Antibodies to human immunodeficiency virus in human sera induce cell-mediated lysis of human immunodeficiency virus-infected cells

The capacity of human immunodeficiency virus (HIV) antibody-positive sera from homosexually active men without acquired immune deficiency syndrome to lyse the HIV-infected T cell lines MOLT-4f and CCRF-CEM (CEM) in cooperation with lymphocytes from normal donors was investigated. Twenty-seven HIV antibody-positive sera, most of which enhanced the killing of HIV-infected MOLT-4f and CEM target cells by normal mononuclear cells were studied in detail. HIV antibody-positive sera resulted in lysis at dilutions as high as 1/10,000. HIV antibody-negative sera did not augment lysis of infected target cells. In addition, lysis of uninfected targets was not enhanced in the presence of HIV antibody-positive sera. Because fractionation of the HIV antibody-positive sera on a protein A affinity column resulted in recovery of the activity from the IgG fraction, the extra cytotoxic activity mediated by nonimmune cells in the presence of immune sera appears to be antibody-dependent. Furthermore, the cytotoxic effector cells were in the nonrosetting fraction of lymphocytes and expressed Leu-11 (cluster designation (CD)15) antigens, which is characteristic of cells participating in antibody-dependent cellular cytotoxicity reactions. The antibody specificity of the sera, determined by radioimmunoprecipitation, provides evidence that antibody-dependent cellular cytotoxicity can occur even when there are no detectable antibodies directed against gag proteins. Sera which lacked detectable antibodies to the envelope protein gp120 by radioimmunoprecipitation did not mediate antibody-dependent cellular cytotoxicity.     

Comparison of indirect immunofluorescence (IF) test with enzyme-linked immunosorbent assay (ELISA) in screening of hybridomas to very virulent Marek's disease virus.

For identifying virus-specific antigens of Marek's disease virus (MDV), monoclonal antibodies (MAbs) against strain Md5 of serotype 1, which is known to be a very virulent MDV (vvMDV), were isolated. Fifty-eight hybridoma clones that secreted MAbs against vvMDV were obtained. Of these MAbs, 36 gave positive reactions in an immunofluorescence (IF) test, and 22 gave positive reactions on enzyme-linked immunosorbent assay (ELISA). None of these MAbs gave positive reactions in both the IF test and ELISA. Of the MAbs that gave positive reactions in the IF test, 33 clones reacted with MDV1-specific epitopes, the other three reacting with MDV1-HVT intertypic epitopes. None of the clones reacted with MDV1-MDV2 intertypic epitopes. Three virus-specific polypeptides were identified by radioimmunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) or immunoblotting. These polypeptides were recognized by 12 MAbs giving positive reactions by IF, but by none of those giving positive reactions by ELISA. In addition, size heterogeneity of the MDV1-specific phosphorylated polypeptides in the MDV1 strains was shown using the MAbs against Md5.     

Isolation of a reticuloendotheliosis virus from chickens inoculated with Marek's disease vaccine.

Over a period from spring to fall in 1974, a disease with delayed growth, anemia, abnormal feathers, and leg paralysis as main symptoms broke out in flocks of chickens inoculated with Marek's disease vaccine. A virus was isolated from affected birds in the field and the same lot of Marek's disease vaccine as inoculated into these birds. It had a common antigenicity to the T strain of reticuloendotheliosis virus (REV) and could not be discriminated from this strain on the basis of morphology or property. When chicks were inoculated with it, they presented essentially the same symptoms as the birds affected in the field. Since the disease was reproduced in this manner, it was presumed to have been caused by REV contained in the vaccine as contaminant. The virus persisted in the body for long time and also induced horizontal infection.     

Persistence of genomes of both herpesvirus of turkeys and Marek's disease virus in a chicken T-lymphoblastoid cell line

A cell line tentatively designated as MDCC-BO1(T), was established from spleen cells of an apparently healthy chicken inoculated with herpesvirus of turkey (HVT). BO1(T) cells were T lymphoblastoid cells and the more than 95% of them had Marek's disease (MD) tumor-associated surface antigen (MATSA). However, no viral internal antigens or membrane antigens could be demonstrated in them by immunofluorescence tests using chicken anti-HVT and -MD virus (MDV) sera. The virus could be rescued from BO1(T) cells by co-cultivation with chick embryo fibroblasts (CEF). The DNA of the rescued virus was characterized as HVT DNA by its sedimentation profile in a neutral glycerol gradient and its endonuclease Hind III cleavage-pattern. Ultrastructural studies on CEF infected with the rescued virus revealed the presence of HVT-like virions. However, DNA-DNA reassociation kinetics showed that the BO1(T) cells contained a few copies of NVT and also MDV genomes.     

Changes in the Gallus gallus proteome induced by Marek's disease virus

Marek's disease virus (MDV) is a highly oncogenic avian herpesvirus. We have used a modified MudPIT analysis to examine the effect of MDV infection on the chicken proteome. We identified 3561 unique nonphosphorylated peptides, representing 1460 chicken proteins, in a mock-infected sample versus 4240 unique nonphosphorylated peptides, representing 1676 proteins, in an MDV-infected sample. Of these unique peptides, 59.1% from the mock- and 49.6% from the MDV-infected samples were detected in both samples, and for the represented proteins, 69.1% from the mock- and 60.2% from the MDV-infected samples were common to both samples. In terms of phosphorylation, 357 and 506 phosphopeptides, representing 342 and 483 proteins, were detected in the mock- and MDV-infected samples, respectively. At the phosphopeptide level, 10.1% from the mock- and 7.1% from the MDV-infected samples overlapped, and for the represented phosphoproteins, 12.0% from the mock- and 8.5% from the MDV-infected samples were common to both samples. There were no significant differences in the hydropathicity values and number of transmembrane domains of the identified protein sets. Subtle differences were observed for subcellular localizations of the identified proteins. These results suggest that MDV infection may alter host cell biochemistry by perturbing the host's proteomic composition.     

Cytogenetic stability of chicken T-cell line transformed with Marek's disease virus: atomic force microscope, a new tool for investigation

The Marek's disease virus (MDV) integration may induce a novel organization of chromatin architecture with a modified genetic expression. In our opinion it is worthwhile trying to relate cytogenetic stability to functional modifications. Recently, atomic force microscopy technique was applied to study the structure of chromosomes at a nanoscale level. This high resolution allows to investigate the different structure of chromatin in order to study cytogenetic stability and chromosome aberrations due to MDV insertion. In this paper data are presented indicating a duplication [78,WZ,dup(1p)(p22-p23)] and a deletion [78,WZ cht del(3)(q2.10)] of Chromosomes 1 and 3 relatively. Relationships between GTG (G-bands by Trypsin using Giemsa) bands and the topography of chromosomes are also discussed, naming them Topographic Banding. The architecture of chromosomes observed by AFM can be related to the data obtained with classic banding techniques thus overcoming the optical resolution limits. The presence of chromatin bridges between sister chromatids at most of the heterochromatic regions is also evidenced. Besides, we present different studies of the longitudinal and transversal symmetry of the hetero and euchromatic regions to clearly demonstrate a different underlying architecture of these regions. It is indeed evident that the heterochromatic bands are more symmetrical than euchromatic bands.     

Antibodies to hepatocyte membrane antigens in chronic liver disease: detection by immunofluorescence after Bouin's fixation

Using a modified indirect immunofluorescent (IF) technique in which cryostat tissue sections were fixed in Bouin's solution for ten minutes prior to reaction with sera under test, we have looked for antibodies to the hepatocyte membrane (HMA) in the sera of patients with chronic active hepatitis (CAH) and primary biliary cirrhosis (PBC). Samples were tested initially in parallel on unfixed and Bouin's-fixed rat composite blocks (kidney, stomach, liver) at a titer of 1:100 and those found to be positive were diluted further and reexamined. Conventional unfixed sections of rat composite block showed no liver membrane immunofluorescence although antinuclear (ANA), mitochondrial (AMA), and smooth muscle antibodies (SMA) were detected as anticipated. By contrast, prior Bouin's fixation abolished most of the fluorescence due to ANA, AMA and SMA but resulted in brilliant fluorescence of rat hepatocyte membranes in eleven of twelve patients with CAH (93%) and all ten patients with PBC. Only one of 22 normals (5%), one of 20 with collagen-vascular diseases (5%), and one of seven with nonimmunologic liver disease (14%) were positive for this hepatocyte membrane antibody. Bouin's fixation prior to IF is a simple technique which appears to alter the hepatocyte membrane so that HMA become detectable. The strong association of HMA with CAH and PBC suggests that this test might be of value and may contribute towards a further understanding of the pathogenesis of these conditions.     

Complete genome sequence analysis of a recent chicken anemia virus isolate and comparison with a chicken anemia virus isolate from human fecal samples in china

A new isolate of chicken anemia virus (CAV) was designated GD-1-12. GD-1-12 was isolated from a 12-day-old commercial broiler in Guangdong province, China, in 2012. The GD-1-12 CAV caused high mortality, severe anemia, thymic atrophy, and subcutaneous hemorrhage in commercial broilers. Here, we report the complete genome sequence of GD-1-12 CAV and comparison with the complete genome sequence of another CAV that was isolated from human fecal samples in China (GenBank accession no. JQ690762). The genomes of the two CAV isolates shared high homology, although a deletion was identified by comparison. The findings from this study provide additional insights into the molecular characteristics of the CAV genomes and should advance knowledge for continuous monitoring and, perhaps, preventing the spread of the virus in chickens as well as in humans.