Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| a defined subgenomic fragment of in vitro synthesized moloney sarcoma virus dna can induce cell transformation upon transfection. | the longest dna molecules synthesized by endogenous reverse transcription in detergent-permeabilized moloney murine sarcoma virus (mo-msv) virions (clone g8-124) are double-stranded dna molecules of 5,8 kilobase pairs (kbp). this dna species has been purified by sedimentation of total in vitro synthesized mo-msv dna through neutral sucrose gradients. a physical map of the positions of the cleavage sites for a series of restriction endonucleases has been derived for this 5.8 kbp dna. mo-msv dna s ... | 1979 | 84715 |
| inhibition of murine sarcoma virus-induced foci formation by cytidine analogues and other drugs chemotherapeutically effective in human malignancies. | the present report describes an in vitro culture system using the kirsten murine sarcoma virus transformation focus assay to evaluate the antiviral activities of 12 commonly used chemotherapeutically effective drugs. since these drugs are cytotoxic, the plating efficiencies of the cells treated were monitored simultaneously. using this procedure, adriamycin, daunorubicin, bleomycin camptothecin, mithramycin, hydroxyurea, 5-fluorouracil, thioguanine, 9-beta-d-arabinofuranosyladenine, 1-beta-d-ara ... | 1979 | 88425 |
| inhibition of spontaneous transformation of rat embryo cells releasing endogenous type c virus by virus-specific antiserum. | noninbred sprague-dawley rat embryo cell clones predictably undergo transformation after 20-30 in vitro passages following spontaneous release of endogenous rat leukemia virus (ralv). in the presence of ralv-specific antiserum, virus production and infectivity were reduced and transformation was delayed from 6 to 25 weeks. transformation was not associated with an increased expression of kirsten murine sarcoma virus-related src gene rna. | 1979 | 89211 |
| analysis of proteins of mouse sarcoma pseudotype viruses: type-specific radioimmunoassay for ecotropic virus p30's. | murine sarcoma virus pseudotypes were prepared by infection of nonproducer cells (a1-2), which were transformed by the gazdar strain of mouse sarcoma virus, with gross (n-tropic), wn1802b (b-tropic), or moloney (nb-tropic) viruses. the respective host range pseudotype sarcoma viruses were defined by the titration characteristics on cells with the appropriate fv-1 genotype. proteins from virus progeny were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. bands present in bot ... | 1979 | 90164 |
| [biochemical characteristics of a calf leukemia virus in chronically infected cells]. | studied were the conditions of cultivation of flk cells chronically infected with a calf leucosis virus. the gradient values of density were compared to those of the murine sarcoma virus--1.14--1.15 vs, 1.17--1.18/cm3. established were the parameters of the reverse transcriptase reaction for the calf leukosis virus (magnesium-dependent reverse transcriptase). data showed that the calf leucosis virus may not resolutely be referred either to the b- or the the c-type of retroviruses. | 1979 | 92095 |
| suramin: a potent inhibitor of the reverse transcriptase of rna tumor viruses. | suramin--a well-known antitrypanosomal agent--was found to exert a strong inhibitory effect on the rna-directed dna polymerase (reverse transcriptase) activity of several oncornaviruses such as moloney murine leukemia virus, murine rauscher leukemia viruses, moloney murine sarcoma virus and avian myeloblastosis virus. inhibition of enzyme activity was obtained with both endogenous viral rna and (a)n . oligo(dt) as the template-primer. suramin effected a 50% inhibition of the reverse transcriptas ... | 1979 | 92362 |
| suppressor t cells regulate the cytolytic t lymphocyte response to syngeneic tumors induced by murine sarcoma virus (msv) in the mouse. | studies were designed to analyze the immune activities of spleen cells from mice previously injected with murine sarcoma virus (msv) and undergoing the processes of msv tumor growth and rejection. fractionation of msv-primed spleen cells according to cell size by velocity sedimentation at unit gravity showed that msv-specific cytolytic t lymphocytes (ctl) generated in vivo underwent an apparent transition in size from large to small cells as the tumor regressed. the majority of ctl precursors, h ... | 1979 | 156765 |
| detection of cellular immunity to murine sarcoma virus-induced tumors by leukocyte adherence inhibition. | 1979 | 214608 | |
| significance of the proline assay in the study of anti-msv cell-mediated immune reactions. | the cytolysis of 3h-proline-labelled tumour cells growing in monolayer by syngeneic immune lymphocytes has been studied in the murine sarcoma virus (msv) system. results show that the proline assay (pa) is a convenient way to reveal the activity of cytolytic t lymphocytes against fmr-like antigens. using the same effector and target cells, the classical chromium-release test (crt) fails to reveal any cytolytic activity, and the visual microcytotoxicity assay as well as several derived isotopic m ... | 1979 | 215185 |
| immunofluorescence on avian sarcoma virus-transformed cells: localization of the src gene product. | the localization of the avian sarcoma virus src gene product (termed p60src) was examined by indirect immunofluorescence in cells transformed by the schmidt-ruppin strain of rous sarcoma virus, subgroup d (sr-rsv-d). antiserum to p60src was obtained from rabbits bearing sr-rsv-d-induced tumors, and immunofluorescence was performed on chicken embryo fibroblasts (cef) transformed with sr-rsv-d, as well as normal rat kidney (nrk) cells transformed by the same virus (termed sr-rk cells). both aceton ... | 1979 | 217542 |
| the kinetic dissection of transport from metabolic trapping during substrate uptake by intact cells. uridine uptake by quiescent and serum-activated nil 8 hamster cells and their murine sarcoma virus-transformed counterparts. | 1. we present a theoretical analysis of the tandem processes of transport and metabolic trapping which together constitute uptake of a substrate by intact cells. 2. transport is assumed to occur by means of a simple carrier here analysed in its general form. trapping is assumed to occur by a simple enzymic reaction. 3. we show how to obtain the separate parameters of the steps by analysing uptake data over a range of uptake times and substrate concentrations. 4. we present uptake data for uridin ... | 1979 | 218628 |
| induction of lytic plaques by murine leukemia virus in murine sarcoma virus-transformed nonproducer mouse cells persistently infected with mouse hepatitis virus mhv-s. | kirsten murine sarcoma virus-transformed, nonproducer balb3t3 (k-balb) cells were persistently infected with mouse hepatitis virus, mhv-s. the cultures developed plaques after infection with murine leukemia viruses. if the murine leukemia virus-infected cultures were further submitted to the uv-xc assay, comparable numbers of xc plaques were obtained. the sensitivity to murine leukemia viruses, as determined by the uv-xc assay, was higher in mhv-s-infected cells as compared to uninfected k-balb ... | 1979 | 218897 |
| rescue and transmission of a replication-defective variant of moloney murine leukemia virus. | we have described a clone of mouse cells, termed "8a," which appears to be infected with a replication-defective variant of moloney murine leukemia virus (mulv) (rein et al., j. virol. 25:146-156, 1978). clone 8a cells release virus particles which do not form plaques in the standard xc test. however, approximately 10(2) particles per ml of clone 8a supernatant do form plaques in a modified xc test (the "complementation plaque assay"), in which the assay cells are coinfected with the xc-negative ... | 1979 | 219244 |
| cell-mediated immunity to antigens associated with murine sarcoma virus-induced tumors: augmentation of cytolytic t lymphocyte activity by successive specific and nonspecific stimulation in vitro. | it has been shown previously that lymphoid cells from mice which have rejected a tumor induced by the moloney sarcoma virus-leukemia virus (msv-mlv) complex develop high levels of specific h-2-restricted cytolytic t lymphocyte (ctl) activity after in vitro stimulation with syngeneic, irradiated mlv-induced lymphoma cells in mixed leukocyte-tumor cell cultures (mltc). attempts to further increase lytic activity by restimulating long-term mltc cells with syngeneic, irradiated lymphoma cells have m ... | 1979 | 221224 |
| unstable resistance of g mouse fibroblasts to ecotropic murine leukemia virus infection. | g mouse cells were resistant to n- and nb-tropic friend leukemia viruses and to b-tropic wn 1802b. though the cells were resistant to focus formation by the moloney isolate of murine sarcoma virus, they were relatively sensitive to helper component murine leukemia virus. to amphotropic murine leukemia virus and to focus formation by amphotropic murine sarcoma virus, g mouse cells were fully permissive. when the cell lines were established starting from the individual embryos, most cell lines wer ... | 1979 | 221667 |
| detection of a transformation-related antigen in chemically induced sarcomas and other transformed cells of the mouse. | antisera prepared against balb/c meth a sarcoma in syngeneic or compatible f1 mice recognize a protein with an apparent molecular weight of 53,000 in extracts of [35s]methionine-labeled transformed balb/c cells. this component, designated p53, was not detected in normal adult mouse fibroblasts, lymphoid cells, or hematopoietic cells or in mouse embryo cells or 3t3 cells. an extensive variety of antisera, including alloantisera and heterologous antisera directed against structural antigens of mur ... | 1979 | 221923 |
| a murine sarcoma virus-associated protein kinase: interaction with actin and microtubular protein. | a low molecular weight (lmw) protein phosphokinase enzyme that binds to actin has been isolated from murine sarcoma virions; this kinase activity is not present in nontransforming murine leukemia viruses. sephadex g-75 gel filtration and affinity chromatography on actin-sepharose conjugates allow a significant level of purification of this enzyme. the enzyme associates with microtubular proteins and inhibits the in vitro polymerization of microtubules. this study represents the first isolation o ... | 1979 | 222479 |
| cycloheximide-dependent reversion of human cells transformed by msv and chemical carcinogen. | the protein synthesis inhibitor cycloheximide, at a concentration of 0.08 microgram per milliliter, induced flat morphology within 24 to 48 hours and low saturation density in human osteosarcoma cells transformed by kirsten murine sarcoma virus (ki-msv) or n-methyl-n' nitro-n-nitrosoguanidine. removal of the protein synthesis inhibitor caused both transformed cells to revert to the transformed phenotype. the demonstration of cell-surface antigens, cross-reacted with antiserums induced by extract ... | 1979 | 223242 |
| murine sarcoma viruses block corticosteroid-induced differentiation of bone marrow preadipocytes associated with long-term in vitro hemopoiesis. | 1979 | 223284 | |
| identification of a sarcoma virus-coded phosphoprotein in nonproducer cells transformed by kirsten or harvey murine sarcoma virus. | a similar protein of 21,000 mw (p21) coded for by harvey or kirsten murine sarcoma virus has been identified in nonproducer cells transformed by these two viruses. antisera prepared from rats bearing tumors induced by syngeneic transplantation of nrk cells transformed by harvey murine sarcoma virus (ha-musv) specifically precipitated the ha-musv p21 from a nonproducer balb/c mouse cell and a nonproducer dog cell transformed by ha-musv. the same antisera also precipitated a similar protein, ki-mu ... | 1979 | 223311 |
| establishment of cell lines from the wild rodent millardia meltada and tests for endogenous virus. | four cell lines were established from the wild rodent, millardia meltada; an untransformed cell line (mm-d), a non-producer (np) cell line transformed with murine sarcoma virus (mm-cl4), and sv40-transformed cell lines (mm-8 mm-663). mm-d is epithelioid and contact-inhibited, whereas mm-cl4, mm-8, and mm-663 are fibroblastic and grow piling up. no endogenous virus was induced in millardia cell lines by a long-term culture with various inducers. millardia cell dna has no nucleotide sequence homol ... | 1979 | 223935 |
| enhancement by asbestos of oncogenesis by moloney murine sarcoma virus in cba mice. | five micrograms of finely ground crocidolite asbestos (uicc standard sample) were injected intraperitoneally into 3-week-old cba mice, together with 10(5) ffu of moloney murine sarcoma virus. altogether 44 out of 61 mice (72.1%) so treated developed palpable intraperitoneal tumours, and half of these died of such tumours within 100 days. the same amount of quartz and carbon similarly administered gave lower tumour incidences, namely, 19.4% (3.2% fatal) and 11.9% (1.5% fatal) respectively. only 1 ... | 1979 | 223995 |
| p21 of kirsten murine sarcoma virus is thermolabile in a viral mutant temperature sensitive for the maintenance of transformation. | we have recently described an intracellular protein, p21, in nonproducer cells transformed by either the kirsten (ki-msv) or harvey (ha-msv) strain of murine sarcoma virus (shih et al., virology, in press). the p21 is phosphorylated and has been shown to be coded for by either ki-msv or ha-msv. in this report, we compare the thermal stability of the newly synthesized [35s]methionine-labeled p21 in cells transformed by the wild-type ki-msv or by a mutant of ki-msv (ts 371) which is temperature se ... | 1979 | 225570 |
| orthotopic bone induction at sites of moloney murine sarcoma virus inoculation in mice. | moloney murine sarcoma virus (m-msv) induces at the site of inoculation in newborn and adult mice and rats various types of sarcoma, including osteosarcoma. the induced tumours are fatal in newborn, whereas sarcomas developed in adult animals regress spontaneously. the regression is mediated mainly by a cellular response. we have now demonstrated that the presence of sarcomas induced by m-msv is a powerful stimulus for periosteal osteogenesis around tumour masses. orthotopically induced osteogen ... | 1979 | 225678 |
| cytolytic activity of macrophages isolated from primary murine sarcoma virus (msv)-induced tumors. | macrophages isolated from regressing or progressing tumors induced by murine sarcoma virus (msv) were tested for cytolytic activity in a 18-h 51cr release assay. macrophages from the tumors of mice injected 14 days earlier with stocks of msv-producing regressor or progressor tumors had comparable levels of cytotoxicity. however, macrophages from the progressively growing tumors, 50--65 days after the inoculation with the progressor virus, had lower levels of cytotoxicity than those from the regr ... | 1979 | 226482 |
| thermolabile protein kinase molecules in a temperature-sensitive murine sarcoma virus pseudotype. | murine sarcoma virus-associated protein kinases that bind to actin have been purified by affinity chromatography on actin coupled to sepharose. heat inactivation studies showed the presence of thermolabile enzyme activity in pseudotypes containing a temperature-sensitivity mutant of murine sarcoma virus (msv) but not in two independent wild-type msv pseudotypes. studies with sephadex g-75 column fractions showed that a low molecular weight form, approximately 15,000, is the major thermolabile ki ... | 1979 | 226971 |
| a candidate rat-specific gene product of the kirsten murine sarcoma virus. | 1979 | 227164 | |
| loss of proviral dna sequences in a revertant of kirsten sarcoma virus-transformed murine fibroblasts. | a previously described revertant cell line (k-balb sr1212), derived as a single cell clone from a clonal line of murine fibroblasts (k-balb) transformed by a nonproductive infection with the kirsten strain of murine sarcoma virus, has normal morphology and growth kinetics and, unlike the transformed parent cell line, lacks a sarcoma virus that can be rescued. we report here that this reversion correlates with low to undetectable levels of expression of cellular ki-msv-specific rna and a reductio ... | 1979 | 227995 |
| guanine nucleotide-binding activity as an assay for src protein of rat-derived murine sarcoma viruses. | we have recently identified a 21,000-dalton protein, p21, coded for by kirsten or harvey murine sarcoma virus. on the basis of the results obtained with the p21 of a mutant of kirsten sarcoma virus, temperature sensitive for the maintenance of transformation, we concluded that the p21 was required for the maintenance of transformation induced by either virus. we report herein that when extracts from cells transformed by kirsten or harvey sarcoma virus are incubated with [(3)h]gdp or [alpha-(32)p ... | 1979 | 228288 |
| localization of the asv src gene product to the plasma membrane of transformed cells by electron microscopic immunocytochemistry. | the cellular location of the src gene product (p60src) of the schmidt-ruppin strain of avian sarcoma virus has been determined by electron microscopic immunocytochemistry in schmidt-ruppin asv-transformed nrk cells, and the amount of the protein in different regions of the cell has been quantified. the protein is concentrated on the inner surface of the plasma membrane, particularly under ruffles, and it is highly concentrated on the inner surface of the membrane near junctions connecting adjace ... | 1979 | 228858 |
| in vitro induction of t-lymphocyte-mediated cytotoxicity by infectious murine type c oncornaviruses. | we have developed a system to induce oncornavirus-specific secondary cytotoxic response in vitro. when moloney strain of murine sarcoma virus-immune spleen cells were cultivated with purified infectious moloney murine leukemia virus (m-mulv) or with supernates of tissue culture cells containing infectious virus, a virus-specific secondary cytotoxic response directed against type-specific determinant(s) of m-mulv was generated in vitro, as determined by a 4-h 51cr-release assay. the effector cell ... | 1979 | 229187 |
| heteroduplex analysis of the sequence relationships between the genomes of kirsten and harvey sarcoma viruses, their respective parental murine leukemia viruses, and the rat endogenous 30s rna. | the sequence relations between kirsten murine sarcoma virus (ki-sv), harvey murine sarcoma virus (ha-sv), and a rat endogenous 30s rna were studied by electron microscope heteroduplex analysis. the sequence relationships between the sarcoma viruses and their respective parental murine leukemia viruses (kirsten and moloney murine leukemia viruses), as well as between the two murine leukemia viruses, were also studied. the only observed nonhomology feature of the kirsten murine leukemia virus/molo ... | 1979 | 229250 |
| comparative study of different isolates of murine sarcoma virus. | the rna genomes of a variety of murine sarcoma viruses (msv) were compared by heteroduplex analysis. these viruses included the moloney-derived isolates 124-msv, m1-msv, m3-msv, ht1-msv, and np-msv and also two independent isolates, gazdar msv and 1712-msv. all of these viral genomes exhibited the acquired cellular sequences previously identified in 3124-msv and thought to be responsible for transformation and sarcomagenesis. the location of the acquired cellular sequences within the envelope ge ... | 1979 | 229256 |
| heteroduplex analysis of the rna of clone 3 moloney murine sarcoma virus. | heteroduplex analysis of the rna isolated from purified virions of clone 3 moloney murine sarcoma virus (m-msv) hybridized to cdna's from moloney murine leukemia virus (m-mlv) and clone 124 m-msv shows that the main physical component of clone 3 rna is missing all or most of the 1.5-kilobase (kb) clone 124 m-msv specific sequence denoted beta s (s. hu et al. cell 10:469--477, 1977). this sequence is either deleted in clone 3 rna or substituted by a very short (0.3-kilobase) sequence. in other re ... | 1979 | 229257 |
| cell cycle-dependent chronic infection of human cytomegalovirus in human osteogenic sarcoma cells. | human osteogenic sarcoma cells transformed by murine sarcoma virus (r970) showed restricted growth of human cytomegalovirus (hcmv). virus was attached to the same extent as in human fibroblasts. hcmv growth was blocked at early stages after virus penetration. splitting of infected r970 cultures resulted in infection of all cells. in experiments using synchronized r970 cells it was found that factor(s) associated with the s-phase of the cell cycle might be necessary for establishment of the infec ... | 1979 | 230311 |
| supplemental arginine increases thymic cellularity in normal and murine sarcoma virus-inoculated mice and increases the resistance to murine sarcoma virus tumor. | arginine supplements were given to 6 week old cba mice beginning 3 days prior to inoculation with a murine sarcoma virus, the moloney sarcoma virus (msv). although the basal diet contained 1.8% arginine and was therefore not arginine-deficient, supplementation of the diet and the drinking water with 0.5% arginine hcl reduced tumor incidence, lengthened the latency period, decreased tumor size, and hastened tumor regression. arginine also increased thymic weight and cellularity in normal and in m ... | 1979 | 231121 |
| inhibition of murine sarcoma virus induced transformation in an adenovirus -- nrk system. | cell transformation induced by murine sarcoma virus (msv-m) is significantly inhibited (80--90%) in a clonal line of normal rat kidney (nrk) cells when they are infected with rat cell passaged adenovirus 12 (r-ad12). no inhibition is seen when r-ad12 is added simultaneously with, or 1 1/2 or 24 hr after, msv-m infection, suggesting that inhibition occurs most probably intracellularly. there is also a direct correlation between the extent of focus formation and the concentration of r-ad12 used. c ... | 1979 | 231569 |
| decrese of collagen biosynthesis ability of swiss 3t3 cells transformed with the murine sarcoma virus (msv). | 1979 | 232424 | |
| functional heterogeneity and t cell-dependent activation of macrophages from murine sarcoma virus (msv)-induced tumors. | in studies on the functional activity of macrophages isolated from murine sarcoma virus (msv)-induced tumors, we have found that these cells may suppress immune responses as well as act as effector cells against the tumor. previously, we reported that macrophages from the tumor could inhibit the antitumor response by suppressing proliferation-dependent immune functions. here, we demonstrate that macrophages can also suppress the production of migration inhibition factor (mif) and macrophage acti ... | 1979 | 232622 |
| "sarc" sequence transcription in moloney sarcoma virus-transformed nonproducer cell lines. | (3)h-labeled complementary dna(sarc), complementary to the murine sarcoma virus (msv)-specific portion of the moloney msv (m-msv) genome, was prepared. m-msv-specific rna was then quantitated in the cytoplasm of several m-msv-transformed, non-virus-producing, clonal nih 3t3 cell lines. these lines, designated 71 n clones 5, 6, and 3, have been characterized previously by the degree to which they exhibit transformation properties and transcribe moloney murine leukemia virus-related rna (s. salzbe ... | 1979 | 430602 |
| enhancement of experimental tumors in mice by treatment with concanavalin a. | weanling balb/c mice given injections of 300 micrograms concanavalin a (con a) prior to and at frequent intervals after challenge with moloney murine sarcoma virus (m-musv), 3-methylcholanthrene (mca), or tepc-15 plasmacytoma cells showed an enhancement of tumor induction or development. with the m-musv and mca systems, this enhancement was evidenced by larger tumors and, in the mca system, by more devastating tumors. regression of the m-musv-induced tumors was more prolonged in con a-treated mi ... | 1979 | 480379 |
| prevention of transplantable tumors by adoptive transfer of spleen cells from immunized rats. | fischer 344 rats were specifically hyperimmunized with allogeneic, nonvirus-producing [kirsten murine sarcoma virus (kimsv)] or syngeneic, virus-producing [kimsv (rasheed)] rat tumors. spleen cells taken from these rats adoptively transferred protection against a 100 to 1,000 x rat tumor dose50 cell challenge with several different transplantable rat tumors. protection was obtained with spleen cells after removal of adherent cells and macrophages but not peritoneal cells. the spleen cells were n ... | 1979 | 501086 |
| the transforming gene of moloney murine sarcoma virus. | a cleavage map of the moloney murine sarcoma viral dna was constructed and compared with that of a spontaneously occurring deletion mutant. by restriction enzyme analysis, it was shown that a region encompassing over 40% of the viral information was not essential for transformation or rescue of the deletion mutant. the transforming region was further localised by analysis of the transforming activity in tissue culture of isolated restriction fragments of linear duoble-stranded sarcoma viral dna. ... | 1979 | 503218 |
| immunochemical characterization of tumor-associated surface antigens on a moloney leukemia virus-lymphoma, mbl-2. | tumor-associated surface antigens (tasa) on a moloney leukemia virus (m-mulv)-induced lymphoma, mbl-2, in c57bl/6 mice (b6) were characterized. the surface proteins of mbl-2 cells were selectively radioiodinated and then extracted by nonidet p40. the solubilized materials were then reacted with a variety of antisera: monospecific antisera to murine leukemia viral proteins (anti-gp69/71, anti-p30, anti-p15, anti-p12 and anti-p10), sera from b6 which regressed murine sarcoma tumors induced by muri ... | 1979 | 528073 |
| prevention of spontaneous leukemia in mice by oncornavirus immunization. | c57l, nih, and swr mice were immunized with inactivated gross leukemia virus (glv) and then mated with akr males. their f1 offspring were then immunized with the murine sarcoma virus pseudotype of glv, msv(glv). the concentrations of infectious ecotropic akr virus in tail extracts of immunized mice were 100- to 1,000-fold lower than in non-immunized controls when tested at 30--40 days of age. although viral titers increased slightly with time, the titers remained at least one log10 lower in the ... | 1979 | 216644 |
| radiation induction of endogenous type c virus from mouse cells transformed in vitro by murine sarcoma virus. | cell lines from akr and balb/c mouse embryos were compared for their sensitivity to x-ray induction of endogenous type c virus. k-balb cells, a balb/3t3 cell line nonproductively transformed by kirsten murine sarcoma virus, were found to be sensitive to x-irradiation. at a dose as low as 50 r, x-rays induced virus expression in k-balb cells, and the induction frequency increased with increasing dose of x-rays up to 400 r. among two classes of inducible endogenous viruses carried by k-balb cells, ... | 1979 | 216834 |
| phenotypically distinct target cells for murine sarcoma virus and murine leukemia virus marrow transformation in vitro. | an in vitro hematopoietic microenvironment was established from explained fragments of bone marrow from adult noninbred nih swiss mice with the use of corticosteroid-reconstituted horse serum. infection with kirsten murine sarcoma virus (ki-musv) with either a rauscher murine leukemia virus (r-mulv) or balb:virus-1 helper virus coat reduced proliferation of granulocytic and pluripotent hematopoietic stem cells and produced neoplastic transformation of both macrophages and preadipocytes in the ad ... | 1979 | 216835 |
| suppression of lymphokine production by macrophages infiltrating murine virus-induced tumors. | immune spleen cells from mice injected with murine sarcoma virus (msv) can produce migration inhibition factor (mif) in vitro after stimulation with intact tumor cells. we have now found that this effector function can be regulated by suppressor macrophages present in the tumor. the cells from the tumor (cft) exert a strong suppressive effect even after treatment with anti-thy 1.2 plus complement but lose this capacity if adherent or phagocytic cells are removed, suggesting that the macrophage i ... | 1979 | 314424 |
| in vitro studies of cell-mediated immunity to moloney murine leukemia virus and moloney leukemia-associated surface antigens. | cell-mediated immunity to moloney murine leukemia virus (m-mulv) and to tumor-associated surface antigens of leukemia cells induced by the virus was studied with an in vitro migration inhibition factor assay. spleen cells of c57bl/6n mice at day 14 following inoculation with moloney murine sarcoma virus, produced migration inhibition factor in response to m-mulv. the moloney murine sarcoma virus-immune spleen cells, however, did not respond to other murine type c viruses, to akr and rauscher vir ... | 1979 | 387218 |
| molecular cloning of moloney murine sarcoma virus: arrangement of virus-related sequences within the normal mouse genome. | the unintegrated circular dna form of moloney murine sarcoma virus (msv) has been cloned in bacteriophage lambda. discrete deletions in the viral genome were shown to occur during propagation of recombinant phage in escherichia coli. heteroduplex and restriction enzyme analyses indicated the deletion of tandemly repeated sequences within certain of the cloned msv dna inserts. cloned msv dna was used to prepare a probe composed of its acquired cellular (src) sequences, shown previously to be nece ... | 1979 | 392518 |
| moloney murine sarcoma virions synthesize full-genome-length double-stranded dna in vitro. | moloney murine sarcoma virus (msv) virions incubated under optimal conditions were shown to support extensive synthesis of double-stranded dna. the major product, a 5950-base-pair (6-kilobase-pair dna) double-stranded dna, was characterized by cleavage with restriction endonucleases and shown to contain a 600-nucleotide-long direct repeat at both ends of the msv genome. linear dna molecules made in vivo shortly after infection were compared to the linear double-stranded dna synthesized in vitro. ... | 1979 | 291003 |
| protein composition of a defective murine sarcoma virus particle possessing the enveloped type-a morphology. | 1979 | 227155 | |
| pleiotropic phenotype of cultured murine cells resistant to maytansine, vincristine, colchicine, and adriamycin. | a noncloned subline of 3t3fl cells was developed that was resistant to the toxicity of the ansamycin alkaloid maytansine. culture of 3t3fl cells with serially increasing concentrations of maytansine resulted in a cell line resistant to maytansine at concentrations 118-fold higher than concentrations cytotoxic for parental cells. resistant cells (3t3r) exhibited cross-resistance to colchicine, vincristine, adriamycin, and, to a lesser extent, cytochalasin b. studies of binding and uptake of triti ... | 1979 | 224236 |
| tumors induced by murine sarcoma virus contain precursor cells capable of generating tumor-specific cytolytic t lymphocytes. | leukocyte fractions extracted from the tumor mass and the lymphoid organs of c57bl/6 (b6) mice carrying murine sarcoma virus-induced tumors contained primed cytolytic t-lymphocyte (ctl) precursor cells, in addition to active cytotoxic t cells. these leukocyte fractions gave a secondary response when stimulated in vitro with syngeneic tumor cells, generating large numbers of specific ctl. the activity of these ctl (h-2b) was apparently h-2-restricted, because it was ineffective on tumor targets b ... | 1979 | 221614 |
| cytolytic and cytostatic anti-tumor activities of macrophages from mice injected with murine sarcoma virus. | 1979 | 759378 | |
| cytochalasin b-induced multinucleation of murine sarcoma virus-transformed cells. inhibition by sodium butyrate. | 1979 | 215423 | |
| transformation by cloned harvey murine sarcoma virus dna: efficiency increased by long terminal repeat dna. | the coding sequences for the transforming (src) protein (p21) of harvey murine sarcoma virus have been localized to a 1.3 kilobase pair segment near the 5' end of the viral genome. ligation of the viral terminal repeat dna to the left end of the src region dna markedly enhanced the low transforming efficiency of the src region dna. | 1980 | 6254153 |
| virus rna species in kirsten murine sarcoma virus-transformed mink cells. | the nuclear and cytoplasmic rnas from kirsten murine sarcoma virus (kimusv)-transformed non-producer mink cells were studied for the species of virus-specific rna by fractionation in agarose gels, transfer to diazotized aminophenylthioether paper and hybridization to complementary dna probe. in both nuclei and cytoplasm, only genome-length kimusv-specific rna was detected. no subgenomic virus rna species was detected in poly(a+) or poly(a-) rna fractions. the same observations were made in kimus ... | 1980 | 6257834 |
| systemic and in situ natural killer activity in c57bl/6n and cba/n mice bearing murine sarcoma virus-induced regressor tumors. | both systemic and in situ natural killer (nk) activity was assessed in young and old c57bl/6n and cba/n mice bearing primary murine sarcoma virus-induced tumors. splenic nk activity was depressed in tumor-bearing mice relative to normal age-matched controls. in situ nk activity was detected in young mice, and the level paralleled that found in the spleens of the same mice. in older mice, in situ nk activity was not detected. furthermore, the depressed levels of activity in the spleens of tumor-b ... | 1980 | 6253708 |
| identification of a normal vertebrate cell protein related to the p21 src of harvey murine sarcoma virus. | 1980 | 6254252 | |
| guanine nucleotide-binding and autophosphorylating activities associated with the p21src protein of harvey murine sarcoma virus. | the purified p21src protein of harvey sarcoma virus shows a guanine nucleotide-binding activity and, in addition, at elevated temperature an autophosphorylating activity at a threonine residue using as phosphoryl donor gtp or dgtp but not atp or datp. these biochemical activities are unique among those associated with transforming proteins of rna-containing or dna-containing tumour viruses. | 1980 | 6253810 |
| the translation products of moloney murine sarcoma virus-124 rna. | 1980 | 6251612 | |
| characterization of tumorigenic and metastatic properties of murine sarcoma virus-transformed nonproducer balb/3t3 cell lines. | 1980 | 6245299 | |
| antigenic specificity of the cytolytic t lymphocyte (ctl) response to murine sarcoma virus-induced tumors. ii. analysis of the clonal progeny of ctl precursors stimulated in vitro with syngeneic tumor cells. | 1980 | 6154076 | |
| suppression of the leukocyte adherence inhibition response to murine-sarcoma-virus-induced tumors by tumor-associated suppressor cells. | the tumor-specific leukocyte adherence inhibition (lai) response of lymphoid cells from c57b1/6 mice sensitized to a murine-sarcoma-virus (musv)-induced tumor was inhibited by adherent phagocytic spleen cells from mice with progressively growing rbl-5 tumors. both the direct lai response and the formation of the mediator of lai were sensitive to the suppressive activity of the progressor spleen macrophages. suppression of lai was not restricted by h-2 differences between the sensitized lymphocyt ... | 1980 | 6253859 |
| structure of murine sarcoma virus dna replicative intermediates synthesized in vitro. | moloney murine sarcoma virions synthesize discrete dna products in vitro which closely resemble those found in vivo shortly after infection. these in vitro products have been isolated by electrophoresis and mapped with restriction endonucleases. in addition to the full-genome-length 6-kilobase pair linear dna, a 5.4-kilobase pair circular dna molecule, an incomplete linear dna molecule, and a 600-base pair molecule were detected. the 6-kilobase pair dna contained a 600-base pair direct terminal ... | 1980 | 6245239 |
| moloney murine sarcoma virus oncogenesis in t-lymphocyte-deprived mice: biologic and immunologic studies. | 1980 | 6243378 | |
| leukocyte adherence inhibition response to murine sarcoma virus-induced tumors. i. cell requirements, specificity, lack of h-2 restriction, and role of antibody. | 1980 | 6154099 | |
| characterization of viral polyproteins in cells transformed and producing moloney murine sarcoma virus-124. | the viral proteins of moloney murine sarcoma virus-transformed mouse cells (g8-124), that overproduce the sarcoma virus relative to helper leukemia virus, were examined by immunoprecipitation, sizing by gel electrophoresis and peptide mapping. using antisera to the viral core proteins, a p10-deficient core polyprotein of 63 000 daltons (p63gag) was detected which was found to be a product of the musv-124 genome. helper virus proteins pr67gag, gpr85gag, pr200gag-pol, and gpr83env were also detect ... | 1980 | 6156703 |
| antigenic specificity of the cytolytic t lymphocyte response to murine sarcoma virus-induced tumors. iii. characterization of cytolytic t lymphocyte clones specific for moloney leukemia virus-associated cell surface antigens. | cytolytic t lymphocyte (ctl) clones specific for moloney leukemia virus (molv)-derived tumor cells were generated by placing limiting numbers of c57bl/6 responder cells into mixed leukocyte-tumor cell microcultures. under appropriate conditions (presence of stimulating tumor cells, accessory cells, and t cell growth factor), such cloned ctl could readily be expanded to provide large numbers of homogeneous, highly cytolytic ctl populations for further characterization. using four target-cell type ... | 1980 | 6159445 |
| interferon inhibits transformation by murine sarcoma viruses before integration of provirus. | neoplastic transformation by c-type retroviruses requires synthesis of a dna copy (the provirus) of the rna genome and its integration into the host cell dna. we have previously shown that interferon (ifn) can stably prevent transformation of murine fibroblasts by the kirsten strain of murine sarcoma virus (kimsv), a murine leukaemia virus (mlv). a series of cell clones (ifn clones), isolated in the presence of ifn (10(4) u ml-1) from cultures of nih-3t3 cells which had been treated with ifn, an ... | 1980 | 6159546 |
| t cell-mediated immunity to oncornavirus-induced tumors. i. ly phenotype of precursor and effector cytolytic t lymphocytes. | regression of tumor induced by murine sarcoma virus (msv) is accompanied by the formation of specific cytolytic t lymphocytes (ctl). selection of t-cells sets by ly phenotype determination allows separation of t sets involved in the cytolytic reaction. after msv inoculation we demonstrate that a) ly123+ cells contain precursors of ctl, b) direct cytolysis is mainly mediated by ly23 cells, 3) cytolytic memory is divisible into "early" memory, carried by ly23 cells, and "late" memory, which revert ... | 1980 | 6243332 |
| envelope properties of murine sarcoma virus-zero (msv-z). | 1980 | 6243828 | |
| biological and molecular biological characterization of the virus progeny from transformed clones musv-124 and musv-349: evidence for mulv-specific nucleotide sequences in the momusv size class of rna from momusv-124. | the genetic information of momusv-349 and momusv-124, two clones of productively transformed tb cells, was distributed between two size classes of rna (mol. wt. 2.9 x 10(6)) in the proportions of 5:1. some preparations of momusv-124 lacked the large rna. the virions produced by both clones also contained all the nucleotide sequences of moloney leukaemia virus and the ratio of musv:mulv produced by the two clones differed markedly. the distribution of the sequences specific for moloney murine leu ... | 1980 | 6245178 |
| in vitro production and titration assays of b-tropic retroviruses isolated from c57bl mouse tumors induced by radiation leukemia virus (radlv-rs): effect of dexamethasone. | the effect of dexamethasone (dxm) on the replication and titration assays of b-ecotropic radiation leukemia virus (radlv-rs) isolates was examined. the drug was shown to enhance in vitro virus release by otherwise low producer permissive cells. dxm also stimulated infectivity and focus formation in murine s+l--permissive cells and shortened the time-appearance of virus-induced foci. in contrast to foci observed in nontreated cultures, which are generally abortive and composed of only a few morph ... | 1980 | 6246028 |
| sarcoma growth factor (sgf): specific binding to epidermal growth factor (egf) membrane receptors. | cells transformed by murine sarcoma viruses (msv) produce and release into their tissue culture media several polypeptide growth stimulating factors. one of these has been partially purified using bio-gel p-60 column chromatography followed by deae-cellulose chromatography. this growth factor was assigned the name sarcoma growth factor (sgf), and is here shown to require the epidermal growth factor (egf) receptor in order to function as a growth factor. deae-cellulose chromatography yielded a pr ... | 1980 | 6246130 |
| molecular cloning of snyder-theilen feline leukemia and sarcoma viruses: comparative studies of feline sarcoma virus with its natural helper virus and with moloney murine sarcoma virus. | extrachromosomal dna obtained from mink cells acutely infected with the snyder-theilen (st) strain of feline sarcoma virus (feline leukemia virus) [fesv(felv)] was fractionated electrophoretically, and samples enriched for felv and fesv linear intermediates were digested with ecori and cloned in lambda phage. hybrid phages were isolated containing either fesv or felv dna "inserts" and were characterized by restriction enzyme analysis, r-looping with purified 26 to 32s viral rna, and heteroduplex ... | 1980 | 6246254 |
| in vitro production of immunosuppressive factors by murine sarcoma virus-transformed mouse fibroblasts. | murine sarcoma virus-transformed mouse fibroblasts produce potent immunosuppressive factors (isf) in vitro. the partially purified isf inhibited thymocyte proliferation induced by concanavalin a or phytohemagglutinin plus lymphocyte activating factor (interleukin 1), lipopolysaccharide-induced spleen cell proliferation, the in vitro splenic anti-sheep erythrocyte plaque-forming cell response, and the generation of alloantigen-specific cytotoxic t cells. the effect of isf on thymocyte proliferati ... | 1980 | 6246526 |
| localization of the src gene product of the harvey strain of msv to plasma membrane of transformed cells by electron microscopic immunocytochemistry. | using electron microscopic immunocytochemistry, we have investigated the intracellular location of the src protein (p21) in cells transformed by the harvey strain of murine sarcoma virus (ha-msv). antibodies to p21 were derived from tumor-bearing rats inoculated with ha-nrk cells. the distribution of p21 in intracellular sites in mdck dog cells transformed by ha-msv was examined and quantified using a recently developed immunocytochemical technique. more than 95% of p21 was localized to the inne ... | 1980 | 6247068 |
| double transformation of indian muntjac cells by avian and murine sarcoma viruses. | avian sarcoma virus-transformed indian muntjac cells, sr-mm-1, formed foci by murine sarcoma-xenotropic murine leukemia virus complex [msv(x-mulv)] superinfection. the response of sr-mm-1 and parental normal indian muntjac mm-2k cells to msv(x-mulv) infection was compared. focus formation by msv(x-mulv) followed two-hit kinetics in mm-2k, but one-hit kinetics in sr-mm-1 cells. msv(x-mulv)-infected sr-mm-1 cells formed larger colonies than uninfected sr-mm-1 cells in soft agar, while no colony wa ... | 1980 | 6247523 |
| factors affecting responses to murine oncogenic viral infections. | silica specifically kills macrophages in vitro, and in vivo has been used as a method of determining the possible immunological or other roles of macrophages in a number of viral infections. in experiments reported here, injection of 30 or 50 mg silica i.p. increased the severity of the oncogenic effects of the murine sarcoma virus (msv) and friend virus (fv) in balb/c mice. unlike herpes simplex and coxsackie b-3 infections, however, passive transfer of adult macrophages to suckling mice did no ... | 1980 | 6248095 |
| prostaglandin e1 binding and adenylate cyclase activation in normal and transformed fibroblasts. | the binding of [3h]prostaglandin e1 to membranes of clones of normal rat kidney fibroblasts (nrk cells) has been measured. cell lines that responded to prostaglandin e1, such as nrk and nrk transformed with schmitt-ruppin strain of rous sarcoma virus (sr-nrk cells), have a high affinity prostaglandin e1 binding site. murine-sarcoma-virus-transformed lines of nrk cells are unresponsive to prostaglandin e1 and have reduced prostaglandin e1 binding exposure of cells to prostaglandin e1 results both ... | 1980 | 6248120 |
| non-t-cell-mediated cytotoxicity in mice with tumors induced by moloney murine sarcoma virus (m-musv). ii. granulocyte-mediatd cytotoxicity against autochthonous target cells isolated from m-musv-induced tumors. | experiments were performed in a/sn and a/wysn mice to determine the specificity, organ distribution, and further characteristics of the small non-t-cells that infiltrate moloney murine sarcoma virus (m-musv)-induced tumors and are capable of killing the autochthonous m-musv-infected tumor target cells. continuous bovine serum albumin density gradient separation proved to be the most effective method of enriching the cytotoxic cells. increase in cytotoxic activity, measured by both the 51cr relea ... | 1980 | 6249952 |
| myeloproliferative virus, a cloned murine sarcoma virus with spleen focus-forming properties in adult mice. | myeloproliferative virus, derived from moloney sarcoma virus, causes erythroleukemia and myeloid leukemia in adult mice. this virus is also capable of fibroblast transformation in vitro. the virus consists of two separable biological entities which have been cloned. the helper virus component caused no visible changes in adult mice, whereas the defective virus induced both spleen focus formation and a large increase in erythroid precursor cells but retained the sarcoma virus property of transfor ... | 1980 | 6251235 |
| functional organization of the harvey murine sarcoma virus genome. | the comparative infectivity of harvey murine sarcoma virus (ha-musv) dna for nih 3t3 cells was determined for supercoiled ha-musv dna molecularly cloned in lambda phage and pbr322 at its unique ecori site (which is located near the middle of the 6-kilobase pair [kbp] unintegrated linear viral dna) and for two cloned subgenomic fragments: one was 3.8 kbp and lacked about 1 kbp from each side of the ecori site, and the second did not contain the 3 kbp of the unintegrated linear viral dna located o ... | 1980 | 6251279 |
| transforming growth factors: isolation of polypeptides from virally and chemically transformed cells by acid/ethanol extraction. | polypeptides characterized by their ability to confer a transformed phenotype on an untransformed indicator cell have been isolated directly from tumor cells growing both in culture and in the animal, by using an acid/ethanol extraction procedure. assay of these polypeptides is based on their ability to induce normal rat kidney fibroblasts to form colonies in soft agar. peptides from murine sarcoma virus-transformed mouse 3t3 cells grown in culture had the highest specific activity in this assay ... | 1980 | 6251462 |
| biological activity of cloned moloney sarcoma virus dna: terminally redundant sequences may enhance transformation efficiency. | we have measured the ability of cloned restriction fragments containing the whole and partial genomes of two strains of moloney murine sarcoma virus to induce cell transformation in dna transfection assays. the cloned intact ml and htl murine sarcoma virus proviruses transform with an efficiency of approximately 40,000-50,000 focus-forming units/pmol of proviral dna, and the majority of these transformed cells contain a rescuable viral genome. a cloned 2.1-kilobase-pair internal fragment of the ... | 1980 | 6251463 |
| isolation and partial characterization of a 55,000-dalton protein induced in cells transformed by the ml strain of moloney murine sarcoma virus. | 1980 | 6251602 | |
| organization of murine sarcoma virus genomes. | 1980 | 6253206 | |
| cellular origin of the transforming gene of moloney murine sarcoma virus. | 1980 | 6253207 | |
| characterization of virus-specified proteins present in nrk cells infected with a temperature-sensitive transformation mutant of moloney murine sarcoma virus. | 1980 | 6253209 | |
| kirsten murine sarcoma virus transformed cell lines and a spontaneously transformed rat cell-line produce transforming factors. | we have examined culture fluids from a variety of kirsten murine sarcoma virus (kimsv) transformed rat and mouse cells for the presence of factors which induce normal rat-1 cells to assume the transformed phenotype. all kimsv transformants produced transforming factor (tf). revertants of kimsv transformed rat or mouse failed to release tf as did normal rat or mouse cells. cells transformed by a temperature sensitive mutant of kimsv produced tf at the permissive temperature but not at the nonperm ... | 1980 | 6253509 |
| dual evolutionary origin for the rat genetic sequences of harvey murine sarcoma virus. | detailed restriction endonuclease maps were developed for harvey murine sarcoma virus (ha-musv) dna (clone h-1), molecularly closed at its unique ecori site in pbr322, for three nonoverlapping subgenomic hindiii clones which together span the entire h-1 clone and for a molecularly cloned dna copy of a portion of rat 30s rna (which represents the majority of the rat genetic sequences in ha-musv). molecular hybridization of the 30s clone to small restriction fragments of clone h-1 revealed a 0.9-t ... | 1980 | 6253666 |
| mapping of transforming region of the harvey murine sarcoma virus genome by using insertion-deletion mutants constructed in vitro. | circular dna intermediates of harvey murine sarcoma virus (ha-musv) have been cloned in lambda gtwes . lambda b and shown to be capable of transforming mouse nih 3t3 cells [hager, g. l., chang, e. h., chan, h. w., garon, c. f., israel, m. a., martin, m. a., scolnick, e. m. & lowy, d. r. (1979) j. virol. 31, 795-809]. by using the cloned ha-musv dna insert as a parental genome, we have constructed a series of insertion-deletion mutants by inserting an octomer containing the sal i linker sequence ... | 1980 | 6254037 |
| nucleotide sequence analysis of the transforming region and large terminal redundancies of moloney murine sarcoma virus. | the sequence of the transforming region of the moloney murine sarcoma virus genome has been determined by using molecularly cloned viral dna. this region, 3.6 to 5.8 kilobase pairs from the left end of the molecule, contains the entire cellular insertion (src) sequence as well as helper viral sequences including the large terminal repeat (ltr). on the viral rna strand, a long (1224 bases) open reading frame commenced to the left of the src-helper virus junction and terminated at a point 58 nucle ... | 1980 | 6254069 |
| transforming growth factors produced by certain human tumor cells: polypeptides that interact with epidermal growth factor receptors. | three different human tumor lines in culture, a rhabdomyosarcoma, a bronchogenic carcinoma and a metastatic melanoma, release proteins (transforming growth factors, tgfs) into the medium that confer the transformed phenotype on untransformed fibroblasts. these proteins are acid and heat-stable; produce profound morphologic changes in rat and human fibroblasts; and enable normal anchorage-dependent cells to grow in agar. removal of the transforming protein results in a reversion of cell phenotype ... | 1980 | 6254071 |
| multinucleation in the presence of cytochalasin b by rna tumor virus-transformed cells. | rna tumor virus-transformed cell cultures derived from rat, mouse, hamster, and mink were examined for their response to cytochalasin b (cb), and the expression of this marker was correlated with growth in soft agar and tumorigenicity in vivo. continuous cell lines transformed and chronically infected with moloney murine sarcoma-leukemia virus (m-msv-mulv) or kirsten murine sarcoma-leukemia virus were extensively multinucleated when treated with cb. similarly, nonproducer moloney murine sarcoma ... | 1980 | 6254645 |
| simian virus 40 and moloney-murine sarcoma virus infection of bona fide mouse epithelium. | moloney-murine sarcoma virus (moloney-msv) and simian virus 40 (sv40) were found to infect successfully pure cultures of epithelial cells established from mouse liver and mammary tissue. msv infection resulted in transient morphological foci with persistent production of infectious virus. sv40 infection produced detectable levels of virus-specific t antigen in the cells but morphological transformants were not observed. | 1980 | 6255079 |
| frequent site-specific deletion of coliphage lambda murine sarcoma virus recombinants and its use in the identification of a retrovirus integration site. | stocks of hybrid lambda phages carrying the complete integrated provirus of either m1 or ht1 moloney murine sarcoma virus, as well as flanking host sequences, frequently contain significant numbers of phages carrying a specific deletion. this deletion arises from a recombination event between the terminally repeated sequences in the provirus that deletes the unique moloney murine sarcoma virus sequences bracketed by the terminally repeated sequences. physical mapping has shown that the deletion ... | 1980 | 6255187 |
| lack of focus formation of s+l- mink cells by the ecotropic murine leukemia viral genome. | infection of mink s+l- cells with ecotropic murine leukemia virus, achieved by phenotypic mixing with xenotropic virus, did not result in the induction of transformed foci. also, clonal line of s+l- mink cells, chronically infected with ecotropic murine leukemia virus, which produce both the ecotropic virus and its murine sarcoma virus pseudotype are morphologically indistinguishable from normal s+l- mink cells. neutralizing antiserum added to s+l- mink cells inoculated with xenotropic virus 24 ... | 1980 | 6255204 |