Band heterotopia or double cortex in a male: bridging structures suggest abnormality of the radial glial guide system

A moderately retarded Japanese boy, with a normal male karyotype (46,XY), was diagnosed to have a subcortical band heterotopia or double cortex syndrome. The band heterotopia was relatively thick compared with that of other patients reported. On T2-weighted coronal MR sections, there were numerous radial linear structures between the cortex and the band, probably representing the trace of radial fibers. He had no family members with seizures or mental retardation. Over 50 described patients with this malformation have been female except two patients briefly mentioned by several investigators. Band heterotopia or the double cortex syndrome is inherited as a sex-linked dominant condition. Affected mothers may have affected daughters or sons with lissencephaly, suggesting a link between these disorders. This is the first detailed description of a male with band heterotopia.

[Detection of HIV-1 in plasma samples using microplate hybridization after RT-PCR]

We have developed a microplate hybridization(MH) technique, which utilizes the non-isotopic method of enzyme-linked assay for detection of HIV in the amplified product after PCR. HIV RNA extracted from plasma was amplified by RT-Nested-PCR using biotinylated-inner primers of gag, pol and env regions, respectively. The PCR product was visualized by 5% polyacrylamide gel electrophoresis and ethidium bromide staining. The heat-denatured PCR product was hybridized with HIVcDNA of each region which was immobilized to a microplate. The hybridized microplate was reacted with streptavidin-conjugate peroxidase and then the optical density(O.D.) was read at 490nm. The cut off value was determined at O.D. 0.25. The results of the electrophoresis of gag, pol and env regions were all positive in 53 HIV-1 seropositive samples from Japan and the USA, and all negative in 55 HIV-1 seronegative samples. Using the MH technique, USA samples showed a higher O.D. than the Japan samples, particularly in the pol region. The results of MH technique in gag and pol regions coincided with that of electrophoresis. But, one of 27 Japanese HIV-1 seropositive samples showed O.D. of less than 0.2 in only env region. This particular sample was classified by V3 peptide-based enzyme immunoassay as subtype E, which differs from the typical subtype B of Japan and USA samples. This suggests the presence of several genotypes in HIV-1 seropositive individuals in Japan. Based on this data, the MH technique using gag, pol and env region is a simple, sensitive, safe and specific assay for detection of HIV-1 RNA in plasma, and would be useful in clinical testing.

[ELISA for diagnosis of infections by viruses]

The assay used most widely to detect or diagnose virus infection, especially infection of blood borne viruses e.g. HBV, HCV, HIV and HTLV, is the enzyme linked immunosorbent assay (ELISA), whose sensitivity and practicability have rendered it the most common primary screening assay. ELISA can be mass screening used automatic or semiautomatic machines. ELISAs can be indirect assay, competition assays or sandwich assays. In indirect and sandwich assays, the development of color indicates the presence of antigen or antibody, whereas in competition assays the absence of color development signifies a positive reaction. Alkaline phosphatase and horseradish peroxidase the most commonly used enzymes, are associated with their respective substrates, usually p-nitro-phenyl phosphate and hydrogen peroxide. The ELISA for antigen detection is used polyclonal antibody or monoclonal antibodies. The other hand, the ELISA for antibody screening is used whole virus, synthetic peptides or recombinant antigens.

[Clinical usefulness of urinary anti HIV antibody test--a large scale study from 11 institutes in Japan]

An enzyme immuno assay kit has been developed to detect anti-HIV antibody in urine. In order to examine the clinical utility of the kit, 1333 urine samples were assayed. These samples consisted of 233 urine samples from HIV infected patients, 472 samples from HIV uninfected patients including 203 samples from patients with urogenital diseases, and 628 samples from normal subjects. Anti-HIV antibodies were detected in all the urine samples from HIV infected patients, and the diagnostic sensitivity for HIV infection was 100% with no false negative cases. A variety of anti-HIV antibody titers were found in the urine samples from HIV infected patients. However, no significant differences were found in the distribution patterns of urinary anti-HIV antibody titers among AC, ARC and AIDS patients. False positives were determined in only five samples in 628 healthy subjects (0.8%), one in 19 patients with hepatitis (5.3%), one in 45 patients with hemophilia (2.2%) and two in 105 pregnant women (1.9%). The antibody titers of all the false positive samples in these groups were less than the cut-off index multiplied by two. However, relatively high positive rates were demonstrated in the samples from urogenital diseases (11.8%), diabetes mellitus (20.0%) and auto-immune diseases (7.3%). False positive results were found to be directly correlated to the protein concentration of urinary protein, especially the immunoglobulin concentration in urine. The assay system was also evaluated by various reproducibility tests performed by different operators at different laboratories. The test results were satisfactory.(ABSTRACT TRUNCATED AT 250 WORDS)

[Detection of HIV-1 proviral DNA in peripheral leukocytes by AMPLICOR HIV-1 test kit]

AMPLICOR HIV-1 test kits, which had been developed as an HIV-1 provirus detection test by PCR method, have been evaluated for its clinical diagnostic application. Sixty-six of HIV-1 antibody positive and 67 of HIV-1 antibody negative blood samples derived from hemophiliacs, who had received blood products, have been tested by AMPLICOR HIV-1. All of the results from AMPLICOR HIV-1 were consistent with those from antibody test and clinical aspects. Thirty-nine of HIV-1 antibody positive samples have been tested by AMPLICOR HIV-1 and virus isolation (culture method). Twelve of 39 (30.8%) were positive by virus isolation, and 39 of 39 (100%) were positive by AMPLICOR HIV-1. Two of new born infants from HIV-1 sero-positive mothers were tested by AMPLICOR HIV-1, and the result suggested that the kit would be useful for diagnosis of infants from sero-positive mothers. Based on these studies, AMPLICOR HIV-1 is considered as useful clinical diagnostic for HIV-1 proviral DNA detection.

Sequence analysis of V3 loop region of HIV-1 strains prevalent in India

The third variable (V3) domain of human immunodeficiency virus type 1 (HIV-1) env gene has been found to elicit type-specific neutralizing antibodies as well as a cytotoxic and helper T-cell response in both humans and animals. We analyzed the V3 domain of 8 HIV-1 isolates from India by using polymerase chain reactions. The V3 loops of 7 Indian isolates contained the apical tetra peptide GPGQ, while the V3 loop of one Indian isolate carried the apical tetra peptide GPGK. The amino acid sequences of the seven Indian isolates were closely related to each other, with an average of the nucleotide sequence homology of 96.0% (94.6 to 97.6%). The marked relatedness of the amino acid sequences among the seven Indian HIV-1 isolates indicated a recent and very rapid spread of this HIV-1 variant in Bombay. The amino acid sequence of the C2/V3 region of env gene of the 7 Indian isolates were homologous to the C subtype reported by Meyers et al. These findings could be useful in assessing the sources of infection and developing an AIDS vaccine.

Absence of nonpercutaneous transmission of hepatitis C virus in a colony of chimpanzees

Transmission of hepatitis C virus (HCV) was studied in a colony of 85 chimpanzees using assays for anti-HCV and HCV-RNA. Thirteen of the 85 sera were positive for anti-HCV, and 12 of the 13 were also positive for HCV-RNA. All of the anti-HCV positive sera except one were obtained from chimpanzees which had been inoculated with non-A, non-B hepatitis virus. On the other hand, only one of 63 sera of chimpanzees without history of experimental infection of the virus was positive for anti-HCV. Transmission to this chimpanzee was thought to be a needle contaminated with HCV. All 39 samples of chimpanzees born in the center were negative for both anti-HCV and HCV-RNA. Sixteen of their mothers had undergone experimental infection, and 6 of them were positive for both anti-HCV and HCV-RNA. These results suggest that nonpercutaneous transmission, including sexual and mother-to-infant transmissions, is not an important mode of transmission. If these findings apply to humans, definition of inapparent sources of the infection is needed.

[Risk of hepatitis C virus infection by needlestick among medical employees]

We have experienced 99 medical employees who had stuck themselves by the needles used by patients in the past 5 years. Sixteen of the 99 cases (16.2%) were of the patients who had hepatitis C Virus (HCV) antibodies. We followed up these 16 medical employees during 24.8 +/- 12.0 months. We could not find any case among them who had seroconverted HCV antibody positive in their serums. We concluded that the risk of HCV infection by the needlestick accident is not so high.

[HIV infection of CD4-CD8+ T-cell line derived from patients with HAM]

This studies have attempted human immunodeficiency virus (HIV) infection in four CD4+ or CD8+ T-cell lines derived from HTLV-I associated myelopathy virus (HAM) patients. Not only CD4+ cell line but also CD8+ cell line could be infected with HIV and CD4+ cell line showed a higher susceptibility than CD8+ cell line on HIV infection. HIV antigen in early stage after HIV inoculation was detected by using enzyme-linked immunosorbent assay (ELISA) rather than indirect immunofluorescence assay (IFA). HTLV-I producing CD4+ and CD8+ cell lines became to express two viral antigens (HTLV-I and HIV) after HIV inoculation. The results indicated that CD4-CD8+ T-cell line from patient with HAM can be infected with HIV. So that, we have found that other epitopes except for CD4 antigen may be associated with HIV infection.

Non-A, non-B hepatitis related AN6520 Ag is a normal cellular protein mainly expressed in liver. II

Detection of AN6520 Ag/Ab in human sera had indicated a close association with non-A, non-B hepatitis (NANBH). In this study, we investigated the immunochemical nature of AN6520 Ag and measured the amounts in various human and chimpanzee organs in order to clarify the association with NANBH. AN6520 Ag was found to be composed of polypeptide(s) with an apparent molecular weight of 45,000 daltons (45 kD), which are noncovalently linked together. Human antibodies in convalescent sera from NANBH patients as well as monoclonal antibodies were found to recognize only the high-order structure of the antigen, whereas rabbit antibody recognized both the high-order structure and the reduced form of 45 kD polypeptide(s). AN6520 Ag could be detected in most of the livers tested including those without any liver damage and fetal livers; their amounts varied considerably from each other. The antigen could be detected also in organs other than liver, but in contrast to liver, the amounts were small and did not vary as much between individuals. From the data of immunoblotting using rabbit antibody, our observed variation of antigen content in liver was considered to be due to the difference in expression of 45 kD polypeptide(s). Although no specific relationship was found between the amount of the antigen in liver and NANBH, the antigen was found to increase several times in livers of chimpanzees after the inoculation of NANBH virus. These data suggest that AN6520 Ag is a normal cellular protein existing mainly in liver and that its quantity may vary under some conditions such as NANBH.

Detection of an antigen (AN6520), possibly related to non-A, non-B hepatitis, by monoclonal antibodies. I

The antibody to AN6520 antigen, which was isolated from the liver of a patient with non-A, non-B hepatitis (NANBH), has been detected frequently in convalescent sera from patients with NANBH by the passive hemagglutination (PHA) test. In a further study, we established hybridoma cells secreting antibodies against AN6520 antigen and obtained ascitic fluids with PHA titers ranging from 1:10(5) to 1:10(7). In immunodiffusion with AN6520 antigen, all monoclonal antibodies were found to form an identical precipitin line. These lines were also identical to those formed by rabbit antiserum against AN6520 antigen and by convalescent sera from patients with NANBH. With one of the monoclonal antibodies, 1-F12, solid-phase radioimmunoassay (SP-RIA) for detecting AN6520 antigen was developed as well as blocking RIA for anti-AN6520 antibody detection. The antigen assay was 50 times more sensitive than the reverse passive hemagglutination (R-PHA) test, with a sensitivity threshold of the 1 ng/ml of antigen solution; the antibody assay was 10 times more sensitive than PHA. The results with this blocking RIA were mostly in agreement with the data obtained by PHA. Furthermore, the antigen in human sera, which had never been detected by R-PHA test, could be detected by SP-RIA.

A case-control study on liver cancer with special emphasis on the possible aetiological role of schistosomiasis

In order to elucidate the relationship between liver cancer and suspected aetiological factors, a case-control study was carried out at seven hospitals in Yamanashi prefecture, where the mortality rate of the disease was significantly higher than the corresponding national figure. This prefecture was also recognised as one of the endemic areas for Schistosoma japonicum in Japan. Sixty-two cases of liver cancer, and the same number of controls were selected during the two-year study period. A skin test for Schistosoma japonicum, serum tests for HB virus and a questionnaire study were carried out. The results of matched pair analysis revealed that liver cancer was significantly highly correlated with three factors, that is, HBs antigen (HBsAg), history of schistosomiasis, and daily intake of alcohol, and that their odds ratios were 10.0, 9.5 and 3.2 respectively. The values of percentage population attributable risk for these three factors were estimated to be 21.3%, 71.8% and 39.8% respectively. The above findings suggest that HBsAg and history of schistosomiasis are both important risk factors for liver cancer and that schistosomiasis may be much more important than HB virus in the area. The analysis of combinations of these three factors suggest that each factor might be related to liver cancer multiplicatively rather than additively.

Use of monoclonal antibodies in the assay of hepatitis B core antigen and antibody

Hybridoma cells secreting antibody against hepatitis B core antigen (HBc Ag) were prepared. BALB/c mice were immunized with 0.2 ml of purified HBc Ag, and their spleen cells were fused with mouse myeloma (P3U1) cells by means of polyethylene glycol 1000. Activities of antibodies against HBc Ag (anti-HBc) were tested by the immune adherence hemagglutination (IAHA) and reverse passive hemagglutination inhibition (RPHI) techniques. Hybridoma cells found to contain antibodies accounted for 26.5% by IAHA and 52.1% by RPHI, respectively. Among 32 monoclonal anti-HBc antibodies, 18 were found to be positive by both IAHA and RPHI, and the remaining 14 positive by RPHI only. After cloning, they were injected intraperitoneally into ascitic mice. The highest anti-HBc activity with an IAHA titer of 1:4 X 10(6) and with an RPHI titer of 1:1 X 10(5) was detected in this ascitic fluid. Enzyme immunoassay (EIA) and RPHI with monoclonal antibody containing the highest anti-HBc activity were developed. All the sera in which anti-HBc was detected by IAHA and RPHI with polyclonal antibody were positive in EIA. RPHI titers obtained with monoclonal antibody were in good agreement with usual IAHA and RPHI titers obtained with polyclonal antibody. These results indicate that monoclonal antibody can be used in the HBc Ag and anti-HBc assay system.

Susceptibility of hepatitis B virus to disinfectants or heat

Using direct chimpanzee inoculation as an assay method, we tested the abilities of the following chemical or physical treatments to inactivate hepatitis B virus in human plasma: 1% aqueous glutaraldehyde at 24 degrees C for 5 min, 0.1% aqueous glutaraldehyde at 24 degrees C for 5 min, 80% ethyl alcohol at 11 degrees C for 2 min, and heat at 98 degrees C for 2 min. All treatments were shown to be effective, indicating that the resistance level of the hepatitis B virus is not extreme.

Efficacy of hepatitis B vaccine in chimpanzees given transfusions of highly infective blood

The protective efficacy of a hepatitis B vaccine against infections from transfusions of large volumes of highly infective blood in five immunized chimpanzees was assessed. Hepatitis B surface antigen (HBsAg) became positive and antibody to HBsAg (anti-HBs) disappeared soon after transfusion in the five chimpanzees. Two chimpanzees that had HBsAg only on the day of transfusion did not develop infection. However, the remaining three chimpanzees with persistent HBsAg antigenemia for three to four days developed serologic evidence of infection. Two chimpanzees did not have hepatitis and the third had a mild, transient case of acute hepatitis. The hepatitis B vaccine prevented the four immunized chimpanzees from developing illness. The remaining chimpanzee developed hepatitis, but a rapid booster response of anti-HBs owing to the previous vaccination appeared to lighten the severity of the disease and prevent chronicity.

Production of hepatitis B e antibody in Epstein-Barr virus-induced B lymphocyte cell lines

B lymphocytes separated from anti-HBe-positive donors were established as lymphoblastoid cell lines by infection with EBV, but anti-HBe in the culture supernatant from such lymphoblastoid cell lines could not be detected. The lymphoblastoid cell lines were rosetted with HBe antigen-coupled SRBC to prepare cells for the production of specific anti-HBe. Antibody activity in the culture supernatant against rosette forming cells was detected by RIA, ID, and R-PHI tests during the first 1 to 4 wk, but not after 5 wk. The activity in the supernatant was not destroyed by treatment with 2-mercaptoethanol, indicating that the antibody might be IgG.