infection, although antibiotics are not effective in treating the infections caused by these viruses. To improve the quality of healthcare, we aim to evaluate the association of clinical and demographic characteristics of patients and further to identify the determining factors for prescribing antibiotics to children experiencing enterovirus infection.

Methods

We retrospectively reviewed the medical records of children who were hospitalized between January 2008 and December 2016 with a diagnosis of herpangina or hand-foot-mouth disease (HFMD). We identified those children who were prescribed antibiotics for at least 24 hours during admission. We conducted a retrospective descriptive study to analyze data in order to determine the factors associated with pediatrician antibiotics prescribing for enterovirus infection.

Results

In the nine years of study period, the rate of antibiotics use was about 13% in these patients. A total of 3659 patients were enrolled during 2008~2012 and analyzed in detail. Elevated levels of C-reactive protein (CRP) and presence of leukocytosis in blood (WBC) were both significantly associated with pediatrician antibiotic prescribing for enterovirus infection (p<0.001). Between different specialistic devisions, there was significantly different proportion of antibiotics utilization for patients. In further analysis of antibiotics prescribing by Receiver operating characteristic (ROC) curve method, the level of CRP significantly had more the area under curve (0.708) compared with the count of WBC (p<0.05).

Conclusions

The present study indicates that higher serum level of CRP is strongly associated with pediatricians prescribing antibiotics for children experiencing herpangina or HFMD. Antibiotic prescribing is a complex process. Pediatricians should be more judicious in decision-making time by their specialistics. Our findings would shed new light on process and allay the concern about inappropriate antibiotics.

A cross-sectional seroepidemiology study of EV-D68 in China

Enterovirus 68 (EV-D68) is associated with respiratory diseases, such as acute upper respiratory tract infections (URTIs), lower respiratory tract infections (LRTIs), pneumonia, neurological diseases, and acute flaccid myelitis (AFM). In recent years, there have been global outbreaks of EV-D68 epidemics. However, there is no effective vaccine against EV-D68, and the understanding of the seroprevalence characteristics of EV-D68 is limited. To evaluate the epidemiological features of this emerging infection in mainland China, serum samples from 20 pairs of pregnant women and their neonates, 405 infants and children (ages 1 month-15 years), and 50 adults were collected to measure EV-D68 neutralizing antibodies (NtAbs). The results showed that the geometric mean titers (GMTs) of pregnant women and their neonates were 168 (95%CI: 93.6-301.7) and 162.3 (95%CI: 89.9-293.1), respectively. The seroprevalence rate of EV-D68 antibodies was negatively correlated with age in 1-month-old to 12-month-old infants (84% for 1-month-old infants vs 10% for 1-year-old infants), whereas it was positively correlated with age for 1-year-old to 15-year-old children (10% for 1-year-old children vs 92% for 15-year-old children). This study evaluated maternal antibodies against EV-D68 in neonates. Our results showed that if mothers had high levels of anti-EV-D68 NtAbs, the NtAbs titers in their neonates were also high. The GMTs and seroprevalence rates of each age group indicated that EV-D68 infection was very common in China. Periodical EV-D68 seroprevalence surveys and vaccination campaigns should be the top priority for preventing EV-D68 infection.

Network Analysis of Se-and Zn-related Proteins in the Serum Proteomics Expression Profile of the Endemic Dilated Cardiomyopathy Keshan Disease

Keshan disease (KD) is an endemic cardiomyopathy with high mortality. Selenium (Se) and zinc (Zn) deficiencies are closely related to KD. The molecular mechanism of KD pathogenesis is still unclear. There are only few studies on the interaction of trace elements and proteins associated with the pathogenesis of KD. In this study, isobaric tags for relative and absolute quantitation (iTRAQ)-coupled two-dimensional liquid chromatography tandem mass spectrometry (2DLC-MS/MS) technique analysis was used to analyze the differential expression of proteins from serum samples. Comparative Toxicogenomics Database (CTD) was used to screen Se- and Zn-associated proteins. Then, pathway and network analyses of Se- and Zn-associated proteins were constituted by Cytoscape ClueGO and GeneMANIA plugins. One hundred and five differentially expressed proteins were obtained by 2DLC-MS/MS, among them 19 Se- and 3 Zn-associated proteins. Fifty-two pathways were identified from ClueGO and 1 network from GeneMANIA analyses. The results showed that Se-associated proteins STAT3 and MAPK1 and Zn-associated proteins HIF1A and PARP1, the proteins involved in HIF-1 signaling pathway and apoptosis pathway, may play significant roles in the pathogenesis of KD. The approach of this study would be also beneficial for further dissecting molecular mechanism of other trace element-associated disease.

Association between Antioxidant Enzyme Activities and Enterovirus-Infected Type 1 Diabetic Children

OBJECTIVE

To examine the effect of infection with Enterovirus (EV) in children with type 1 diabetes (T1D) on the activities of serum antioxidant enzymes in diabetic and nondiabetic controls.

SUBJECTS AND METHODS

Three hundred and eighty-two diabetic and 100 nondiabetic children were tested for EV RNA using reverse transcriptase (RT)-PCR. The activities of serum superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were also estimated in diabetic patients infected with EV (T1D-EV+), those not infected with EV (T1D-EV-), and in nondiabetic controls.

RESULTS

The frequency of EV was higher in diabetic children (100/382; 26.2%) than in healthy controls (0/100). Levels of fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c) and C-reactive protein (CRP) were significantly higher but C-peptide was significantly lower in diabetic children than in controls. CRP levels were higher in the T1D-EV+ group than in the T1D-EV- group, and higher in all diabetic children than in nondiabetic controls. The activities of the antioxidant enzymes GPx, SOD, and CAT decreased significantly in diabetic children compared to in controls. Moreover, the activities of the enzymes tested were significantly reduced in the T1D-EV+ group compared to in the T1D-EV- group.

CONCLUSION

Our data indicate that EV infection correlated with a decrease in the activity of antioxidant enzymes in the T1D-EV+ group compared to in the T1D-EV- group; this may contribute to β cell damage and increased inflammation.

The Coincidence of Newly Diagnosed Type 1 Diabetes Mellitus with IgM Antibody Positivity to Enteroviruses and Respiratory Tract Viruses

OBJECTIVE

Viruses trigger and promote islet cell destruction and cause type 1 diabetes mellitus (T1DM). However, the existence of a cause-and-effect relationship is under debate. The aim of this study is to investigate the sero-epidemiological and molecular evidence on enteroviruses and respiratory viruses in patients with newly diagnosed T1DM during the cold season.

DESIGN

Forty children newly diagnosed with T1DM and 30 healthy children who presented to the clinic over the course of a year were included in the study. The IgM antibodies against enteroviruses and respiratory viruses were studied using the indirect immunofluorescence assay (IFA) test, and no CBV4-specific RNA was detected in the children. The onset times of T1DM were classified into fall-winter and spring-summer seasons and separated into cold, moderate, or warm months in terms of temperature.

RESULTS

The percentages of viral IgM antibodies against most common viruses were detected in the patients as follows: influenza B (IVB) (70%), echovirus 7 (ECHO7) (45%), parainfluenza virus 4 (PIV4) (40%), coxsackievirus A7 (CAV7) (27.5%), and H3N2 (22.5%). Compared with the control group, the above viruses had a significant association with T1DM (p ≤ 0.001, p ≤ 0.001, p = 0.035, p = 0.003, and p = 0.023, resp.). CBV4-specific RNA was not detected in any serum. A total of 75% and 95% patients were diagnosed with T1DM in the fall-winter seasons and cold-moderate months, respectively.

CONCLUSION

Our study demonstrates the significant association between T1DM and the presence of IgM antibodies against IVB, ECHO7, PIV4, CAV7, and H3N2, and the majority of newly diagnosed T1DM appeared in the fall-winter season. It suggests that enteroviruses and respiratory viruses, in addition to seasonal variation, could play a role in the etiopathogenesis and clinical onset of T1DM.

Serum quantitative proteomic analysis of patients with keshan disease based on iTRAQ labeling technique: A first term study

Keshan disease (KD), an endemic myocardiopathy, with unknown etiology, is still threatening human health. Proteomics studies of Keshan disease is rarely known. In the current study, isobaric tags for relative and absolute quantitation (iTRAQ) labeling coupled with two-dimensional liquid chromatography-tandem mass spectrometry (2D-LC-MS/MS) was firstly used to screen for the differentially expressed proteins (DEPs) in serum between Keshan disease and healthy residents in endemic area. 27 differentially expressed proteins were quantified, 9 of which were significantly altered (fold change > 1.2 or < 0.8) between the two groups. Bioinformatic analysis revealed that a wide variety of biology process played roles in KD pathophysiology. These differentially expressed proteins were mainly involved in complement coagulation pathways. A significant high serum level of LGALS3BP were observed. Our first term study in KD proteomics provided new view into the molecular mechanisms of KD disease.

Enteroviruses in blood of patients with type 1 diabetes detected by integrated cell culture and reverse transcription quantitative real-time PCR

AIMS

Enteroviruses (EV) have been associated with type 1 diabetes (T1D), but EV RNA detection has been reported in only a small proportion of T1D patients. We studied whether integrated cell culture and reverse transcription real-time PCR could improve EV detection in blood samples from patients with T1D.

METHODS

Blood was collected from 13 patients with T1D. The presence of EV RNA in blood was investigated by using real-time RT-PCR. In addition, plasma and white blood cells (WBC) were inoculated to BGM and Vero cell line cultures. Culture supernatants and cells collected on day 7 and day 14 were tested for EV RNA by real-time RT-PCR. Enterovirus identification was performed through sequencing of the VP4/VP2 region.

RESULTS

Enterovirus RNA was detected in blood by using real-time RT-PCR in only one out of 13 patients. The detection of EV RNA in cultures inoculated with clinical samples (plasma and/or WBC) gave positive results in five other patients. The viral loads were low, ranging from 45 to 4420 copies/ng of total RNA. One isolate was successfully identified as coxsackievirus B1.

CONCLUSIONS

Integrated cell culture and reverse transcription real-time PCR can improve the detection rate of EV in blood samples of patients with T1D and can be useful to investigate further the relationship between EV and the disease.

The role of the persistent enterovirus infection in development of acute stroke

INTRODUCTION

The role of enteroviruses in development of dilated cardiomyopathy, myocardial infarction, myocarditis, pericarditis is known.

THE AIM

To examine the role of chronic enterovirus infections in development of acute stroke.

MATERIAL AND METHODS

Blood samples from 72 patients with acute stroke (study group) and 35 patients without vascular disease (control group) were investigated by reverse transcription polymerase chain reaction for the presence of enterovirus RNA, by using virological method to detect enteroviruses, by ELISA for the levels of IgM and IgG antibodies to enteroviruses.

RESULTS

The enteroviruses genomes were detected significantly often in the serum of patients with stroke (23,6 ± 5,9%) than in control group (2,9 ± 2,8%). The viruses were isolated and were identified as Coxsackie B (serotypes 2, 3, 4) and ECHO (serotypes 6, 9, 27 (two strains), 29), three strains have not been identified in study group. IgM to enteroviruses were not found in the sera of both groups of patients. IgG to enteroviruses were detected in 17 patients in study group (23,6 ± 5,9%) and 2 patients in control group (5,7 ± 3,9%). The presence of enteroviruses genomes and IgG in sera of patients in control group (11,1 ± 3,7%) indicate the persistence of enteroviruses. The proportion of patients with IgG to enteroviruses in sera is higher in study group (12,5 ± 3,9%) than in control group (5,7 ± 3,9%).

CONCLUSION

The enterovirus infections play trigger role in development of acute stroke.

A pediatric patient with interstitial pneumonia due to enterovirus D68

Enterovirus D68 (EV-D68) infection is associated with upper and lower respiratory tract symptoms such as fever, cough, and wheezing. Pediatric patients with EV-D68 infection easily develop more severe respiratory complications compared to patients infected with other species of enterovirus, and consequently, have a higher rate of hospitalization and admission to intensive care units. Therefore, the clinical picture of respiratory complications associated with EV-D68 infection needs to be elucidated. Here, we report a 4-year-old girl of EV-D68 infection that required artificial respiration management within 24 h from the onset of cold symptoms. The patient was diagnosed with interstitial pneumonia on the basis of chest imaging findings with patchy, funicular and frosted glassy shadows, increased blood markers of surfactant protein-A, surfactant protein-D and sialylated carbohydrate antigen KL-6, and increased neutrophils and lymphocytes in the bronchoalveolar lavage. Steroids showed a remarkable effect in her treatment. Further investigations are needed to confirm the efficacy of steroids for interstitial pneumonia due to EV-D68 infection. As rapid deterioration of respiratory status is observed in EV-D68 infection, the possibility of interstitial pneumonia may be considered.

Isolation and Characterization of Enteroviruses from Clinical Samples

Enterovirus infections are common in humans worldwide. Enteroviruses are excreted in feces during infection and can be detected from stool specimens by isolation in continuous laboratory cell lines. Characterization of enteroviruses is based on their antigenic and/or genetic properties.

[Analysis of seroepidemiology of enterovirus 71 diseases in children in Jiangsu province]

OBJECTIVE

To analyze the dynamic pattern and the distributive characteristics of neutralizing antibody against enterovirus 71 (EV-A71 ) in children aged 6-35 months in Jiangsu province from 2012 to 2014.

METHODS

From March, 2012 to March, 2014, a total of 1 276 children aged between 6 and 35 months were regularly followed up on day 0, year 1 and year 2 for EV-A71 neutralizing antibody test based on the enterovirus surveillance system, with the method of reporting by their guardian or being visited in Ganyu Sheyang Taixing Donghai Pizhou and Baoying in Jiangsu province. At the same time, samples were taken from the suspected persons infected by enterovirus. The χ(2) test or variance analysis was used to compare the difference of the positive rates and the geometric mean titer(GMT) of EV-A71 neutralizing antibody in different subjects.

RESULTS

In 2 years follow-up, the positive rates of EV-A71 antibody increased as the growth of the age,and the positive rates on day 0, year 1 and year 2 were 22.57% (288/1 276), 37.72%(444/1 177) and 42.84%(422/985), respectively (χ(2) values were 39.33, 56.41, 32.25; P< 0.001).The GMTs were 9.95, 15.37 and 24.05, respectively (F values were 22.90,46.36,41.58;P<0.001). In 2 years, the annually new infection rates were 13.47%(158/1 173) and 20.73%(192/926),respectively, and the annually decay rates of EV-A71 antibody were 2.81%(33/1 173) and 8.10%(75/926).

CONCLUSIONS

In 2012 to 2014, the positive rates and the GMTs of EV-A71 antibody of children increased as the growth of the age in Jiangsu. The higher annually new infection rate was in children aged 3 to 4 years. The EV-A71 neutralizing antibody level could maintain at least two years after natural infection.

Enterovirus 71 virion-associated galectin-1 facilitates viral replication and stability

Enterovirus 71 (EV71) infection causes a myriad of diseases from mild hand-foot-and-mouth disease or herpangina to fatal brain stem encephalitis complicated with pulmonary edema. Several severe EV71 endemics have occurred in Asia-Pacific region, including Taiwan, and have become a serious threat to children’s health. EV71 infection is initiated by the attachment of the virion to the target cell surface. Although this process relies primarily upon interaction between viruses and cell surface receptors, soluble factors may also influence the binding of EV71 to host cells.Galectin-1 has been reported to participate in several virus infections, but is not addressed in EV71. In this study, we found that the serum levels of galectin-1 in EV71-infected children were higher than those in non-infected people. In EV71 infected cells, galectin-1 was found to be associated with the EV71 VP1 and VP3 via carbohydrate residues and subsequently released and bound to another cell surface along with the virus. EV71 propagated from galectin-1 knockdown SK-N-SH cells exhibited lower infectivity in cultured cells and less pathogenicity in mice than the virus propagated from parental cells. In addition, this galectin-1-free EV71 virus was sensitive to high temperature and lost its viability after long-term storage, which could be restored following supplement of recombinant galectin-1. Taken together, our findings uncover a new role of galectin-1 in facilitating EV71 virus infection.

[Seroprevalence of the newer enterovirus types A71, A90 and B87 in healthy individuals in Shandong Province, China]

This study aimed to investigate antibody levels of the newer human enteroviruses (EV) A71, A90, and B87 in the population of Shandong Province, and provide a scientific basis for the development of prevention and control measures. In this study, serum specimens were collected from 400 individuals living in Yantai city, Shandong Province in 2010. EV-A71, A90, and B87 antibodies were detected using neutralization tests, and the results were analyzed by statistical methods. It was found that the positive neutralizing antibody rates of EV-A71, A90 and B87 in the population were 46.0%, 8.8%, and 47.0%, respectively. Their geometric mean titers (GMT) were 1 : 5.20, 1 : 1.49, and 1 : 4.02, respectively. Positive antibody rates for EV-A71 and EV-B87 were lowest in the 1-yr and 7-mo age groups, respectively. Positive rates increased gradually with age, and become consistent in the population aged >5 years. Positive antibody rates of EV-A90 were consistent across all age groups. Maternal antibody levels of EV-A71 declined rapidly after birth, and the increase in seroprevalence among 3-7 years old children implied that most EV-A71 infections occurred in preschool and early elementary school children. High positive antibody rates of EV-B87 in healthy individuals, especially children, implied that there may be an immune barrier within the general population. The population monitoring of EV-A90 should be strengthened, as its positive antibody rate is low.

The clinical correlation of regulatory T cells and cyclic adenosine monophosphate in enterovirus 71 infection

Background

Brainstem encephalitis (BE) and pulmonary edema (PE) are notable complications of enterovirus 71 (EV71) infection.

Objective

This study investigated the immunoregulatory characterizations of EV71 neurological complications by disease severity and milrinone treatment.

Study Design

Patients <18 years with virologically confirmed EV71 infections were enrolled and divided into 2 groups: the hand, foot, and mouth disease (HFMD) or BE group, and the autonomic nervous system (ANS) dysregulation or PE group. Cytokine and cyclic adenosine monophosphate (cAMP) levels, and the regulatory T cell (Tregs) profiles of the patients were determined.

Results

Patients with ANS dysregulation or PE exhibited significantly low frequency of CD4⁺CD25⁺Foxp3⁺ and CD4⁺Foxp3⁺ T cells compared with patients with HFMD or BE. The expression frequency of CD4⁻CD8⁻ was also significantly decreased in patients with ANS dysregulation or PE. Among patients with ANS dysregulation or PE, the expression frequency of CD4⁺Foxp3⁺ increased markedly after milrinone treatment, and was associated with reduction of plasma levels IL-6, IL-8 and IL-10. Plasma concentrations of cAMP were significantly decreased in patients with ANS dysregulation or PE compared with patients with HFMD or BE; however, cAMP levels increased after milrinone treatment.

Conclusions

These findings suggested decreased different regulatory T populations and cAMP expression correlate with increased EV71 disease severity. Improved outcome after milrinone treatment may associate with increased regulatory T populations, cAMP expression and modulation of cytokines levels.

[The exploration of the role of angiopoietin-2 in pulmonary edema induced by EV71 infection]

OBJECTIVE

To observe the clinic character of pulmonary edema (PE) induced by enterovirus 71 (EV71) and the change in angiopoietin-2 (Ang-2), and to explore the correlation between Ang-2 and PE.

METHODS

Twenty consecutive infants with PE induced by EV71 admitted to intensive care unit (ICU) of Binzhou Medical College Affiliated Hospital from May 2011 to September 2013 were prospectively enrolled in PE group; 20 infants with similar age infected by EV71 without PE and hospitalized in ICU were enrolled as non-PR group; and 20 similar age infants suffering from selective inguinal hernia operation were served as control group. Data of infants with or without PE were collected including vital signs, complete blood count, blood biochemistry tests, chest X-ray and cerebrospinal fluid at ICU admission. Pulmonary edema liquid and serum were collected from infants suffered from severe PE by tracheal intubation. Total protein, albumin and Ang-2 [enzyme linked immunosorbent assay (ELISA)] were determined and those of pulmonary edema liquid/serum (P/S) ratio were calculated.

RESULTS

Nine infants with PE died, and all of infants without PE survived. Body temperature, heart rate, blood pressure, white blood cell count (WBC), blood sugar and MD isoenzyme of creatine kinase (CK-MD) in EV71 infection infants were higher than those in controls, and albumin and oxygenation index (PaO(2)/FiO(2)) were lowered. Heart rate, blood sugar and WBC of infants with PE were significantly higher than those of infants without PE [heart rate (bmp): 181 ± 31 vs. 146 ± 19, t=3.397, P=0.003; blood sugar (mmol/L: 14.9 ± 9.8 vs. 6.3 ± 1.5, t=2.793, P=0.012; WBC (x10(9)/L): 22.1 ± 9.8 vs. 10.2+3.6, t=3.579, P=0.002], and serum albumin and PaO(2)/FiO(2) of infants with PE were significantly lower [albumin (g/L): 33.6+5.9 vs. 42.7 ± 2.9, t=3.258, P=0.004; Pa(2)/FiO(2) (mmHg, 1mmHg=0.133 kPa): 142 ± 76 vs. 396 ± 39, t=3.927, P=0.000]. Cerebrospinal fluid pressure was significantly elevated in both non-PE and PE groups, the number of nucleated cells were normal or mildly to moderately elevated, most were mononuclear cells, and protein content were normal. Ang-2 levels of infants with PE [236.17 (167.63, 366.65) ng/L] was higher than that of control infants [19.67 (8.72, 33.68) ng/L] and infants without PE [23.46 (13.28, 46.77) ng/L, both T=210, both P=0.000]. Pulmonary edema liquid was collected from 8 infants with severe PE. Total protein, albumin, lactate dehydrogenase (LDH) and Ang-2 in severe PE infants were elevated. Total protein of P/S ratio was 0.67, 1.33, 1.12, 0.72, 0.84, 0.73, 1.09, 1.24, albumin of P/S ratio was 0.72, 1.64, 0.84, 0.87, 1.06, 0.92, 1.12, 1.48, LDH of P/S 0.92, 1.03, 1.17, respectively.

CONCLUSIONS

Pulmonary edema liquid of infants with PE induced by EV71 infection os rich of protein, and Ang-2 level rises in serum and pulmonary edema liquid. Ang-2 may involve in pulmonary vascular leak and developments of PE.

Plasma B-type natriuretic peptide study in children with severe enterovirus 71 infection: a pilot study

OBJECTIVES

Severe enterovirus 71 (EV71) infections in children can result in acute heart failure. B-type natriuretic peptide (BNP) is a good biomarker of myocardial stress. The purpose of this study was to use plasma BNP for the detection of EV71 infection with cardiac involvement.

METHODS

Patients with severe EV71 infections and healthy control subjects were studied: group 1 (n=30), normal controls; group 2 (n=20), EV71 infection with central nervous system involvement; and group 3 (n=3), EV71 infection with cardiopulmonary failure. The demographic and laboratory data including plasma BNP levels were analyzed statistically.

RESULTS

All group 2 patients recovered completely without neurological sequelae, and all group 3 patients survived without cardiac complications. Group 3 patients had higher troponin I, MB fraction of creatine kinase, and BNP levels than patients of the other groups. The median BNP values were <5 pg/ml in group 1, 9.5 pg/ml in group 2, and 238 pg/ml in group 3. Using a BNP cut-off value of 100 pg/ml to identify cases with severe EV71 infection and acute heart failure, the sensitivity and specificity were both 100%.

CONCLUSIONS

Children with severe EV71 infections have varying degrees of myocardial stress. Plasma BNP would be a sensitive and reliable biomarker for the detection of cardiac involvement in children with severe EV71 infections.

[Two-dimensional gel electrophoresis map of serum proteins in patients with chronic Keshan disease]

OBJECTIVE

To identify the different serum proteins expressed in patients with Keshan disease (KD).

METHODS

Two-dimensional gel electrophoresis (2-DE) was performed with serum samples from the patients with chronic KD and healthy controls to separate serum proteins. The gels were stained by sliver and scanned by Umax scanner. The data were analyzed by ImageMaster 2D software. KD related proteins were identified through searching the ExPASy SWISS-2DPAGE database.

RESULTS

Stable two-dimensional gel electrophoresis maps were established for serum samples of KD patients and healthy controls. A total of 808 and 814 protein spots were observed in KD patients and healthy controls, respectively. The two maps had 96.5475% identical protein spots and 44 differentially expressed protein spots. Eleven protein spots were expressed exclusively in KD patients and 12 protein spots only appeared in healthy controls. About 21 proteins were expressed in both groups but varied in quantities (14 proteins were over-expressed by more than 3 times and 7 proteins were under-expressed by more than 3 times in KD patients, P < 0.01). Among the 353 protein spots matched with the ExPASy-SWISS-2DPAGE databank, No. 1177 protein appeared in the KD patient was found to have the closest match with P02774 2-D0004T6 known as vitamin D binding protein (VDBP).

CONCLUSION

There is a significant difference in serum protein expression between KD patients and normal people. VDBP might play a role in cardiac muscle damage via inflammatory immune reactions.

[Monitoring of enterovirus circulation in Irkutsk region]

AIM

Monitoring of circulation of enteroviruses (EVI) in Irkutsk Region and study of regional specter of circulating enteroviruses.

MATERIALS AND METHODS

1419 samples from patients with suspected EVI, contact in foci ofenterovirus infection, acute intestine infections and 964 samples of sewage water were studied in total. In 2011 isolation of viral agents from 97 samples positive on enterovirus by RT-PCR from patients with preliminary EVI diagnosis and 5 samples of sewage water of Irkutsk city was carried out. Transplantable line of human rhabdomyosarcoma RD cell culture was used for isolation of enteroviruses. Infection of cells and 2 serial passages of the studied material were carried out. The isolates were typed in neutralization reaction (NR) with a set of 32 diagnostic type-specific immune sera against viral poliomyelitis I-III; Coxsackie B1-6; Coxsackie A2, A4, A7, A9, A10; ECHO 68 - 71; ECHO 2, 4, 7, 8, 9, 12, 16, 20, 25, 26, 27, 29, 31, 33.

RESULTS

In 2011 circulation of enterovirus serotypes that were previously absent on the territory of the region was established: ECHO 68, ECHO 70, ECHO 71. These strains were isolated from patients, circulation of ECHO 70 serotype was established also in samples of sewage water. The analysis of enterovirus landscape carried out showed the possibility of complication of epidemic situation on the territory of the region due to change of serovariants of causative agents of non-polioenterovirus infections and detection ofepidemically significant enteroviruses - ECHO 68, 70 and 71 serotypes.

CONCLUSION

Determination of specter ofenterovirus serotypes, detection of serotypes that had not previously circulated in Irkutsk Region allows to prognose epidemic situation on morbidity of enterovirus infections and timely develop and make decisions for ensuring epidemiologic welfare of the population.

[Screening of differentially expressed proteins in serum from subjects with Keshan disease by two-dimensional electrophoresis and mass and mass spectrometry]

OBJECTIVE

To screen differentially expressed proteins in serum in patients with Keshan disease (KD), peripheral blood protein expression spectrum between subjects with Keshan disease and health controls were compared.

METHODS

Differentially expressed protein spots were screened by two-dimensional gel electrophoresis (2-DE) between Keshan disease and health control subjects, and constitutive protein were identified by matrix assisted laser adsorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS).

RESULTS

9 differentially expressed protein spots were showed in 2-DE images and 8 differentially expressed proteins were identified by MALDI-TOF-MS. In them, 3 up-regulated proteins, mainly relatedd to lipid metabolism, apoptosis resistance, immunological regulation and 3 down-regulated proteins, involved to cellular iron ion homeostasis; 2 up-regulated proteins in serum in patients with KD versus controls from KD areas were detected, mainly associated with protease inhibition.

CONCLUSIONS

Haptoglobin, serum albumin, alpha-l-antitrypsin, transferring and alpha2-heremans schmid glycoprotein may be considered as candidate biological indicators used for diagnosis or prognosis of KD.

[Association of HLA-G 14bp gene polymorphisms and plasma sHLA-G level with susceptibility to EV71 infection in children]

OBJECTIVE

Explore the relationship between the HLA-G 14bp insertion/deletion polymorphism and the infection of Enterovirus 71 (EV71) for children.

METHODS

We genotyped HLA-G 14bp insertion/deletion polymorphism of 125 severe HFMD children infected with EV71 and 133 normal controls by PCR-PAGE;detected the plasma sHLA-G level of 66 heavy type and 15 critical type and 133 normal controls by ELISA.

RESULTS

Frequencies of the genotype 14 bp - / - ,14 bp + / - and 14 bp + / + were 49.6% , 42.4% and 8.0% for the severe HFMD children infected with EV71, and 34.6%, 48.9% and 16.5% for the normal controls, respectively. A significant difference was observed for the frequencies of the HLA-G 14bp genotype between the two groups(chi2 = 7.850, P = 0.020). And for the allele frequencies. The plasma sHLA-G levels in heavy type were dramatically higher than that in normal controls (Z = -9.692, P = 0.000). The plasma sHLA-G levels in children with critical HFMD were dramatically higher than that with heavy type (Z = -2.420, P = 0.016).

CONCLUSION

There was a relationship between the HLA-G 14 bp insertion/deletion polymorphism and the susceptibility to the severe HFMD children infected with EV71 and the plasma sHLA-G might be considered as a index for auxiliary diagnosis the severe HFMD infected with EV71.

Protection against enterovirus 71 with neutralizing epitope incorporation within adenovirus type 3 hexon

Enterovirus 71 (EV71) is responsible for hand, foot and mouth disease with high mortality among children. Various neutralizing B cell epitopes of EV71 have been identified as potential vaccine candidates. Capsid-incorporation of antigens into adenovirus (Ad) has been developed for a novel vaccine approach. We constructed Ad3-based EV71 vaccine vectors by incorporating a neutralizing epitope SP70 containing 15 amino acids derived from capsid protein VP1 of EV71 within the different surface-exposed domains of the capsid protein hexon of Ad3EGFP, a recombinant adenovirus type 3 (Ad3) expressing enhanced green fluorescence protein. Thermostability and growth kinetic assays suggested that the SP70 epitope incorporation into hypervariable region (HVR1, HVR2, or HVR7) of the hexon did not affect Ad fitness. The SP70 epitopes were thought to be exposed on all hexon-modified intact virion surfaces. Repeated administration of BALB/c mice with the modified Ads resulted in boosting of the anti-SP70 humoral immune response. Importantly, the modified Ads immunization of mother mice conferred protection in vivo to neonatal mice against the lethal EV71 challenge, and the modified Ads-immunized mice serum also conferred passive protection against the lethal challenge in newborn mice. Compared with the recombinant GST-fused SP70 protein immunization, immunization with the Ads containing SP70 in HVR1 or HVR2 elicited higher SP70-specific IgG titers, higher neutralization titers, and conferred more effective protection to neonatal mice. Thus, this study provides valuable information for hexon-modified Ad3 vector development as a promising EV71 vaccine candidate and as an epitope-delivering vehicle for other pathogens.

Children with islet autoimmunity and enterovirus infection demonstrate a distinct cytokine profile

Cytokines are upregulated in prediabetes, but their relationship with Enterovirus (EV) infection and development of islet autoimmunity is unknown. Cytokines (n = 65) were measured using Luminex xMAP technology in a nested case-control study of 67 children with a first-degree relative with type 1 diabetes: 27 with islet autoantibodies (Ab(+)) and 40 age-matched persistently autoantibody negative (Ab(-)) control subjects. Of 74 samples, 37 (50%) were EV-PCR(+) in plasma and/or stool (EV(+)) and the remainder were negative for EV and other viruses (EV(-)). Fifteen cytokines, chemokines, and growth factors were elevated (P ≤ 0.01) in Ab(+) versus Ab(-) children (interleukin [IL]-1β, IL-5, IL-7, IL-12(p70), IL-16, IL-17, IL-20, IL-21, IL-28A, tumor necrosis factor-α, chemokine C-C motif ligand [CCL]13, CCL26, chemokine C-X-C motif ligand 5, granulocyte-macrophage colony-stimulating factor, and thrombopoietin); most have proinflammatory effects. In EV(+) versus EV(-) children, IL-10 was higher (P = 0.005), while IL-21 was lower (P = 0.008). Cytokine levels did not differ between Ab(+)EV(+) and Ab(+)EV(-) children. Heat maps demonstrated clustering of some proinflammatory cytokines in Ab(+) children, suggesting they are coordinately regulated. In conclusion, children with islet autoimmunity demonstrate higher levels of multiple cytokines, consistent with an active inflammatory process in the prediabetic state, which is unrelated to coincident EV infection. Apart from differences in IL-10 and IL-21, EV infection was not associated with a specific cytokine profile.

The effect of DHEA treatment on the oxidative stress and myocardial fibrosis induced by Keshan disease pathogenic factors

Oxidative stress induced by the combined deficiencies of selenium (Se) and vitamin E (VE) is considered the basic factor of Keshan disease (KD). Dehydroepiandrosterone (DHEA) is a naturally occurring adrenal androgen that has antioxidant properties. We found that a Se- and VE-deficient diet induced KD lesions in rats, while 0.05, 0.125, and 0.25 g/kg DHEA caused a concentration-dependent inhibition in the development of oxidative stress and extracellular matrix (ECM) deposition in the left ventricles of the Se- and VE-deficient rats. In addition, DHEA counteracted activation of NFκB as well as the subsequent increase in TGFβ-1 and CTGF induced by the Se- and VE-deficient diet. These studies suggested that DHEA prevents oxidative stress and might be useful in treating Se and VE deficiency-related KD. These effects were based on its antioxidant effects and ECM deposition inhibition in left ventricles.

[Enterovirus infection as a risk factor of acute coronary syndrome and its complications]

Antigens of enteroviruses were detected quantitatively in the modified complement-binding reaction in blood samples from 102 of the 208 (49%) patients with ACS, in coronary artery tissues from 23 of 24 and heart from 51 of 94 (54.3%) patients with MI who died from cardiogenic shock and/or cardiac rupture. The relative level of enterovirus antigen (RLEVA) in the blood of patients with MI complicated and uncomplicated by cardiogenic shock and/or cardiac rupture was 0.42 +/- 0.04 and 0.29 +/- 0.02 arbitrary units respectively (p = 0.032) compared with 0.21 +/- 0.07 in patients with unstable angina (UA) (p = 0.0001). RLEVA in patients with UA was significantly lower than in those with uncomplicated MI (p < 0.011). RLEVA in necrotized myocardial areas after death from cardiogenic shock (0.54 +/- 0.18) and/or cardiac rupture (0.46 +/- 0.15) was higher than outside MI zones (0.30 +/- 0.14 and 0.26 +/- 0.10 respectively) (p < 0.01). RLEVA in coronary vessels feeding the necrotic zones of patients with MI complicated by cardiogenic shock (0.44 +/- 0.18) was higher (p = 0.03) than in the vessel feeding tissues outside the MI zone (0.29 +/- 0.19). It is concluded that enterovirus infection is a factor of ACS; it is directly involved in its pathogenesis and promotes the development of cardiogenic shock and/or cardiac rupture.

Environmental and genetic factors influence the relationship between circulating IL-10 and obesity phenotypes

Interleukin-10 (IL-10) is a centrally operating anti-inflammatory cytokine that plays a crucial role in the regulation of the innate immune system. It has strong inactivating properties on the inflammatory host response and has been related with viral persistence. We aimed to evaluate the association among circulating IL-10, obesity phenotypes, IL-10 and IL-10R1 gene polymorphisms, and the environmental exposure to viral infection. IL-10 -819C/T gene promoter and IL-10 receptor-1 -243A/G gene polymorphisms were studied in 760 subjects, whereas the former was also investigated in a replication study of 676 subjects. The association of circulating IL-10 levels (enzyme-linked immunosorbent assay) with the serum IgG against adenoviruses and enteroviruses was evaluated in a subset of 189 subjects. Circulating levels of IL-10 were increased in obese people and were positively associated with weight, BMI, waist, waist-to-hip ratio, fat mass, systolic pressure, and, interestingly, the titer of adenoviruses and enteroviruses. Obese subjects with adenovirus titer over the median had the highest circulating IL-10 concentration. Both obesity and adenovirus titer were independently associated with IL-10 variance. Nonmorbid obese T carriers for the -819CT IL-10 gene polymorphism had significantly higher BMI and waist circumference, and those with normal fasting glucose had increased fasting triglycerides. G carriers for the -536AG IL-10R1 gene polymorphism had higher systolic and diastolic pressures, and IL-10 levels; and obese G carriers had an increased waist-to-hip ratio. In summary, circulating IL-10 levels were associated not only with obesity status but also with genetic factors and with the exposure to environmental pathogens.

Enterovirus infection, CXC chemokine ligand 10 (CXCL10), and CXCR3 circuit: a mechanism of accelerated beta-cell failure in fulminant type 1 diabetes

OBJECTIVE

Fulminant type 1 diabetes is characterized by the rapid onset of severe hyperglycemia and ketoacidosis, with subsequent poor prognosis of diabetes complications. Causative mechanisms for accelerated beta-cell failure are unclear.

RESEARCH DESIGN AND METHODS

Subjects comprised three autopsied patients who died from diabetic ketoacidosis within 2-5 days after onset of fulminant type 1 diabetes. We examined islet cell status, including the presence of enterovirus and chemokine/cytokine/major histocompatibility complex (MHC) expressions in the pancreata using immunohistochemical analyses and RT-PCR.

RESULTS

Immunohistochemical analysis revealed the presence of enterovirus-capsid protein in all three affected pancreata. Extensive infiltration of CXCR3 receptor-bearing T-cells and macrophages into islets was observed. Dendritic cells were stained in and around the islets. Specifically, interferon-gamma and CXC chemokine ligand 10 (CXCL10) were strongly coexpressed in all subtypes of islet cells, including beta-cells and alpha-cells. No CXCL10 was expressed in exocrine pancreas. Serum levels of CXCL10 were increased. Expression of MHC class II and hyperexpression of MHC class I was observed in some islet cells.

CONCLUSIONS

These results strongly suggest the presence of a circuit for the destruction of beta-cells in fulminant type 1 diabetes. Enterovirus infection of the pancreas initiates coexpression of interferon-gamma and CXCL10 in beta-cells. CXCL10 secreted from beta-cells activates and attracts autoreactive T-cells and macrophages to the islets via CXCR3. These infiltrating autoreactive T-cells and macrophages release inflammatory cytokines including interferon-gamma in the islets, not only damaging beta-cells but also accelerating CXCL10 generation in residual beta-cells and thus further activating cell-mediated autoimmunity until all beta-cells have been destroyed.

[Study of the clinical and laboratory features of hand-foot-mouth disease]

OBJECTIVE

To study the clinical and laboratory features of the mild and severe hand-foot-mouth diseases (HFMD) in Shenzhen in 2008.

METHODS

145 cases were observed in East-Lake Hospital and Shenzhen Children's Hospital. Of the 145 cases, 124 mild cases and 21 severe cases were involved.All the clinical data and laboratory findings were collected and summarized. After collection of the acute and convalescent consecutive stools and peripheral bloods from the patients with HFMDI, EV71 genes were amplified from these samples by RT-PCR. Enterovirus 71 were cultured and isolated using Vero cell line and R&D cell line.

RESULTS

The WBC counts and blood glucose levels of the severe cases were significantly elevated, but the ages of the severe ones significantly decreased compared with those of the mild cases (P < 0.05). EV71 genes could be detected by RT-PCR with 35% positive rate in mild cases and 67% in severe cases. The EV71 gene detection rate of the severe cases was significantly increased in contrast to that of the mild ones. The EV71 were isolated and cultured from the stools of 9 patients, one specimens from the dead's stool. Two severe cases died of neurogenic pulmonary edema and brain-stem encephalitis.

CONCLUSIONS

EV71 mainly contributes to HFMD and is responsible for death of some severe cases. High fever, less rash, elevated white blood cell counts and blood glucose concentrations as well as age less than 4 years old should be used for prediction of severe cases.

[C3d enhances immune response to the secreted form of Coxsackie virus B3 VP1 DNA vaccine]

OBJECTIVE

To explore a strategy to enhance the specific immune response induced by secreted form of Coxsackie virus B3 (CVB3) capsid protein 1 (sVP1) gene vaccination against Coxsackie virus infection.

METHODS

Eukaryotic expression plasmid pcDNA3/sVP1-C3d3 was constructed by conjugating the 3 copies of C3d (C3d3) with the secreted form of sVP1 of CVB3. 42 BALB/c mice were randomly divided into 3 equal groups to be inoculated with pcDNA3/sVP1-C3d3, pcDNA3/sVP1 and pcDNA3 plasmids respectively once every 4 weeks for 3 times. 14 days after every inoculation venous blood was collected to measure the titer of neutralizing antibody. Three weeks after the last inoculation their spleens were taken out to detect the specific CTL cytotoxic activity. Three mice from each group underwent intraperitoneal injection of 3 LD(50) CVB3 and were killed 7 days later, and then the titer of blood viruses was measured. The remaining 8 mice underwent intraperitoneal injection of 5 LD(50) CVB3 and the survival status was observed for 21 days.

RESULTS

The titer of neutralizing antibody in the mouse blood increased along with the time after inoculation. The antibody titer and specific CTL cytotoxic activity 3 days after inoculation of the pcDNA3/sVP1-C3d3 group were 33.6 +/- 1.7 and 66.1% +/- 2.9% respectively, both significantly stronger than those of the pcDNA3/sVP1 group [(28.3 +/- 1.7) and (52.8% +/- 3.3%) respectively, both P < 0.05]. After lethal CVB3 challenge, the blood virus titer of the pcDNA3/sVP1-C3d3 group was significantly lower than that of the pcDNA3 group (P < 0.05), and the survival rate of pcDNA3/sVP1-C3d3 group was 50%, significantly higher than that of the pcDNA3 group (0, P < 0.05), however, not significantly different from that of the pcDNA3/sVP1 group (25%, P > 0.05).

CONCLUSION

C3d strongly enhances the specific immune response induced by SVP1 gene vaccination.

[Epidemiologic and etiologic characteristic of enterovirus infections in Khabarovsk region]

Results of epidemiologic, virologic, and serologic studies of enterovirus infections in Khabarovsk region from 1975 to 2006 were analyzed. Patterns of epidemic process of these infections were established: periodic change of dominating type of pathogen in the population; onset of the large epidemic peaks of incidence during emergence of circulation of new for the given area serotypes of enteroviruses; possibility of realization of several routes of virus transmission. Role of water factor in the progress of the epidemic process was revealed. Etiology of the large epidemic rise of aseptic meningitis incidence in Khabarovsk region in 2006 was established--the leading pathogens were ECHO viruses serotypes E6 and E30.

Comparison of total white blood cell count and serum C-reactive protein levels in confirmed bacterial and viral infections

We report the association of reaction in inflammatory markers with the microbiologic etiology of infection in children. Total white blood cell counts were increased in most pneumococcal and Escherichia coli infections, but in less than one-half of Staphylococcus aureus infections. Adenoviruses were the only viral agents that often increased total white blood cell counts or serum C-reactive protein levels.

Particle-induced myeloperoxidase release in serially diluted whole blood quantifies the number and the phagocytic activity of blood neutrophils and opsonization capacity of plasma

Luminol-amplified chemiluminescence (CL) from phagocytes has previously been shown to be almost completely dependent on the release of myeloperoxidase (MPO) from azurophilic granules. We measured the luminol-amplified chemiluminescence response (WBCL) by using serially diluted whole blood. In these experiments, non-opsonized and serum-opsonized zymosan (NWBCL and OWBCL, respectively) were used concurrently as phagocytosable particles. We found two whole-blood dilution ranges with clinical significance: first, <0.04% of whole blood in the reaction volume, where MPO released by the zymosan-activated leukocyte population came almost totally from neutrophils and the OWBCL response could be exploited as a measure of a neutrophil count in a given blood specimen, despite the pathophysiological state of the host. In contrast, the NWBCL response was two-fold in blood samples from bacterial infection patients compared to those of controls and patients with viral infection, suggesting the use of NWBCL for the differential diagnosis of bacterial infections from viral infections; second, 0.16-1.2% of whole blood in the reaction volume, where the opsonization capacity of plasma (OC(50)) can be determined. We also found that at whole blood content >0.04%, erythrocytes quickly start to absorb chemiluminescence light, and that at whole blood content >1.2%, plasma proteins, most probably albumin and fibrinogen, start to inhibit MPO release.

Enteroviruses and the risk of MS in the Finnish Twin Cohort

To investigate the possible association of enterovirus (EV) infection with the development of multiple sclerosis (MS). The role of various genetic and environmental factors has been intensively studied in the etiopathogenesis of MS but the cause of the disease has remained unknown. Enteroviruses are possible candidates because they are neurotropic and able to cause chronic infections. Serum and cerebrospinal fluid (CSF) were tested with reverse transcription-polymerase chain reaction specific for enteroviruses in 17 MS twin pairs. No enteroviral RNA was found in any serum (n = 34) or CSF (n = 12) sample. We found no evidence of enterovirus infection in twins with MS or their healthy siblings. To our knowledge this is a first study to assess the role of enterovirus infections in the risk of developing MS in twins.

Diagnosis of Enteroviral Meningitis by Use of Polymerase Chain Reaction of Cerebrospinal Fluid, Stool, and Serum Specimens

BACKGROUND

Because enteroviruses can be detected in various clinical samples during enteroviral meningitis, we analyzed the combined diagnostic utility of polymerase chain reaction (PCR) of cerebrospinal fluid (CSF), feces, and serum for detection of enterovirus in specimens obtained from adults with aseptic meningitis or encephalitis.

METHODS

PCR results were analyzed for 34 adults for whom enteroviral meningitis was diagnosed on the basis of virus isolation and antibody detection in our hospital during 1999-2003. PCR results were also analyzed for 77 adults with meningitis or encephalitis of another defined cause for whom this assay was used for diagnostic evaluation during that period.

RESULTS

Twenty-six (76%) of 34 CSF samples and 24 (96%) of 25 fecal samples collected from patients with enteroviral meningitis had positive PCR results. The diagnostic yield of the test was lower for CSF specimens obtained >2 days after clinical onset, compared with CSF collected < or =2 days after onset. Instead, PCR of feces was highly useful also later, because 12 of the 13 fecal specimens obtained 5-16 days after clinical onset had positive test results. None of 75 CSF samples and 2 of 48 fecal samples obtained from patients with nonenteroviral infection had positive PCR results. All serum samples were PCR negative.

CONCLUSIONS

PCR of fecal specimens obtained throughout the course of enteroviral meningitis had the highest clinical sensitivity for detecting enterovirus. It is recommended that, in addition to performance of CSF PCR, fecal samples collected from patients with suspected enteroviral meningitis should be tested by PCR, especially when the duration of symptoms is >2 days.

Production d’interféron alpha dans le sérum des très jeunes nourrissons lors d’infections virales

IFN-alpha detection is useful in some clinical circumstances, but its use has never been validated in young infants with viral infections.

OBJECTIVE

The authors wanted to determine it there was any difference in the assessment of IFN-alpha production between infants under or over six months of age.

PATIENTS AND METHOD

A series of 233 children with identified common viral infections who had been assessed for IFN-alpha production was retrospectively analyzed. The viral infections were enteroviral meningitis (n =103), respiratory syncytial virus infections (n =60), and rotavirus gastroenteritis (n =70). Data collected from the group of infants under six months of age (n =105) was compared to that of the older children (n =128). Qualitative and quantitative values of interferon-alpha were determined for each group.

RESULTS

Interferon-alpha was detected in very young infants (81.9% of cases) as often as in the older age group (80.3% of cases), for any of the three viral infections (P =0.3-0.63). The mean level of interferon-alpha production detected was not lower in the youngest group, and even higher in the group under six months of age with enteroviral meningitis.

CONCLUSION

Interferon-alpha detection in very young infants is efficient and may be useful to differentiate between viral and bacterial infection particularly when the etiological diagnosis appears uncertain.

Endothelium-Dependent Flow-Mediated Vasodilation of Systemic Arteries Is Impaired in Patients With Myocardial Virus Persistence

Background— Myocardial virus persistence is frequently observed in patients with cardiomyopathy. Endothelial dysfunction in patients with cardiomyopathy is associated with inflammatory immunoresponses in myocardial biopsies. The aim of this study was to investigate the impact of myocardial virus persistence on endothelial function.

Methods and Results— In 124 patients with suspected cardiomyopathy, myocardial biopsies were examined for virus persistence (by polymerase chain reaction) and inflammation (by immunohistology). Endothelial function of the radial artery was examined by high-resolution ultrasound. Diameter changes in response to reactive hyperemia (flow-mediated dilation [FMD]) compared with glycerol trinitrate (GTN-MD) were measured. Mean age of the patients (55 men, 69 women) was 45±13 years; ejection fraction was 57±17%. In 73 patients, adenovirus, enterovirus, parvovirus, or HHV6 virus (V) was detected; in 51, no virus was detected. FMD was significantly impaired in patients with myocardial virus persistence compared with control subjects (Co): FMD-V, 3.38±2.67%; FMD-Co, 7.34±3.44 ( P <0.001). In 86 patients, myocardial inflammation was confirmed (Inf). Of those, 57 had virus, and 29 did not. FMD was significantly impaired in patients with virus compared with controls: FMD-Inf-V, 3.24±2.66%; FMD-Inf-Co, 6.07±3.00 ( P <0.001). In 38 patients, immunohistology of the myocardial biopsies was normal (Co); of those, 16 had virus, and 22 did not. FMD was impaired in patients with virus compared with control subjects: FMD-Co-V, 3.88±2.72%; FMD-Co-Co, 9.00±3.32% ( P <0.001). Endothelium-independent vasodilation (GTN-MD) was not significantly affected.

Conclusions— Myocardial virus persistence is associated with endothelial dysfunction. Endothelial dysfunction in patients with myocardial virus persistence can occur independently of endothelial activation or myocardial inflammation but is more pronounced in patients with concurrent inflammation.

Correlation between serum estradiol in the follicular phase of the ovarian cycle and decay acceleration factor (DAF) expression on red blood cells and coxsackiervirus B-3 induced hemagglutination in young cycling women

Decay accelerating factor (DAF) is a widely distributed glycoprotein which aids in the inactivation of complement. DAF is also a cellular receptor for certain group B coxsackieviruses (CVB) and is responsible for the viral hemagglutinating activity for human red blood cells (RBC). Healthy, young female volunteers donated blood on days 11 and 22 of the ovarian cycle. Samples were categorized into luteal and follicular phases based on serum progesterone level (P4 either < 2.0 ng/mL, follicular; P4 > or = 2.0 ng/mL, luteal) and analyzed by flow cytomtery for DAF expression on RBC and CD21 + B lymphocytes. Cycling females showed significant variation in CVB-induced hemagglutination and % RBC or CD19 + cells which were DAF +. There was a strong correlation between serum estradiol levels and % RBC expressing DAF (P < 0.01) in the follicular, but not in the luteal ovarian phase. Infection of white blood cells with green-fluorescent protein CVB (GFP-CVB) showed a correlation between infectivity of CD19+ cells and DAF expression. This indicates that women may show differential susceptibility to CVB infection in the luteal and follicular phases of the ovarian cycle.

Coxsackie B virus serology and Type 1 diabetes mellitus: a systematic review of published case-control studies

BACKGROUND

Enteroviruses, in particular Coxsackie B4, have been implicated in the aetiology of Type 1 diabetes mellitus, but the epidemiological evidence has not been systematically evaluated.

METHODS

Systematic review of evidence from published controlled studies of the relationship between Coxsackie B virus serology and incident or prevalent Type 1 diabetes mellitus. Studies were identified through a Medline search (1966 to 2002), supplemented by references from identified papers and hand search of relevant journals. All studies (full papers, abstracts or letters) with data adequate for calculation of unadjusted odds ratios (with 95% confidence intervals) for Type 1 diabetes mellitus in relation to Coxsackie B virus serology were included.

RESULTS

The review included 26 case-control studies; no cohort study met the inclusion criteria. Odds ratios for Type 1 diabetes mellitus in serology-positive vs. serology-negative subjects ranged from 0.2 to 22.3. For Coxsackie B (any serotype) 7/13 studies had point estimates significantly greater than 1.0 (P < 0.05). For Coxsackie B3, Coxsackie B4 and Coxsackie B5-specific assays, 1/11, 6/17 and 1/11 studies, respectively, had point estimates significantly greater than 1.0. Summary odds ratios were not calculated because of doubts about the validity of individual study estimates, heterogeneity between studies, and the possibility of publication bias.

CONCLUSIONS

The results of these studies are inconsistent and do not provide convincing evidence for or against an association between Coxsackie B virus infection and Type 1 diabetes mellitus. Better designed studies using effective assays are needed to resolve this important issue.

[Laboratory diagnostics of enterovirus cardiac infections]

Diagnostic efficacy of different markers of enterovirus cardiac infection (EVCI) has been evaluated. Testing of clinical samples from patients with myocarditis (n=50), dilatation cardiomyopathy (n=122), ischemic heart disease (n=34) and from healthy donors (n=50) revealed diagnostically significant markers in patients suspected for enterovirus cardiac infection: antienterovirus IgM in the patient's blood serum, the expression of viral proteins by myocardium cells and the presence of genome RNA and replicative intermediate in cardiac cells. The results obtained were used for developing up-to-date scheme of the EVCI diagnosis which included the data from the case history, the preliminary rapid diagnosis and the molecular biological study of the cardiac biopsies.

Myocarditis: an expected health hazard associated with water resources contaminated with Coxsackie viruses type B

Enteroviruses, especially Coxsackie B viruses (CBVs), are responsible for approximately 50% of cases of viral myocarditis. In the present study, serum samples (160) were collected from acute myocarditis patients at different age groups and 104 samples of the same age groups as a control. Cholesterol, LDH, CPK, and GOT were measured for all serum samples (264). Also, to study the source of virus transmission, 72 water and 72 wastewater samples were collected from water and wastewater treatment plants at intakes and outlets. Water and wastewater samples were concentrated by filtration through Zeta-plus filter cartridges and reconcentrated by the PEG-6000 precipitation method. Serum, water, and wastewater samples were inoculated in BGM cells for three successive passages. RT-PCR with enterovirus primers was carried out directly for serum samples and for 1st and 3rd cell culture passages. The positive samples were used for neutralization assay using anti-CBV sera pool to determine the CBV followed by neutralization with separate antisera. The results showed that 50 (31.25%) serum samples from acute myocarditis patients and two (1.4%) samples from the controls were positive for enterovirus RT-PCR. For water and wastewater samples enteroviruses were present in 63.8% and 8.3% for intake and outlet of water treatment plants and, 66.6% and 47.2% for intake and outlet of wastewater treatment plants, respectively. The level of CBV serotypes was varied where CBV3 was dominant for all age groups of myocarditis patients and CBV2 and CBV5 were also detected while CBV2 was the main CBV in water samples and CBV2, 3 and 5 were detected in wastewater samples. The integration of cell culture-PCR reduces the time required for virus detection and enhances the sensitivity of the test.

Frequency, viral loads, and serotype identification of enterovirus infections in Scottish blood donors

BACKGROUND

Enteroviruses are non-enveloped, frequently pathogenic RNA viruses infecting humans. Infection is potentially transmissible through blood or blood component transfusion from donor in the viremic phase before seroconversion for antibody. To investigate the threat to blood safety from enteroviruses, a large-scale survey of frequency and levels of viremia in blood donors was conducted.

STUDY DESIGNS AND METHODS

Blood donations from Scotland over a period of 22 calendar months were screened for enterovirus RNA sequences by PCR. Positive samples were quantified, and serotypes were identified by nucleotide sequencing of VP1.

RESULTS

From a total of 3658 pools of 95 donations tested, 73 samples that were enterovirus-positive were identified (corrected annual frequency 0.024% or 1 in 4000). The highest rates of viremia were in late summer months (e.g., 0.055%, 1 in 1800 in July) and lowest from January to May (0.009 and 0.012%). Viral loads ranged from 500 (the lower cutoff of the assay) to greater than 100,000 amplifiable enterovirus template copies per mL. Coxsackievirus A16, echoviruses 11 and 30, and enterovirus 71 were most often identified.

CONCLUSIONS

The detection of enterovirus-positive blood units indicates the potential for enteroviral transmission by blood components. Although the infrastructure established for PCR-based screening for HCV RNA would allow parallel screening for enteroviruses, any decision concerning donor testing would require further information on the outcome of transfusion-acquired enterovirus infections.

Determination of enterovirus serotype inferred from sequence analysis of PCR products

BACKGROUND

Enterovirus infections are common in neonates. Virus isolation is the only diagnostic method to confirm enterovirus serotype infections, however, is not always successful.

OBJECTIVES

A new approach for the diagnosis of enterovirus infections was performed, using the reference strain inferred from sequence analysis of PCR products.

STUDY DESIGN

Virus isolation, enterovirus RT-PCR and sequence analysis were performed from clinical samples or stored sera from two neonates with fever and rash. Neutralizing test (NT) antibodies against prototype reference virus were measured in paired sera.

RESULTS

Virus isolation was negative in both patients but the enterovirus genome was amplified in the acute phase sera obtained from the two patients. From the results of sequence analysis of 109 nucleotides located in the 5'-noncoding of the conserved region of enteroviruses, a high homology to echovirus types 25 and 30 was found. More than a 4-fold increase in NT antibodies against reference viruses was demonstrated in the acute and convalescent phase sera. They were confirmed as echovirus type 25 and 30 infection, respectively.

CONCLUSIONS

These virological examinations are practical and useful for clinical settings for a diagnosis of enterovirus infections because of an insufficient positive rate in virus isolation.

Proinflammatory cytokine reactions in enterovirus 71 infections of the central nervous system

Enterovirus 71 (EV71) infection can lead to devastating clinical outcomes. An appreciation of the scientific relationship between cytokine response and patient mortality may help limit the risks posed by this deadly illness. We present the results of a study that compared the cerebrospinal fluid (CSF) and serum levels of interleukin-6 (IL-6) and interleukin-1beta (IL-1beta) in 24 patients with EV71 infection. Cases in this study involved diverse manifestations or complications, including encephalitis, poliomyelitis-like syndrome, meningitis, and pulmonary edema. CSF levels of IL-6 in study patients were found to be consistently higher during the first 2 days of central nervous system (CNS) involvement than afterward. Compared with patients who did not have pulmonary edema, patients who experienced pulmonary edema had dramatically varied blood values, including IL-6, white blood cell counts, and glucose levels. Our findings suggest that the combination of CNS and systemic inflammatory response may trigger EV71-related cardiopulmonary collapse.

Responses of IgM for enterovirus 71 infection

A rapid serological assay was developed for detection of specific IgM to enterovirus 71, a human picornavirus that is usually associated with severe central nervous system complications. The sensitivity and specificity of this "in-house" mu-capture enzyme linked-immunosorbent assay was assessed by testing 213 serum samples. With the conventional virus culture as a standard method, the sensitivity and specificity were 91.5 and 93.1%, respectively, for this newly developed immunoassay. This method allows for detection of the IgM responses from the patients either infected by genotype B or genotype C of enterovirus 71. IgM can be detected as early as the second day from the onset of disease. IgM responses exhibit 100% positive rate from enterovirus 71-infected patients with complications, including encephalitis, meningitis, polio-like syndrome, pulmonary edema, and fatal cases. These findings suggest that detection of specific IgM by the use of enzyme linked-immunosorbent assay is a rapid and valuable way for the diagnosis of enterovirus 71 infection.