化学发光酶免疫分析法在乙肝病毒及核心抗体定性检测中的应用分析

目的 通过对比,探讨了化学发光酶免疫分析法在乙肝病毒及核心抗体定性检测中的应用价值.方法 选取2013年5月至2015年5月在我院的疑似乙型肝炎患者80例,抽取空腹血液样本后都分别进行乙肝病毒以及核心抗体的化学发光酶免疫分析法及ELISA法检测,并对其检测结果进行分析.结果 化学发光酶免疫分析法检出乙型肝炎病毒阳性78例,检出率为97.5％;而ELISA检出乙型肝炎病毒阳性76例,检出率为95.0％,两种方法的检出率对比差异无统计学意义(P＞0.05).化学发光酶免疫分析法对于乙肝病毒核心抗体IgM与IgG的检测阳性率分别为80.0％和70.0％,而ELISA法检测两种抗体的阳性率则分别为18.8％和20.0％,化学发光酶免疫分析法对乙肝核心抗体IgM与IgG的检测阳性率明显高于ELISA法(P＜0.05).ELISA法检出HBc-IgM的最低限为0.135 IU/ml,检出HBc-IgM最低限为0.143 IU/ml;化学发光酶免疫分析法检出HBc-IgM最低限为0.032 IU/ml,检出HBc-IgG最低限为0.038 IU/ml.结论 化学发光酶免疫分析法在乙型肝炎检测中具有高的检出率,尤其对乙肝病毒的核心抗体的检测敏感度较高,值得在临床推广应用.     

Morphology of hepatitis C and hepatitis B virus particles as detected by immunogold electron microscopy

We performed indirect immunogold electron microscopy (EM) for immunological identification and characterization of hepatitis C virus (HCV). To clarify the morphology of HCV, an indirect immunogold EM of two plasma samples from patients with high HCV RNA titers was carried out using antibodies specific for the putative HCV envelope protein (E) 1. Spherical virus particles 55–65 nm in diameter with delicate spike projections were detected in the 1.14–1.16 g/ml fractions after sucrose density gradient centrifugation. Polyclonal and monoclonal antibodies to the putative HCV E1 specifically recognized these particles. In addition, immunogold EM of the samples was also performed to uncover the morphology of HCV core particles. Spherical particles 33–40 nm in diameter (average, 37 nm) were detected in the 1.22- to 1.25-g/ml fractions by conventional EM after sucrose density gradient centrifugation. Immunogold EM using rabbit polyclonal antibody (RR8) specific for the putative HCV core protein and colloidal gold-labeled goat antirabbit IgG showed binding of the gold particles with RR8. Some of the HCV core particles showed icosahedric morphology. Optical rotation technique showed that the HCV core particles exhibit sixfold symmetry and that the length of the regular hexagon side is approximately 20 nm, suggesting that they have an icosahedric structure. Further, the detection limit of the indirect immunogold EM was evaluated in 11 plasma samples from chronic hepatitis B patients with different degrees of hepatitis B virus (HBV) DNA titers using antihepatitis B surface antigen antibody. The study showed that the detection limit of virus using this method is 10⁷ virions/ml.     

Vaccination against hepatitis B virus at the Lyon Pasteur Institute. A seven-year evaluation]

Results of immunization against hepatitis B among Pasteur Institute staff members are reported. Prior to immunization, 439 subjects were tested for hepatitis B virus (HBV) markers, including HBs antigen, anti-HBs antibody, and anti-HBc antibody (Ausria, Ausab, Corab assays; Abbott). Forty-seven subjects tested positive for anti-HBs antibody. 317 subjects negative for all the HBs markers studied were given three intramuscular doses of Hevac B (Pasteur vaccins) at one-month intervals. Anti-HBs antibodies were assayed after the third injection with the following results: mean titer, 1,454 mIU/ml, standard deviation, 5,349 mIU/ml, and range, 4 to 41,100 mIU/ml. Anti-HBs titers above 10 mIU/ml were found in 879.4% of subjects. Non-responders and weak responders (anti-HBs titer under 10 mIU/ml) were given a fourth dose of vaccine. Ultimately, after the last (third of fourth) injection 97.6% of subjects had protective antibody titers. No case of HBV infection was seen during the seven-year follow-up period.     

Impaired humoral response to vaccines among HIV-exposed uninfected infants

Little is known about the vaccine protective response for infants born from HIV-infected mothers. We evaluated the antibody response to hepatitis B, tetanus, and diphtheria vaccine in vertically HIV-exposed uninfected infants and compared them to those of control infants not exposed to the virus. The quantitative determination of specific neutralizing antibodies against hepatitis B, diphtheria, and tetanus were performed blindly on serum samples. The results showed that 6.7% of the HIV-exposed uninfected individuals were nonresponders to hepatitis B vaccine (anti-HBs titer, <10 mIU/ml), and 64.4% were very good responders (anti-HBs titer, ≥1,000 mIU/ml), whereas only 3.6% of the nonexposed infants were nonresponders (χ(2)=10.93; 1 df). The HIV-exposed uninfected infants showed protective titers for diphtheria and tetanus but lower geometric mean anti-tetanus titers compared to those of the HIV-unexposed infants. Our data point to the necessity of evaluating vaccine immune responses in these children and reinforced that alterations in lymphocyte numbers and functions reported for newborns from HIV-infected mothers interfere with the vaccine response.     

Screening for Hepatitis B Virus DNA in Serum of Organ Donors and Renal Transplant Recipients

In order to determine the impact of screening potential organ donors for hepatitis B virus DNA using a standardized test, the serum of 145 donor candidates was tested. All of the candidates were negative for hepatitis B virus DNA, but the status of one donor was doubtful for hepatitis B virus surface antigen and seven donors tested positive for hepatitis B virus core antibody without hepatitis B virus surface antigen. Nine transplant recipients tested positive for hepatitis B virus surface antibody; they were given kidneys from the donor with a doubtful hepatitis B virus surface antigen result and from four of the seven donors who tested positive for hepatitis B core antibody. Follow-up revealed no case of hepatitis B transmission. In this study, screening for hepatitis B virus DNA was useful and did not lead to donor organ shortage. Patients with hepatitis B virus surface antibodies can safely be given kidneys from donors who are positive for hepatitis B core antibody but negative for hepatitis B virus DNA. Electronic Publication     

Interferon as an adjuvant for hepatitis B vaccination in non- and low-responder populations

To determine the effect of interferon on the production of antibodies against hepatitis B virus, recombinantα-interferon was added only to the fifth vaccine injection in a non-responder group and to all three initial vaccine injections in a low-responder group. In the non-responder group, 27 % of the hemodialysis patients, 7 % of the renal transplant patients, and both medical staff members tested developed low serum concentrations of anti-HBs (< 25 mU/ml). Whereas in the low-responder group 60 % of the hemodialysis patients developed the same amount of antibodies as a placebo group of comparable patients (? 25 mU/ml), 78% of the renal transplant patients showed a 25 % higher antibody concentration than a placebo group (half < 25 mU/ml;half < 50 mU/ml). According to these preliminary findingsα-interferon may have an adjuvant effect on hepatitis B vaccination.     

Assay of preS epitopes and preS1 antibody in hepatitis B virus carriers and immune persons

The diagnostical significance of the large hepatitis B surface protein with its preS1 attachment site and of anti-preS antibodies are not yet well known. We investigated the epitope of the preS1 attachment site to see whether it is a marker of viremia and whether antibodies against it occur in convalescents and vaccinees. For comparison, sera were also tested for the presence and relative amount of a preS2 epitope. The epitopes were detected by binding to specific monoclonal antibodies (mAb MA18/7 for the preS1 epitope and mAb Q19/10 for the preS2 epitope) at the solid phase of a sandwich enzyme-linked immunosorbent assay. Antibody against the preS1 epitope was detected by inhibition of binding to mAb MA18/7. This mAb inhibits attachment of preS1 antigen to hepatocytes and reacts with a subtypeindependent sequential epitope at the surface of hepatitis B virus between amino acid 29–36. This preS1 epitope occurs in most hepatitis B surface antigen (HBsAg) carriers, irrespective of viremia. Free preS2 epitope Q19/10 is present in samples with more than 8 g/ml total HBsAg and it is masked in sera with less HBsAg. Antibodies which compete with mAb MA18/7 for its viral preS1 epitope occur in one third of HBsAg carriers who were negative for hepatitis B e antigen. It also occurs in one third of convalescents and in most good responders to plasma-derived vaccines.     

Infection with hepatitis A, B, C, and delta viruses among patients with acute hepatitis in Mongolia

One hundred ten consecutive patients (60 males and 50 females; age, mean +/- standard deviation [SD], 22.6 +/- 6.4 years; range 16-48 years) who were clinically diagnosed with sporadic acute hepatitis between December 2004 and January 2005 in Ulaanbaatar, Mongolia, were studied. IgM antibodies to hepatitis A virus were detected in 18 patients (16.4%), IgM antibodies to hepatitis B core (anti-HBc IgM) in 38 patients (34.5%) including two patients with concurrent hepatitis delta virus (HDV) infection, and hepatitis C virus RNA in nine patients (8.2%). There were 30 hepatitis B virus (HBV) carriers who had detectable hepatitis B surface antigen and antibodies to HDV but were negative for anti-HBc IgM, suggesting that they acquired type D acute hepatitis due to superinfection of HDV on a background of chronic HBV infection. None had IgM antibodies to hepatitis E virus (HEV). Consequently, 16.4, 32.7, 6.4, 1.8, and 27.3% of the patients were diagnosed as having acute hepatitis of type A, B, C, type B + D (HBV/HDV coinfection), and type D (superinfection of HDV), respectively. The cause of hepatitis was not known in the remaining 17 patients (15.5%). All 18 HAV isolates were genotyped as IA, all 9 HCV isolates were genotyped as 1b, and all 32 HDV isolates were classified into genotype I. The distribution of HBV genotypes among the 67 HBV isolates was A (1.5%, n = 1) and D (98.5%, n = 66). The present study indicates that de novo infections of HAV, HBV, HCV, and HDV are prevalent among young adults in Mongolia.     

Determination of immunoglobulin M antibodies for hepatitis B core antigen with a capture enzyme immunoassay and biotin-labeled core antigen produced in Escherichia coli.

A new capture enzyme immunoassay for the determination of immunoglobulin M (IgM) antibodies against hepatitis B core antigen (HBcAg) is described. Core antigen produced in Escherichia coli was labeled with biotin and subsequently detected by an avidin-biotin-peroxidase complex. The biotin-labeled core antigen was effective at concentrations as low as 20 ng/ml. Of 561 serum samples from different groups of patients that were tested, 465 samples were negative for other hepatitis B virus markers and also for anti-HBcAg IgM. Sera from the early stages of hepatitis B infection had high levels of anti-HBcAg IgM, and a clear correlation with the acuteness of the disease was observed in 45 follow-up sera from 23 patients with acute or recent hepatitis B. Sera from 21 patients with past hepatitis B were all negative for anti-HBcAg IgM. Twenty serum samples from chronic carriers of hepatitis B surface antigen showed slightly elevated antibody levels for anti-HBcAg IgM. Ten sera which were positive for anti-HBcAg IgG antibodies and had high levels of rheumatoid factor were negative for anti-HBcAg IgM.     

What is the role of serology for the study of chronic hepatitis B virus infection in the age of molecular biology?

To assess quantitative serology in chronic hepatitis B virus (HBV) infection, testing by novel immunoassays has been carried out on 202 specimens from untreated patients and in 83 samples from 10 patients with chronic hepatitis B treated with lamivudine. Serum samples were assayed for quantitative HBsAg, in comparison with quantitative HBV-DNA, and for anti-HBc IgM and the avidity index (AI) of total anti-HBc antibodies. The AI was high (mean: 0.93 +/- 0.19) in all groups, confirming the consistency of this procedure in chronic HBV infections. A low-level positivity (2-28 Paul-Ehrlich units/ml) for IgM anti-HBc was detectable both in HBeAg-positive and in HBeAg-negative untreated chronic hepatitis cases (mean S/CO values by the Abbott Architect assay: 0.51 +/- 0.12 and 0.48 +/- 0.10, respectively; correlation between assays: r = 0.685), while treated patients (mean: 0.20 +/- 0.15) and inactive carriers (mean: 0.17 +/- 0.21), were generally negative for IgM. The levels of HBsAg (IU/ml) showed a weak correlation with HBV-DNA (IU/ml). A difference in HBsAg levels was found between inactive carriers (1,935 +/- 2,887 IU/ml) and chronic hepatitis B cases, either treated (5,199 +/- 9,259 IU/ml) or untreated (14,596 +/- 15,227 IU/ml). Pre-treatment levels of HBsAg in patients undergoing lamivudine treatment were correlated with a sustained response to therapy over 13-33 months (mean: 27.3) of follow-up: mean HBsAg values were 1,576 + 1,487 IU/ml in five responders and 6,063 + 5,142 in five nonresponders or breakthrough responders (P < 0.05). The availability of standardized quantitative immunoassays for HBsAg and anti-HBc IgM may be considered in addition to quantitative HBV-DNA in the staging and monitoring of chronic HBV infection.     

High Prevalence of GB Virus C/Hepatitis G Virus RNA and Antibodies in Patients Infected with Human Immunodeficiency Virus Type 1

 The prevalence of GB virus C (GBV-C)/ hepatitis G virus (HGV) RNA and antibodies to the structural E2 protein was investigated in a cohort of HIV-1 infected patients. Of 346 individuals, RNA was detected in 143 and E2 antibodies were detected in 73, for an overall prevalence of 62.4%. Intravenous drug use and homosexuality were identified as major transmission risk factors. GBV-C/HGV RNA prevalence was associated with hepatitis B coinfection, whereas antibodies to E2 were associated with older age and lower CD4+ cell counts. GBV-C/HGV infection was frequent in this group of HIV-infected patients and was associated with older age, lower CD4+ cell counts, and the presence of hepatitis B surface antigen.     

Seroprevalence of hepatitis C in human immunodeficiency virus infected patients

Prevalence of antibodies against hepatitis C virus (HCV) was evaluated using Ortho and Abbott HCV Elisa assays and the Abbott EIA Neutralization assay in 150 human immunodeficiency virus (HIV)-seropositive patients and compared with the prevalence of hepatitis B virus (HBV) and hepatitis D virus (HDV) markers. Overall prevalence of hepatitis C virus antibodies was 29.3%; significant variations were seen across human immunodeficiency virus risk factor subgroups: prevalence was 10.2% in homosexual men, 12.0% in bisexual men, 73.5% in intravenous drug users, 13.3% in blood transfusion recipients, and 16.6% in frequent travellers. Seroprevalence was higher in the 20 to 40 year-old age group and in patients stage II or III according to the Center for Disease Control classification. Prevalence of hepatitis B virus and hepatitis D virus markers (75.7% and 17.5% respectively) was analyzed according to hepatitis C virus marker status; patients with HBcAb were more likely to have antibodies against hepatitis C virus than their HBcAb-negative counterparts. Further studies are needed to investigate the influence of coexposure to human immunodeficiency virus and hepatitis C virus on liver lesions. Data from this study show that coinfection or coexposure is common.     

Seroprevalence of hepatitis C virus in haemophiliacs in Jamaica

Haemophilic patients (n = 90) and household contacts (n = 40) were tested for serological markers of hepatitis B virus (HBV), hepatitis C virus (HCV) and elevated serum aminotransferases using commercially prepared reagents. Of the haemophiliacs 41% (37/90) tested positive for antibodies to HCV (anti-HCV); 36% (32/90) antibodies to hepatitis B core antigen (anti-HBc); 54% (49/90) antibodies to hepatitis B surface antigen (anti-HBs) and 2% (2/90) hepatitis B surface antigen. On the other hand, 29% (26/90) of the patients and 90% (36/40) of the household contacts tested negative for all of the viral markers. Anti-HCV positivity in the haemophilic patients correlated positively with anti-HBc (p < 0.025). Increasing age (odds ratio 2.09; p < 0.01), severity of disease (odds ratio 6.2; p < 0.05) and the requirement for transfusion (odds ratio 3.2; p < 0.05) were risk factors for anti-HCV positivity. The presence of anti-HBc (odds ratio 3.8; p < 0.01) and coinfection with HCV and HBV also correlated positively with age (odds ratio 2.5; p < 0.01). The provision of anti-HCV screened donor blood and virally inactivated blood products for treatment of all haemophilic patients are goals that must be achieved.     

Reactivity and immunogenicity of Engerix B, the recombinant DNA vaccine against hepatitis B

A group of 67 health workers with no markers indicating previous hepatitis B infection were vaccinated against hepatitis B with a new DNA recombinant vaccine, Engerix B (commercially manufactured by Smith-Kline-RIT, Belgium). Three injections were given according to the 0-1-6 schedule. One month after the last injection the vaccinees were tested for anti-HBs antibodies by the enzyme-linked assay. Antibody titers equal or less than 10 mIU/ml were found only in three subjects or in 4.5% of them. Titers ranging from 11 to 99 mIU/ml were found in 7 subjects (10.4%), from 100 to 999 mIU/ml in 28 (41.8%) and those equal or more than 1000 mIU/ml in 29 subjects (43.3%). It is inferred that the seroconversion rate is 95.5%. Only one subject did not develop detectable antibodies but three subjects had titers over 10000 mIU/ml. No one developed overt hepatitis B during the trial nor did the high responders experienced inapparent infections. They were tested for anti HBc with negative results. Postvaccinal reactions were mild and almost exclusively local. There were no complications. For its high immunogenicity and acceptable reactogenicity the Engerix B vaccine has a promising future.     

Low prevalence of hepatitis C virus antibodies in chronic liver disease in northwest China

To evaluate the prevalence of hepatitis C virus infection in northwest China, 179 chronic liver disease patients in this area were examined for antibody to hepatitis C virus core protein (anti-HCVcore). This antibody was found in only 5 (14 percent) of 37 chronic non-A, non-B liver disease patients, in 11 (16%) of 67 asymptomatic hepatitis B virus carriers, and in 20 (27%) of 75 chronic hepatitis B patients. High titers of anti-HCVcore (cut off index >2) were observed in 3 (60%), 5 (45%), and 9 (45%) of the anti-HCVcore-positive cases of these groups, respectively. We further investigated the seroprevalence of antibodies to hepatitis B virus in the 37 chronic non-A, non-B liver disease patients. All 5 anti-HCVcore-positive cases were positive for a hepatitis B virus marker, with only 44% (14/32) of the anti-HCVcore-negative patients (P < 0.05). Based on these findings, it is concluded that the prevalence of hepatitis C virus infection in chronic non-A, non-B liver disease is unexpectedly low in northwest China and that hepatitis B and C viruses seem to have a similar mode of infection in that area.     

Detection of immunoglobulin M antibodies to hepatitis A virus by enzyme-linked immunosorbent assay.

An enzyme-linked immunosorbent assay for the detection of immunoglobulin M (IgM) antibodies to hepatitis A virus is described. The test uses the principle of binding of IgM antibodies to anti-IgM-coated microtiter plates to determine whether the IgM antibodies attached have specificities for hepatitis A virus. In three patients with hepatitis type A followed up to 12 months, IgM antibodies to hepatitis A virus could be demonstrated from the onset of illness and during the following 2 to 3 months. When acute-phase sera from 48 patients with acute hepatitis were tested, IgM antibodies to hepatitis A virus could only be demonstrated in 18 patients previously classified as type A, whereas 30 patients with type B and non-A non-B hepatitis were negative. IgM antibodies to hepatitis A virus could not be demonstrated in 108 normal sera nor in 55 sera containing rheumatoid factor. These results indicate that the enzyme-linked immunosorbent assay for IgM antibodies to hepatitis A virus is useful in the serodiagnosis of acute hepatitis type A on a single serum sample taken during the acute phase of illness.     

Antibody persistence and immune memory in adults, 15 years after a three-dose schedule of a combined hepatitis A and B vaccine

A combined hepatitis A and B vaccine is available since 1996. Two separate open‐label primary studies evaluated the immunogenicity and safety of this hepatitis A and B vaccine (720 EI.U of HAV and 20 µg of HBsAg) in 306 healthy subjects aged 17–43 years who received three doses of the vaccine following a 0, 1, and 6 months schedule. These subjects were followed up annually for the next 15 years to evaluate long‐term persistence of anti‐HAV and anti‐HBs antibodies. The subjects whose antibody concentrations fell below the cut‐offs between Year 11 and Year 15 (anti‐HAV: <15 mIU/ml; anti‐HBs: <10 mIU/ml) were offered an additional dose of the appropriate monovalent hepatitis A and/or B vaccine. In subjects who received the additional vaccine dose, a blood sample was collected 1 month after vaccination. At the Year 15 time point, all subjects in Study A and Study B were seropositive for anti‐HAV antibodies and 89.3% and 92.9% of subjects in the respective studies had anti‐HBs antibody concentrations ≥10 mIU/ml. Four subjects (two in each study) received an additional dose of monovalent hepatitis B vaccine and mounted anamnestic responses to vaccination. No vaccine‐related serious adverse events were reported. This study confirms the long‐term immunogenicity of the three‐dose regimen of the combined hepatitis A and B vaccine, as eliciting long‐term persistence of antibodies and immune memory against hepatitis A and B for up to at least 15 years after a primary vaccination. J. Med. Virol. 84:11–17, 2011. © 2011 Wiley Periodicals, Inc.     

Case report: risk of virus infection after accidental blood inoculation from a multi-infected AIDS patient

Infections caused by blood-borne viruses such as hepatitis B and C and the human immunodeficiency virus (HIV) are associated commonly with needlestick injuries, especially in a hospital setting. A prospective investigation was conducted on a medical doctor who suffered an accidental needlestick injury during blood collection from a patient with AIDS. The patient's blood contained 195,000 copies of HIV RNA, 1 × 10(6) IU hepatitis C virus (HCV) RNA, and >10(7) copies of parvovirus B19 DNA per 1 ml plasma. It was positive for cytomegalovirus virus and evidence of a resolved hepatitis B virus (HBV) infection was found. HCV viremia was detected in the physician 15 days later and was not resolved by seroconversion after 57 days. HIV infection was not transmitted, possibly because of the immediate use of anti-HIV prophylactic drugs after exposure. Parvovirus B19 infection was presumably prevented by pre-existing specific antibodies in the patient. Considering that many HIV carriers are coinfected with hepatitis B and C viruses, this case report support the knowledge that the risk of HCV transmission from a patient with AIDS is greater than that of HIV.