t antigen synthesis and resistance to interferon in human adenovirus type 12 infected chick cells.tye specific t antigen formation has been demonstrated in primary and secondary chick embryo cells (cec) infected with adenovirus type 12. the frequency of cells synthesizing t antigen was closely dependent on the multiplicity of infection (moi). at a moi of 2.85 tcd50 per cell, t antigen was formed in 50% of cells. cycloheximide inhibited t antigen formation while cytosine arabinoside had no such effect. cec infected with adenovirus 12 produced interferon and t antigen, both appearing early and ...197723662
revertants of adenovirus type-12-transformed hamster cells have lost part of the viral genomes. 197990022
adenovirus type 12 plaque formation in vero cells. 1979112357
differential cell membrane labilizing effect of adenovirus type 5 and 12 observed during productive and abortive infection.culture fluid of human epitheloid (hep-2) cells was examined for extracellular lactate dehydrogenase activity as an indicator of cell damage during a 48 h period in which virus replication and changes in cell morphology occurred. uninfected and adenovirus type 5-infected cells had the same levels of extracellular enzyme activity both before and after the appearance of morphological changes in cells due to virus infection, whereas adenovirus type 12-infected cells showed increased extracellular e ...1979119136
in vitro studies on target cells of oncogenic adenoviruses in hamster brain. ii. in vitro transformation of brain cells of hamsters at various ages by human adenovirus type vitro transformations of brain cells of hamsters of various ages were examined after the administration of human adenovirus type 12 (ad 12) to determine the type and origin of the target cell. hamster brain cells at all examined ages were transformed by ad12. although the virus was not isolated, virus specific tumor antigen was demonstrated in the transformed cells. the histological features of tumors that developed by transplantation of transformed cells closely resembled ad12-induced brain ...1975132084
target cells of human adenovirus type 12 in subtentorial brain tissue of newborn mice. i. cyto-histomorphologic and immunofluorescent microscopic studies.human adenovirus type 12 (ad 12) was inoculated through subtentorial route into inbred newborn mice (c3h/bifb/ki), and sequential changes of the brain and tumor induction were examined by histological and immunofluorescent methods. two days after virus inoculation, ad 12 specific tumor antigen (fluorescent t-antigen) appeared in the cells of ependymal and subventricular matrix layers, choroid plexuses and leptomeninges in the subtentorial as well as the supratentorial brains. after 10 days, thes ...1976136869
target cells of human adenovirus type 12 in subtentorial brain tissue of newborn mice. ii. cytomorphologic and immunofluorescent microscopic studies in vitro.the normal subtentorial brain cells of newborn mice (c3h/bifb/ki) were cultured by the monolayer culture technique. the first subculture was inoculated with human adenovirus type 12 (ad 12) in an attempt to achieve the transformation of the brain cells. normal cultured cells were morphologically divided into astrocytic cells (ac-1 cells and ac-2 cells), immature brain cells including undifferentiated cells (ud cells) and glioblastic cells (gb cells), and fibroblastic cells (fb cells). fluorescen ...1976137655
fetal antigens associated with adenovirus 12 mouse tumors.the fetal antigen(s) of c3h/bfb/ki mouse tumor cells induced by adenovirus type 12 was examined by transplantation resistance, local adoptive transfer and in vitro cell-mediated microcytotoxicity tests. mice immunized with 8 to 9-day gestation fetal cells showed weak resistance to the challenge of small numbers of tumor cells, but immunization with 13 to 14-day gestation fetal cells did not confer transplantation immunity. local adoptive transfer of multiparous pregnant mouse spleen cells mixed ...1976138333
control of nuclear division in sv40 and adenovirus type 12 transformed mouse 3t3 cells.untransformed, non-tumorigenic mouse cells respond to cytochalasin b (cb) with limited nuclear division. balb/c mouse embryo fibroblasts (mef) and both balb/c 3t3 and swiss 3t3 cells become binucleated in the presence of cb and cells with three or more nuclei are very rare or undetectable. mef are diploid (40 chromosomes) and 3t3 cells are subtetraploid (74-76 chromosomes). transformation of mef by sv40 produces a dramatic change in response to cb. these cells, which contain sv40 t-antigen, beco ...1975166945
[viruses and brain tumors (author's transl)].this brief review paper deals mainly with oncogenic dna viruses originally isolated from human patients, i.e., human adenoviruses and human papova jc viruses. human adenovirus type 12 was first isolated in 1953 in cell cultures derived from the adenoids of infected children. since then, 32 antigenic types of human adenovirus have been identified. at least eight serotypes (12, 18, 31, 3, 7, 14, 16, and 21) are now known to be capable of producing tumors in newborn rodents. a direct causal relatio ...1975172819
adenovirus type 12 infection of defined mouse-human hybrid cell clones.human adenovirus type 12 does not multiply in mouse cells; only viral t-antigen is detected. mouse-human cell hybrid clones containing human chromosomes a3, b5, c7, c11, c12, d14, e17, f19 and f20, support synthesis of adenovirus dna and capsid antigens.1976174935
infection of newborn taiwan monkeys (macaca cyclopis) with human adenovirus type 12 and simian virus 40.for testing biological response of newborn taiwan monkeys to infection of human adenovirus type 12 (ad12) and simian virus 40 (sv40), 40 newborn taiwan monkeys were inoculated with ad12, ad12, plus sv40, ad12 supplemented with ad12-induced hamster tumor tissue (ad12 tumor) or control specimens (hela or african green monkey kidney cell lysate). among them 26 survived including 8 newborn monkeys inoculated with control specimens. the survivors were observed for 4 years but no tumor was produced. t ...1975181217
promotion of incidence of adenovirus type 12 transplantable tumors by carrageenan, a specific antimacrophage agent.carrageenan, a sulfated polygalactose with known macrophage-toxic properties, was used to ascertain the role of macrophages in resistance to adenovirus type 12 transplantable tumors. a single ip injection of 5 or 10 mg carrageenan led to increased incidence and more rapid growth of tumors in c3h mice. carrageenan was most effective if given 1 day before tumor inoculation; the effectiveness decreased with increasing intervals before or after tumor cell injection. the macrophage stabilizer poly-2- ...1977191626
cell-mediated immunity assayed by 51cr release test in mice infected with mouse adenovirus.immune spleen cells (isc) from mice immunized with a sublethal dose of mouse adenovirus (m-ad) were shown by the 51cr release test to be cytotoxic to target mouse embryonic cells or lymphoid cells infected with m-ad. the number of isc required for release of statistically significant amounts of 51cr from target cells varied from one sample to another, ranging from 5 to greater than or equal to 30 isc per target cell. when 24-h-infected mouse embryonic cells were used as targets, the release of 5 ...1978208968
adenovirus type 12 gene 401 function and maintenance of transformation.rat (3y1) and hamster embryo brain cells were transformed by wild-type adenovirus type 12 or the dna-minus temperature-sensitive mutant ts401. the ts401-transformed 3y1 cells, but not the wild-type transformants, displayed a temperature-sensitive response with respect to the following characteristics of the transformed phenotype: morphology, saturation density, growth rate, cloning in soft agar, colony formation on plastic at low cell densities in 1% serum medium, and the t antigen(s). temperatu ...1979219220
adenoviral meningoencephalitis in a patient with lead toxicity.adenovirus type 12 was recovered from the csf of a 36-year-old woman with adenoviral meningoencephalitis and lead toxicity. the serum level of lead was 199 micrograms/dl and the csf level was 7 micrograms/dl. after therapy with edetate disodium calcium (calcium disodium versenate), she had an uneventful recovery. the possibility of exacerbation of lead poisoning with encephalopathy due to adenovirus type 12 meningoencephalitis is raised.1979222248
interferon induction by adenoviruses.all human, simian, bovine and avian adenovirus types tested so far and the canine hepatitis virus induce interferon production in chick cells. this finding indicated this property to be characteristic for viruses belonging to the adenovirus group. trypsin treatment, which had no effect upon the infectivity, diminished or eliminated the interferon-inducing abilities of crude adenoviruses, and thus the need for a trypsin-sensitive protein in interferon induction was suggested. t antigen and interf ...1979223139
structure and function of adenovirus type 12 defective virions.purified human adenovirus type 12 preparations contain defective virions with a lighter density. these defective virions were isolated, and their biological functions and dna were characterized. they can induce early and late antigens in infected cells and tumors in newborn hamsters with similar efficiency as complete virions. the majority of the dna molecules from light virions contain deletions mapping near 16% from the left-hand end of the genome. mechanisms for the generation of these molecu ...1979232175
primitive neuroectodermal tumor (neuroepithelioma) of spinal nerve root -- report of an adult case and establishment of a cell line.a case of primitive neuroectodermal tumor arising in the cervical nerve root of a 28-year-old man is presented. histologically, the tumor was characterised by proliferation of primitive neuroectodermal cells and formation of numerous homer-wright type rosettes. a cell line (nagai line) was established from the tumor. electron microscopic examination of nagai cells revealed numerous microrosette formation with microvilli-like cytoplasmic processes projecting into the central lumina. neurosecretor ...1979233287
physico-chemical characteristics of interferons induced by human adenovirus in chick fibroblasts and leucocytes.the physico-chemical characteristics of interferons with different anti-viral activities produced in chick fibroblast cells and leucocytes in response to the human adenovirus type 12 were investigated. the molecular weights of interferons produced by chick fibroblasts and leucocytes were similar: the main anti-viral activity was found at 27000 and 32000 and a low-titered shoulder at 28000 and 23000 respectively. under our experimental conditions no oligomeric structure of interferons could be de ...1975241243
retinoblastoma-like neoplasm induced in c3h/bifb/ki strain mice by human adenovirus serotype 12.eighty newborn c3h/bifb/ki strain mice received a single intraocular inoculation of 0.002--0.003 ml of 10(8.0) tcid 50/0.1 ml human adenovirus 12 (ad 12), within 24 h after birth. forty mice survived and in seven of these (17.5%) a solid retinoblastomalike neoplasm developed between 64 and 236 days. the tumors have been successfully cultured and also transplanted subcutaneously into syngeneic hosts. morphologically, all tumors revealed characteristic features of retinoblastoma associated with th ...1977331842
helper factor(s) for growth of adeno-associated virus in cells transformed by adenovirus 12.evidence is presented that a helper factor(s) for growth of adeno-associated virus (aav) is present in cells transformed by adenovirus type 12 (ad12). the growth of aav was observed in heterokaryons formed by fusion of human kb and ad12-transformed rodent cells by using ultraviolet-inactivated sendai virus without coinfection of cells with adenovirus. the presence of the helper factor(s) for aav growth in rat cells transformed by the ecori-c fragment or the hindiii-g fragment of ad12dna suggests ...1977337298
comparative study by immunofluorescence of t and p antigens induced by adenovirus type 12 in permissive and nonpermissive cells.the development of adenovirus type 12 t antigen and of the complex of antigenic early proteins designated as p antigen was studied by immunofluorescence in productively infected kb cells and abortively infected rk-13 cells. t antigen is detected in both cell types very early in infection. in kb cells it presents the well known pattern of nuclear dots and flecks but in rk-13 cells at the time of maximum abundance, 18 hours p.i., t antigen forms a net of long filaments that fills the nucleus. late ...1978367317
identification of adenovirus type 12 candidate transformation proteins by radioimmunoprecipitation with antisera to ecori-c-fragment transformed cells. 1979375576
requirement of adenovirus type 12 gene 401 function for initiation of virus dna synthesis.the highly oncogenic human adenovirus type 12 temperature sensitive mutant. h12ts401, is unable to maintain the growth characteristics of transformed cells at the non-permissive temperature. in lytic infection, the 401 gene function is required to produce virus dna. in the present study, virus dna synthesized in ts401-infected human cells after temperature shift-up was characterized. no apparent suppression of dna chain elongation or ligation occurs at the non-permissive temperature, but, as sho ...1979430034
cell origin of human adenovirus type 12-induced subcutaneous tumor in syrian hamsters.single subcutaneous inoculation of human adenovirus type 12 (ad.12), 0.05-0.1 ml of 10(8.0) tcid50 hek cells/0.1 ml, was made on the back of 0-day-old hamsters. in 21 of 25 hamsters (84.0%), multiple solid tumors developed close to the inoculation site within 3 months. no control hamsters developed tumors. tumor histopathology revealed the characteristic homer wright rosettes of neuroblastoma. ad. 12-specific tumor antigens were demonstrable in both the primary and the cultured tumor cells by th ...1979442984
[brain tumors induced by human adenovirus type 12 in c3h/he mice (author's transl)]. 1979454556
adenovirus type 12 va rna. i. synthesis in productive infection and gene mapping. 1979462796
a rapid screening for the specific dna sequence: analysis of transforming dna segments in adenovirus-transformed cells.the viral dna sequences in cells transformed by adenovirus type-12 (ad12) dna fragments were investigated by spot hybridization, a detection by autoradiography of nucleic acid hybrids formed between cell dnas spotted on a membrane filter and various nick-translated ad12 dna fragments. in cy1 cell line, a rat cell line transformed by the ecori-c fragment (left hand 16%), all of the hindiii fragments included in the ecori-c fragment are shown to be present. in gy1 cell line, a rat cell line transf ...1979467887
in vitro translation of adenovirus type 12-specific mrna isolated from infected and transformed cells.the early and late gene products of human adenovirus type 12 (ad12), as well as the viral proteins synthesized in an ad12-transformed cell line, were identified by translation of viral mrna in an in vitro protein-synthesizing system. cytoplasmic rna was isolated from permissive kb or nonpermissive bhk cells infected with ad12 and from ad12-transformed ha12/7 cells. virus-specific rna was selected by hybridization to ad12 dna covalently bound to cellulose. viral rna was then translated in a fract ...1979480453
adenovirus type 12 tumor antigen. ii. immunoprecipitation of protein kinase from infected and transformed cells by antisera to t antigen and some normal rat sera. 1979494492
tumor-specific transplantation and surface antigen in cells transformed by the adenovirus 12 dna fragments.adenovirus type 12 (ad 12) tumor-specific transplantation antigen (tsta) and the surface (s) antigen were examined using rat cells transformed with ad 12 dna and its fragments. wy3 (3yl cells transformed with ad 12 whole dna), cyl (3yl cells transformed with the ecori-c fragment of ad 12 dna), and gy cells (3yl cells transformed with the hindiii-g fragment of ad 12 dna) contained tsta and s antigen, but hy cells (3y1 cells transformed with the bpai-h fragment of ad12 dna) did not. these results ...1979494494
transforming dna sequences in rat cells transformed by dna fragments of highly oncogenic human adenovirus type 12.rat cell lines tranformed by viral dna fragments, ecori-c and hindiii-g, of adenovirus type 12 dna were analyzed for the viral transforming dna sequences present in cell dnas. cell lines transformed by the ecori-c fragment of adenovirus type 12 dna (leftmost 16.5% of the viral genome) contain most of the hindiii-g sequences of the hindiii-g fragment, but at a different frequency depending on the portions of the fragment. the sequence of the acci-h fragment of adenovirus type 12 dna (the left par ...1979501799
transcription of the genome of adenovirus type 12. v. kinetic and size-class analyses of nuclear and messenger rna in productive human kb cells productively infected with adenovirus type 12 (ad12) the kinetics of synthesis of ad12-specific rna were investigated. using 2 h labelling periods, striking differences were observed in the time course and the rate of synthesis of virus rna comparing the nuclear, cytoplasmic and polysomal rna fractions. a protracted onset of virus rna synthesis was followed by an exponential increase between 15 and 40 h p.i.; reaching a maximum at 40 to 45 h p.i., the fraction of the newly synt ...1979528981
susceptibility of ad12-transformed s (+) and s (-) mouse cells to cell-mediated immunity in vitro.adenovirus type 12 (ad12)-transformed mouse cells were examined for their susceptibility to cell-mediated immunity in vitro, with respect to the activity of the virus-specific surface (s) antigen in the cells. a transformed cell line, c57at1, was established from embryonic cells of c57bl/6 mice by ad12 infection. in fluorescent antibody tests, the transformed cells were positive for the s antigen when the cells were maintained as cultures, whereas when the cells were grown as tumors in animals t ...1979530102
purification of adenovirus type 12 tumor antigen from transformed hamster cells. 1977557257
abortive and transforming infection of rat cell line 3y1 by adenovirus type 12.human adenovirus type 12 underwent an abortive and transforming infection in clonal cultures of rat cell line 3y1. the frequency of transformation was proportional to the dose of input virus. the ratio of pfu to transforming units was 1.1 x 10(5).1978565416
characterization of adenovirus type 12 tumour antigen produced in chick fibroblasts.tumor (t) antigen was characterized in non-permissive chick fibroblasts and permissive hep-2 cells infected with ad12 either in the presence or in the absence of cytosine arabinoside. antiserum against t antigen specifically immunoprecipitated two polypeptides of apparent mol. wt. 50 000 and 11 000.1978569186
hyperthermia and host-cell reactivation of adenovirus 12.exposure of cultured human fibroblasts to hyperthermia delayed the host-cell reactivation of uv-irradiated human adenovirus type 12 (ad12). the experimental design consisted of irradiating human ad12 with uv doses ranging from 180 to 1800 ergs/mm2, infecting human cell populations at 37 degrees c, exposing the infected cells for 7 h to 39.5 degrees c and 41.8 degrees c, returning them to 37 degrees c and estimating the frequency of cells with intranuclear viral inclusion bodies (ib) 41 and 89 h ...1978657003
isozymic forms of some energy metabolism enzymes during oncovirus-induced cell transformation.kinetic studies of changes in isozymic forms of hexokinase, lactate and malate dehydrogenase and in total hexokinase activity during viral carcinogenesis were carried out. the test systems were rat embryo fibroblasts infected with an oncogenic variant of human adenovirus type 12 and an infectious adenovirus type 6, intact ref cultures in different stages of growth (log and stationary phase), and hamster sarcoma a12 and rat reticulosarcoma 321-rrs cell cultures. molecular isozymic forms of the st ...1978658548
adenovirus type 12 tumor antigen. i. separation from dna polymerase alpha and immunoprecipitation of tumor-antigen polypeptides. 1978664211
deletions and insertions in adenovirus type 12 dna after viral replication in vero cells. 1978664232
adenovirus type 12 gene 401 function in transforming infection.the temperature-sensitive dna-minus mutant, h12ts401, transformed two to eight times more hamster embryo cells than wild-type 12 adenovirus at 38.5 degrees c, but was unable to establish transformation of cultures of hamster embryo brain and rat 3y1 cells at 41.5 and 40 degrees c, respectively. another h12ts406 dna-minus mutant was not defective in cell transformation at these restrictive temperatures. both mutants, however, induced t-antigen and cell dna synthesis after infection of 3y1 cells a ...1978671589
patterns of integration of viral dna sequences in the genomes of adenovirus type 12-transformed hamster cells.the patterns of integration of the viral genome have been analyzed in four hamster cell lines transformed by adenovirus type 12 (ad12). it has previously been shown that in each of the cell lines ha12/7, t637, a2497-2 and a2497-3, the viral genome persists in multiple copies, and that different parts of the viral dna are represented non-stoichiometrically (fanning and doerfler, 1976). all four cell lines are oncogenic when injected into hamsters. the dna from each of the cell lines was extracted ...1978688383
morphological revertants of adenovirus type 12-transformed hamster cells.morphological revertants have been isolated from one line of adenovirus type 12-transformed hamster cells. this line, t637, is oncogenic in hamsters and contains multiple copies of the virus genome per cell. different parts of the virus genome are represented in non-stoichiometric amounts and the virus dna persists in the cells in an integrated form. the pattern of integrated virus genomes has been determined by the blotting technique. in the t637 line, morphological revertants arise spontaneous ...1978690612
a variant of adenovirus 12 producing cytoplasmic accumulation of capsid proteins.a variant of adenovirus type 12 (r-ad12) has been isolated by infecting a clonal line of normal rat kidney cells (nrk) with wild-type adenovirus 12. although r-ad12 failed to produce infectious progeny virions when cycled a second time through nrk cells, it nevertheless retained the ability to code for virus structural proteins that accumulated in the cytoplasm.1978690616
alterations in surface glycoproteins and level of sialyltransferase activity of human embryo kidney cells infected with oncogenic adenovirus type 12.human embryo kidney (hek) cells infected with adenovirus type 12 and its cytocidal mutants (cyt) synthesized different glycoproteins respectively on the cell surface at the early stage of infection. furthermore, a less and a highly tumorigenic cyt mutants synthesized different glycoproteins. the level of sialyltransferase activity in the microsomes of hek cells was increased when cells were infected with adenovirus type 12. it was confirmed that there was a positive correlation between the sialy ...1978694922
tumor-specific transplantation antigen(s) of bovine against bovine adenovirus type 3-induced primary or transplantable tumors was studied in hamsters immunized with bovine adenoviruses, human adenovirus type 12 (a-12), simian adenovirus type 7 (sa7), or chicken-embryo-lethal-orphan (celo) virus. newborn hamsters inoculated with 2.3 times 10-5 plaqueforming units of bovine adenovirus type 3 were given injections of bovine serotypes 1, 2, or 3 during the latent period of tumor development. no hamsters immunized with type 3 and only 47% o ...1975803562
identification of early proteins induced by highly oncogenic human adenovirus 12 during lytic infection and in hamster tumors. 1977843353
multiple copies of human adenovirus 12 genomes are integrated in virus-induced hamster tumors.tumors induced in hamsters by highly oncogenic human adenovirus 12 contain multiple copies of 90 to 100% of the viral genome in an integrated form.1977853566
transformation of a rat cell line by an adenovirus type 12 dna fragment. 1977898675
adenovirus type 12 dna sequences in primary hamster five out of six primary hamster tumors induced by adenovirus type 12, less than 55% of the adenovirus type 12 genome is present. various fragments of the integrated viral dna were present in non-equimolar amounts.1977904032
solubilization and purification of surface antigen of cells transformed by adenovirus type 12. 1976944966
synthesis of va rna in productive and abortive infections with adenovirus type 12. 1976982836
transcription of the genome of adenovirus type 12. iii. maps of stable rna from productively infected human cells and abortively infected and transformed hamster cells.the adenovirus type 12-specific mrna and the stable nuclear rna from productively infected kb cells, early postinfection, from abortively infected bhk-21 cells, and from the adenovirus type 12-transformed hamster lines t637 and ha12/7 have been mapped on the genome of adenovirus type 12. the intact separated heavy (h) and light (l) strands of adenovirus type 12 dna have been used to determine the extent of complementarity of the mrna or nuclear rna from different cell lines to each of the strand ...1976988193
freeze-etching observation on the nucleus of hela-s3 cell infected with adenovirus type 12. 19761027897
dna methylation in adenovirus, adenovirus-transformed cells, and host cells.dnas of adenovirus type 2 and type 12 contain low amounts of methylated bases (0.01 and 0.02% n6-methyl-adenine per adenine, if any, and 0.04 and 0.06% 5-methylcytosine per cytosine for type 2 and type 12, respectively), whereas the dna of the mammalian host cells contains much more 5-methylcytosine (3.57% for human kb cells). the dna of hamster cells transformed by adenovirus type 12 contains 3.11 and 3.14% 5-methycytosine (ha12/7 and t627 cells, respectively), whereas the dna from untransforme ...19761069277
complementation of human adenovirus type 5 ts mutants by human adenovirus type 12.temperature-sensitive mutants of type 5 adenovirus belonging to eight complementation groups were complemented in mixed infection by type 12 adenovirus, whereas mutants of 7 other groups were not enhanced. in some crosses, phenotypic mixing took place. no evidence of recombination between type 5 ts mutants and type 12 was found.19751113379
isolation and characterization of adenovirus type 12 dna binding proteins. 19751162902
transcription of the genome of adenovirus type 12. i. viral mrna in abortively infected and transformed baby hamster kidney (bkh-21) cells abortively infected with adenovirus type 12, polysome-associated, virus-specific rna could be detected starting 5 to 7 h after infection. the amount of this rna reached a maximum between 10 to 12 h after infection and continued to be synthesized at a reduced level until late in infection (48 to 50 h.). in bhk-21 cells transformed by adenovirus type 12 (hb cells), 0.26% of the polysome-associated mrna was virus specific. the size of the virus-specific mrna is ...19751167602
virus specific rna in hamster cells abortively infected with human adenovirus type 12. 19751171554
transcription of the genome of adenovirus type 12. viral mrna in productively infected kb human kb cells productively infected with adenovirus type 12, viral dna replication starts between 12 and 14h postinfection. virus-specific, polysome-associated mrna was investigated early (6-8h) and late (26-28h) after infection. most of the viral mrna was polyadenylated and accounted for 0.46% and 24.1% of the mrna synthesized early and late postinfection, respectively. the viral-specific mrna isolated both early and late after infection falls into several distinct size-classes, ranging in ...19751183441
[detection of adenovirus type-12 in sarcomas induced by this virus in hamster].cells of transplantable sarcomas primarily induced in hamsters with adenovirus, type 12, produced persistantly this virus in an infective form. in sera of sarcomabearing hamsters virus-neutrolizing antibodies and antibodies to t-antigen of tumors were revealed. the presence of t-antigen in cells of all types of sarcoma a-12 was demonstrated by means of immunofluorescence, as well as the absence of a specific luminescence of surface membranes of a-12 mml sarcoma cells, obtained from pulmonary mic ...19751189365
replication of human kb cell dna after infection by adenovirus type 12. 19751207745
gene functions of adenovirus type 12: synthesis of nuclear acidic proteins in human embryo kidney cells. 19751208875
[isoenzymes of lactate and malate dehydrogenases in nuclei of rat embryo fibroblasts infected with oncogenic adenovirus type 12].the isoenzymatic spectrum of lactatedehydrogenase (ldg; l-lactate: nad-oxireductase; ec and malatedehydrogenase (mdg; 1-malate: nad-oxireductase; ec in nuclei of rat embryo fibroblast cells infected with adenovirus type 12 was studied at 3, 5, 8, 18 and 24 days of cultivation. the nuclei were isolated according to the method of showo et al. modified by zbarsky and georgiev. proteins were fractionated by disc electrophoresis in polyacrylamide gel. in the course of oncovirus-ce ...19751241176
temperature-sensitive mutants of type 12 adenovirus defective in a late function: protein synthesis and evidence for recombination between mutants in complementation group d.four temperature sensitive mutants of adenovirus type 12, classified into complementation group d, synthesize most or all of the late virus-specific polypeptides at the restrictive temperature, as shown by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. infections by these mutants under restrictive conditions apparently result in some over production of the virion hexon polypeptide compared to wild type infection. genetic recombination between the four mutants has been demonstrated. ...19761245844
chromosome alterations contribute to neoplastic progression of transformed rat embryonal fibroblasts.three types of transformants derived from rat embryonal fibroblasts (refs) corresponding to the different progressional stages were obtained: tf1 (human papillomavirus type 16 e7 (hpv16 e7) transfection alone) and tf2 (e7 plus adenovirus type 12(ad12) e1b were immortalized, tf3 (e7 plus adenovirus type 5 (ad5) e1b) was anchorage-independent but not tumorigenic, and tf4 (e7 plus ej-ras) was tumorigenic. cytogenetic investigations revealed that the cells carrying specific chromosomal abnormalities ...19921309485
highly efficient focus formation by rous sarcoma virus on adenovirus type 12 e1a-transformed rat 3y1 cells.when rat 3y1 cells were infected with rous sarcoma virus (rsv) variant sr-rsv-d(h), many 3y1 cells acquired a stable provirus but only few of them formed transformed foci. in contrast, 12e1ay cells (3y1 cells expressing the adenovirus type 12 [ad12] e1a protein) formed transformed foci upon rsv infection with the same high frequency as did chicken embryo fibroblast cells. this enhancement of focus-forming efficiency was specifically observed in 3y1 cells expressing ad12 e1a protein but was not o ...19921310757
driving adenovirus type 12-transformed balb/c mouse cells to express high levels of class i major histocompatibility complex proteins enhances, rather than abrogates, their tumorigenicity.the tumorigenicity of adenovirus type 12 (ad12)-transformed cells has been attributed to the low levels of class i major histocompatibility complex (mhc) protein expression by these cells. these levels of class i proteins are thought to be below the threshold critical for cytotoxic t-lymphocyte recognition, a process that may be involved in tumor cell immunosurveillance. we have used gene transfer experiments to investigate the role played by class i protein expression in the tumorigenicity of a ...19921313906
restriction endonuclease patterns of adenovirus type 12 and 18.restriction endonuclease analysis using 10 restriction enzymes was performed on six and three wild isolates of adenovirus (ad) type 12 and 18, respectively. among the ad12 strains, five dna variants could be identified. the degree of pairwise comigration of restriction fragments suggests a high degree of genomic diversity within ad12. the wild isolates of ad18, on the other hand, displayed a low degree of genetic variability and comprised one dna variant closely related to the prototype strain. ...19921331143
activation of the mouse proliferating cell nuclear antigen gene promoter by adenovirus type 12 e1a proteins.a plasmid carrying the 5'-flanking region (-1584 to +47 with respect to the transcription initiation site) of the mouse proliferating cell nuclear antigen (pcna) gene was fused with the chloramphenicol acetyltransferase (cat) gene, and then cotransfected into mouse n18tg2 cells with expression plasmids for the adenovirus type 12 e1 genes. expression of e1a gene products elevated the cat expression by 5- to 9-fold, but expression of the e1b gene product did not. rnase protection analysis revealed ...19921353754
down-regulation of the major histocompatibility complex class i enhancer in adenovirus type 12-transformed cells is accompanied by an increase in factor transformed cells, the e1a gene of adenovirus type 12 (ad12) represses transcription of class i genes of the major histocompatibility complex. the tumorigenic potential of ad12-transformed cells correlates with this diminished class i expression. in contrast, the e1a gene of the nontumorigenic ad5 does not affect class i expression. we show here that a transfected reporter chloramphenicol acetyltransferase plasmid driven by an h-2k promoter (-1049 bp) was expressed at much lower levels in ad1 ...19921433502
negative regulation of the major histocompatibility complex class i enhancer in adenovirus type 12-transformed cells via a retinoic acid response cells transformed by the highly oncogenic adenovirus type 12 (ad12), the viral e1a proteins mediate transcriptional repression of the major histocompatibility class i genes. in contrast, class i transcription is not reduced in cells transformed by the nononcogenic ad5. the decreased rate of class i transcription is, at least in part, the result of a reduced major histocompatibility complex class i enhancer activity in ad12-transformed cells and correlates with an increase in the levels of a d ...19921433503
adenovirus type 12 early region 1b proteins and metabolism of early viral mrnas.early region 1b (e1b) of human adenoviruses encodes two major proteins. the 19-kda polypeptide appears to prevent e1a-induced cytolysis and dna degradation. the larger e1b product of approximately 55 kda, which is essential for viral replication, plays a role in the accumulation and stability of viral mrnas and the late shutoff of host metabolism. for serotype 12 (ad12), this 482-residue (482r) protein is essential for viral dna replication. in the present report we have used a series of mutants ...19921448923
activation of the mouse dna polymerase beta gene promoter by adenovirus type 12 e1a proteins.a plasmid carrying the 5'-flanking region (-1852 to +33 with respect to the transcription initiation site) of the mouse dna polymerase beta gene fused with the chloramphenicol acetyltransferase (cat) gene was cotransfected into mouse n18tg2 cells with adenovirus type 12 e1 genes-expressing plasmids. expression of e1a gene products resulted in the elevation of the cat expression by 3 to 7 folds, but that of e1b gene product was much less effective. rnase protection analysis revealed that the acti ...19921534405
recombinant human adenoviruses containing hybrid adenovirus type 5 (ad5)/ad12 e1a genes: characterization of hybrid e1a proteins and analysis of transforming activity and host range.hybrid adenovirus type 12 (ad12)/ad5 e1a genes were constructed by homologous recombination in escherichia coli, a technique which offers several advantages over conventional mutagenesis for genetic analysis of proteins. in particular, functional differences between the proteins can be mapped by correlating the replacement of specific sequences with the acquisition of new properties, and there is no requirement for common unique restriction sites or polymerase chain reaction strategies to constr ...19921534849
acceleration of adenovirus replication and increased virion production by treatment with the steroid hormone 17 beta-estradiol.we report here that concentration of an estrogen known to promote enhanced transformation and to increase oncogenicity of rat embryo cells, accelerate the production and increase the yield of progeny virions in adenovirus type 12 (ad 12)-infected hep-2 cells. further, measurement of the incorporation of radioactive rna and dna precursors indicated that macromolecular synthesis in the estrogen-treated, infected cells was accelerated. possible explanations for this observation are discussed.19921584077
synergism between aphidicolin and adenoviruses in the induction of breaks at fragile sites on human chromosomes.infection of human embryonic kidney cells with adenoviruses results in the induction of gaps and breaks in cell chromosomes. with adenovirus type 12, cytogenetic damage is known to occur primarily at fragile sites on chromosomes 1 and 17. we have mapped adenovirus type 5-induced breaks and have observed that, although they occur on all chromosomes, they are localized primarily on bands where fragile sites have been mapped. the susceptibility of fragile sites to adenovirus led us to investigate t ...19911648440
cellular hypersensitivity to a synthetic dodecapeptide derived from human adenovirus 12 which resembles a sequence of a-gliadin in patients with coeliac disease.the human intestinal adenovirus serotype 12 (ad12) may be implicated in the pathogenesis of coeliac disease by virtue of immunological cross reactivity between epitopes shared by its early region e1b protein and a-gliadin. in the present study a synthetic dodecapeptide from the corresponding viral epitope (ad12e1b, residues 384-395) was tested for its effect on peripheral blood mononuclear cells from 22 treated and eight untreated patients with coeliac disease, 22 healthy subjects, 11 patients w ...19901696236
altered expression of adenovirus 12 dna-binding protein but not dna polymerase during abortive infection of hamster cells.replication of human adenovirus type 12 dna is blocked in abortively infected baby hamster kidney cells. the activity and accumulation of adenovirus 12 dna polymerase is equivalent in infected hamster and human cell extracts. however, the accumulation of adenovirus type 12 dna-binding protein is approximately 120-fold lower in extracts from infected hamster cells when compared to infected permissive human cells. this difference in accumulation is not due to replication of viral dna during produc ...19921534951
overexpression of the e1b 55-kilodalton (482r) protein of human adenovirus type 12 appears to permit efficient transformation of primary baby rat kidney cells in the absence of the e1b 19-kilodalton analyze the structure and function of the e1b 19,000-molecular-weight protein (19k protein) (163r) of human adenovirus type 12, mutants were produced at various positions across the 163r-coding sequence. viruses bearing mutations within the first 100 or so amino acids yielded unstable 163r-related products, induced dna degradation and enhanced cytopathic effect (cyt/deg phenotype) in kb cells, and transformed primary rodent cells at much lower efficiencies than wild-type (wt) virus. deletion ...19921532214
recombination between adenovirus type 12 dna and a hamster preinsertion sequence in a cell-free system. patch homologies and fractionation of nuclear extracts. 19921474593
alterations in the levels of expression of specific cellular genes in adenovirus-infected and -transformed cells.there is increasing evidence that changes in the transcriptional program of cellular genes in virus-transformed cells can contribute to virus transformation. it is, therefore, important to study altered expression patterns of cellular genes in adenovirus-infected and -transformed cells. we have used 40 different cellular genes or gene segments as hybridization probes to analyze the cytoplasmic rna from adenovirus type 2 (ad2)-infected kb cells, from ad5-transformed human cells (293) or from seve ...19921441738
reduced binding activity of transcription factor nf-kappa b accounts for mhc class i repression in adenovirus type 12 e 1-transformed cells.the early region 1 (e1) of human adenovirus (ad) type 12 represses the expression of major histocompatibility (mhc) class i genes in transformed primary rodent cells. in this paper we show that both nf-kappa b and kbf1 (p50 dimer) binding activity to the h2tf1 element in the class i promoter is reduced in ad12-13s-e1a-transformed cells compared to ad5e1- or ad12-12s-e1a-transformed cells. consistently, in ad12e1a-13s-transformed cells the h2tf1 element does not contribute to transcriptional acti ...19921423646
the use of beta-galactosidase fusion proteins encoding the early region 1 transforming proteins of adenovirus type 12 to examine the humoral response in tumour-bearing animals.sera from 26 rats bearing tumours induced by wild-type (wt) and mutant human adenovirus type 12 (ad12), or by cells transformed with these viruses, were analysed for antibodies against the early region 1 (e1) transforming proteins. six ad12-beta-galactosidase fusion proteins encoding different regions of the ad12 e1 proteins were constructed. the sera from the tumour-bearing animals reacted most strongly with the fusion protein encoding the n terminus of the e1a protein. tumour-bearing rats expo ...19911849978
suppression of murine leukemia virus-mediated 3y1 cell fusion by expression of mouse mhc class i.rat 3y1 fibroblasts transformed by adenovirus type 12 or its e1a gene formed syncytia by cocultivation with friend murine leukemia virus (mulv)-producing cells. on the other hand, parental 3y1 cells and those derivatives induced by other tumor viruses or chemical carcinogen showed no mulv-mediated syncytium formation [n. momozaki et al. (1990) arch. virol. 115: 123-126]. the expression of major histocompatibility complex (mhc) class i mrna and antigens was significantly reduced in these ad12- an ...19911863224
production of a low molecular weight growth inhibitory factor by adenovirus 12-transformed cells.malignant rodent cells transformed by human adenovirus 12 produce a potent cell growth inhibitory factor. the cell growth inhibitory factor inhibits the growth of and dna synthesis in normal fibroblasts in vitro. extent of the production of the cell growth inhibitory factor appears to be proportional to that of the malignancy of the transformed cells. c57at1-ab cells, an adenovirus 12-transformant of c57bl/6 mouse origin, are highly tumorigenic in the syngeneic and allogeneic mice. the cell grow ...19921417799
transcriptional and posttranscriptional regulation of class i major histocompatibility complex genes following transformation with human adenoviruses.transformation of rodent cells by human adenoviruses is a well-established model system for studying the expression, regulation, and function of class i antigens. in this report, we demonstrate that the highly oncogenic adenovirus type 12 operates at the transcriptional and posttranscriptional levels in regulating the activity of major histocompatibility complex class i genes and products in transformed cells. adenovirus type 12 suppresses the cell surface expression of class i antigens in most ...19911895404
formation in vitro of the ptp-dcmp initiation complex of human adenovirus type 12.we report the covalent addition of [32p]dcmp to a protein from group a adenovirus 12 (ad12)-infected human (kb) cells in vitro, using crude extracts. synthesis of the 60k protein-dcmp complex required a dna template containing a terminally located adenovirus replication origin; the protein-dcmp bond was alkali-labile but acid-stable. we therefore conclude that this product is the ad12 terminal protein precursor (ptp)-dcmp initiation complex for dna replication. synthesis of ad12 ptp-dcmp was spe ...19911993880
molecular cloning of cdna encoding a human heat-shock protein whose expression is induced by adenovirus type 12 e1a in hela cells.we have identified by differential plaque hybridization, human cdna clones encoding a member of a heat-shock protein family (hsp 90 alpha) in the cdna library of adenovirus type 12 e1a transfected hela cells. the complete nucleotide sequence of one of the clones (phb76-114a) was identified. the sequence of 2912 base pairs had a single reading frame with a coding potential for an 84,672-da protein. the amino acid sequence was highly homologous, but not identical, to that of the human hsp 90 alpha ...19901368637
adenovirus e1a proteins stimulate inositol phospholipid metabolism in pc12 study the influence of nuclear oncogenes on inositol phospholipid metabolism, we examined the various parameters of inositol phospholipid metabolism in pc12 cells expressing adenovirus type 12 or adenovirus type 5 e1a. although the inositol 1,4,5-trisphosphate content was increased only slightly, the diacylglycerol content was 2.4-fold higher in e1a-expressing pc12 cells. furthermore, we found that the activity of phospholipase c, one of the key enzymes in inositol phospholipid metabolism, wa ...19921326659
recombination between adenovirus type 12 dna and a hamster preinsertion sequence in a cell-free system. patch homologies and fractionation of nuclear extracts.we have previously described a cell-free recombination system derived from hamster cell nuclear extracts in which the in vitro recombination between a hamster preinsertion sequence, the cloned 1768 base-pair p7 fragment, and adenovirus type 12 (ad12) dna has been demonstrated. the nuclear extracts have now been subfractionated by gel filtration on a sephacryl s-300 column. the activity promoting cell-free recombination elutes from the sephacryl s-300 matrix with the shoulder and not the peak fra ...19921320127
differential requirement for adenovirus type 12 e1a gene products in oncogenic transformation.during the early period of infection, adenovirus type 12 e1a gene is expressed as overlapping, spliced mrnas of 12 and 13s, which encode in-frame proteins of 235 and 266 amino acid residues (235r and 266r), respectively. to define the functions of these related products in the infection of human cells and transformation of rodent cells, we created single t-to-c transitions at the second base of each mrna intron which specifically prevent splicing of the respective mrnas. mutant pm712 expresses o ...19902144595
establishment and characterization of cell lines from human adenovirus type 12-induced murine tumors producing endogenous virus particles.two cell lines designated ic-kms and d-kms were established from human adenovirus type 12-induced tumors of c3hf/ok mouse. the cell lines retained the characteristics of the original tumor i.e., production of numerous c-type and intracisternal a-type particles, integration of ad12 e1 region dna and amplification of the myc gene family. chromosomal analysis revealed chromosome aberrations in both ic-kms and d-kms cells. the modal chromosome number of ic-kms cells was 54 and that of d-kms cells wa ...19921319100
evidence for post-transcriptional selection of viral mrna in cells transformed by human adenovirus 12. 19761272415
double-stranded dna binding of adenovirus type 12 tumor antigen. 19761253982
activation of retrovirus in transgenic mice: association with development of olfactory neuroblastoma.a line of transgenic mice that express the human adenovirus type 12 e1a and e1b genes under the regulatory control of the mouse mammary tumor virus long terminal repeat was studied. mice from this line develop olfactory neuroblastomas at approximately 6 months of age. large numbers of type c retrovirus (ecotropic murine leukemia virus) particles were found in the tumor rosettes. no similar examples of virus activation were identified in tumors from other transgenic experiments. examination of sp ...19902164606
selective syncytium formation by murine leukemia virus in rat 3y1 fibroblasts transformed by adenovirus type 12 or its e1a gene.3y1 rat fibroblasts transformed by adenovirus type 12 or by its e1a gene formed syncytia when cocultivated with the friend as well as other ecotropic murine leukemia-virus-producing cells. in contrast, the parental 3y1 cells and those transformed by other tumor viruses or by a chemical carcinogen exhibited no syncytium formation.19902174230
decreased transforming ability of a temperature-sensitive mutant of human adenovirus type 12.a mutant of human adenovirus type 12, temperature-sensitive for virus replication an for the enhancement of thymidine incorporation in resting human embryonic kidney cells, is described. the mutant was also temperature-sensitive for transformation of rat cells. the results indicate that a viral gene required for the virus growth cycle is also required for transformation.19761016956
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