| no evidence for particles encapsulating rna-instructed dna polymerase and high molecular weight virus-related rna in herpesvirus induced tumours of non-human primates. | the simultaneous detection test gave no evidence for the presence of rna tumour viruses in herpesvirus induced malignant lymphomas of non-human primates. the 12 tumours tested were obtained from three different monkey species inoculated with herpesvirus saimiri or herpesvirus ateles. particles encapsulating rna-instructed dna polymerase and high mol. wt. virus-related rna were easily demonstrated in tumours of the mouse induced by type-c or type-b oncornaviruses and in human lymphoid cells infec ... | 1975 | 49397 |
| observations on the antigenic relationships between epstein-barr virus and herpesvirus saimiri. | the antigenic relationships between epstein-barr (eb) virus and herpesvirus saimiri (hvs) have been investigated in comparative immunofluorescence, microimmunodiffusion and serum neutralization tests. no similarity was detected between the structural antigens of the two herpesviruses but the results of microimmunodiffusion tests showed that they shared a non-structural, virus-determined antigen. the implications of this finding are discussed in relation to the importance of hvs and its monkey ly ... | 1977 | 70507 |
| spontaneous lymphoma associated with herpesvirus saimiri in owl monkeys. | two cases of lymphoma and one case of lymphoproliferative disease were found in a group of 7 owl monkeys imported into our colony as a single group. herpesvirus saimiri (hvs) was isolated from the tumor cells of 1 lymphoma by cocultivation and from kidney cell cultures from the monkey with lymphoproliferative disease. antibody to hvs was found in serum samples from 2 monkeys positive for hvs but not in the sera from the 4 clinically normal monkeys. antibody to epstein-barr virus-infected cells w ... | 1975 | 163336 |
| infection of capuchin monkeys (cebus albifrons) with herpesvirus saimiri. | herpesvirus saimiri (hvs) induced persistent, clinically inapparent infections of long-term duration in capuchin monkeys (cebus albifrons). the infections were characterized by development of antibody to hvs-associated antigens and recovery of low levels of virus-genome-carrying lymphocytes in the peripheral blood. peripheral lymphocyte counts remained in low-normal to normal ranges and no physical signs of lymphoma were evident. prednisolone treatment caused immunosuppression in one monkey; thi ... | 1975 | 164564 |
| depression in lymphocyte response to general mitogens by owl monkeys infected with herpesvirus saimiri. | the effect of herpesvirus saimiri (hvs) infection on the response of owl monkey lymphocytes to general mitogens was examined during the development of neoplastic disease. the reactivity of the lymphocytes was then correlated with the clinical condition of the infected monkeys and the content of virus rescued from the peripheral blood lymphocytes (pbl). eight monkeys developed lymphoma which, in six monkeys, was accompanied by lymphocytic leukemia. all animals that died of hvs-induced neoplasia c ... | 1975 | 164565 |
| effect of bacillus calmette-guérin immunization in marmosets infected experimentally with herpesvirus saimiri. | eight white-lipped marmosets immunized with bcg and 3 sham-immunized marmosets were studied after inoculation with herpesvirus saimiri (hvs). bcg immunization had no significant influence on the incidence of infection by hvs, incidence of fatal malignant lymphoma, time of leukemia onset, development or titer of hvs antibodies, or average survival time. one bcg-immunized, hvs-infected marmoset failed to develop malignant lymphoma, whereas the remaining 10 hvs-infected marmosets died of malignant ... | 1975 | 164566 |
| replication of herpesvirus saimiri in cultured lymphocytes of infected owl monkeys (aotus trivirgatus). an electron microscopic and immunofluorescent study. | the lymphocytes of five owl monkeys infected with herpesvirus saimiri (hvs) and three control monkeys were studied. lymphocytes were separated on ficoll-hypaque gradients, incubated in suspension cultures, and prepared for electron microscopic and immunofluorescent study at 24, 48, and 72 hours after the beginning of culture (ac). buffy coats of whole blood immediately after bleeding were also prepared for study. at the time of the study, four of the five infected monkeys had died of malignant l ... | 1975 | 165331 |
| clinicopathologic characterization of herpesvirus saimiri malignant lymphoma in new zealand white rabbits. | twenty-two of 39 rabbits inoculated with herpesvirus saimiri developed malignant lymphoma and either died or were killed between 17 and 165 days after inoculation. no clinical signs were present in animals developing the disease before 46 days, but all other rabbits had a severe conjunctivitis, nasal discharge, and dyspnea resulting from a lymphocytic invasion of the ocular and nasal tissues. four rabbits developed terminal leukemia. pathologically, the disease resembled h. saimiri malignant lym ... | 1975 | 166191 |
| augmentation of lymphocyte cytotoxicity by antibody to herpesvirus saimiri associated antigens. | sera from owl monkeys infected with herpesvirus saimiri (hvs) mediated antibody-dependent lymphocyte cytotoxicity (adlc) against virus-infected owl monkey kidney cells. peripheral blood lymphocytes from rhesus monkeys served as effector cells in this cytotoxic assay. adlc titers increased along with membrane immunofluorescence (mf) titers but among some sera, the adlc titers were much higher than expected from the mf titers, suggesting that multiple serum factors were involved in mediating adlc ... | 1975 | 169525 |
| spontaneous herpesvirus saimiri lymphoma in owl monkeys. | three examples of spontaneous malignant lymphoma were observed in owl monkeys 23, 81, and 183 days after arrival in our laboratories. the pathological features of the disease were analogous to experimentally induced herpesvirus saimiri lymphoma. h. saimiri was recovered from 2 animals (it was not attempted from one case) and one isolate was shown to reproduce characteristic h. saimiri malignant lymphoma. each monkey originated in peru in contrast to our usual source of owl monkeys which originat ... | 1975 | 169813 |
| experiments to vaccinate marmoset monkeys against malignant lymphoma. | humoral antibodies can be induced in cotton topped (ct) marmosets with killed herpesvirus saimiri (hvs) vaccines. the serum antibodies delayed, but did not prevent, malignant lymphoma in actively and passively immunized monkeys after inoculation with 10(3.8)tcid50 of cell-free hvs. experiments are in progress to determine whether the vaccines are able to protect against smaller challenge dosages of hvs. the immunized monkeys were not resistant against transplantation of tumor cells. infection wi ... | 1975 | 169814 |
| comparisons of surface markers on herpesvirus-associated lymphoid cells of nonhuman primates and established human lymphoid cell lines. | herpesvirus saimiri (hvs)-owl monkey lymphoid cells were found to have high levels of surface receptor for sheep erythrocytes and erythrocytes of 3 other species. these hvs-lymphoid cells lacked a receptor for modified complement. lymphoid cells of one hvs-owl monkey line showed evidence for the presence of surface immunofluorescent staining with anti-kappa chain serum. cells of an established hvs-marmoset lymphoid line had similar surface markers. of 4 established human lymphoid cell lines, all ... | 1975 | 169815 |
| immunological control of virus-induced tumors in primates. | cells infected by oncogenic viruses may transform, may develop a latent carrier state, or may be destroyed but understanding of the control of the results of infection is incomplete. even if cells transform, ultimate development of a tumor may be immunologically controlled. for example, cells of some marmoset species transform after infection with rna tumor viruses, and animals react to the transformed cells with cell-mediated and humoral immune responses. both virus specific and cross-reacting ... | 1975 | 169832 |
| nonhuman primate models for lymphoma, leukemia, and other neoplasms. | herpesvirus saimiri (hvs) is an oncogenic virus for a variety of nonhuman primates. hvs does not produce overt disease upon inoculation in the natural host (squirrel monkey) but consistently induces neoplasms including lymphomas and lymphocytic leukemias in 4 other species of monkeys. various drugs inhibit replication of hvs in vitro including cytosine arabinoside and adenine arabinoside. in addition, the lymphoma and leukemia induced in owl monkeys responds to vincristine and prednisolone, cycl ... | 1975 | 169836 |
| response to primary infection with herpesvirus saimiri in immunosuppressed juvenile and newborn squirrel monkeys. | immunosuppression of juvenile squirrel monkeys with combined azathioprine, prednisolone, and antilymphocyte globulin resulted in decreased antibody responses to viral antigens after primary infection with herpesvirus saimiri (hvs). the virus was repeatedly isolated from the oropharynx of immunosuppressed monkeys but not from untreated infected controls. thus immune factors are important in inhibiting shedding of hvs from the oropharynx. hvs could be isolated from the peripheral blood lymphocytes ... | 1975 | 170204 |
| the effect of an immunosuppressive drug (azathioprine) on the latent infection of marmoset monkeys (callithrix jacchus) with the oncogenic herpesvirus saimiri. | callithrix jacchus (cj) marmoset monkeys can be latently infected with herpesvirus saimiri (hvs). in order to determine whether this resistance to the oncogenic potential of hvs could be due to the immune surveillance, azathioprine, a known immunosuppressive drug, was given to 7 latently infected cj marmosets. the animals died within 147 days probably from side effect caused by azathioprine, but no animal developed a tumor. | 1975 | 170499 |
| inhibition of the mitogenic response of normal peripheral lymphocytes by extracts or supernatant fluids of a herpesvirus saimiri lymphoid tumor cell line. | a herpesvirus saimiri-infected marmoset lymphoid cell line (mlc-1) was examined for the presence of soluble factors which might affect lymphocyte functions and, therefore, relate to the pathogenesis of lymphoma in vivo. mlc-1 cells, cell extracts, and culture fluids were shown to reduce the spontaneous deoxyribonucleic acid (dna) synthesis of normal peripheral blood lymphocytes and to completely inhibit their response to phytohemagglutinin (pha). suppression of pha response was demonstrated agai ... | 1975 | 172449 |
| experimental horizontal transmission of herpesvirus saimiri from squirrel monkeys to an owl monkey. | herpesvirus saimiri was naturally transmitted from squirrel monkeys excreting the virus to one of two owl monkeys housed in the same cage. the owl monkey became infected approximately three months after contact was initiated. h. saimiri was consistently isolated from the peripheral lymphocytes until this animal died eight months later. during this period the owl monkey developed specific antibody to h. saimiri to a maximal neutralization index of 5.5 logs. the other monkey remained uninfected fo ... | 1975 | 172563 |
| induction and in vitro demonstration of cellular immunity to dna and rna viruses in guinea-pigs. | guinea-pigs were immunized with different cells infected with vaccinia virus, herpes simplex virus type 1, herpesvirus saimiri, and the virus of vesicular stomatitis. development of cellular immunity against these viruses was observed with transformation of blood and spleen lymphocytes and with the migration inhibition test using peritoneal exudate cells. cellular immunity against vaccinia virus was first seen 6 days after the inoculation of cell-bound vaccinia virus by lymphocyte transformation ... | 1975 | 173485 |
| attenuation of herpesvirus saimiri for marmosets after successive passage in cell culture at 39 degrees c. | a variant of herpesvirus saimiri (hvs) stably attenuated for marmosets was isolated after serial passage of wild-type hvs in cell culture at 39 degrees c. marmosets previously inoculated with attenuated virus experienced a significant delay in the development of lymphoma when challenged with wild-type hvs. | 1975 | 173864 |
| purification of herpesvirus saimiri and properties of the viral dna. | conditions for growth, concentration, and purification of herpesvirus saimiri were determined. optimal yields of infectious herpesvirus saimiri (hvs) were obtained from infected owl monkey kidney (omk) cells grown at 32.5 degrees c in medium containing 10 per cent fetal calf serum. forth-five percent of the initial infectious hvs was recovered after an 18-fold concentration using 8 per cent polyethylene glycol 6000 in the presence of 0.5 m nacl. polyethylene glycol concentrated hvs was purified ... | 1975 | 174525 |
| immune response of monkeys to lymphotrophic herpesvirus antigens. | herpesvirus saimiri induces leukemia and/or malignant lymphoma when inoculated into different species of nonhuman primates including marmosets and owl monkeys. no malignant disease, however, has been recognized in the natural host for this virus, the squirrel monkey, although a high percentage of these monkeys are chronically infected with h. saimiri. furthermore, one species of marmosets, as well as capuchin and some owl monkeys, fail to develop lymphoma following experimental virus infection b ... | 1976 | 175927 |
| preventive vaccination against herpesvirus saimiri-induced neoplasia. | in this paper we discuss the use of herpesvirus saimiri as a model for the development of vaccines against herpesvirus-induced neoplasia in primates. attempts at protection against the oncogenicity of h. saimiri have centered on the inactivation of virus by heat and formalin, the production of temperature-sensitive h. saimiri mutants, and the attenuation of the virus. each of these approaches has provided information of use in the development of vaccines that may possibly be used in man. | 1976 | 175928 |
| vaccination of nonhuman primates with killed oncogenic herpesviruses. | killed herpesvirus cancer vaccines were prepared by inactivation of oncogenic herpesviruses (herpesvirus saimiri and herpesvirus ateles) with heat and formaldehyde. the killed vaccines, which are not free of viral nucleic acid, were safe in 121 vaccinated monkeys of 4 different species. some of these monkeys have now been under observation for 2 years. the vaccines induced high titers of specific humoral antibodies in all vaccinated monkeys. the killed vaccines proved to be efficient against the ... | 1976 | 175929 |
| experimental infection of squirrel and marmoset monkeys with attenuated herpesvirus saimiri. | herpesvirus saimiri (hvs) was propagated in vero cells for 3 passages at 39 degrees and cloned 3 times at 34 degrees. this virus was inoculated into cotton-topped marmoset and squirrel monkeys; all inoculated monkeys became infected as hvs was reisolated after their circulating lymphocytes were cultured with vero cells and measurable levels of antiviral antibodies developed that were measured by immunofluorescence and/or neutralization tests. none of the inoculated monkeys developed any signs of ... | 1976 | 175930 |
| pilot studies with human interferon in herpesvirus saimiri-induced lymphoma in owl monkeys. | the nature of herpesvirus saimiri-induced disease in owl monkeys is described with emphasis on those biological parameters useful in monitoring the disease. these parameters are lymphocyte response to general mitogens, lymphocyte-infective centers, and antibody to virus-associated early antigen. human interferon was used in treating owl monkeys with virus-induced leukemia. in 2 animals evidence was obtained that suggested a positive antileukemic effect. | 1976 | 175932 |
| electron microscopic study of the development of herpesvirus saimiri. | | 1976 | 176797 |
| evidence for suppressor cell activity associated with induction of herpesvirus saimiri-induced lymphoma. | peripheral blood lymphocytes (pbl) from herpesvirus saimiri (hvs) infected owl monkeys lose their ability to respond to pha during the development of lymphoma. in this study, five hvs-infected owl monkeys were examined for their ability to respond to pha and to confer this loss of pha reactivity to normal lymphocytes. four of the monkeys developed hvs-induced disease and lost their ability to respond to pha. although less affected, reduced responses were also found with pwm. the animals which de ... | 1975 | 178474 |
| structure of herpesvirus saimiri genomes: arrangement of heavy and light sequences in the m genome. | herpesvirus saimiri contains two species of dna molecules. (i) the m genome is composed of 70% light (l) dna (36% cytosine plus guanine; density in cscl, 1.695 g/ml), which consists of unique sequences, and 30% heavy (h) dna (71% cytosine plus guanine; density, 1.729 g/ml). (ii) the h genome contains heavy sequences exclusively. h sequences in m and h genomes cross-hybridize completely and are cleaved identically by restriction endonuclease r-sma i into four classes of fragments with molecular w ... | 1976 | 181593 |
| the role of herpesvirus saimiri genomes in oncogenic transformation of primate cells. | | 1975 | 183689 |
| correspondence between t cell suppression and adlc titers during herpesvirus saimiri (hvs) infection in owl monkeys. | | 1975 | 183696 |
| lymphocyte responsiveness in squirrel, cebus and marmoset monkeys infected with herpesvirus saimiri. | | 1975 | 183704 |
| antilymphocytic factor derived from a herpesvirus saimiri lymphoid tumor cell line. | | 1975 | 183705 |
| reactivation of squirrel monkey heart isolate (herpesvirus saimiri strain) from latently infected human cell cultures and induction of malignant lymphoma in marmoset monkeys. | | 1975 | 183706 |
| morphological observations on the replication of herpesvirus saimiri in monkey kidney cell cultures. | owl and african green monkey kidney cell cultures have been infected with 1 p.f.u./cell of herpesvirus saimiri and sample cultures have been taken for examination by electron microscopy at 3 to 6 hourly intervals over a period of 7 days; the experiments were repeated several times. the peculiarly slow replication cycle of herpesvirus saimiri has enabled distinct cytoplasmic and nuclear phases in virus maturation to be clearly distinguished; the overall fine structural features were similar in bo ... | 1976 | 184242 |
| antibody responses to membrane antigens in monkeys infected with herpesvirus saimiri. | the antibody response to herpesvirus saimiri (hsv)-induced membrane antigens (ma) was followed in hsv-infected owl monkeys using the membrane immunofluorescence (mf) and antibody-dependent lymphocyte cytotoxicity (adlc) assays. these responses were correlated with the loss of t-cell responsiveness to general mitogens. antibody titers to ma as determined by adlc but not mf increased to remarkably high titers in those monkeys that developed malignant disease following virus infection, while remain ... | 1976 | 186415 |
| chronic herpesvirus saimiri infection in an owl monkey. | an adult owl monkey (aotus tricirgatus) used for immunologic studies of herpesvirus saimiri (hvs) developed early, late, membrane, and neutralizing antibodies to hvs approximately 3 weeks after the beginning of the experiment. hvs was isolated by the cocultivation of peripheral blood for over 1 year. no clinical, gross, or histopathologic findings of malignancy were exhibited by the animal. the hvs isolate from the animal was indistinguishable biologically and serologically from the original hvs ... | 1976 | 186615 |
| herpesviruses and cancer in man and subhuman primates. | because there is strong evidence for the involvement of epstein-barr virus in the etiology of burkitt's lymphoma and nasopharyngeal carcinoma, we have discussed the relationship of epstein-barr virus to these two diseases in the context of geographic distribution, pathology, epidemiology, genetics, immunovirology, and biochemistry. we have also discussed the relationship of epstein-barr virus to other diseases, both malignant and non-malignant. although the etiologic relationship of herpes simpl ... | 1976 | 187259 |
| inhibition of herpesvirus saimiri replication by phosphonoacetic acid, benzo(a)pyrene, and methylcholanthrene. | the present investigations were undertaken to determine the possible effects of two carcinogenic polycyclic aromatic hydrocarbons, benzo(a)pyrene and 3-methylcholanthrene on herpesvirus saimiri replication. the results from these experiments were compared with the effects of phosphonoacetic acid on the virus replication cycle. phosphonoacetic acid inhibited the synthesis of virus-induced intracellular late antigens, membrane antigens and infectious virus but not the synthesis of the early antige ... | 1977 | 187336 |
| herpesvirus saimiri-induced malignant lymphoma in rabbits. | of 9 new zealand white rabbits inoculated at multiple sc and im sites with a single dose of herpesvirus saimiri (hvs), 2 developed malignant lymphomas 40-50 days post inoculation. at least 1 animal developed a terminal leukemic phase of the disease. hvs was isolated from the oral and conjunctival swabs and blood and tissue lymphocytes, but not from monolayer cell cultures derived from kidney or lung tissues of the diseased animals. the inoculated rabbits developed low titers of neutralizing anti ... | 1976 | 187760 |
| oncornavirus particles in lymphoid cultures from a howler monkey with herpesvirus saimiri-induced disease. | budding and extracellular oncornavirus particles were observed in cells of lymphoid cultures derived from the spleen, lymph node, and blood of a howler monkey (alouatta caraya) that developed a malignant lymphoproliferative disease after infection with herpesvirus saimiri. the various possible sources of origin of these particles are discussed. | 1976 | 187783 |
| mononuclear cell fraction carrying herpesvirus saimiri in persistently infected squirrel monkeys. | circulating lymphocytes from squirrel monkeys persistently infected with herpesvirus saimiri (hvs) were separated into b- and t-lymphocyte fractions by a rosette-enrichment technique. hvs was isolated only from lymphocyte fractions forming rosettes or from unseparated lymphocytes; this indicated that t-lymphocytes were the target cells for hvs in the natural host, squirrel monkeys. | 1976 | 187784 |
| sequential immunofluorescence and infectivity studies on the replication of herpesvirus saimiri in owl monkey kidney cells. | methods are described for the preparation and authentication of a highly specific antiserum against herpesvirus saimiri (hvs) capsid antigens. the antiserum was used in immunofluorescence tests to follow the development of capsid antigens in hvs-infected owl monkey kidney cells throughout the virus replication cycle in parallel with sequential titrations of virus infectivity in both cells and medium. fluorescence was detected as a round or oval, bright green area of staining at the centre of the ... | 1977 | 188981 |
| absence of horizontal transmission of herpesvirus saimiri between experimentally infected and noninfected owl monkeys. | we did not detect cell-free herpesviurs saimiri (hvs) in the oropharyngeal secretions of owl monkeys with leukemia or lymphoma induced by this virus. these animals failed to transmit either virus or disease to their uninoculated cage-mates or room-mates. comparison of oropharyngeal secretions of hvs from owl monkeys and squirrel monkeys may provide insight as to how human herpesviruses are maintained in the oropharynx. | 1976 | 189906 |
| studies of the dna of herpesvirus saimiri. | | 1975 | 190117 |
| partial purification and biochemical characterization of herpesvirus saimiri. | hvs propagated in vero cells was labelled with 3h-leucine and purified by isopycnic flotation in sucrose. electron microscopic examination revealed both complete and incomplete hvs. no significant contamination with cellular debris was noted. polyacrylamide gel electrophoresis analysis of solubilized virus revealed at least 12 proteins varying in molecular weight from 8 000 to 200 000 daltons. | 1975 | 190128 |
| some biological properties of herpesvirus saimiri from chronically infected monolayer and suspension cultures. | hvs-mest cells, which are adherent, produced more infectious hvs at 37 degress c than at 33 degrees c. this was paralleled by the appearance of ea and la in rounded cells and cf antigen in the cell cultures. in contrast, mlc-1 cells, which grow in suspension, produced hardly any infectious virus, but did produce more hvs s antigen than did the hvs-mest cells. production of s antigen in mlc-1 cells was augmented by treatment of the cells with budr. hvs-mest cells could be superinfected with hvs, ... | 1975 | 190156 |
| the owl monkey (aotus trivirgatus) as an animal model for viral diseases and oncologic studies. | the owl monkey (aotus trivirgatus) has been shown to be an excellent model for studies of oncogenic and non-oncogenic viruses. studies at this institution have been primarily concerned with herpesvirus saimiri, the epstein-barr virus, h tamarinus, and h simplex. these studies have shown that h saimiri is oncogenic when inoculated into primates, that the malignancy induced by h saimiri can be naturally transmitted from the squirrel monkey to the owl monkey, that in vitro pathogenicity of h saimir ... | 1976 | 190472 |
| studies of cultured lymphocytes of the owl monkey (aotus trivirgatus) infected with herpesvirus saimiri. | the lymphocytes of five owl monkeys (aotus trivirgatus) infected with herpesvirus saimiri and three control monkeys were studied. lymphocytes were separated on ficoll-hypaque gradients, incubated in suspension cultures, and prepared for electron microscopic and immunofluorescent study at 24, 48, and 72 hours after the beginning of culture. buffy coats of whole blood obtained immediately after bleeding were also prepared for study. at the time of the study, four of the five infected monkeys had d ... | 1976 | 190473 |
| ultrastructural and immunofluorescent studies of the replication of herpesvirus saimiri in cultured lymphocytes of infected owl monkeys. | the lymphocytes of five owl monkeys infected with herpesvirus saimiri (hvs) and of three control owl monkeys were studied by electron microscopic (em) and immunofluorescent (if) techniques. buffy coats of whole blood immediately after bleeding were also prepared for study. at the time of the study, two of the five infected monkeys were leukaemic; within 50 days after the study, four of the five had died with malignant lymphoma and lymphocytic leukaemia. hvs virions were demonstrated by em and hv ... | 1975 | 191352 |
| induction of herpesvirus saimiri lymphoma in new zealand white rabbits inoculated intravenously. | | 1975 | 191364 |
| induction of serum antibodies in non-human primates with a killed oncogenic herpesvirus (herpesvirus saimiri). | | 1975 | 191378 |
| in vitro attenuation of herpesvirus saimiri by serial passage in dog fetal lung continuous cultures. | | 1975 | 191379 |
| the presence of herpesvirus saimiri genomes in virus-transformed cells. | herpesvirus saimiri (h. salmiri) -transformed cells contained both types of viral dna, unique l-dna and highly repetetive h-dna. dna from spleen and lymph-node autopsies of two tumor-bearing marmoset monkeys contained 0.14-0.75% viral l-dna -and 0.115-1.08% h-dna. this amount of h-dna would be equivalent to the presence of 14-130 m-genomes per diploid tumor tissue cell. six virus-transformed lymphoid cell lines, two of them virus-producing, contained 0.69-2.27% h-dna and more than 0.72-1.95% l-d ... | 1977 | 191414 |
| in vitro suppression of herpesvirus saimiri replication by phosphonoacetic acid. | | 1977 | 191845 |
| lamella-particle complexes in nuclei of owl monkey kidney cells infected with herpesvirus saimiri. | a complex consisting of ribosome-like particles and a striated lamella occurring in stacked, tubular, and twisted ribbon-like configurations was observed in the nuclei of confluent monolayer cultures of primary owl monkey kidney cells infected with herpesvirus saimiri. they were similar to the cytoplasmic cylindroid structures seen in some human leukemias and in the lymphoma of the northern pike. | 1977 | 192900 |
| immune surveillance--a powerful mechanism with a limited range. | there is excellent evidence for the belief that immune surveillance mechanisms prevent the outgrowth of potentially neoplastic cells induced by horizontally transmitted, ubiquitous, potentially oncogenic viruses, indigenous to natural populations. polyoma virus in mice, marek's disease in the chicken, herpesvirus saimiri in the squirrel monkey, and the epstein-barr virus in man are examples. there is much less evidence for immune surveillance against chemically induced tumors. it is argued that ... | 1976 | 193016 |
| herpesvirus saimiri-induced lymphoproliferative disease in howler monkeys. | four of 5 howler monkeys (alouatta caraya) experimentally infected with herpesvirus saimiri (hvs) developed a rapidly fatal malignant lymphoma accompanied by peripheral t-cell lymphocytosis. hvs was isolated from fresh and tissue cultured blood and tissue lymphocytes and from cell cultures derived from nonlymphoid organs. humoral antibodies against hvs-induced antigens were detected in the sera of the animals. the in vitro response of the peripheral blood lymphocytes to mitogenic stimulants was ... | 1977 | 195067 |
| episomal viral dna in a herpesvirus saimiri-transformed lymphoid cell line. | the lymphoid cell line #1670 has been derived from the infiltrated spleen of a tumor-bearing marmoset monkey infected with herpesvirus saimiri. the cells contain both types of h. saimiri dna, unique light (l-) dna (36% cytosine plus guanine) and repetitive heavy (h-) dna (71% cytosine plus guanine), without producing infectious virus. viral dna was found to persist in these cells as nonintegrated circular dna molecules. closed circular superhelical viral dna molecules were isolated by three subs ... | 1977 | 195090 |
| electron microscopic study of herpesvirus saimiri. | | 1977 | 195393 |
| susceptibility of common marmosets (callithrix jacchus) to oncogenic and attenuated strains of herpesvirus saimiri. | adult common marmosets, inoculated with either of 2 oncogenic herpesvirus saimiri (hvs) strains, developed fatal lymphoproliferative disease within 23-25 days post inoculation (pi). the disease was identical to hvs-induced lymphoma in cotton-topped and white-lipped marmosets. common marmosets inoculated with an attenuated hvs strain developed persistent infection; virus has been recovered from cocultivated lymphocytes of these animals for more than 384 days pi. | 1977 | 198565 |
| herpesvirus ateles dna and its homology with herpesvirus saimiri nucleic acid. | analysis of the structural organization of herpesvirus ateles dna shows that two types of viral dna molecules are encapsidated in virions: (i) m-genomes, which contain 74% light sequences (l-dna, 38% guanine plus cytosine) and 26% highly repetitive heavy sequences (h-dna, 75% guanine plus cytosine), and (ii) defective h-genomes, which consist exclusively of repetitive h-dna. the structure of m-genomes from h. ateles consists of an l-dna region of about 70 x 10(6) daltons inserted between h-dna t ... | 1978 | 202747 |
| solubilization and characterization of herpesvirus saimiri-induced membrane antigens. | treatment of herpesvirus saimiri (hvs)-infected owl monkey cells by limited papain digestion removed the hvs-induced membrane antigen (ma) as determined by membrane immunofluorescence and antibody-dependent lymphocyte cytotoxicity (adlc). soluble antigenically active hvsma was detected by inhibition of adlc and by the decreased binding of 125i-labeled staphylococcus protein a to hvs-infected cells after absorption of an anti-ma-positive serum with papain extracts. approximately 38% of the inhibi ... | 1978 | 205674 |
| experimental infection of callithrix jacchus marmosets with herpesvirus ateles, herpesvirus saimiri, and epstein barr virus. | we inoculated common marmosets (callithrix jacchus) with herpesvirus ateles (hva), herpesvirus saimiri (hvs), and epstein-barr virus (ebv). hva-induced tumors contained several cell types, including giant cells reminiscent of the sternberg-reed cells observed in human hodgkin's disease. hvs and ebv did not induce tumors, although hvs was present in lymphocytes and elicited a strong antibody response. ebv elicited only a variable antibody response. we feel that more common marmosets should be use ... | 1978 | 208678 |
| augmentation of the in vitro mitogenic response of owl monkey peripheral blood lymphocytes by levamisole and loss of this effect with the development of herpesvirus saimiri-induced lymphoma. | levamisole (lms) has been shown to be capable of enhancing the proliferative response of normal owl monkey peripheral blood lymphocytes (pbl) to pha, and, to a lesser degree, of increasing the level of spontaneous dna synthesis. with the development of herpesvirus saimiri-induced lymphoma, these stimulatory responses were lost. lms was not capable of stimulating tumour cells to normal functions, or of reversing the disease-induced suppressed functions on normal cells. | 1978 | 213219 |
| episomal viral dna in herpesvirus saimiri-transformed lymphoid cell lines. | structural analysis of episomal viral genomes from two herpesvirus saimiri (hvs)-transformed tumour cell lines (no. 1670 and 70n2) showed that both types of episomes have a higher molecular weight than linear virion dna. the arrangement of unique (l) and repetitive (h) dna in no. 1670 episomes was studied by partial denaturation mapping. part of the l-sequences present in linear virion dna was found to be missing, part was found to be duplicated in the episomes. the episomal l-dna regions were c ... | 1978 | 221324 |
| potential for immunization against herpesvirus infections with plasma membrane vesicles. | virus-free, membrane antigen (ma)-positive plasma membrane vesicles produced from herpesvirus saimiri-infected owl monkey cells were used as immunogens in cotton-top marmosets. neutralizing antibodies as well as antibodies to ma and hvs-induced la were induced following immunization of marmosets with these vesicles. preliminary findings demonstrated that immunized marmosets were significantly less susceptible to tumour induction by hvs than control animals. | 1978 | 221369 |
| squirrel monkey retrovirus and herpesvirus saimiri: observation in the same cell following isolation. | electron microscopic examination of mink lung cells previously cultured with a squirrel monkey (saimiri sciureus) throat swab suspension revealed the presence of squirrel monkey retrovirus (smrv) and herpesvirus saimiri (hvs) coexisting within the same cells in culture. hvs was identified by serum neutralization, and the retrovirus isolate was identified as smrv by a morphologic examination, microimmunodiffusion analysis, and demonstration of an mg2+ preference for the rna-directed dna polymeras ... | 1979 | 225504 |
| methylation of herpesvirus saimiri dna in lymphoid tumor cell lines. | several continuous lymphoid cell lines have been established from tumors induced by herpesvirus saimiri. at least a portion of the viral dna in the marmoset lymphoid cell line 1670, which does not produce detectable virus, is present as covalently closed circular episomal dna. the use of restriction endonuclease digestion, transfer to nitrocellulose filters, and hybridization of the virus-specific dna has produced strong evidence that viral dna sequences present in total 1670 cell dna and in iso ... | 1979 | 226983 |
| isolation and partial characterization of an antibody enhancing factor from leukaemic owl monkey cell cultures. | herpesvirus saimiri inoculated into owl monkeys (aotus trivirgatus) causes leukaemia and lymphoma. peripheral lymphocytes from leukaemic monkeys grown in culture are predominantly t lymphocytes. the supernatants from these cultures contain a factor which enhances the antibody response of murine b cells to sheep red blood cells (srbc). the factor has been partially characterized by ammonium sulphate precipitation, deae-chromatography, gel filtration over sephadex g-150 and disc-gel electrophores ... | 1978 | 342395 |
| isolation of virus-free herpesvirus saimiri antigen-positive plasma membrane vesicles. | experiments were undertaken to determine whether virus-free, antigen-positive plasma membrane vesicles could be isolated from owl monkey kidney cells infected with herpesvirus saimiri. the results demonstrate that vesicles can be produced by using a vesiculation fluid containing 25 mm formaldehyde/2 mm dithiothreitol. electron microscopy revealed that these vesicles were free of detectable virus particles. vesicles prepared from the infected cells contained virus-induced membrane antigens as sho ... | 1977 | 407579 |
| repetitive sequences in complete and defective genomes of herpesvirus saimiri. | two types of herpesvirus saimiri genomes can be isolated from purified virions: (i) the m genome is a double-stranded, liniear dna molecule with a mean contour length corresponding to 89 times 10-6 daltons. the m genome contains about 70% of unique sequences (light dna, 36% guanine plus cytosine) and 30% reiterated sequences (heavy dna, 71% guanine plus cytosine). (ii) the h genome is composed of heavy dna only and is more heterogeneous in size. the sequences in the h genome are up to 40-fold re ... | 1975 | 803569 |
| preferential inhibition of herpes-group viruses by phosphonoacetic acid: effect on virus dna synthesis and virus-induced dna polymerase activity. | | 1976 | 960726 |
| herpesvirus saimiri encodes homologues of g protein-coupled receptors and cyclins. | herpesvirus saimiri (hvs) is a t-lymphotropic gammaherpesvirus which establishes asymptomatic infections in its natural host the squirrel monkey (saimiri sciureus), but which causes fatal lymphoproliferative diseases in other new world primates. sequencing studies show hvs is closely related to the human b-lymphotropic gammaherpesvirus epstein-barr virus (ebv). however, despite the general colinearity between the genomes of hvs and ebv, hvs contains genes not found in ebv or in the genomes of an ... | 1992 | 1309943 |
| herpesvirus saimiri oncogene stp-c488 encodes a phosphoprotein. | the stp-c488 open reading frame of herpesvirus saimiri encodes an oncoprotein that has transforming and tumor-inducing activities independent of the rest of the herpesvirus genome. stp-c488 protein has an unusual, membrane-associated, fibrous structure and is located primarily in perinuclear compartments. we now report that stp-c488 is phosphorylated in vivo. the phosphorylated form, which accounted for about 15% of stp-c488 in transformed cells, migrated slightly more slowly through sodium dode ... | 1992 | 1310780 |
| viral small nuclear ribonucleoproteins bind a protein implicated in messenger rna destabilization. | herpesvirus saimiri (hvs) is one of several primate viruses that carry genes for small rnas. the five h. saimiri-encoded u rnas (hsurs) are the most abundant viral transcripts expressed in transformed marmoset t lymphocytes. they assemble with host proteins common to spliceosomal small nuclear ribonucleoproteins (snrnps). hsurs 1, 2, and 5 exhibit sequences at their 5' ends identical to the auuua motif, which targets a number of protooncogene, cytokine, and lymphokine mrnas for rapid degradation ... | 1992 | 1311093 |
| stable growth transformation of human t lymphocytes by herpesvirus saimiri. | herpesvirus saimiri induces t-cell lymphomas in various species of new world monkeys and in rabbits, and it is able to immortalize monkey t lymphocytes in vitro. sequences responsible for these effects have been localized to a region of the genome that varies significantly among the virus subgroups a, b, and c. we now report that infection of human blood lymphocytes and thymocytes with strains of subgroup c, in contrast to viruses of the other subgroups, yields continuously proliferating t-cell ... | 1992 | 1313581 |
| analysis of nucleotide sequence of the rightmost 43 kbp of herpesvirus saimiri (hvs) l-dna: general conservation of genetic organization between hvs and epstein-barr virus. | we present an analysis of 43,658 bp of contiguous nucleotide sequence comprising the right terminal region (conventional orientation) of the unique protein-coding component (l-dna) of the herpesvirus saimiri (hvs) genome. within this region lie the genes encoding the 160-kda virion protein, which is homologous to the 140-kda membrane antigen of epstein-barr virus (ebv), thymidylate synthase (ts), and the immediate-early (ie) 52-kda protein which is homologous to the ebv bmlf1 product. the 160-kd ... | 1992 | 1314457 |
| nucleotide sequence of hsur 6 and hsur 7, two small rnas of herpesvirus saimiri. | | 1992 | 1315960 |
| new member of the multigene family of complement control proteins in herpesvirus saimiri. | a number of glycoproteins are regulators of the complement cascade and prevent damage to cells by inappropriate activation of complement. in humans, all of them are encoded by a multigene family on chromosome i and share a characteristic structural feature, the short consensus repeats of about 61 amino acids with a constant framework of cysteine, proline, and tryptophan. we found the gene for glycoproteins of analogous structure in herpesvirus saimiri, a t-lymphotropic tumor virus of new world p ... | 1992 | 1316492 |
| primary structure of the herpesvirus saimiri genome. | this report describes the complete nucleotide sequence of the genome of herpesvirus saimiri, the prototype of gammaherpesvirus subgroup 2 (rhadinoviruses). the unique low-g + c-content dna region has 112,930 bp with an average base composition of 34.5% g + c and is flanked by about 35 noncoding high-g + c-content dna repeats of 1,444 bp (70.8% g + c) in tandem orientation. we identified 76 major open reading frames and a set of seven u-rna genes for a total of 83 potential genes. the genes are c ... | 1992 | 1321287 |
| the epstein-barr virus r transactivator (rta) contains a complex, potent activation domain with properties different from those of vp16. | rta, encoded by epstein-barr virus (ebv), is a potent activator of transcription via enhancer sequences located upstream of several viral genes. to identify the domains of rta that facilitate transcription by interacting with cellular transcription factors, different segments of rta were linked to the dna binding domain of yeast transactivator gal4 (residues 1 to 147). these gal4-rta fusion proteins were tested in transfected cells for their ability to activate the adeno e1b promoter with an ups ... | 1992 | 1323708 |
| genetic relationships between bovine herpesvirus 4 and the gammaherpesviruses epstein-barr virus and herpesvirus saimiri. | the overall arrangement of genes in the unique central part of the bovine herpesvirus type 4 (bhv-4) genome has been deduced by analysis of short dna sequences. twenty-three genes conserved in at least one of the completely sequenced herpesviruses have been identified and localized. all of these genes encoded amino acid sequences with higher similarity to proteins of the gammaherpesviruses epstein-barr virus (ebv) and herpesvirus saimiri (hvs) than to the homologous products of the alphaherpesvi ... | 1992 | 1325698 |
| molecular biology of bovine herpesvirus type 4. | bovine herpesvirus type 4 (bhv-4) is a ubiquitous virus of cattle. its genome is a 144 +/- 6 kb double-stranded dna consisting of a unique central part (l-dna) flanked at both ends by tandem repeats called polyrepetitive dna (prdna or h-dna). the overall arrangement of genes has been obtained by the analysis of homologies between short bhv-4 dna sequences and corresponding genes of epstein-barr virus (ebv) and herpesvirus saimiri (hvs). the gene expression is temporally regulated. glycoprotein p ... | 1992 | 1336253 |
| role of human t-cell leukemia virus type 1 x region proteins in immortalization of primary human lymphocytes in culture. | human t-cell leukemia virus type 1 (htlv-1) immortalizes human cd4+ t lymphocytes in culture. previous studies show that in the context of a herpesvirus saimiri vector, the sequence of the x region at the 3' end of the htlv-1 genome is also capable of immortalizing cd4+ lymphocytes in the absence of htlv-1 structural proteins. the x region of htlv-1 encodes two trans-acting viral proteins, the 42-kda tax protein and the 27-kda rex protein. infection of human cord blood cells with herpesvirus sai ... | 1992 | 1351105 |
| herpesvirus saimiri has a gene specifying a homologue of the cellular membrane glycoprotein cd59. | herpesvirus saimiri (hsv) is a t-lymphotropic tumor virus that causes fulminant lymphomas and leukemias in various new world primates other than its natural host, the squirrel monkey (saimiri sciureus). in the course of completing the nucleotide sequence of its genome, we identified an open reading frame of 363 nucleotides, designated hvs-15, that has no detectable homology to any other viral sequences to date. hvs-15 encodes a 121-amino-acid protein which shows significant similarities to human ... | 1992 | 1382344 |
| activation of tyrosine kinase p60fyn following t cell antigen receptor cross-linking. | activation of t cells by specific antigens in the context of major histocompatibility complex encoded proteins is mediated by the t cell antigen receptor (tcr), consisting of a variable (ti) and an invariant (cd3) subunits. tyrosine phosphorylation is considered to be one of the earliest steps in tcr-mediated signal transduction. there are indications that the p60fyn protein tyrosine kinase is involved in signaling via tcr. however, enzymatic activation of the src-related tyrosine kinases upon t ... | 1992 | 1526965 |
| identification of transforming genes of subgroup a and c strains of herpesvirus saimiri. | herpesvirus saimiri is an oncogenic herpesvirus that induces rapidly progressing lymphomas in new world primates. using retrovirus vectors for gene transfer, specific open reading frames of h. saimiri were tested for their ability to transform rodent cells in culture. one open reading frame, designated stp-c488 (for saimiri-transformation-associated protein of the subgroup c strain 488), phenotypically transformed rat-1 cells, resulting in formation of foci, growth at reduced serum concentration ... | 1991 | 1651491 |
| a pair of selectable herpesvirus vectors for simultaneous gene expression in human lymphoid cells. | the genome of herpesvirus saimiri, a lymphotropic virus of non-human primates, was used to develop a vector system for transducing foreign genes into primary human t-cells and t-lymphoid cell lines. recombinant viruses were obtained by homologous recombination of the viral genome with linearized plasmid dna. the plasmid used contained a fragment of virion dna, a hygromycin-b-resistance marker (hyr), and a multiple cloning site for the insertion of additional expression cassettes. the resulting r ... | 1991 | 1651885 |
| persistence of selectable herpesvirus saimiri in various human haematopoietic and epithelial cell lines. | herpesvirus (h.) saimiri, an infectious agent of squirrel monkeys, is capable of persisting in t lymphocytes of various primate species. it has been used as a vector for the functional analysis of regulatory genes in primary human t lymphocytes. as it is not yet known whether other cell types are capable of supporting viral persistence, various human cell lines were investigated using selectable h. saimiri recombinants. the lines chosen represent cells from the epithelium and connective tissue a ... | 1991 | 1651988 |
| identification and characterization of the herpesvirus saimiri oncoprotein stp-c488. | the protein encoded by herpesvirus saimiri transforming gene stp-c488 was identified and characterized. antibodies were produced in rabbits by immunization with keyhole limpet hemocyanin-conjugated synthetic peptides specific for the predicted sequence of stp-c488. stp-c488-encoded protein was detected in recombinant escherichia coli, transformed rat-1 cells, transfected cos-1 cells, and in common marmoset t lymphocytes immortalized by herpesvirus saimiri strain 488. stp-c488 protein was sensiti ... | 1991 | 1658384 |
| expression of collagenlike sequences by a tumor virus, herpesvirus saimiri. | | 1991 | 1658399 |
| gene expression in cells infected with gammaherpesvirus saimiri: properties of transcripts from two immediate-early genes. | during productive infections of cells with the gammaherpesvirus, herpesvirus saimiri (hvs), a polyadenylated rna of 2.2-2.4 kb accumulates to form a large fraction of virus-specified rna. this transcript is from the virus thymidylate synthase (ts) gene and its synthesis, like that of late mrnas encoding the virus structural proteins, is sensitive to an inhibitor of virus dna synthesis (phosphonoacetic acid, paa). transcription which is insensitive to paa occurs from many parts of the hvs genome, ... | 1990 | 1699352 |
| regulation of the herpesvirus saimiri (hvs) delayed-early 110-kilodalton promoter by hvs immediate-early gene products and a homolog of the epstein-barr virus r trans activator. | we have reported previously the detection of two stable immediate-early (ie) transcripts that accumulate in cycloheximide-treated cells infected with herpesvirus saimiri (hvs). these are the 1.6-kb mrna from the 52-kda gene (which is homologous to the bslf2-bmlf1 gene of epstein-barr virus) and the 1.3-kb mrna from the hindiii-g fragment of virus dna. in order to study the roles of the hvs ie gene products in the progression of a lytic infection, the promoter region of the delayed-early 110-kda ... | 1991 | 1850023 |
| transformation by herpesvirus saimiri. | | 1991 | 1851376 |
| restriction endonuclease analysis of alcelaphine herpesvirus 1 dna and molecular cloning of virus genomic dna for potential diagnostic use. | alcelaphine herpesvirus 1 (ahv-1) genomic dna was analyzed using restriction enzymes having recognition sequences both low in guanine-cytosine content (bamhi, kpni, hindiii) and high in guanine-cytosine content (smai, avai, apai). the results from the restriction enzyme analyses along with exonuclease treatment demonstrated that the termini of ahv-1 dna are likely composed of polyrepetitive sequences high in guanine-cytosine content similar to those found in herpesvirus saimiri dna. cleaving ahv ... | 1990 | 1965581 |
| structure and expression of the woodchuck herpesvirus genome. | this report describes the genome structure and location from which immediate-early transcription originates in the recently characterized woodchuck herpesvirus (herpesvirus marmota: hvm). cross-hybridization of restriction fragments indicates that the hvm genome contains a tandem array of 1.5-kb repeat units. additionally, terminal labeling and exonuclease experiments demonstrate that the repeated sequences lie at the termini of the genome. hybridization of probes representing immediate-early tr ... | 1991 | 1984663 |
| human herpesvirus 6 is closely related to human cytomegalovirus. | a sequence of 21,858 base pairs from the genome of human herpesvirus 6 (hhv-6) strain u1102 is presented. the sequence has a mean composition of 41% g + c, and the observed frequency of cpg dinucleotides is close to that predicted from this mononucleotide composition. the sequence contains 17 complete open reading frames (orfs) and part of another at the 5' end of the sequence. the predicted protein products of two of these orfs have no recognizable homologs in the genomes of other sequenced hum ... | 1990 | 2152817 |
| structural organization of the conserved gene block of herpesvirus saimiri coding for dna polymerase, glycoprotein b, and major dna binding protein. | lymphotropic herpesviruses such as epstein-barr virus and herpesvirus saimiri are commonly grouped as gamma-herpesviruses, although overall genome organization and numerous biological properties are quite different in the viruses. to define the relationship more precisely, we sequenced the kpnl fragments f (6.5 kb) and c (9.8 kb) of the h.saimiri strain no. 11 genome; these dna fragments were found to contain the genes coding for equivalents of the major dna binding protein, a putative glycoprot ... | 1990 | 2154888 |
| the divergence between two oncogenic herpesvirus saimiri strains in a genomic region related to the transforming phenotype. | herpesvirus saimiri strains can be divided into at least three subgroups (a, b, c) based on sequence divergence at the left end of viral unique sequence dna. strains of subgroups a and c are highly oncogenic and readily transform simian t-lymphocytes in vitro to interleukin-2 independent growth, while subgroup b strains do not. a left terminal reading frame of a h. saimiri subgroup a strain was shown previously to correlate with the oncogenic phenotype and in vitro transforming potential; the de ... | 1990 | 2161148 |