摘要:

AbstractPuumala virus (PUU) is a member of theHantavi rusgenus in the familyBunyaviridaeand the etiologic agent of nephropathia epidemica (NE), a form of haemorrhagic fever with renal syndrome (HFRS). In this study we compared the immunofluorescence patterns of NE sera and antibodies raised against recombinant PUU proteins and confirm that the nucleocapsid protein is the major target in the early IgG response of NE patients and provides the molecular basis for simple and rapid differentiation between acute illness and old immunity by granular vs. diffuse fluorescence staining in the indirect immunofluorescence test. The differential kinetics of B‐cell responses to PUU nucleocapsid vs. envelope proteins was emphasized further by the end‐point titres of IgG antibodies to N, G1 and G2 proteins in NE patients. The granular fluorescence correlated with low IgG avidity in 99.8%. and diffuse fluorescence with high avidity in 100% of 617 NE sera studied. Epitope scanning with overlapping 14‐mer peptides covering the whole nucleocapsid protein by a shift of 3 amino acids revealed six major antigenic epitopes recognized by sera from acute‐phase NE patients. The epitopes clustered mainly in the hydrophilic regions, and two of them in a highly variable region which could probably serve as an antigen to distinguish serologically between infections of closely related hantaviruses, some apparently apathogenic, some causing lethal infections. The anti‐peptide epitope pattern varied between different individuals and a collection of several pinbound peptides was needed to be recognised by most NE sera studied. © 1995 Wiley

ISSN:0146-6615    

DOI:10.1002/jmv.1890460402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractA one‐stage polymerase chain reaction (PCR) followed by an automated liquid hybridisation assay was used to examine anti‐HCV‐positive patients. The presence of HCV‐RNA in 251 randomly selected enzyme immunoassay (EIA) positive clinical specimens was compared to their RIBA pattern. An association of a RIBA pattern with presence or absence of HCV‐RNA was not detected. One hundred of these samples were also evaluated after dividing them into normal and elevated serum alanin aminotransferase (ALT) levels. PCR results were obtained on the basis of amplification products from two different gene regions (5′‐NC region and NS 3). To prove the specificity of the PCR products, a commercially available digoxigenin‐based liquid hybridisation assay was evaluated. The sensitivity was comparable to the results obtained after nested PCR. Based on the results of the study, the two‐stage PCR can be changed in favour of the easier one‐step PCR which offers the advantage of fewer contamination problems. ©

ISSN:0146-6615    

DOI:10.1002/jmv.1890460403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractCoxsackie B enteroviruses have been implicated repeatedly as agents associated with chronic fatigue syndrome (CFS). The objective of this study was to compare the serological evidence for the presence of Coxsackie B virus neutralising antibody, with the polymerase chain reaction (PCR) detecting a portion of the 5′ nontranslated region (NTR) of the enterovirus genome. Serum samples from 100 chronic fatigue patients and from 100 healthy comparison patients were used in this study. In the CFS study group, 42% patients were positive for enteroviral sequences by PCR, compared to only 9% of the comparison group. Using the neutralisation assay, 34% of study patients were positive, compared to 41% of comparison patients. In the study group, 66/100 patient results correlated, i.e., they were either positive/positive or negative/negative for both tests. Of those that did not correlate, the majority were PCR‐positive/Coxsackie B antibody‐negative (21/34). In the comparison group, 58/100 patient results correlated. Of those that did not, the majority were PCR‐negative/Coxsackie B antibody‐positive (37/42). The Coxsackie B antibody neutralisation assay was not able to differentiate the CFS study group from the healthy comparison group, and thus the clinical relevance of this assay may be questioned. The PCR assay did differentiate the two groups with significantly more CFS patients having evidence of enterovirus than the comparison group. © 1995 Wiley

ISSN:0146-6615    

DOI:10.1002/jmv.1890460404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractRecently, it was demonstrated in chronic hepatitis C that the release of IgG and IgM anti‐HCV antibodies by mononuclear cells (PBMCs) correlated with inflammatory activity, HCV persistence in serum, and negative outcome from antiviral therapy. Thus, persistent antigenic stimulation of the antibody‐secreting B cells has been suggested. In this study, PBMCs were derived from 13 patients with chronic hepatitis C. Nucleic acids were extracted by the guanidine‐thiocy‐anate‐method, and plus‐ and minus‐stranded HCV‐RNAs were determined using primers from the 5′‐untranslated region of HCV. Simultaneously, unstimulated PBMCs were cultured for 8 days and anti‐HCV antibodies were detected in the supernatants by EIA and RIBA.Seven patients (53.8%) had both plus‐ and minus‐stranded HCV‐RNA in PBMCs, while anti‐HCV antibodies were secreted in vitro. One of 2 patients with plus‐ but not minus‐stranded HCV‐ RNA in PBMCs was anti‐HCV positive in vitro, whereas 4 patients without HCV‐infected PBMCs were anti‐HCV negative in vitro.Eight patients received antiviral therapy with interferon‐α2b. Four nonresponders and 1 partial responder had plus‐ and minus‐stranded HCV‐ RNA in PBMCs and anti‐HCV secretion in vitro. On the other hand, 2 complete responders and another partial responder showed neither HCV infection of PBMCs nor anti‐HCV secretion in vitro.In conclusion, infection of PBMCs by HCV is observed frequently in patients with chronic hepatitis C, and may be related to the high rate of nonresponders to antiviral treatment. The close correlation of anti‐HCV secretion in vitro and viral replication suggests that the humoral response to HCV is triggered by viral antigens that are express

ISSN:0146-6615    

DOI:10.1002/jmv.1890460405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractFetal infection with human cytomegalovirus (HCMV) is the leading viral cause of brain dam age among newborns at birth or later in life. Efforts to screen newborns routinely for shedding of the virus by immunoassay have been ham pered by inhibitors in urine, reportedly the host protein beta2‐microglobulin (β2m). An enzyme‐linked immunosorbent assay (ELISA) was devel oped for the detection of HCMV antigen in which the reactivity was not affected by the presence of β2m, but nevertheless inhibition was observed when urine samples with high levels of virus were tested. The presence of antibodies to HCMV was demonstrated in these urine samples by antibody ELISA and immunoblot using the major antigenic protein of HCMV (pp150) expressed inEscherichia coli; this offers an alterna tive explanation for the inhibition in ELISA. The presence of HCMV antibodies correlated significantly with congenital HCMV infection (as detected by tissue culture isolation of virus from urine samples of newborns), especially with as ymptomatic cases (sensitivity 70%; specificity 94%). The data indicate a local (renal) immune response to HCMV in congenitally infected children, which may have future diagnostic applica tions. © 1995 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of

ISSN:0146-6615    

DOI:10.1002/jmv.1890460406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe results of hepatitis C virus (HCV) antibody test of 237, 813 blood donations collected from 143, 815 donors by the West Midlands Blood Transfusion Centre in 1993 were analyzed retrospectively in order to determine the seroconversion rate among established previously anti‐HCV negative donors. Three hundred sixteen (0.22%; 1 in 455) donors were positive by the enzyme linked immunosorbent assay (ELISA) screening test and 34 (0.024%; 1 in 4, 230) donors were positive by ELISA and the Recombinant Immuno Blot Assay (RIBA). Three donors previously negative for HCV antibody reacted positively by both tests. The annual seroconversion rate was calculated as one in 35, 937 donors. This figure argues against limitation of HCV antibody screening to new blood donors. A further 45 donors negative on previous screening reacted positively by ELISA and were indeterminate by RIBA. Unexpectedly, lapsed blood donors first tested for HCV antibody in 1993 had high positive reaction rates by ELSA and RIBA, which was significantly (P<0.001) higher than those of new donors. RIBA‐positive reaction rate among ELISA‐positive donors was significantly higher amongst males than females (P<0.0011. © 1995 Wiley‐L

ISSN:0146-6615    

DOI:10.1002/jmv.1890460407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractAmong 39, 656 voluntary blood donors in Okinawa Prefecture, Japan, 115 (0.29%) were repeatedly reactive for antibody to hepatitis C virus (anti‐HCV) by second generation (2nd‐gen) passive hemagglutination assay (PHA). Positive serum samples were tested for anti‐HCV using three different enzyme immunosorbent assays (ELISAs; Abbott 2nd EIA, UBI‐HCV‐EIA, JCC‐2) and for HCV‐RNA by the polymerase chain reaction (PCR).The 115 2nd‐gen PHA‐positive sera were divided into three groups according to the agglutination titers;>210(high titer group), 27−29(median), 25−26(low). All but one serum (44/45) in the high PHA titer group reacted in each of the three second screening ELISAs. Furthermore, 43 (97.7%) of the 44 sera contained HCV‐RNA by PCR. In the median titer group, 11 of the 13 samples tested were positive by each of the three ELSIAs, and 4 (36.4%) of the 11 showed reaction by PCR. On the other hand, all of the 38 sera tested in the low titer group were negative for HCV‐RNA by PCR, and 24 of the 38 were also negative by each of the three ELISAs.Most of the low titer positive reactions in the 2nd‐gen agglutination assay seemed to be false positive. In Okinawa Prefecture, the prevalence of anti‐HCV among blood donors is much lower than in the rest of Japan (0.29% vs. 1.11%). Moreover, a significant proportion of these sera were low titer by the PHA assay. The difference in the genuine anti‐HCV‐positive rate, or the prevalence of HCV carriage between Okinawa Prefecture and the rest of Japan may therefore be even greater than is presentl

ISSN:0146-6615    

DOI:10.1002/jmv.1890460408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe genomes of 477 Japanese strains of molluscum contagiosum virus (MCV) were analyzed using an in‐gel digestion method with the restriction enzymeBamHI, and classified into four types, including a newly detected type (MCV type 4). All type 1 (MCV‐1) genomes examined so far in Japan showed a common difference from the genome of the MCV‐1 prototype (MCV‐l p), the type reported to be most prevalent in Europe. The common markers of the variants of MCV‐1 were 24‐kbp fusion fragments generated by the loss of aBamHl site between the D2 and F fragments of MCV‐1 p. These variants of MCV‐1 were classified into three groups (MCV‐lva, MCV‐1vb, MCV‐l vc), with the variability among them being due to additions and losses ofBamHl sites located in the right terminus and around the Eand I fragments of MCV‐lva. The restriction map of MCVB was generated and lined up with those of the other types. Cross‐hybridization analysis revealed that the organization of all types of MCV genomes were essentially colinear. Considerable numbers ofBamHl restriction sites were conserved between MCV‐2 and 4, indicating a close analogy between them. The overall prevalence of MCV, as shown by the ratios of MCV‐1 (MCV‐1p):MCV‐2:MCV‐3:MCV‐4, was 436(0):13: 24:4. Thus, the molecular epidemiology of MCV in Japan is characterized by the absence of the European prototype of MCV‐1, the exclusive occurrence and abundance of variants of MCV‐1, a greater prevalence of MCV‐3 over MCV‐2, and

ISSN:0146-6615    

DOI:10.1002/jmv.1890460409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractStudies on the antibody responses to various Epstein‐Barr virus (EBV) antigens have been instrumental in the understanding of the seroepidemiology and diagnosis of this viral infection and the subsequent carrier state. While antibodies to the viral capsid antigen (VCA), early antigen (EA), and nuclear antigens 1 and 2 (EBNA 1 and 2) have been well characterized, the antibody response to the other nuclear antigens is not well understood. EBNA 6 is expressed by lymphoblasts during acute EBV infection and may be an important antigen for diagnosis and evaluation of the immune response. In order to analyze the antibody response to EBNA 6, ten peptides (20–21 amino acids), deduced from the EBNA 6 coding region, were synthesized and evaluated for antigenicity by ELISA. One peptide (p‐63; PA‐PQAPYQGYQEPPAPQAPY) derived from the amino acid repeats showed the highest specific reactivity with human sera. This peptide was evaluated further for detection of human EBNA 6‐reactive antibodies. Forty‐two of forty‐nine (86%) EBV‐seropositive healthy donors had p‐63‐ specific IgG reactivity, while none of 50 EBV seronegative patients reacted with the p‐63 peptide. Twenty‐two of fifty‐one (43%) patients with ongoing primary EBV infection had detectable p‐63‐specific IgG. Serum samples drawn sequentially from patients during and after primary EBV infection revealed an increase in p‐63‐reactive IgG over time. A similar pattern was found for reactivity with an EBNA I‐specific peptide (p‐107), in contrast to the EBNA 2 (polyproline) response, which decreased over time. Some EBV seropositive individuals who had no detectable IgG against peptide p‐63 did have antibodies against the native EBNA 6 by anticomplement immunofluorescence to EBNA 6 transfected cells. Rabbit antiserum raised against p‐63 reacted specifically with native EBNA 6 by an immunofluorescence assay and by immunoblotting, indicating the EBNA 6‐specific antigenicity of the peptide. Thus, the peptide p‐63 derived from the amino acid repeats of the EBNA 6 coding region constitutes a predominant, although not exclusive, epitope in the EBN

ISSN:0146-6615    

DOI:10.1002/jmv.1890460410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe aim of this study was to determine if rhesus monkeys infected with one isolate of hepatitis E virus (HEV) were immune to subsequent challenge with other isolates of the virus. Three epidemic and one sporadic Indian HEV isolates were employed in the study. The interval between primary inoculation and challenge varied from 1 year and 6 months to 2 years and 9 months. Evidence of HEV infection was ascertained by rise in serum alanine transaminase (ALT) levels and/or seroconversion to antibodies to HEV (anti‐HEV), and the presence of HEV‐RNA in the bile or faeces of the infected monkeys. No evidence for multiplication of virus in monkeys challenged with different HEV isolates was obtained. These results show that immunity generated by one isolate of HEV protects against different isolates of hepatitis E virus. © 1995 Wiley‐Lis

ISSN:0146-6615    

DOI:10.1002/jmv.1890460411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY