Detection of viral antigens in patients with IgA nephropathy.

Immunofluorescent analysis of viral antigens in the cultured fibroblasts and renal tissues in patients with IgA nephropathy was described. Freeze and thawed extracts of pharyngeal cells obtained from patients with IgA nephropathy, chronic proliferative glomerulonephritis without IgA deposition (PGN) and healthy adults were cultured with human fibroblasts, i.e. Hel cells, with or without addition of 5-iodine 2'-deoxy-uridine (IUDR) at 37 degrees C for 2 weeks. These fibroblasts and renal sections were stained with several kinds of FITC-labeled antiviral antibodies. Deposition of adeno, herpes simplex, varicella zoster or parainfluenza 3 was observed not only in the renal sections but also in the nuclear regions and/or cytoplasm of Hel cells after incubation of extracts of pharyngeal cells with or without IUDR from patients with IgA nephropathy. It is indicated that antigenic stimulation in the upper respiratory tracts may be due to several different types of DNA and/or RNA viruses in patients with IgA nephropathy. It appears that these antigenic substances show some heterogeneity among these patients.

Identification and characterization of a varicella-zoster virus DNA-binding protein by using antisera directed against a predicted synthetic oligopeptide.

We have identified, in varicella-zoster virus (VZV)-infected cells, the product of the gene predicted to code for the VZV analog of the herpes simplex virus major DNA-binding protein. The open reading frame of the VZV gene has the potential to code for a protein with a predicted molecular weight of 132,000 (a 132K protein). To detect the protein, a 12-amino-acid oligopeptide corresponding to the carboxyl terminus of the putative open reading frame was synthesized and used to prepare antisera in rabbits. The resulting antibodies reacted specifically in Western immunoblot analysis and immunoprecipitation with a single 130K polypeptide found in VZV-infected cells. The specific reactivity of the antisera with the 130K polypeptide was inhibited by the addition of synthetic peptide. Immunofluorescence studies with the antisera as probe for the 130K polypeptide suggested that this peptide is located predominantly within the nuclei of infected cells. Analysis of proteins that bind to single-stranded DNA immobilized on cellulose matrices indicated that 30 to 50% of the 130K polypeptide is capable of interacting with single-stranded DNA and that this interaction is overcome with 0.5 M NaCl. Thus, we have prepared a specific polyclonal antiserum that identifies a VZV DNA-binding protein whose properties are similar to those of the herpes simplex virus ICP8 (Vmw130) DNA-binding protein.

Molecular epidemiology of live, attenuated varicella virus vaccine in children with leukemia and in normal adults.

Restriction endonuclease analysis of varicella-zoster virus (VZV) DNA has been used in unraveling the complex epidemiology of VZV infections in individuals immunized with a live, attenuated varicella virus vaccine. Early rashes appearing within the first six weeks after vaccination are invariably due to vaccine virus. True breakthrough infections with wild-type VZV also occur in vaccinees. Five cases of zoster have been seen in leukemic children vaccinated while in remission. One case appeared 22 months after vaccination in the same general area as the inoculation. The virus isolated was vaccine derived. A second case of zoster appeared in a dermatome unrelated to the sites of vaccination approximately 19 months after apparently natural varicella. This virus was wild type. Vaccine virus can therefore establish latency and can later reactivate as herpes zoster.

Identification of an Epstein-Barr virus glycoprotein which is antigenically homologous to the varicella-zoster virus glycoprotein II and the herpes simplex virus glycoprotein B.

The Epstein-Barr virus (EBV) antigenic homologue of the varicella-zoster virus glycoprotein II and the herpes simplex virus (HSV) glycoprotein B (gB) was identified through cross-reactivity with anti-glycoprotein II and anti-glycoprotein B peptide sera. The homologue is the previously characterized EBV glycoprotein, with an apparent molecular weight of 125,000 Da, which is synthesized late during productive EBV infection and appears to be encoded by the BamHI A EBV fragment. This glycoprotein, but not other EBV proteins, reacted with the antisera in immunoprecipitation experiments and by ELISA. In addition, absorption of the sera with the purified EBV 125-kDa glycoprotein removed the cross-reacting antibody. Whether the EBV gB homologue has the same biological functions associated with HSV gB has yet to be determined.

Subarachnoid hemorrhage and granulomatous angiitis of the basilar artery: demonstration of the varicella-zoster-virus in the basilar artery lesions.

A 70-year-old man, with regional herpes zoster (C2) of 10 weeks duration, died following subarachnoid hemorrhage caused by the rupture of an aneurysm in the basilar artery. Granulomatous angiitis, with multinucleated giant cells, was found at autopsy in the wall of the aneurysm. Electron microscopy of the basilar artery disclosed intracytoplasmic viral particles with an envelope which measured 150-220 nm in diameter. Immunohistochemistry studies revealed varicella-zoster-virus-related antigen in the cytoplasm and/or in the nucleus of histiocytes in the vessel wall. These findings suggest that varicella-zoster virus may be linked to the development of granulomatous angiitis.

Neutralization epitope of varicella zoster virus on native viral glycoprotein gp118 (VZV glycoprotein gpIII).

Varicella-zoster virus (VZV) specifies the formation of several glycoproteins, including a 118,000-Da mature structural product (gp118). The biologic and biochemical properties of gp118 were studied after production of murine monoclonal antibodies to both a lowpassage laboratory strain (VZV-32) and an attenuated vaccine strain (VZV-Oka). Structural analyses performed with the three glycosidases endo-beta-N-acetylglucosaminidase H (endoglycosidase H), endo-beta-N-acetylglucosaminidase F (endoglycosidase F), and endo-alpha-N-acetylgalactosaminidase demonstrated that gp118 was predominantly an N-linked complex type glycoprotein built upon a polypeptide backbone of approximately 79,000 Da. Sialic acid residues were present on the mature glycoprotein, but these terminal sugars were absent from the partially glycosylated intermediate forms recovered from monensin-treated infected cultures. Unlike another VZV-specified glycoprotein gp98, no new oligosaccharide moieties were observed on gp118 after addition of tunicamycin to VZV-infected cultures. By plaque reduction assays with a panel of monoclonal antibodies, we defined an epitope on this glycoprotein which elicited a complement-independent neutralizing antibody response of high magnitude. The epitope was highly conserved, since it was present on a laboratory VZV strain, wild type isolates, as well as the attenuated vaccine strain (VZV-Oka). Competitive blocking experiments with the same anti-gp118 monoclonal antibodies indicated that four neutralizing antibodies were directed against similar or identical epitopes whereas one nonneutralizing antibody reacted with a different antigenic site. Thus, this study demonstrates the presence of an immunodominant neutralization epitope on native viral glycoprotein gp118. Under a new consensus nomenclature, this glycoprotein will be designated VZV gpIII.

Varicella-zoster viral glycoprotein envelopment: ultrastructural cytochemical localization.

The periodate-thiocarbohydrazide silver proteinate (PA-TCH-SP) method was used to study the envelopment process in varicella-zoster virus-infected human melanoma cells. Viral envelopment could be seen at two sites, the nuclear membrane and at virus-induced intracytoplasmic vacuoles. Virus-associated glycoconjugates were detected by the PA-TCH-SP method at the plasmalemma and on the inner membrane of the intracytoplasmic vacuoles. Virion envelopes acquired at the nuclear membrane were PA-TCH-SP negative, whereas those acquired at intracytoplasmic vacuoles were PA-TCH-SP positive. All virions found inside these vacuoles contained periodate-reactive envelopes. Release of virions into the extracellular space, where virtually all virions were PA-TCH-SP positive, appeared to be via exocytosis. Thus, the PA-TCH-SP method identifies glycoprotein incorporation at specific cytoplasmic vacuoles distinct from nuclear envelope, endoplasmic reticulum, and Golgi lamellae. These results suggest that envelopment within the cytoplasm is a stage in the assembly of the varicella-zoster virion.

Varicella-zoster virus p32/p36 complex is present in both the viral capsid and the nuclear matrix of the infected cell.

Varicella-zoster virus (VZV) directs the synthesis of numerous glycosylated and nonglycosylated infected-cell-specific proteins, many of which are later incorporated into the virion as structural components. In this study, we characterized a nonglycosylated polypeptide complex with the aid of a VZV-specific murine monoclonal antibody clone, 251D9. As detected by indirect immunofluorescence, the antibody bound mainly to antigens located within the nuclei of infected cells and did not attach to an uninfected cell substrate. The polypeptide specificity of the monoclonal antibody was determined by immunoblot analysis of electrophoretically separated infected cell extracts to react with a 32,000-molecular-weight VZV-specific protein (p32); in addition, the antibody also bound to a 36,000-molecular-weight polypeptide. The synthesis of these antigens was unaffected by inhibitors of glycosylation. Nonionic or ionic detergents were only marginally effective in solubilization of the p32-p36 complex, and relatively small amounts were eluted from nuclei by high salt concentrations (2 M NaCl). The same proteins remained associated with the nuclear matrix of VZV-infected cells. We also demonstrated that the protein complex was a major component of purified VZV nucleocapsids; p32 was especially prominent in both full and empty capsids. Immunoblot analysis of the nucleocapsid preparation revealed two additional species (p34 and p38) in the p32-p36 complex. Phosphorylation was a distinctive feature of some of the constituents. In summary, these results indicate that the p32-p36 complex represents a family of structural proteins closely associated with the assembly of VZV nucleocapsids and the encapsidation of viral DNA.

Identification of the products of a varicella-zoster virus glycoprotein gene.

Two of the genes identified from the previously published DNA sequence of the Us component of the varicella-zoster virus (VZV) genome were predicted to encode membrane proteins with polypeptide molecular weights of 39000 (39K) and 70K. A rabbit antiserum directed against a unique peptide containing the seven amino acid residues at the carboxy terminus of the 39K gene product specifically precipitated glycoproteins with apparent molecular weights of 55K and 45K from VZV-infected cells labelled with [3H]mannose. The complete inhibition of precipitation of gp55 by free peptide and the partial inhibition of precipitation of gp45 support the conclusion that the 39K gene encodes gp55 and perhaps gp45. The number of VZV genes currently thought to encode glycoproteins is discussed in view of this finding.

Varicella-zoster virus envelope glycoproteins: biochemical characterization and identification in clinical material.

Varicella-zoster virus (VZV)-infected human foreskin fibroblasts synthesize viral glycoproteins of 125,000 (gp125), 118,000 (gp118), 92,000 (gp92), 63,000 (gp63), 59,000 (gp59), and 47,000 (gp47) Da. In biochemical studies, all of these VZV glycoproteins were shown to contain asparagine-linked (N-linked) oligosaccharide chains and, except for gp125 and gp47, to be sialoglycoproteins. Experiments with endo-beta-N-acetylglucosaminidase H (endo H) demonstrated that gp92 contained only complex type (endo H-resistant) N-linked glycosyl chains, while the other mature glycoproteins contained both high-mannose (endo H-sensitive) and complex-type oligosaccharides. Monoclonal antibodies recognizing multiple glycoproteins, gp63/gp125 or gp92/gp59/gp47, neutralized virus infection, suggesting the glycoproteins were important components of the virus envelope. This was confirmed for gp92/gp59/gp47 by immunoelectron microscopy, which revealed dense staining localized exclusively to the virion envelope and to the plasma membrane of virus-producer cells. The mature forms of all of these glycoproteins were also present in viral material isolated from vesicles of varicella and zoster patients, indicating that in infected individuals the viral glycoproteins are synthesized and processed in a manner similar to that in tissue culture cells.

Structural analysis of the varicella-zoster virus gp98-gp62 complex: posttranslational addition of N-linked and O-linked oligosaccharide moieties.

Varicella-zoster virus specifies the formation of several glycoproteins, including the preponderant gp98-gp62 glycoprotein complex in the outer membranes of virus-infected cells. These viral glycoproteins are recognized and precipitated by a previously described monoclonal antibody designated monoclone 3B3. When an immunoblot analysis was performed, only gp98 was reactive with monoclone 3B3 antibody; likewise, titration in the presence of increased concentrations of sodium dodecyl sulfate during antigen-antibody incubations caused selective precipitation of gp98 but not gp62. Further structural analyses of gp98 were performed by using the glycosidases endo-beta-N-acetylglucosaminidase H (endoglycosidase H) and neuraminidase and two inhibitors of glycosylation (tunicamycin and monensin). In addition to gp98, antibody 3B3 reacted with several intermediate products, including gp90, gp88, gp81, and a nonglycosylated polypeptide, p73. Since gp98 was completely resistant to digestion with endoglycosidase H, it contained only complex carbohydrate moieties; conversely, gp81 contained mainly high-mannose residues. Polypeptide p73 was immunodetected in the presence of tunicamycin and designated as a nascent recipient of N-linked sugars, whereas gp88 was considered to contain O-linked oligosaccharides because its synthesis was not affected by tunicamycin. The ionophore monensin inhibited production of mature gp98, but other intermediate forms, including gp90, were detected. Since the latter product was similar in molecular weight to the desialated form of gp98, one effect of monensin treatment of varicella-zoster virus-infected cells was to block the addition of N-acetylneuraminic acid. Monensin also blocked insertion of gp98 into the plasma membrane and, as determined by electron microscopy, inhibited envelopment of the nucleocapsid and its transport within the cytoplasm. On the basis of this study, we reached the following conclusions: the primary antibody 3B3-binding epitope is located on gp98, gp98 is a mature product of viral glycoprotein processing, gp98 contains both N-linked and O-linked oligosaccharide side chains, gp90 is the desialated penultimate form of gp98, gp88 is an O-linked intermediate of gp98, gp81 is the high-mannose intermediate of gp98, and p73 is the unglycosylated precursor of gp98.

Analysis of three late varicella-zoster virus proteins, a 125,000-molecular-weight protein and gp1 and gp3.

Two monoclonal antibodies were prepared against varicella-zoster virus proteins. One of the monoclonal antibodies (10.2) reacted only with the nuclei of infected cells and immunoprecipitated one nonglycosylated late viral protein (125,000 molecular weight). The other monoclonal antibody (19.1) with neutralizing activity, reacted with membrane antigens of infected cells and with the varicella-zoster virus envelope and immunoprecipitated two late major viral glycoproteins (gp1 and gp3). Synthesis of the 125,000-molecular-weight protein, gp1, and gp3 began at 20 to 22 h postinfection, 2 h after the peak of viral DNA synthesis, and continued until 29 h postinfection, when the first progeny virus appeared in infected cells. Pulse-chase experiments showed that during pulse-labeling, only gp1 was detected, whereas during the chase period, gp1 as well as gp3 was detected in infected cells. Under nonreducing conditions, gp3 migrated in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a 130,000-molecular-weight protein as compared with the 62,000-molecular-weight species obtained when gels were resolved under reducing conditions. This finding indicates that gp3 is a dimer that is disulfide linked.

Varicella-zoster viral glycoproteins analyzed with monoclonal antibodies.

Monoclonal antibodies to varicella-zoster virus were used to study viral glycoproteins by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Based on the viral glycoproteins immunoprecipitated, the five monoclonal antibodies fell into three groups. Two antibodies, 4B7 and 8G9 (group 1), immunoprecipitated a single glycoprotein of molecular weight (MW) 118,000 (118K glycoprotein) and had high neutralizing activity in the absence of complement. One antibody, 3C7 (group 2), which lacked neutralizing activity, immunoprecipitated two glycoproteins of MWs 120,000 and 118,000 and a glycoprotein giving a diffuse band in the region of 64,000 to 65,000. Pulse-chase experiments and experiments with monensin as an inhibitor of glycosylation suggested that the 120K polypeptide was derived by glycosylation of the 118K polypeptide and that a 43K antigen was processed into the 64 to 65K glycoprotein. Two antibodies, 3G8 and 4E6 (group 3), both had neutralizing activity only in the presence of complement, and both immunoprecipitated at least five polypeptides, with MWs ranging from 50,000 to 90,000. Antibody 3G8 was isotype immunoglobulin G2b (IgG2b), and its immunoprecipitating activity was stronger than that of 4E6, which was isotype IgG1. Pulse-chase experiments with antibody 3G8 showed that lower-MW glycopeptides chased into three polypeptides of MWs 90,000, 80,000, and 60,000 by 24 h. Immunoprecipitation experiments with antibody 3G8 on infected cells treated with glycosylation inhibitors 2-deoxyglucose, monensin, and tunicamycin, suggested that a prominent, early-appearing 70K polypeptide may have been processed into the glycoproteins of higher MWs and that the 60K polypeptide may have been derived by glycosylation of polypeptides of lower MWs.

Glycoprotein gp118 of varicella-zoster virus: purification by serial affinity chromatography.

Glycoprotein gp118, one of the major glycosylated proteins specified by varicella-zoster virus, is biologically of great importance since it possesses an epitope which elicits a complement-independent neutralizing antibody response. To purify this glycoprotein from a Nonidet-solubilized extract of varicella-zoster virus-infected cells, we examined its affinity to a variety of ligands, including two lectins--concanavalin A and Lens culinaris, Cibacron blue and heparin, and finally an immunoadsorbent anti-gp118 monoclonal antibody. By serial affinity chromatography on three different columns consisting of, respectively (i) Cibacron blue dye-Sepharose, (ii) L. culinaris-Sepharose, and (iii) anti-gp118 murine monoclonal antibody bound to CNBr-activated Sepharose, we isolated varicella-zoster virus-specific gp118 essentially free of contamination by any other radiolabeled viral or cellular polypeptide. The fold purification was estimated at 1,025 and the percent recovery at 13.6. On the basis of its chromatographic properties, gp118 appeared to contain mainly asparagine-linked, biantennary, complex-type, and hybrid-type oligosaccharides.

Varicella-zoster virus-specific gp140: a highly immunogenic and disulfide-linked structural glycoprotein.

A 140,000-dalton disulfide-linked glycoprotein (gp140) specified by varicella-zoster virus (VZV) in infected cultured cells was identified and precipitated by two murine monoclonal antibodies (VZ-151 and VZ-158). When analyzed under reducing conditions by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gp140 was cleaved predominantly into a 66,000 lower-molecular-weight product (gp66). This protein was classified as a viral structural component, since it was observed in the polypeptide profile of metrizamide gradient-purified enveloped virions. By immunofluorescence analyses with a monoclonal antibody probe, gp140 expression was documented to be highly conserved both within cultured cells inoculated with homologous (VZV-Oka) and heterologous (VZV-32) strains and in infected human tissues from chicken pox and zoster patients. That the glycoprotein was highly immunogenic was confirmed by the presence of high-titer anti-gp140 antibody in the sera of both hyperimmunized laboratory animals and naturally infected humans. Temporally, the humoral response to gp140 following primary VZV infection preceded that against the other viral glycoproteins. These studies describe, therefore, an immunogenic, disulfide-linked viral structural glycoprotein, which must be included among the other five previously described VZV-specific fucosylated species--gp118, gp98, gp62, and gp45.

Purification and molecular anatomy of the varicella-zoster virion.

Varicella-zoster virus (VZV) infected cell cultures were harvested and sonically disrupted when cytopathic effect was advanced. Infectious cell-free virus in the sonicates, as well as that in the culture medium, was further concentrated by precipitation with 8% (w/v) polyethylene glycol in the presence of high salinity (0.5 M). The virus-enriched pellet was layered onto 15-45% linear metrizamide gradients and sedimented for 18 h at 70,000 g. Of the three visible bands (designated upper, middle and lower), the middle band at a buoyant density of 1.156-7 g/cm3 was enriched for enveloped virions. Electron microscopic enumeration of particles demonstrated a total of 10.04 log10 enveloped particles and 8.26 log10 unenveloped particles from middle bands representing the yield from a 150 cm2 VZV-infected monolayer. Fractionation of radiolabeled virion preparations by SDS-PAGE revealed 30 polypeptides between 30 and 200 kilodaltons (K) with a total mol wt of 2,240,000. Prominent structural polypeptides included the major capsid protein (155K) and three glycoproteins--62K, 98K and 118K. Certain polypeptides better labeled by [14C] amino acids than by [35S] methionine included a higher mol wt polypeptide (174K) and 45K protein comigrating with actin. Immune precipitation of a Nonidet-extracted virion fraction again demonstrated the three major glycoproteins, as well as the 155K and 45K polypeptides. Comparison of structural polypeptides with the 16 constituents of the VZV-specific immunoprecipitation profile identified at least one polypeptide (145K) which was not represented in the virion and assumed, therefore, to be nonstructural.

Polypeptides of varicella-zoster virus (VZV) and immunological relationship of VZV and herpes simplex virus (HSV).

Varicella-zoster virus (VZV), labelled with [35S]methionine or [14C]glucosamine, was purified by centrifugation through sucrose gradients followed by equilibrium centrifugation in CsCl, and analysed by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). At least 32 polypeptides ranging in mol. wt. from approx. 280 X 10(3) to 21.5 X 10(3) (280K to 21.5K) and six glycopeptides ranging in mol. wt. from approx. 115K to 45K (gp1 to gp6) were found in the virion. The immunological relationship of VZV and herpes simplex virus (HSV) was investigated. In neutralization (NT) tests, no cross-neutralization was observed between VZV and HSV-1 or -2. In fluorescent antibody staining, however, a cross-reaction was observed between VZV- and HSV-1-infected human embryonic lung (HEL) cells and heterologous antiserum. When cross-reactions were investigated by immunoprecipitation followed by SDS-PAGE, several cross-reacting polypeptides were discovered. Cross-reacting glycopeptides of 64K (gp3) and 55K (gp5) were isolated from VZV-infected cell lysates by affinity column chromatography to immobilized HSV-1 antibodies.

Studies on the polypeptides of varicella-zoster (V-Z) virus. 1. Detection of varicella-zoster virus polypeptides in infected cells.

Virus-induced polypeptides in cells infected with varicella-zoster virus (VZV) were analyzed by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and autoradiography. When human embryonic lung (HEL) cells infected with the Oka strain of VZV were labelled with 35S-methionine or 14C-glucosamine from 40 hr to 46 hr after infection, at least 18 VZV-induced polypeptides and 10 glycoproteins could be identified in the infected cells. The molecular weights of the polypeptides and glycoproteins ranged from about 145,000 to 23,000, and from about 105,000 to 48,000, respectively. Lysates of VZV-infected cells were treated with specific antisera prepared in green monkeys or guinea-pigs, and analysed by SDS-PAGE and fluorography. In all, 33 polypeptides (with molecular weight of about 145,000 to 22,000) and 13 glycoproteins (molecular weight, about 105,000 to 38,000) were found in the immunoprecipitates. None of these polypeptides and glycoproteins were detected when infected cells cultured in the presence of phosphonoacetic acid (PAA) were treated in the same way.