An approach for immunodiagnosis of clinical cases of filariasis

In this communication an immunodiagnostic approach has been adopted for detection of antigen and antibody in amicrofilaeamic Mf(-) patients by countercurrent immuno electrophoresis (CCIE) and immunodiffusion (ID). Using Setaria cervi and Immune Complex (IC) antigens, out of fifteen clinical cases the number of positive patients in CCIE were twelve and ten respectively. Sixty percent of the Mf(-) cases were positive in antigen detection against both the homologous and heterologous antibody. In ID nine Mf(-) cases gave precipitin bands against S. cervi antigen while with IC antigens ten patients were positive. In similar experiments, it was found that out of fifteen Mf(-) cases nine and eleven patients were positive in antigen detection against microfilaraemic Mf(+) sera and S. cervi antibody respectively. All the Mf(+) cases were positive in both antibody and antigen detection. From the standpoint of immunodiagnosis the data were analysed by two-way analysis of variance study and a newly developed system using Binomial distribution. The sera from the control group were negative in all the immunodiagnostic tests.     

Australian Antigen and Autoantibodies in Chronic Hepatitis

The sera of 110 patients with chronic hepatitis and adequate controls were examined for antibodies to smooth muscle (S.M.), mitochondria (M.), and for antinuclear factors by the immunofluorescence method, and for Australia (Au(1)) antigen by a modified micro-Ouchterlony immunodiffusion technique. Twelve out of 13 patients with primary biliary cirrhosis had M. antibodies, two had antinuclear factor, and none had Au(1) in their sera. In chronic aggressive hepatitis 23·5% of the sera contained antinuclear factor, 13% S.M. antibodies, 10·5% M. antibodies, and 22% Au(1) antigen. Of the 12 patients with chronic persistent hepatitis, one had antinuclear factor, one S.M. antibodies, and three Au(1) antigen.The most striking finding was a mutual exclusion between Au(1) antigen and M. and S.M. antibodies. None of the 33 patients with one or the other form of chronic hepatitis and M. or S.M. antibodies had Au(1) antigen; 22 out of 77 (28%) patients without such antibodies were positive.     

Reactivities of 4 murine coronavirus antigens with immunized or naturally infected rat sera by enzyme linked immunosorbent assay

Four murine coronavirus antigens, sialodacryoadenitis virus (SDAV) strain TG, Parker's rat coronavirus (PCV) strain 8190, mouse hepatitis virus (MHV) strains S and NuU, were examined for their reactivities to hyperimmunized and naturally infected rat sera by ELISA. With the immunized sera, SDAV and PCV antigens reacted best with respective homologous sera. MHV antigens reacted with all antisera, anti-SDAV, anti-PCV, and anti-MHV-S at approximately the same level, and MHV-S showed a slightly higher reactivity than MHV-NuU. The reactivities of the sera from various colonies to these antigens were in the order--from high to low--of SDAV, MHV-S, MHV-NuU, and PCV. None of sera negative for SDAV antigen reacted positively to the other antigens. Within the sera positive for SDAV, the positivities were in the order of MHV-S, MHV-NuU, and PCV. These results suggested that, although homologous antigens are best to detect SDAV or PCV infection by ELISA, MHV antigen can be used if highly cross-reactive viral strain is selected.     

Evidence for hepatitis C viral infection in patients with primary hepatocellular carcinoma.

In testing for antibodies to the hepatitis C virus (anti-HCV) in 112 patients with primary hepatocellular carcinoma, 10 of 33 white patients (30%) and 15 of 79 Asian patients (19%) had a positive response to the antibody. The antibody profile to individual hepatitis C viral antigens and the presence of circulating hepatitis C viral RNA were determined in the 25 patients. The anti-HCV antibodies most frequently detected were toward the antigens from the core (C22) and NS3 regions. Serum hepatitis C viral RNA was present in 17 of the 25 patients (68%), and these patients tended to have serum levels of alanine and aspartate aminotransferases higher than those patients without viremia (136 +/- 22 U per liter versus 64 +/- 11 U per liter and 161 +/- 26 U per liter versus 79 +/- 14 U per liter, respectively, both P < .05). Of the 15 Asian patients with hepatocellular carcinoma and anti-HCV, 4 (27%) had coexisting hepatitis B surface antigen (HBsAg) and 13 (87%) had antibodies to either hepatitis B core or surface antigen. Of the 10 white patients with anti-HCV, however, only 1 (10%) had hepatitis B virus antibodies (P < .01). Among 4 Asian patients with coexisting anti-HCV and HBsAg, 1 was found to have serum hepatitis B viral DNA and the other 3 had hepatitis C viral RNA. A history of blood transfusion was obtained from 12 of the 25 patients with anti-HCV (48%); 20 (80%) had coexisting cirrhosis. Our findings support the hypothesis that hepatitis C virus is an important etiologic agent in the development of primary hepatocellular carcinoma in both white and Asian patients in the United States.     

Seroepidemiology of hepatitis C virus in Beijing, China

To investigate the seroprevalence of hepatitis C virus (HCV) in China we tested sera from healthy individuals without hepatitis and no history of parenteral blood exposure and from patients admitted to a hepatitis hospital in Beijing. Sera were tested for anti-HCV by first-generation enzyme immunoassay; selected positives were tested with two second-generation EIAs, one utilizing recombinant antigens and the other synthetic peptides. We found anti-HCV with the following frequencies: 10 of 164 (6%) individuals with no disease; 2 of 36 (5.5%) patients with acute non-A non-B hepatitis (NANBH); 26 of 39 (67%) patients with post-transfusion NANBH; 10 of 34 (29%) patients with chronic hepatitis negative for hepatitis B surface antigen (HBsAg); 3 of 30 (10%) patients with chronic HBsAg-positive hepatitis; 0 of 19 patients with acute HBsAg-positive hepatitis. Of 24 repeat-positive sera, 19 were positive by both and 4 by one second-generation tests. We conclude that hepatitis C infection is common in China, that it contributes substantially to the incidence of post-transfusion hepatitis, and that HCV plays a significant role in both acute and chronic hepatitis. Further studies are needed to extend these observations and to define the predominant routes of transmission of HCV in China.     

Australia Antigen and Liver Function Tests Following Infectious Hepatitis—A Study of 111 Patients in Quest of Aids in Blood Donor Screening

An epidemic of infectious hepatitis involving 99 patients and employees of a state mental hospital revealed Australia antigen Au(1) to be absent from the blood of all but one of the subjects when tested at six weeks, three months, nine months and 12 to 18 months after onset of jaundice. The single patient with Au(1) at 12 months had no enzyme abnormality to indicate residual liver disease.If Au(1) is the virus of hepatitis these data would support the concept that persistent or long standing viremia is not a feature of epidemic hepatitis. Moreover, results of this study suggest that the Au(1) test should not be used to establish the absence of a past history of hepatitis in blood donors. These data do not establish the value of the Au(1) test in blood donors with active viremia, but do suggest that of 111 patients with recent hepatitis 1 percent had persistent antigenemia and 4 percent probably had circulating antigen antibody complexes and constituted a potential risk to recipients of their blood. The degree of risk to recipients from transfused blood of post-hepatitis patients without demonstrable Au(1) cannot be assessed.     

Major polypeptide of duck hepatitis B surface antigen particles

The 40- to 50-nm pleomorphic particles found in the sera of domestic Pekin ducks infected with duck hepatitis B virus were purified by rate zonal and isopycnic centrifugation. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic polypeptide analysis of these particles, called duck hepatitis B surface antigen particles, revealed the major component to be a single 17,500-dalton polypeptide. This result is in contrast to polypeptide analyses of the surface antigens of related mammalian viruses, including hepatitis B, in which a major doublet of polypeptides is seen with molecular weights ranging from 23,000 to 29,000. Tryptic maps of 17,500-dalton polypeptide resembled that of the major non-glycosylated polypeptide of the adw subtype of hepatitis B surface antigen. A serological assay for antibody to the purified duck virus particles is also described.     

Detection of hantaviral antibodies among patients with hepatitis of unknown etiology in Japan

Hantaviral antibodies were detected in the sera from patients with hepatic disease of unknown etiology in Japan by several different serological diagnostic methods. A total of 105 sera from diseased patients which were negative to A-G hepatitis virus infections in the Tokyo area were tested. Among them, 3 out of 73 sera from patients with chronic hepatic disease were positive to hantaviral antibody by enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescent antibody assay (IFA) and Western blot analysis (WB). Neutralizing antibody titers of the 3 sera to Seoul virus (SEO) were 4 to 8 times higher than those to Hantaan virus (HTN). However, all of the 32 sera from patients with acute hepatitis were negative for hantaviral antibody. Among the 60 patients with chronic hepatitis in Hokkaido which were serologically negative to B and C hepatitis virus infection, one was positive for hantaviral antibody by ELISA and WB. In contrast, the sera from healthy adults in Japan, 550 from the Honshu and Kyushu regions, and 1,000 from the Hokkaido region, were negative for hantavirus antibody. These results show that hantaviral antibodies are more frequently detected in patients with hepatic disease than in healthy adults. However, the observation that no positive sera were detected from patients with acute hepatitis implies that hantavirus might not be directly related to hepatitis.     

Immune-indian ink method for detection of hepatitis A associated antigen and antibody.

TIndian-ink grains coated with commercial gamma globulin (immune-Indian-ink) were agglutinated by 3 percent of sera from healthy volunteer blood donors; by 4 percent of those from hospital staff in contact with patients suffering from hepatitis; and by 10 percent of those from patients with viral diseases other than hepatitis, In contrast, the rate of positive reactions was 86 percent in the case of sera taken from patients in the acute phase of an illness diagnosed as hepatitis A on the basis of epidemiological and clinical data. Investigation of serum samples taken serially from patients positive in the acute phase of illness revealed that the immune-Indian-ink agglutinating factor does not persist for long in majority of cases. Two months after discharge from the hospital it was present in 18 percent of the patients only. The reaction proved negative when a limited number of cases diagnosed as hepatitis B were investigated. The immune-Indian-ink agglutinating factor was inhibited by all but one of 36 sera taken in the convalescent phase from patients with a diagnosis of hepatitis A. Some sera displaying agglutination with immune-Indian-ink gave a reaction with uncoated Indian-ink, too. Efforts to free the sera from non-specific agglutinating factor by starch-block electrophoresis have led to partial success. Fractionation on Sephadex G-200 columns suggested that in molecular weight (or particle size) the immune-Indian-ink agglutinating factor is smaller than HBsAg and larger than the non-specific agglutinating factor. On the basis of these results it is assumed that the immune-tindian-ink reaction is suitable for detecting an antigen tentatively called IH chi Ag and its antibody (IH chi Ab) specific to hepatitis A.     

Antisperm antibodies in human immunodeficiency virus infection: effects on fertilization and embryonic development

Sera from human immunodeficiency virus (HIV)-infected males (n = 10) and females (n = 5) were analyzed for the presence of antisperm antibodies reacting against sperm-specific antigens. Of the HIV-positive males tested, sera of 40% were positive for human sperm extract (HSE), 70% for protamine, and 70% for fertilization antigen (FA-1) for at least one class of antibodies, compared to sera from HIV-negative males. Of the HIV-positive females tested, sera of 40% were positive for HSE, 30% for protamine, and 30% for FA-1 compared to sera from HIV-negative females. The majority of the sperm antigen-reactive antibodies belonged to the IgG class. The reactions observed with FA-1 were weaker than those with other antigens. Ninety percent of HIV-positive male sera and 80% of the HIV-negative female sera were found to contain immune complexes, 20% of which showed the presence of FA-1. HIV-positive male or female sera did not bind to any specific protein on the Western blot of HSE. The minimal amount of free anti-FA-1 antibodies present in sera did not bind to live sperm in the sperm immobilization technique, sperm agglutination technique, or immunobead binding technique and thus were incapable of affecting human sperm penetration of zona-free hamster ova (SPA). Nor did HIV-positive sera induce any apparent abnormality in the development of 2-cell embryos to blastocysts in vitro in murine bioassay. In conclusion, these results indicate that HIV-infected patients have sperm-specific antibodies in their sera that do not adversely affect SPA and murine embryo bioassay. There was a high incidence of immune complex formation after HIV infection. These data will provide the basis for exploring further the role of sperm antigens in altering the immunoregulatory mechanisms after HIV infection.     

IgM antibody against hepatitis B core antigen (IgM anti-HBc): diagnostic and prognostic significance in acute HBsAg positive hepatitis.

IgM antibody against hepatitis B core antigen (IgM anti-HBc), a marker of recent hepatitis B virus infection, was sought by radioimmunoassay in sera diluted 1/4000 from 376 patients presenting to four centres in Italy with acute, apparently type B hepatitis (hepatitis B surface antigen (HBsAg) positive). In 320 patients (85%) a positive IgM anti-HBc test result confirmed that hepatitis was due to primary infection with hepatitis B virus. In the remaining 56 patients absence of the IgM marker indicated that they were previously unrecognised long term carriers of HBsAg. Further serum analysis often showed delta infection and occasionally hepatitis A or cytomegalovirus infection as the true cause of their illness. After six to eight months circulating HBsAg persisted in 38 of 45 patients (84%) without IgM anti-HBc but in only six of 150 patients (4%) with the IgM antibody (p less than 0.0001). A negative IgM anti-HBc test result in patients with acute HBsAg positive hepatitis points to a factor other than hepatitis B virus as the cause of the liver damage and predicts the carriage of HBsAg.     

Patterns of natural killer cell function activation in response to interferon in chronic HBsAG positive hepatitis: relationship with the state of viral infection and with the early clinical response

In an effort to define immunobiological parameters identifying "responders" vs "non-responders" to IFN among hepatitis patients, 16 patients with chronic active hepatitis were screened for changes of Natural Killer cell activity (NK). 10/16 patients replicated the hepatitis B virus (HBV-DNA positive) whereas 6/16 replicated the defective B virus associated delta virus (HDV-RNA positive). Patients received 9 MU/3x/weekly/3 months of recombinant IFN alpha A. Mean NK activity of the HBV-DNA patients rose significantly from 29.9 +/- 5.3 to 45 +/- 4.7 during therapy, whereas the 6/16 HDV-RNA positive patients did not show any significant increase of NK activity. Interestingly, individual HDV-RNA positive patients exhibiting boosted NK activity also showed improvement of disease confirmed by clearance of intrahepatic delta antigen at one year. No such a correlation was found amongst the HBV-DNA positive patients. These data indicate that in spite of widespread individual variability, IFN-mediated NK boost may herald delta clearance and help in identifying "responders" and "non-responders" in IFN trials.     

Prevalence of GB virus C/hepatitis G virus in Hungary

In 1995 a new flavivirus, GB virus C/hepatitis G virus (GBV-C/HGV), was discovered. The aim of this study was to determine the prevalence of the virus in healthy persons and hepatitis patients in Hungary. The sera of 408 healthy persons older than 60 years were tested for the presence of GBV-C/HGV antibodies, and 113 were positive (28%). Eight of the 71 healthy persons younger than 60 years and twenty of the 51 sera (39%) taken from patients suffering from hepatitis of unknown origin proved to be positive for GBV-C/HGV antibodies. Ten of the 124 sera (8%) of healthy persons and 36 of the 247 sera (14.6%) of hepatitis patients proved to be positive for GBV-C/HGV RNA. Eleven PCR products were sequenced, and the sequences were found to be different from each other and from the previously published ones. However, three sequences taken from the same patient at different times were identical. These results show that GBV-C/HGV is present in Hungary and cannot be considered rare.     

Evaluation of an enzyme immunoassay for hepatitis C virus antibody detection using a recombinant protein derived from the core region of hepatitis C virus genome

This study was undertaken to evaluate an enzyme immunoassay (EIA) for hepatitis C virus antibody detection (anti-HCV), using just one antigen. Anti-HCV EIA was designed to detect anti-HCV IgG using on the solid-phase a recombinant C22 antigen localized at the N-terminal end of the core region of HCV genome, produced by BioMérieux. The serum samples diluted in phosphate buffer saline were added to wells coated with the C22, and incubated. After washings, the wells were loaded with conjugated anti-IgG, and read in a microtiter plate reader (492 nm). Serum samples of 145 patients were divided in two groups: a control group of 39 patients with non-C hepatitis (10 acute hepatitis A, 10 acute hepatitis B, 9 chronic hepatitis B, and 10 autoimmune hepatitis) and a study group consisting of 106 patients with chronic HCV hepatitis. In the study group all patients had anti-HCV detected by a commercially available EIA (Abbott), specific for HCV structural and nonstructural polypeptides, alanine aminotransferase elevation or positive serum HCV-RNA detected by nested-PCR. They also had a liver biopsy compatible with chronic hepatitis. The test was positive in 101 of the 106 (95%) sera from patients in the study group and negative in 38 of the 39 (97%) sera from those in the control group, showing an accuracy of 96%. According to these results, our EIA could be used to detect anti-HCV in the serum of patients infected with hepatitis C virus.     

Identification, using sera from exposed animals, of putative viral antigens in livers of primates with callitrichid hepatitis.

Callitrichid hepatitis (CH) is an acute, frequently fatal viral hepatitis which affects members of the primate family Callitrichidae (R. J. Montali, E. C. Ramsay, C. B. Stephensen, M. Worley, J. A. Davis, and K. V. Holmes, J. Infect. Dis. 160:759-765, 1989; E. C. Ramsay, R. J. Montali, M. Worley, C. B. Stephensen, and K. V. Holmes, J. Zoo Wildlife Med. 20:178-183, 1989). Outbreaks of the disease occur in zoos and animal parks. In this study, CH-specific antigens were identified in the livers of infected animals by using immune sera from primates with CH and CH-exposed asymptomatic animals. Three CH-specific antigens with apparent molecular masses of 34, 54, and 65 kDa were identified. A polyclonal antiserum was raised against the 54-kDa antigen. These antigens were not found in the livers of uninfected animals and may be viral proteins. Our results suggest that at least five of the six outbreaks of CH considered here were caused by the same virus or by an antigenically related virus.     

Comparison of the radioimmunological and immunoenzymatic methods in detection of HBsAg]

We have compared the solid-phase radioimmunoassay(SPRIA) with a solid-phase enzyme-immunoassay (EIA) in the detection of hepatitis B surface antigen (HBsAg). 708 sera from blood donors and 500 sera from patients with various diseases (acute and chronic hepatitis, chronic renal failure in hemodialytic treatment) were tested for HBsAg with both methods. 208 sera (17,2%) were found to be positive in SPRIA and 209 sera (17,3%) in EIA. Two HBsAg positive sera were tested in dilution series with both methods, too. The results show that the sensitivity and specificity of the EIA compare very favourably with those of the SPRIA.     

Evaluation of enzyme-linked immunosorbent assay using crude Leishmania and recombinant antigens as a diagnostic marker for canine visceral leishmaniasis

The performances of ELISA assays with different antigen preparations, such as Leishmania amazonensis or L. chagasi lysates and the recombinant antigens rK-39 and rK-26, were compared using sera or eluates from dried blood collected on filter paper to detect anti-Leishmania antibodies in dogs from a visceral leishmaniasis-endemic area in Brazil. Of 115 IFAT-reactive dogs at 1:40 titre, 106 (92.2%) were positive in parasitological exams (skin and/or spleen). These animals were compared to healthy animals (n = 25), negative for IFAT at a titre of 1:40 and parasitological exams. The sensitivities of crude and recombinant antigens were similar and remarkably high for both sera and eluates (97-100%). Specificity was higher than 96% for sera and eluates for different antigens, except for L. chagasi antigen using eluates (88%). Concordance values among the tests were higher either for sera or eluates (J = 0.95-1.00). High concordances were observed between sera and eluates tested with different antigens (kappa = 0.93-0.97). Crude and recombinant antigens identified different clinical phases of canine leishmaniasis. These results show that eluates could be used in canine surveys to identify L. chagasi infection. Recombinant antigens added little when compared to crude antigen in identifying positive dogs. Cross-reactivity with other diseases whose distribution often overlaps VL-endemic areas is a limitation of crude antigen use however.     

Identification of multiple Epstein-Barr virus-induced nuclear antigens with sera from patients with rheumatoid arthritis.

By means of the protein immunoblot technique, the Epstein-Barr virus (EBV) nuclear antigen (EBNA) could be identified in a variety of EBV-transformed cell lines with anti-EBNA-positive sera from normal donors. The molecular weight of EBNA expressed in each of the cell lines varied between 70,000 and 75,000 and was dependent upon the strain of infecting virus. In contrast, 15 of 21 sera from patients with rheumatoid arthritis identified antigens in addition to EBNA. The most prominent of these antigens had molecular weights of 110,000 to 115,000 and 92,000. All of the EBV genome-positive cell lines except for QIMR-GOR and cell lines containing the P3HR-1 virus expressed these antigens. The antigens were not present in the EBV genome-negative Ramos and BJAB cell lines, nor were they identified with EBV seronegative sera, indicating that they were EBV related. There was no direct correlation between the presence of antibodies in sera to EBNA, viral capsid antigen or early antigen, and reaction with the 92,000-molecular-weight antigen in immunoblots, indicating that this antigen was distinct from previously described EBV-related antigens.     

应用血清学方法鉴别急性和慢性病毒性乙型肝炎

本文用ELISA间接法检测急性和慢性乙型肝炎病人血清特异性抗HBcIgG,用ELISA捕捉法检测特异性抗HBcIgM。11例急性乙肝病人急性期抗HBcIgM100％阳性,抗HBcIgG全部阴性;恢复期抗HBcIgM 81.8％阴转,抗HBcIgG则100％阳转。17例慢性乙肝病人抗HBcIgM82.35％阳性,抗HBcIgG 100％阳性。被检血清经密度梯度超速离心,证实抗HBcIgM和抗HBcIgG两类抗体反应在急性和慢性乙肝病人血清中具有不同的动态规律。     

Immunoglobulin G response against 10-kDa and 65-kDa heat-shock proteins in leprosy patients and their household contacts

Abstract We measured antibody responses to recombinant Mycobacterium leprae 65-kDa (rML65) and 10-kDa (rML10) by indirect ELISA in sera from leprosy patients, household contacts and healthy controls in a leprosy-endemic area in the north east of Argentina. Serum antibody levels to those antigens were correlated with IgM anti-phenolic glycolipid I (PGL-I) levels, with bacterial index and the period of time under chemotherapy. Bacterial index positive (BI⁺) patients showed higher mean values when compared with BI negatives (BI⁻). Among lepromatous patients a positive correlation was observed between IgG antibody responses to both recombinant antigens and IgM antibody response to PGL-I. Anti-rML10 test detected a higher percentage of positive/total than anti-rML65 in all leprosy groups and healthy contacts. Bacterial load, leprosy clinical form and the time under chemotherapy were factors which could influence levels of the antibody response. The contribution of these antibody studies for a precise and early diagnosis in leprosy is discussed.