Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| competition radioimmunoassay for mason-pfizer monkey virus: comparison with recent isolates. | the major core protein of mason-pfizer monkey virus was purified by deae ion exchange column chromatography and shown to be 27,000 daltons (p27). following the characterization of monospecific antisera prepared against p27, a radioimmunoassay was developed with these reagents and competition experiments were done with come of the recent m-pmy-like isolates as well as with other oncornaviruses. results suggest that three of the viruses tested, ao, x-381 and ftp-1, are similar to m-pmv while j-96 ... | 1975 | 49328 |
| biochemical properties of the bromodeoxyuridine-induced guinea pig virus. | the biophysical and biochemical properties of the virus particles released by guinea pig embryo cells treated with 5-bromo-2'-deoxyuridine (budr) have been compared to those of the b-type mouse mammary tumor virus (mmtv) and the c-type rauscher murine leukemia virus. the high-molecular-weight (60 to 70s) rna of the budr-induced guinea pig virus (gpv) has a molecular weight of 8 x 106 when measred by mixed agarose polyacylamide gel electrophoresis. the virus particles isolated from the tissue cul ... | 1975 | 51933 |
| transcription of 70s rna by dna polymerases from mammalian rna viruses. | dna polymerases purified by the same procedure from four mammalian rna viruses, simian sarcoma virus type 1, gibbon ape lymphoma virus, mason-pfizer monkey virus, and rauscher murine leukemia virus are capable of transcribing heteropolymeric regions of viral 70s rna without any other primer. in this reconstituted system the enzymes from simian sarcoma virus type 1, mason-pfizer monkey virus, and rauscher murine leukemia virus transcribe viral 70s rna almost as efficiently as the dna polymerase f ... | 1975 | 53295 |
| detection of simian type-c particles in mason-pfizer virus infected cultures. | a simian type-c virus has been detected in cultures chronically infected with mason-pfizer monkey virus (m-pmv). simultaneous budding of m-pmv and type-c virus particles from the same cells was observed in cultures incubated at 37 or 40 degrees c. however, the frequency of such cells was greater in cultures grown at 40 degrees c. although clusters of type-c viral buds were seen at the surface of the cells, extracellular mature type-c particles in cell pellets or concentrated virus preparations w ... | 1976 | 54406 |
| relationship between the mason-pfizer monkey virus and hela virus: immunoelectron microscopy. | envelope antigens of the mason-pfizer monkey virus (mpmv) and the morphologically similar hela virus, which is continuously produced in some hela cell lines, were compared by indirect immunoferritin techniques. antisera raised against mpmv and hela virus revealed cross-reacting antigenic specificities on the surfaces of both agents, and cross-absorption and end-point dilution techniques indicated the presence of identical envelope antigens. the results demonstrated a close relationship, if not a ... | 1976 | 56448 |
| isolation and characterization of an antigen of the bovine c-type virus. | by means of gel filtration and isoelectric focusing, an antigen of the bovine c-type leukemia virus was isolated in a highly purified form from extracts of infected cells. the antigen has a molecular weight of approximately 25,000 daltons and an isoelectric point of 6.4 to 6.6. in immunodiffusion experiments, the antigen forms a line of identity with an antigen extracted from highly purified bovine c-type leukemia virus by treatment with ether or triton x-100. as determined by immunodiffusion an ... | 1976 | 56993 |
| bovine leukemia virus: an exogenous rna oncogenic virus. | short-term cultures of bovine leukemic lymphocytes release virus particles with biochemical properties of rna oncogenic viruses. these particles, tentatively called bovine leukemia virus (blv), have a high molecular weight rna-reverse transcriptase complex and a density of 1.155 g/ml in sucrose solutions. molecular hybridizations between blv/[3h]cdna and several viral rnas show that blv is not related to mason-pfizer monkey virus, simian sarcoma associated virus, feline leukemia virus, or avian ... | 1976 | 57616 |
| equine infectious anemia virus: evidence favoring classification as a retravirus. | equine infectious anemia virus (eiav) has a density of 1.154 g/cm3 in sucrose a high-molecular-weight rna similar in size to rauscher murine leukemia virus, and an internal virion reverse transcriptase that utilizes the synthetic rna template poly(ra) but not the synthetic dna template poly(da), both with (dt)12 as primer. although capable of utilizing manganese at low concentrations (approximately 0.1 mm), eiav reverse transcriptase showed highest activity in the presence of 9 mm magnesium. the ... | 1976 | 61283 |
| a new class of genetically transmitted retravirus isolated from mus cervicolor. | the cocultivation of spleen cells from the southeast asian mouse, mus cervicolor, with heterologous cell lines has permitted the isolation of a new retravirus (designated m432) that can be transmitted to tissue culture cells of the laboratory mouse, m. musculus. cells infected with m432 contain cytoplasmic type a particles and budding forms with compact,spherical nucleoids; extracellular virions lack surface spikes and have a condensed, central core surrounded by an intermediate line. like other ... | 1976 | 62362 |
| detection, quantitation, and characterization of the major internal virion antigen of the bovine leukemia virus by radioimmunoassay. | the major internal polypeptide of the bovine leukemia virus (blv) was purified to homogeneity with the use of gel filtration and affinity chromatography. like previous results, the protein had a molecular weight of 25,000 daltons as determined by electrophoresis in polyacrylamide gels with sodium dodecyl sulfate. more than 90% of the 125i-labeled protein was precipitated by bovine sera that reacted in immunofluorescence tests with acetone-fixed blv-infected cells. in contrast, minimal precipitat ... | 1976 | 63563 |
| oncornavirus: isolation from a squirrel monkey (saimiri sciureus) lung culture. | an oncornavirus isolated from a squirrel monkey (saimiri sciureus) lung culture has a density of 1.16 to 1.17 grams per milliliter, contains 70s rna, and has an rna-directed dna polymerase that prefers mg2+ over mn2+ in an assay in which polyribocytidylate - oligodeoxyguanylate (12-18) is used as a synthetic template. morphologically, the virus resembles mason-pfizer monkey virus but is antigenically distinct from this virus. the virus grows in cells of human, chimpanzee, rhesus monkey, canine, ... | 1977 | 63993 |
| bovine leukemia virus: an exogenous rna oncogenic virus? | short term cultures of bovine leukemic lymphocytes release virus particles with biochemical properties of rna oncogenic viruses. these particles, tentatively called bovine leukemia virus (blv) have a high molecular weight-reverse transcriptase complex and a density averaging 1.155 g/ml in sucrose solutions. molecular hybridizations between blv-3h cdna and several viral rnas show that blv is not related to mason-pfizer monkey virus (mpmv) simian sarcoma associated virus (ssv-1) feline leukemia vi ... | 1976 | 64382 |
| expression of mason-pfizer and simian type c viruses in the presence of 5-iododeoxyuridine and dexamethasone. | production of infectious mason-pfizer monkey virus (m-pmv) was enhanced after treatment of the cmmt cell line with 2.5 x 10(-5) m dexamethasone phosphate (dxm). the reverse transcriptase (rt) activity and infectivity titers of treated culture fluids were enhanced by five- and tenfold, respectively. along with stimulation of m-pmv synthesis, a simian type c virus (scv) was also detected by electron microscopic and rt analyses. the scv was serologically related to the endogenous baboon type c viru ... | 1977 | 67214 |
| antigenic relatedness of the dna polymerase of human breast cancer particles to the enzyme of the mason-pfizer monkey virus. | we have previously reported [(ohno, t., sweet, r.w., hu, r., dejak, d. & spiegelman, s. (1977) proc. natl. acad. sci. usa 74, 764-768)] on the purification and characterization of the dna polymerase from human breast cancer particles. its preference for certain synthetic templates and its ability to use a viral rna to fashion a faithful dna transcript identify it as a reverse transcriptase similar to that found in the mouse mammary tumor virus and in the mason-pfizer monkey virus (mpmv). we repo ... | 1977 | 68475 |
| characterization of a retravirus isolated from squirrel monkeys. | a new retravirus (smrv) isolated from a squirrel monkey, saimiri sciureus, has an mg2+-dependen reverse transcriptase and a buoyant density of 1.17 g/cm3 in sucrose and 1.21 g/cm3 in cesium chloride, similar to the mouse mammary tumor virus and the mason-pfizer monkey virus. the polypeptide patter of smrv as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis was distinct from the reported polypeptide patterns of known retraviruses. four major polypeptides of molecular weight ... | 1977 | 69728 |
| production of antiserum to the reverse transcriptase of mason-pfizer monkey virus. | the reverse transcriptase of mason-pfizer monkey virus (m-pmv) has been isolated and partially purified by ion exchange chromatography. sera from rabbits immunized with the partially purified enzyme have been shown by microimmunodiffusion analysis to be immunologically specific for the m-pmv polymerase. the immune serum also specifically inhibits m-pmv polymerase activity and this inhibitory activity has been shown to reside in the igg fraction of the serum. the application of these reagents to ... | 1977 | 70506 |
| endogenous new world primate retrovirus: interspecies antigenic determinants shared with the major structural protein of type-d rna viruses of old world monkeys. | a reverse transcriptase-containing virus has recently been isolated from a squirrel monkey (saimiri sciureus). molecular hybridization studies demonstrate that the squirrel monkey retrovirus (smrv) is endogenous to this new world primate, yet lacks detectable nucleotide sequence homology with cellular dnas of representative old world primates or with the genomes of previously isolated old world primate retroviruses. the 35,000-dalton major structural protein (p35) of smrv was purified and shown ... | 1977 | 74833 |
| primate retroviruses: immunological cross-reactivity between major structural proteins of new and old world primate virus isolates. | the major 35,000-molecular-weight internal antigen (p35) of the squirrel monkey retrovirus (smrv) was isolated and partially characterized. immunological analysis of smrv p35 led to the demonstration of antigenic determinants common to smrv and the mason-pfizer monkey virus (mpmv). a broadly reactive competition immunoassay was developed utilizing antiserum to mpmv to precipitate 125i-labeled smrv p35. although the major structural proteins of mpmv and smrv competed with equal efficiency in this ... | 1978 | 76686 |
| primate retroviruses: envelope glycoproteins of endogenous type c and type d viruses possess common interspecies antigenic determinants. | the major 70,000- to 80,000-molecular-weight envelope glycoproteins of the squirrel monkey retrovirus, mason-pfizer monkey virus, and m7 baboon virus and the related endogenous feline virus, rd114, were isolated and immunologically characterized. immunoprecipitation and competition immunoassay analysis revealed these viral envelope glycoproteins to possess several distinct classes of immunological determinants. these include species-specific determinants, group-specific antigenic determinants un ... | 1978 | 77909 |
| type d retroviruses: occurrence of natural antibodies to mason-pfizer monkey virus in rhesus monkeys. | 1978 | 78569 | |
| [chronic infection caused by the simian mason-pfizer virus in primate cell cultures]. | cell cultures of monkey prepuce (rhfs) and african green monkey kidney (bsc-1) were infected once with simian mason-pfizer virus (mpv) and virus expression in the course of establishment of chronic infection was studied. the productive infection was characterized by changes in the cell metabolism (dna synthesis increased 2-3-fold as early as the "zero" passage), the appearance of gs-antigen, formation of virions of type d and high activity of rna-dependent dna-polymerase. multinuclear giant cell ... | 1978 | 78587 |
| demonstration of rna-dependent dna polymerase activity in non-disrupted type d-retravirus particles after treatment with edta. | the type d-retraviruses pmf virus (pmfv) and mason-pfizer moneky virus (mpmv) show rna-dependent dna polymerase (revertase) activity after treatment of the nondisrupted virions with the chelating agent ethylenediaminetetraacetate (edta). in the range of 1 to 5 mm, the effect is dependent on the concentration of edta. as compared with nonidet p40 disrupted particles treatment of pmfv with edta results in a revertase activity of about 65%. simultaneous addition of mg- or ca-ions prevents the edta ... | 1977 | 78610 |
| template-specific requirements for dna synthesis by the mason-pfizer monkey virus dna polymerase: unique aspects. | the biochemical properties of dna polymerase purified from mason-pfizer monkey virus were studied, with respect to synthetic and natural template-primer utilization. thes studies revealed the following new information about the mason-pfizer monkey virus enzyme: (a) mason-pfizer monkey virus polymerase was found to prefer template: primer molar nucleotide ratios of 2.5-5: 1 for optimal rates of synthesis with poly(c) .(dg)12-18 as template-primer. (b) poly(a)-directed synthesis was stimulated b ... | 1978 | 78724 |
| comparative large-scale propagation of retroviruses from old world (mason-pfizer monkey virus) and new world (squirrel monkey virus) primates. | a cell culture method is described for the large-scale (50 to 150 1) production of mason-pfizer monkey virus and squirrel monkey virus, two primate retroviruses. virus production was achieved with suspension cultures of chronically infected a204 human rhabdomyosarcoma cells harvested and clarified in the logarithmic stages of cell culture growth. methods for the subsequent purification and concentration of virus material utilizing zonal centrifugation also are described. applications of these me ... | 1978 | 78888 |
| comparison of mason-pfizer monkey virus and squirrel monkey (saimiri sciureus) retrovirus by immunoelectron microscopy. | comparison of mason-pfizer monkey virus and squirrel monkey retrovirus (both candidate type d oncornaviruses) by immunoelectron microscopy revealed that these two viruses do not share common surface antigens. | 1978 | 79657 |
| type d primate retroviruses: a review. | the prototype virus of the type d retroviruses is the mason-pfizer monkey virus (mpmv). mpmv was originally isolated from a breast carcinoma of a female rhesus monkey (an old world monkey). mpmv is of obvious importance in that it is the only retrovirus thus far isolated from a mammary tumor of a primate and has been shown to have transforming potential for primate cells in vitro. subsequent to the isolation of mpmv viruses morphologically and immunologically indistinguishable from mpmv have bee ... | 1978 | 80259 |
| serological definition of the lentivirus group of retroviruses. | the major polypeptides of visna viruses and other lentiviruses have been isolated and shown to be closely related if not identical in radioimmunoassays. by this criterion the lentiviruses form a distinct group of retroviruses unrelated to spuma viruses, mammalian and avian retroviruses that cause tumors, and unclassified retroviruses of cattle and horses. two sera obtained from goats immunized with mason-pfizer monkey virus or squirrel monkey virus reacted with visna p30. additional data suggest ... | 1979 | 85722 |
| the use of trypan blue for counterstaining in the sepharose bead immunofluorescence test. the application of the test for the demonstration of primate retrovirus-specific antibodies and antigens. | the sepharose bead immunoflurorescence test was performed by counterstaining the beads with trypan blue. this results in a red staining of negative beads which allows an easy distinction from positive green-fluorescent beads. sepharose beads conjugated with viral proteins or antiviral antibodies were used to demonstrate mason-pfizer monkey virus (mpmw)- and simian sarcoma virus (ssv) - specific antigens or antibodies. the test shows a high sensitivity and specificity and needs a small amount of ... | 1978 | 86253 |
| a new virion precipitation test for oncovirus envelope antigens which detects common antigenic determinants in mammalian type-c viruses and mason-pfizer monkey virus. | a method for the study of oncovirus envelope antigens was developed, bases on the precipitation of intact virions by a double antibody technique. the amount of precipitated virus was then measured as reverse transcriptase activity. the method was designated the virion precipitation test (vpt). it has been used for titration of antibodies to envelope antigens of oncoviruses. the study of envelop antigens of 11 different oncoviruses permitted their differentiation into the following groups: (1) mu ... | 1979 | 86521 |
| apparent allosterism by avian myeloblastosis virus reverse transcriptase and e. coli dna polymerase i. | a recent report (1) presented evidence for allosterism in reverse transcription by mason-pfizer monkey virus reverse transcriptase and by e. coli dna polymerase i. our experiments also demonstrate these apparent cooperative effects when synthesis is catalyzed by either avian myeloblastosis virus dna polymerase, feline sarcoma virus dna polymerase, or e. coli dna polymerase i (large fragment). we show that the apparent cooperativity depends on the use of oligo(dt)12-18 as primer. however, if the ... | 1979 | 86985 |
| virus-like particles and macromolecules in human milk and breast tumors. | relevant data pertaining to present evidence for virus-like particles and virus-related macromolecules in human milk and breast tumors are presented. a critical review and discussion of reported observations concerning virus-related macromolecules will include rna-directed dna polymerase, viral antigens, and rna related to murine mammary tumor virus and/or mason-pfizer monkey virus. from the standpoint of clinical applications, the finding of viral-related antigens in human breast tumors and evi ... | 1979 | 92388 |
| susceptibility of human cultured cells to mason-pfizer monkey virus. | mason-pfizer monkey virus (m-pmv), originally isolated from mammary carcinoma of a rhesus monkey, is infectious to various human cells in tissue culture. human epithelioid cells (hela and hep-2), fibroblastic cells (embryonic cells as well as virus-transformed embryonic rsb cells), and glial cells (kc) have all been infected with m-pmv. electron microscope studies have shown that all infected cells produce progeny virus. the titer of infectious m-pmv in cultures of hela and hep-2 cells assayed b ... | 1978 | 97115 |
| natural distribution of squirrel monkey retrovirus proviral sequences in primate dnas. | 3h-labelled 70s rna of squirrel monkey retrovirus (smrv) hybridized to a high degree (greater than 52%) to the dna of various tissues of two squirrel monkeys. hybridization of the same probe to dnas of other primates including new world monkeys (woolly monkey, capuchin, owl monkey), old world monkeys (rhesus, african green), apes (gibbon, chimpanzee), and human (a204 cells infected with mpmv) revealed no significant hybridization. analysis of the kinetics of hybridization indicated that smrv pro ... | 1978 | 99487 |
| the characterization of mason-pfizer monkey virus-induced cell fusion. | 1979 | 111409 | |
| characterization of infection and replication of mason-pfizer monkey virus in human cell cultures. | human cells derived from both normal and neoplastic tissues can be infected by mason-pfizer monkey virus (mpmv) without accompanying cytopathology. infection of cell cultures such as human rhabdomyosarcoma (a204) results in a persistenly infected cell line which can be subcultured over 30 sequential culture passages without significant change in phenotype properties according to reverse, transcriptase (rt), mpmv p27 antigen content, virus particle count and infectivity titre. productive virus in ... | 1979 | 118235 |
| studies on human kc cell syncytia formation induced by mason-pfizer monkey virus. | human kc cell monolayer inoculated with concentraten mason-pfizer monkey virus (mpmv) showed syncytia formation within an hour. the cell fusion was blocked by the treatment of the mpmv with neutralizing antiserum. treatment of the mpvm with beta-propiolactone resulted in the loss of infectivity although kc cell fusion ability of the virus still remained. kc cells inoculated with unconcentrated mpmv showed no cell fusion even after several transfers, although a chronic mpmv infection was establis ... | 1977 | 145160 |
| serological analysis of an oncornavirus (pmf virus) detected in malignant permanent human cell lines. | immunodiffusion analysis of the pmf virus which was detected in malignant permanent human cell lines revealed positive reactions with antisera against the mason-pfizer monkey virus (mpmv). no cross-reactivity was demonstrated with murine leukemia virus (mulv), rat leukemia virus (ralv), hamster leukemia virus (halv), feline leukemia virus (felv), simian (woolly monkey) sarcoma virus (ssv-1) and mouse mammary tumor virus (mtv). the cross-reactive antigens of the pmf virus and the mpmv are conside ... | 1975 | 171892 |
| sialylatin of glycoproteins of murine mammary tumor virus, murine leukemia virus, and mason-pfizer monkey virus. | neuraminidase treatment of mouse mammary tumor virus, rauscher murine leukemia virus, and mason-pfizer monkey virus resulted in loss of their capacity to inhibit hemagglutination of influenza virus. hemagglutination-inhibition activity of these rna tumor viruses could be restored by in vitro resialylation catalyzed by sialyl transferase. the major glycoprotein in the intact envelope of desialylated and, to some extent, native virions could be specificallly labeled in vitro with cmp-(14c) sialic ... | 1976 | 178911 |
| immunological cross reactivity of mason-pfizer monkey virus with type c rna viruses endogenous to primates. | 1976 | 180419 | |
| cellular hypersensitivity of gp55 of riii-murine mammary tumor virus and gp55-like protein of human breast cancers. | previous studies suggested that immunogenic breast cancer tissues contained a component(s) that is antigenically similar to some component of murine mammary tumor virus (mumtv) and resembles the glycoprotein, m.w. 55,000 (gp55), of riii-mumtv in molecular weight and charge density. this investigation measured in vitro cellular hypersensitivity responses of breast cancer patients to riii mouse milk, purified riii-gp55, c3h-mumtv, autologous and homologous breast cancer tissues, gp50 of a-mumtv, a ... | 1976 | 184925 |
| oncornavirus-like particles in baboon type c virus-infected chimpanzee lung cells (sfre:cl-1). | intracytoplasmic type a particles were observed in a fetal chimpanzee lung culture (sfre:cl-1) inoculated with type c virus-containing supernatants from a coculture of baboon placenta and sfre:cl-1 cells. budding, immature, and mature type c particles were also noted. in thin section, spike-like structures were rarely detected on budding intracytoplasmic type a particles but were occasionally observed on some immature and mature virus particles. unlike mouse mammary tumor virus or mason-pfizer m ... | 1976 | 186614 |
| interspecies radioimmunoassay for the major structural proteins of primate type-d retroviruses. | a competition radioimmunoassay has been developed in which type-d retroviruses from three primate species compete. the assay utilizes the major structural protein (36,000 daltons) of the endogenous squirrel monkey retrovirus and antisera directed against the major structural protein (27,000 daltons) of the mason-pfizer monkey virus isolated from rhesus monkeys. purified preparations of both viruses grown in heterologous cells, as well as extracts of heterologous cells infected with squirrel monk ... | 1977 | 202962 |
| cell-mediated immune response to simian oncornavirus antigens in pregnant women. | tritiated thymidine incorporation into lymphocytes of 118 adult women was studied in the presence of mitomycin c-treated cells prepared from cell lines continuously producing mason-pfizer monkey virus (mpmv), baboon c-particle virus, or simian sarcoma virus (ssv) and in the presence of control cell lines documented for the absence of oncornaviruses. at the end of pregnancy, women who had 5-9 pregnancies showed a high frequency (53%) of specific positive responses to cells with mpmv antigens. the ... | 1978 | 203708 |
| detection in human breast carcinomas of an antigen immunologically related to a group-specific antigen of mouse mammary tumor virus. | an antigen immunologically related to a group-specific antigen (gp52, a 52,000-dalton glycoprotein) of the mouse mammary tumor virus has been identified in paraffin sections of human breast cancers by means of the indirect immunoperoxidase technique. the specificity of the reaction with antibody against mouse mammary tumor virus was examined by absorption of the igg with the following: (a) purified gp52; (b) a number of virus preparations (mouse mammary tumor virus, rauscher leukemia virus, simi ... | 1978 | 206905 |
| detection of mason-pfizer monkey virus infection by syncytia formation of human cells doubly transformed by rous sarcoma virus and simian virus 40. | human cells doubly transformed by rous sarcoma virus and sv40 (rsb cells) formed syncytia by cocultivation with mason-pfizer monkey virus (mpmv)-producing cells. this cell fusion was blocked by anti-mpmv serum indicating that the phenomenon is mpmv specific. the rsb cells were successfully used for mpmv infectivity assay in the same manner as kc cells. | 1978 | 208492 |
| spontaneous esophageal carcinoma and epithelial cell line of an adult rhesus monkey. | a continuous epithelial cell line, 816a, was established from a lymph node of an adult rhesus monkey with metastatic esophageal carcinoma. these cells are characterized by the presence of desmosomes and a markedly heteroploid karyotype. at a relatively early culture age, electron microscopy showed both budding and extracellular type c virus. antigen reactive with antisera to mason-pfizer monkey virus was observed by complement-fixation. the level of this antigen decreased with increased culture ... | 1978 | 210934 |
| specificity of response to viral proteins in horses infected with equine infectious anemia virus. | three structural proteins of equine infectious anemia virus were purified, labeled with 125i, and utilized in radioimmunoassays with horse sera and antisera to heterologous retroviruses. whereas radioimmunoassay titers for the major protein, p25, were 500- to 1,000-fold higher than titers in immunodiffusion, for clinical purposes these two procedures were equivalent. antibodies to two low-molecular-weight proteins, p12 and p10, were also found in infected horses, but with a lower frequency and l ... | 1979 | 217831 |
| sequence homology of nucleic acids from human breast cancer cells and complementary dna's from murine mammary tumor virus and mason-pfizer monkey virus. | simultaneous presence of murine mammary tumor virus- and mason-pfizer monkey virus-specific sequences has been detected in nucleic acids isolated from some human breast tumors and from mcf-7 cells, a well-characterized human breast cancer cell line. carefully characterized long complementary dna transcripts were used in the molecular hybridization experiments. from the data that are presently available, it would appear that when homology is detected with one of the mammary tumor probes the other ... | 1979 | 227595 |
| conserved region of mammalian retrovirus rna. | the viral rnas of various mammalian retroviruses contain highly conserved sequences close to their 3' ends. this was demonstrated by interviral molecular hybridization between fractionated viral complementary dna (cdna) and rna. cdna near the 3' end (cdna(3')) from a rat virus (rpl strain) was fractionated by size and mixed with mouse virus rna (rauscher leukemia virus). no hybridization occurred with total cdna (cdna(total)), in agreement with previous results, but a cross-reacting sequence was ... | 1979 | 229272 |
| purification and characterization of the dna polymerase of human breast cancer particles. | previous studies have identified human breast tumor particles possessing many of the features characteristic of rna tumor viruses. in addition to the expected size (600 s) and density (1.16 g/ml) these include possession of an outer membrane and an inner one surrounding a "core" containing a dna polymerase and a large-molecular-weight (70s) rna possessing detectable homology to the rnas of the mouse mammary tumor virus (mmtv) and of the mason-pfizer monkey virus (mpmv). we report here the purifi ... | 1977 | 265540 |
| cross-reaction between antigens of human myelogenous leukemia and mason-pfizer monkey virus. | 1977 | 271610 | |
| serological evidence for antigenic differences between the mason-pfizer monkey virus (mpmv) and an mpmv-like virus (pmfv) detected in a malignant permanent human cell line. | 1979 | 369867 | |
| radioimmunoassay for the major structural protein of mason-pfizer monkey virus: attempts to detect the presence of antigen or antibody in humans. | the 25,000 dalton protein of mason-pfizer monkey virus (mpmv) was isolated by gel filtration chromatography. in agreement with results from other laboratories, antisera to type-c and the non-type-c bovine leukemia and equine infectious anemia viruses did not precipitate 125i-labelled mpmv p25. in addition, these viruses did not cross-react in a competition radioimmunoassay for mpmv p25. twenty-one human tissues (15 breast carcinomas, 2 normal breasts, 3 acute myelogenous leukemias and 1 sarcoma) ... | 1977 | 403148 |
| oncornavirus-like particles in squirrel monkey (saimiri sciureus) placenta and placenta culture. | oncornavirus-like particles similar in morphology to type d particles were observed in 1 of 2 squirrel monkey (saimiri sciureus) placentas. intracytoplasmic type a particles, immature virus particles, and mature viruses with eccentric or occasionally centric nucleoids were associated with placental syncytiotrophoblasts. a spike layer typical of type b viruses was not detected in viral envelopes. onvornaviruses, identical to those previously isolated from squirrel monkey tissues and similar to ma ... | 1977 | 408507 |
| [differentiation of type d virus from continuous human cells (il'in-bykovskiĭ virus) and mason-pfizer monkey virus by the antigens of the viral envelopes]. | for differentiation of ilvin-bykovsky virus (ibv) and monkey meson-pfeizer virus (m-pmv) the method of virus neutralization with antibodies against the envelope virus antigen was used. the viruses were cultivated in similar human embryo cells. the results of the virus neutralization were determined by presence or absence of the gs-antigen in the infected cells. the antiserum to m-pmv envelope antigens did not neutralize the ibv antigen. it has been concluded that ibv and m-pmv differ by their en ... | 1977 | 409444 |
| squirrel monkey retrovirus: electron microscopy of a virus from new world monkeys and comparison with mason-pfizer monkey virus. | the ultrastructural morphogenesis of squirrel monkey retrovirus (smrv) and mason-pfizer monkey virus (mpmv) growth in cell culture were compared. both viruses develop by a process that begins with the formation of intracytoplasmic a particles which are then enveloped at the plasma membrane during budding. smrv also develops as a crescent-shaped nucleoid beneath a bulging plasma membrane, a development characteristic of type c oncornaviruses. free extra-cellular mature smrv was generally round wi ... | 1978 | 417701 |
| the leukocyte migration inhibition response to certain breast cancer-related antigens (mcf-7 and mumtv): their potential as discriminants. | certain oncogenic viruses have been implicated in human breast cancer, including the murine mammary tumor virus (mumtv) and the mason-pfizer monkey virus (mpmv). we have used the leukocyte migration inhibition (lmi) response to assay the response to several potential breast cancer-related antigens, including mumtv, mpmv, and a breast cancer cultured cell line, mcf-7, in 96 breast cancer patients, in 32 women with benign breast disease, and in 67 normal women. the lowest tenth percentile of contr ... | 1979 | 462374 |
| rna subunit structure of mason-pfizer monkey virus. | mason-pfizer monkey virus 60-70s rna has a molecular weight of 8 times 10-6 when analyzed on polyacrylamide gels. dissociation of 60-70s rna of mason-pfizer monkey virus and murine leukemia virus by heat or formamide (40%) resulted in conversion to identical subunit structures of 2.8 times 10-6 daltons; treatment with lower amounts of formamide revealed a partial dissociation of mason-pfizer monkey virus 60-70s rna released three low-molecular-weight rna species of 10-5, 3,5 times 10-4, and 2.5 ... | 1975 | 803570 |
| responses of infant rhesus monkeys to inoculation with mason-pfizer monkey virus materials. | rhesus monkeys neonatally inoculated with mason-pfizer monkey virus (m-pmv) and virus-infected cells frequently developed viral and/or bacterial pneumonia and enteritis. three characteristic hematologic patterns occurred among the inoculated animals and correlated well with the probability of survival. postmortem examination of the animals revealed lymphadenopathy and thymic atrophy. m-pmv was present in lymph nodes, blood, brain, spleen, thymus, kidneys, and bone marrow. the disease induced in ... | 1975 | 804565 |
| mason-pfizer monkey virus: analysis and localization of virion proteins and glycoproteins. | the polypeptide composition of mason-pfizer monkey virus was determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. six major polypeptides of molecular weights 68,000, 27,000, 20,000, 14,000, 12,000, and 10,000 were resolved regardless of the cell type (i.e., two human and two rhesus) in which the virus was grown. protein gp68 (68,000) represented the major virus glycoprotein and protein gp20 (20,000) represented a minor glycoprotein of the virion, again regardless of the ce ... | 1975 | 810603 |
| [human d(b) type virus: comparison of d(b) type virus antigens with antigens of oncornaviruses of different origins]. | it was found by the immunodiffusion test that the d(b) type virus isolated from human cell lines and mason-pfizer monkey virus (m--pmv) contained common group-specific antigen(s). no cross-reaction was demonstrated between this d(b) type virus and c type oncornaviruses of various origins. | 1976 | 816086 |
| antigenic analysis of the major structural protein of the mason-pfizer monkey virus. | the major internal protein, p27 (m.w. 27,000 daltons) of the mason-pfizer monkey virus (mpmv) was purified by gel filtration and ion-exchange chromatography and then used to develop a radioimmunoassay (ria). this ria was specific for mpmv because no immunologic cross-reactivity was observed between p27 of mpmv and 13 different rna tumor viruses of mammalian and avian origin. however, the p27 of mpmv grown in three different primate cells exhibited identical antigenic cross-reactivity. in additio ... | 1976 | 819581 |
| immunological relationship between an oncornavirus isolate from hep-2 cells, mason-pfizer monkey virus, and human tumor cells. | 1975 | 822825 | |
| [detection of the gs-antigen of d-type virus in the cells of human breast fibroadenoma]. | gs-antigen(s) of the d-type virus isolated from the continuous cells of human carcinoma was detected by the immunodiffusion with an indirect radioimmunoautographic assay in 5 of 7 human breast fibroadenoma. this virus contained gs-antigen common with the mpmv. these data demonstrated the genom of the d-type virus (or of a similar virus) to be integrated with the human fibroadenoma cells genom. expression of the virus genom takes place at least to the level of the virus gs-antigen synthesis. the ... | 1976 | 829403 |
| mutational analysis of the major homology region of mason-pfizer monkey virus by use of saturation mutagenesis. | the major capsid (ca) protein of retroviruses possesses a stretch of 20 amino acids, called the major homology region (mhr), which is evolutionarily conserved and invariant in location within the primary sequence of the protein. the function of this region was investigated by examining the effect of random single-amino-acid substitutions within the central 13 positions of the mhr on the life cycle of mason-pfizer monkey virus (m-pmv), an immunosuppressive d-type retrovirus. when these mutants we ... | 1992 | 1279197 |
| mutations within the env gene of mason-pfizer monkey virus: effects on protein transport and su-tm association. | by deletion mutagenesis analyses, we have examined the contribution of the immunosuppressive peptide (isp) region within the transmembrane (tm) protein of mason-pfizer monkey virus to viral maturation and infectivity. deletion of the entire region (mutant d105) results in the production of an env precursor that is transport defective and therefore unable to be processed to mature glycoproteins. this mutation results in the release of noninfectious virions devoid of surface glycoproteins. a secon ... | 1992 | 1316462 |
| protein of macaques against infection with simian type d retrovirus (srv-1) by immunization with recombinant vaccinia virus expressing the envelope glycoproteins of either srv-1 or mason-pfizer monkey virus (srv-3). | rhesus macaques were immunized with live vaccinia virus recombinants expressing the envelope glycoproteins (gp70 and gp22) of simian type d retrovirus (srv), serotype 1 or 3. all of the animals immunized with either the srv-1 env or the srv-3 env vaccinia virus recombinant developed neutralizing antibodies against the homologous srv. in addition, both groups developed cross-reactive antibodies and were protected against an intravenous live-virus challenge with srv-1. the four control animals imm ... | 1992 | 1316495 |
| identification of a generalised packaging sequence for d-type retroviruses and generation of a d-type retroviral vector. | in order to construct vectors based upon d-type, rather than c-type, retroviruses, we have identified a 624-bp fragment of mason-pfizer monkey virus (mpmv) which constitutes a packaging sequence for at least two d-type retroviruses. when this fragment was included in an extensively deleted d-type vector genome, the d-type viruses mpmv and srv-5, but not the c-type viruses mlv-a or mlv-e, rescued the vector rna from hela cells. the recombinant virus stocks have the host range of the rescuing d-ty ... | 1992 | 1322603 |
| investigations into the mechanism by which sulfated polysaccharides inhibit hiv infection in vitro. | sulfated polysaccharides have been shown to inhibit human immunodeficiency virus (hiv) infection in vitro. dextrin sulfate, fucoidan, and dextran sulfate fail to neutralize virions directly, but interact with target cells to inhibit virus entry. ionic interactions of sulfated polyanions with oppositely charged cell surface components, including cd4, have been assumed to be the inhibitory mechanism. it is shown that the sulfated polysaccharides inhibit infection of both cd4+ and cd4- cell lines b ... | 1992 | 1346567 |
| studies on a type d retrovirus isolated from an aids patient lymphoma. | the development of aids-related lymphomas (arl) has been on the rise in recent years. during an analysis of arl from aids patients, one individual developed atypical syncytial variants of high-grade burkitt's-type b-cell lymphomas, which prompted further study. however, the search for a hiv-1 retrovirus, which we hypothesized was infecting these cells, led to the subsequent discovery of a type d retrovirus in two early-passage lymphoma cell lines derived from this patient. nucleotide and amino a ... | 1992 | 1381207 |
| importance of p12 protein in mason-pfizer monkey virus assembly and infectivity. | mason-pfizer monkey virus (m-pmv) represents the prototype type d retrovirus, characterized by the assembly of intracytoplasmic a-type particles within the infected-cell cytoplasm. these immature particles migrate to the plasma membrane, where they are released by budding. the gag gene of m-pmv encodes a novel protein, p12, just 5' of the major capsid protein (ca) p27 on the polyprotein precursor. the function of p12 is not known, but an equivalent protein is found in mouse mammary tumor virus a ... | 1992 | 1433505 |
| a viral protease-mediated cleavage of the transmembrane glycoprotein of mason-pfizer monkey virus can be suppressed by mutations within the matrix protein. | the envelope glycoprotein precursor of retroviruses undergoes proteolytic cleavage in the golgi complex to yield the mature surface and transmembrane (tm) glycoproteins of the virus. we report here that the tm glycoprotein of mason-pfizer monkey virus undergoes a second proteolytic processing event during a late maturation step that can follow virus release and gag polyprotein cleavage. cleavage results in the conversion of the cell-associated tm glycoprotein (gp22) to a virus-associated gp20. p ... | 1992 | 1565636 |
| effect of retroviral proteinase inhibitors on mason-pfizer monkey virus maturation and transmembrane glycoprotein cleavage. | mason-pfizer monkey virus (m-pmv) is the prototype type d retrovirus which preassembles immature intracytoplasmic type a particles within the infected cell cytoplasm. intracytoplasmic type a particles are composed of uncleaved polyprotein precursors which upon release are cleaved by the viral proteinase to their constituent mature proteins. this results in a morphological change in the virion described as maturation. we have investigated the role of the viral proteinase in virus maturation and i ... | 1992 | 1602542 |
| antibodies to gag gene coded polypeptides of type d retroviruses in healthy people from guinea-bissau. | antibodies to proteins of mason-pfizer monkey virus (m-pmv) were screened in sera from 61 healthy donors living in guinea-bissau (4 hiv-1 and hiv-2 antibody positive hiv = human immunodeficiency virus), from 19 healthy french european blood donors, and from 9 french patients with induced immunodeficiency prior to bone marrow transplantation (all hiv-1 antibody negative). in 30 (49%) of the african sera tested, antibodies reacting against p27 and/or p14 were detected by western blot. some of thes ... | 1991 | 1650766 |
| rna pseudoknots downstream of the frameshift sites of retroviruses. | rna pseudoknot structural motifs could have implications for a wide range of biological processes of rnas. in this study, the potential rna pseudoknots just downstream from the known and suspected retroviral frame-shift sites were predicted in the rous sarcoma virus, primate immunodeficiency viruses (hiv-1, hiv-2, and siv), equine infectious anemia virus, visna virus, bovine leukemia virus, human t-cell leukemia virus (types i and ii), mouse mammary tumor virus, mason-pfizer monkey virus, and si ... | 1991 | 1663382 |
| the use of primers from highly conserved pol regions to identify uncharacterized retroviruses by the polymerase chain reaction. | two degenerate oligonucleotide primers derived from regions of pol conserved among retroviruses have been synthesized. polymerase chain reactions utilizing these primers amplify a 135-bp pol fragment in every retrovirus dna tested to date. the polymerase chain reaction has been linked to a reverse transcriptase step so that a pol-specific dna fragment can be obtained from a moderate amount of a purified retrovirus or viral rna. the identity of an unknown retrovirus can be determined by sequencin ... | 1990 | 1693369 |
| amino acid substitutions within the matrix protein of type d retroviruses affect assembly, transport and membrane association of a capsid. | the functional roles of the matrix (ma) protein in the assembly and maturation of retroviruses was investigated with a series of ma mutants of mason-pfizer monkey virus (m-pmv), an immunosuppressive type d retrovirus. the mutants we describe here were generated by the introduction of random point mutations within the ma coding domain by use of sodium bisulphite mutagenesis. studies of these mutants show that the ma protein plays a critical role in three different, sequential events in the final ... | 1991 | 1705884 |
| enzootic nasal tumour of goats: demonstration of a type d-related retrovirus in nasal fluids and tumours. | nasal exudate and tumour tissue from goats with enzootic nasal tumours were shown to contain a reverse transcriptase activity associated with a particle of buoyant density typical of retroviruses. the same particle contained a 25,000 mr protein that cross-reacted with the p27 of mason-pfizer monkey virus (mpmv) and with p25 of sheep pulmonary adenomatosis retrovirus. it also contained a low mr protein related to p10-12 of mpmv. | 1991 | 1717643 |
| isolation of a type d retrovirus from b-cell lymphomas of a patient with aids. | an atypical syncytial variant of a high-grade burkitt's-type b-cell lymphoma from a patient with aids who was seropositive for human immunodeficiency virus type 1 was studied. a productive type d retrovirus infection was identified in early-passage cell lines derived from two lymphomas from this patient. nucleotide and amino acid sequence analysis as well as immunologic reactivity indicated that the isolated virus was highly related to mason-pfizer monkey virus (mpmv). mpmv is an immunosuppressi ... | 1991 | 1717707 |
| tightly bound zinc in human immunodeficiency virus type 1, human t-cell leukemia virus type i, and other retroviruses. | human immunodeficiency virus type 1 (hiv-1) and human t-cell leukemia virus type i (htlv-i) were purified by sucrose density gradient centrifugation in the presence of 1 mm edta. pelleted gradient fractions were analyzed for total protein, total gag capsid protein, and total zinc. zinc was found to copurify and concentrate with the virus particles. through successive cycles of resuspending in buffer containing edta and repelleting, the zinc content remained constant at about 1.7 mol of zinc per ... | 1992 | 1731111 |
| retroviral pseudotypes produced by rescue of a moloney murine leukemia virus vector by c-type, but not d-type, retroviruses. | human hos cells containing a moloney murine leukemia virus (mo-mlv) recombinant genome were infected by a panel of retroviruses. the c-type viruses simian sarcoma associated virus, feline leukemia virus subgroup b, and the feline endogenous virus rd114 were able to form pseudotypes with the mo-mlv genome, which transferred a selectable marker gene to target cells; however, human t cell leukemia virus-1 and the d-type viruses mason-pfizer monkey virus and simian retrovirus-1 failed to rescue the ... | 1992 | 1733113 |
| use of molecular cloned viral genomes for studies into interrelationship between type d retroviruses from monkey and human cells. | type d retroviruses constitute a group of rna tumor viruses so far isolated exclusively from primates. 4 groups of isolates are known to date (mason-pfizer virus, agents of simian acquired immunodeficiency syndrome--saids, endogenous viruses of old world and new world monkeys, and some isolates from cell lines--pmf virus). the members of the latter group are well characterized at protein-chemical and immunological levels. briefly described in this paper are the results of our studies into the mo ... | 1990 | 2129382 |
| a linkage map of endogenous murine leukemia proviruses. | thirty endogenous proviruses belonging to the modified polytropic (mpmv) class of murine leukemia virus (mlv) were identified by proviral-cellular dna junction fragment segregation in several sets of recombinant inbred mice. twenty-six mpmv loci were mapped to chromosomal regions by matching proviral strain distribution patterns to those of previously assigned genes. like other endogenous nonecotropic mlvs, mpmv loci were present on several chromosomes in all strains examined. we pooled recombin ... | 1990 | 2155154 |
| a single amino acid substitution within the matrix protein of a type d retrovirus converts its morphogenesis to that of a type c retrovirus. | two different morphogenic processes of retroviral capsid assembly have been observed: the capsid is either assembled at the plasma membrane during the budding process (type c), or preassembled within the cytoplasm (types b and d). we describe here a gag mutant of mason-pfizer monkey virus, a type d retrovirus, in which a tryptophan substituted for an arginine in the matrix protein results in efficient assembly of capsids at the plasma membrane through a morphogenic process similar to that of typ ... | 1990 | 2170021 |
| detection and quantitation of a type d retrovirus gag protein in ovine pulmonary carcinoma (sheep pulmonary adenomatosis) by means of a competition radioimmunoassay. | a heterologous competition radioimmunoassay (ria) which consisted of 125i-labeled langur retrovirus major gag protein and goat anti-squirrel monkey retrovirus serum was used to detect a type d retrovirus-associated antigen in tumor cell homogenates, lung fluid, and cell culture supernatant fluids of naturally occurring and experimentally-induced ovine pulmonary carcinoma (opc, sheep pulmonary adenomatosis). in this assay, there was no cross reactivity between structural proteins of the type d re ... | 1990 | 2247933 |
| preassembled capsids of type d retroviruses contain a signal sufficient for targeting specifically to the plasma membrane. | the capsids of mason-pfizer monkey virus (m-pmv), an immunosuppressive type d retrovirus, are preassembled in the infected cell cytoplasm and are then transported to the plasma membrane, where they are enveloped in a virus glycoprotein-containing lipid bilayer. the role of viral glycoprotein in intracellular transport of m-pmv capsids was investigated with a spontaneous mutant (5a) of m-pmv, which we show here to be defective in envelope glycoprotein biosynthesis. dna sequence analysis of the en ... | 1990 | 2370682 |
| teleocidin, a tumour promoter, stimulates synthesis of primate retroviruses in persistently infected human cells. | the naturally occurring tumour promoter teleocidin produces a pronounced but transient enhancement of the synthesis of extracellular viral particles in human cells chronically infected with simian retroviruses of type c (baboon endogenous virus, simian sarcoma virus) or type d (mason-pfizer monkey virus) or a human cell line-derived type d isolate (pmf virus), respectively. the retrovirus-stimulating activity of teleocidin is very similar to that previously described for the tumour-promoting pho ... | 1985 | 2415081 |
| biochemical and immunological characterization of suncus murinus mammary tumor virus dna polymerase. | enzymological properties of the rna-directed dna polymerase associated with the suncus murinus mammary tumor virus (sm-mtv) was investigated and its antigenic relatedness to other retroviral dna polymerases was examined. the enzyme exhibited higher activity in the presence of mg2+ than in the presence of mn2+ with endogenous rna as well as with almost all of the synthetic template x primers tested. mg2+ was also effective with poly(2'-o-methylcytidylate) x oligodeoxyguanylate which was known to ... | 1986 | 2417416 |
| nucleotide sequence of mason-pfizer monkey virus: an immunosuppressive d-type retrovirus. | the genetic structure of mason-pfizer monkey virus (mpmv), a d-type retrovirus, has been determined. in addition to the viral gag, pol, and env genes is an orf overlapping both gag and pol and that encodes the viral protease. surprisingly, the mpmv env protein is highly homologous to that of the avian c-type virus, reticuloendotheliosis associated virus rev-a. the env sequence encodes an immunosuppressive peptide, which suggests that mpmv, like rev-a, may transiently induce a t-suppressor cell p ... | 1986 | 2421920 |
| sequence relationships of type d retroviruses which cause simian acquired immunodeficiency syndrome. | simian acquired immunodeficiency syndrome (saids) in macaque monkeys is caused by type d retroviruses; three independent virus isolates are identified as srv-1 (saids retrovirus-serotype 1), srv-2, and mpmv (mason-pfizer monkey virus). virions from these three isolates have serologically related core antigens, but distinct surface proteins. also, srv-2 is unique since it apparently induces retroperitoneal fibromatosis in addition to saids. the complete dna sequence of molecularly cloned srv-2 is ... | 1987 | 2435057 |
| major structural polypeptides of retrovirus produced by a suncus murinus mammary tumor cell line and type d retrovirus share interspecies antigenic determinants. | constitutive polypeptides of retrovirus produced by a suncus murinus mammary tumor cell line (sm-mtv) were characterized by immunofluorescence and immunoblotting. the major structural polypeptide of sm-mtv, molecular weight 44/43k, immunologically cross reacted with the structural polypeptides of mason-pfizer monkey virus (mpmv) (molecular weights 27k and 12/10k). sm-mtv constitutive polypeptides did not show antigenic relatedness with those of the following mammalian retroviruses: murine mammar ... | 1988 | 2460996 |
| the human non-lineage antigen cd46 (huly-m5) and primate retroviral gp70 molecules share protein-defined antigenic determinants. | the cd46 lymphocyte surface antigen of man (until recently called huly-m5), and defined by the e4.3 monoclonal antibody (moab), shares cross-reactive antigenic epitopes with the envelope gp70 glycoproteins of gibbon ape leukaemia virus (galv) and mason pfizer monkey virus (mpmv) primate retroviruses. it is now shown that the cross-reactive antigenic epitope shared by these three molecules is determined solely by the protein portion of these glycoproteins, and that the n-linked and o-linked carbo ... | 1989 | 2482250 |
| [simian aids virus: review]. | the review article on simian aids viruses compiles the presently known facts of aids-related simian retroviruses causing immunodeficiencies or lymphomas in nonhuman primates. they are also compared to the situation in man. simian acquired immunodeficiencies or lymphoproliferative diseases can be caused by infectious (exogenous) oncoviruses (c- or d-type) or by lentiviruses. infectious d-type oncoviruses of simian origin are: mason-pfizer monkey virus (mpmv), simian retrovirus type 1 (srv-1), sim ... | 1989 | 2559560 |
| a rapid screening procedure for the isolation of nonconditional replication mutants of mason-pfizer monkey virus: identification of a mutant defective in pol. | a rapid, sensitive, and reproducible method for the isolation of human cell clones containing nonconditional, replication-defective (rd) mutants of mason-pfizer monkey virus (m-pmv), the prototype of the d-type retroviruses is described. the two mutants, rd1 and rd2, thus far isolated have been analyzed for virus particle production (using radiolabeled precursors and by electron microscopy) and for the status of intracellular viral precursors. thin sections of rd1 and rd2 infected cells showed t ... | 1985 | 2579506 |
| evaluation of type d retroviruses as diagnostic tools in hiv infections. | a type d retrovirus isolated from a permanent human cell line (pmfv) was employed as diagnostic reagent both in southern transfer hybridization experiments using the cloned genome as a probe and in immunoblot analysis using sds disrupted virus particles. hybridization experiments performed under conditions of different stringencies revealed a close homology of pmfv to saids type d retroviruses of serotype 1 (srv-1, saids retrovirus d/ne), a related homology to the prototype type d virus (mpmv) a ... | 1989 | 2619725 |
| a homologue of retroviral pseudoproteases in the parapoxvirus, orf virus. | the nucleotide sequence of a near-terminal region of orf virus dna was determined. examination of the sequence revealed an open reading frame encoding a peptide with significant amino acid homology to the pseudoprotease domains recently identified in a number of retroviruses including mouse mammary tumor virus, simian mason-pfizer virus, maedi-visna virus, and equine infectious anaemia virus. the orf virus pseudoprotease shares up to 28% amino acid homology with retroviral pseudoproteases and ap ... | 1989 | 2678731 |
| some characteristics of a retrovirus isolated from transformed bovine cells. | a novel retrovirus has been isolated from bovine cells transformed after cocultivation with leukocytes from an animal suffering from sheep-associated bovine malignant catarrhal fever. morphologically and in its morphogenesis the virus resembles the type d mason-pfizer monkey virus (mpmv) as well as the ovine jaagsiekte retrovirus (jsrv). it is also serologically related to these two viruses, whereas a relationship to other known bovine retroviruses was not detected. however, its density of 1.16 ... | 1989 | 2763459 |
| molecular cloning of a type d retrovirus from human cells (pmfv) and its homology to simian acquired immunodeficiency type d retroviruses. | unintegrated circular proviral dna of a type d retrovirus (pmfv) isolated from a permanent human cell line was molecularly cloned in the bacteriophage vector l47.1 and subcloned in the plasmid vector pgem-2. a restriction endonuclease map of pmfv dna was established using 10 different enzymes for single and multiple digestions of closed circular and cloned dna molecules. by restriction endonuclease analysis cloned pmfv dna represented full-length viral dna with one long terminal repeat (ltr). th ... | 1989 | 2815583 |
| structural and functional analysis of long terminal repeats of suncus murinus mammary tumor virus. | a 2.7-kilobase (kb) cdna sequence complementary to suncus murinus mammary tumor virus (sm-mtv) genomic rna [corrected] was prepared using purified virions produced by the sm-mt cell line, which had been established from a spontaneous mammary tumor of s. murinus. it was found, by using this cdna in southern hybridization experiments, that sm-mtv was endogenous to this animal and that some 50 copies of endogenous provirus were present per haploid cellular genome. in addition, a proviral sm-mtv dna ... | 1988 | 2831384 |
| [presence of antibodies specifically reacting with structural proteins of the mammary cancer virus among antibodies found in circulating immune complexes in patients with breast cancer]. | circulating immune complexes were precipitated from breast cancer patients' sera using 2.5% polyethylene glycol. cic isolated from 70 ml of sera from 15 patients were dissociated and immunoglobulin-containing fraction was prepared by chromatography on sephadex g-200 column. the fraction contained igg specific for mumtv structural proteins, as revealed by elisa. cic preparations from 22 sera of breast cancer patients were digested with pepsin; fab' fragment preparations were also analysed by elis ... | 1988 | 2833956 |