Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| regulation of cell-mediated immunologic reactivity to moloney murine sarcoma virus-induced tumors. i. cell and serum activity detected by leukocyte adherence inhibition. | cell-mediated immunity and serum regulatory factors were studied in an in vitro system involving a spontaneously regressing, virus-induced tumor. inbred balb/c and cba mice were inoculated with moloney murine sarcoma virus and their peritoneal cells were tested for reactivity in leukocyte-adherence inhibition tests with extracts of syngeneic tumors. sera from inoculated mice were tested for their effect on this reactivity. at the optimal dilution, tumor extracts induced significant reactions wit ... | 1981 | 6264193 |
| three distinct genes in human dna related to the transforming genes of mammalian sarcoma retroviruses. | southern blot hybridization was used to identify human and other vertebrate dna sequences that were homologous to cloned dna fragments containing the oncogenic nucleic acid sequences of three different type c mammalian retroviruses (simian sarcoma virus, the snyder-theilen strain of feline sarcoma virus, and the harvey strain of murine sarcoma virus). each onc gene counterpart has a single genetic locus, which probably contains non-onc intervening sequences. the human dna sequences may represent ... | 1981 | 6264598 |
| enhancement of antibody activity to bovine leukemia virus by complement. | cocultivation of fetal lamb kidney cells infected with bovine leukemia virus (blv) and the cat cells containing murine sarcoma virus genome resulted in the rapid production of syncytia. this syncytia formation was inhibited by serum containing antibodies to glycoprotein antigen of blv. when rabbit complement was added to the antiserum for early syncytia inhibition (esi) test, a significant enhancement of esi activity of the antiserum was observed. this enhancement was associated with igg fractio ... | 1981 | 6264895 |
| transforming growth factor production by chemically transformed cells. | evidence is presented indicating that the chemically transformed akr-mca and c3h/mca-58 murine cell lines produce "transforming growth factor(s)" capable of inducing a transformed morphology and the ability to grow in soft agar in nontransformed, anchorage-dependent indicator cells. serum-free medium conditioned by exposure to the chemically transformed cells was chromatographed on a bio-gel p-60 column after dialysis and lyophilization. using the nontransformed mouse akr-2b cells as the indicat ... | 1981 | 6265069 |
| in vivo antigenic modification of tumor cells. iii. metastatic thymic lymphoma specifically infected by thymotropic retrovirus. | tissue distribution of radiation leukemia virus (radlv) was examined after its inoculation into normal c57bl/6j (b6) mice, b6 mice bearing a transplantable, non-virus-producing thymic lymphoma (rl12-np), and b6 mice bearing a transplanted non-virus producing, harvey murine sarcoma virus-transformed fibrosarcoma. virus expression was determined by competition radioimmunoassay for murine leukemia virus (mulv) p30 (predominant group-reactive antigen of mulv) and for radlv p12 (a highly type-specif ... | 1981 | 6265678 |
| the p21 src genes of harvey and kirsten sarcoma viruses originate from divergent members of a family of normal vertebrate genes. | the harvey and kirsten strains of murine sarcoma virus encode enzymatically and serologically related p21 src proteins which are required for virally mediated cellular transformation. the genes in each virus encoding p21 show such extensive divergence from each other that cloned probes from these genes detect distinct sets of cellular genes in the dna from several vertebrate species. these data suggest that cellular p21 sarc genes constitute a divergent family of vertebrate genes that can regula ... | 1981 | 6265801 |
| host range of murine sarcoma virus, its host modification and phenotypic mixing with endogenous virus. | the m(msv)ag-50 cells produce competent ecotropic sarcoma virus which is able to transform several rodent embryo cells and replicate in them. the expanded host range has shown that the virus acquired some host information which facilitate the transformation of heterologous cells. the transformed cells were xc positive and with transformed phenotype in vitro. the genome of mouse sarcoma virus from nonproducer rat liver cells could be rescued by xenotropic endogenous virus. the obtained virus has ... | 1981 | 6265817 |
| transforming growth factors (tgfs): properties and possible mechanisms of action. | transforming growth factors (tgfs) are growth-promoting polypeptides that cause phenotypic transformation and anchorage-independent growth of normal cells. they have been isolated from several human and animal carcinoma and sarcoma cells. one tgf is sarcoma growth factor (sgf) which is released by murine sarcoma virus-transformed cells. the tgfs interact with epidermal growth factor (egf) cell membrane receptors. tgfs are not detectable in culture fluids from cells which contain high numbers of ... | 1981 | 6267317 |
| analysis of two divergent rat genomic clones homologous to the transforming gene of harvey murine sarcoma virus. | harvey murine sarcoma virus (ha-musv) is a mouse-rat recombinant retrovirus that encodes a protein designated p21, required for virally induced transformation. using a radiolabeled dna fragment from the p21 coding region, we have detected homologous dna sequences in the normal dna of rats and of several other vertebrate species. moreover, many tested cells from these species contain low levels of a p21 protein that is highly related to viral 21. now we report two independent fragments from norma ... | 1981 | 6267583 |
| t lymphocyte tolerance and early appearance of virus-induced cell surface antigens in moloney-murine leukemia virus neonatally injected mice. | regression of moloney-murine sarcoma virus- (m-msv) induced sarcomas in normal adult mice is accompanied by generation of virus-specific cytotoxic t lymphocytes (ctl). however, when neonatal mice that were injected with moloney-murine leukemia virus (m-mulv carrier) were subsequently challenged as adults with m-msv, the sarcomas did not regress nor did they generate ctl. this failure to produce ctl cannot be ascribed to nonspecific immunodepressive effects or to suppressor cell generation since ... | 1981 | 6969741 |
| quantitation and clonal isolation of cytolytic t lymphocyte precursors selectively infiltrating murine sarcoma virus-induced tumors. | a limiting dilution mixed leukocyte-tumor cell microculture system was used to quantitate cytolytic t lymphocytes and their precursors (ctl-p), which infiltrate tumors induced by injection of moloney sarcoma-leukemia virus (msv-molv) complex into c57bl/6 mice. leukocyte populations obtained from tumors collected on day 10 after virus injection were found to contain significantly higher frequencies of operationally defined (tumor-specific) ctl-p than either peripheral blood leukocytes (pbl) or sp ... | 1981 | 6973602 |
| a selective temperature-sensitive defect in viral rna expression in cells infected with a ts transformation mutant of murine sarcoma virus. | 1981 | 7273137 | |
| distribution of in vitro-stimulated immune lymphocytes in mice bearing moloney murine sarcoma virus-induced primary tumor. | the distribution of in vitro-stimulated immune lymphocytes in tumor-bearing mice was studied. spleen cells from balb/c mice which had regressed moloney murine sarcoma virus (m-msv)-induced primary tumors, were sensitized in vitro by using moloney murine leukemia virus-induced balb/c lymphoma (lstra). lymphocytes obtained 6 days after stimulation were examined for cytotoxic activity against lstra cells, labeled with 51 cr or 99mtc, and inoculated into mice bearing msv-induced primary tumors. the ... | 1981 | 7274651 |
| virally induced periosteal osteogenesis in mice. | inoculation of moloney murine sarcoma virus (m-msv) into shank muscles of adult nmri mice resulted in localized sarcoma and periosteal membrane proliferation with subsequent periosteal bone formation. newly formed bone arose from outer surface of shank bones. two weeks after m-msv inoculation the width of bone cortex increased nearly 4 times. the spaces between newly formed bone ossicles were filled with bone marrow. in the later stages these bone marrow cavities were merged with medullar caviti ... | 1981 | 6783270 |
| in vivo antigenic modification of tumor cells. i. introduction of murine leukemia virus antigens on non-virus-producing murine sarcomas. | murine oncovirus antigens represent excellent targets for immune recognition, and virus-associated tumors are generally susceptible to various immunotherapy protocols. virus-negative tumors, however, are nonimmunogenic and refractory to immunologic control. therefore, the feasibility of the introduction of antigens onto non-virus-expressing tumors in situ in inbred c57bl/6j mice by systemic administration of nononcogenic murine retroviruses was investigated. two classes of murine fibrosarcomas w ... | 1981 | 6942181 |
| in vivo antigenic modification of tumor cells. ii. distribution of virus in sarcoma-bearing mice. | murine leukemia viruses were previously demonstrated to be able to infect efficiently non-virus-expressing tumors in vivo. in the present study the infectivity and tissue distribution of friend murine leukemia virus (f-mulv) in normal and tumor-bearing c57bl/6j (b6) mice were examined. two syngeneic fibrosarcoma-inducing cell lines were used: cells from a 3-methylcholanthrene-induced fibrosarcoma syngeneic to b6 mice (mca-fs) and cells from a harvey murine sarcoma virus-transformed, nonproducer ... | 1981 | 6942182 |
| ldhk, an unusual oxygen-sensitive lactate dehydrogenase expressed in human cancer. | an unusual isozyme of lactate dehydrogenase (ldh; l-lactate:nad+ oxidoreductase, ec 1.1.1.27), ldhk, has been described in cells transformed by the kirsten murine sarcoma virus (kimsv). this isozyme appears to contain one or more subunits encoded by the transforming gene of kimsv and is readily distinguished from other isozymes of ldh. specifically, it is more basic than other ldh isozymes, has an apparent subunit structure of (35,000)4(22,000)1, is essentially inactive if assayed under a normal ... | 1981 | 6942426 |
| sequence of events in the transformation process in cells infected with a temperature-sensitive transformation mutant of moloney murine sarcoma virus. | normal rat kidney cells infected with the temperature-sensitive transformation mutant of moloney murine sarcoma virus were used to study the biochemical and morphological changes that occur during transformation. the infected cells exhibited a normal morphology at the nonpermissive temperature (39 degrees c) and a transformed morphology at the permissive temperature (33 degrees c). a new viral protein was detected 2 hr after shift to the permissive temperature as a polyprotein with an estimated ... | 1981 | 6946495 |
| no activation of new initiation points for deoxyribonucleic acid replication in balb/c 3t3 cells transformed by kirsten sarcoma virus. | balb/c 3t3 cells were transformed by kirsten sarcoma virus, and five clones were isolated in soft agar. average replicon sizes of the transformed cell lines were estimated by the method of fiber-autoradiography (j. a. huberman and a. d. riggs, j. mol. biol.32:327-341, 1968) and found to be the same size as the nontransformed 3t3 cells, analyzed in parallel. the results indicate that, unlike simian virus 40 and epstein-barr virus, kirsten sarcoma virus does not activate new initiation points for ... | 1981 | 9279389 |
| harvey and kirsten sarcoma viruses promote the growth and differentiation of erythroid precursor cells in vitro. | harvey and kirsten murine sarcoma viruses have previously been shown to transform fibroblastic cells in culture, and type c virus pseudotypes of these viruses cause erythroleukemia in susceptible mice. we report a cell culture assay for quantitating the growth-promoting effect of harvey and kirsten viruses on erythroid cells. murine hemopoietic cells were infected in vitro with harvey or kirsten sarcoma virus, and then cultured in methylcellulose in the presence of relatively low concentrations ... | 1981 | 6276011 |
| migration of null lymphocytes to murine sarcoma virus-induced tumors. | 1981 | 6266725 | |
| induction of surface qa2 on lymphoid cells. | three tumor cell lines isolated from individual murine sarcoma virus-infected balb/cby (qa2-) mice were established. boms, ora i, and thorbly i were analyzed for the expression of qa2 and ly surface differentiation antigens. by cytofluorograf analysis and absorption techniques, all 3 cell lines were found to be qa2+, ly1-, ly2-. this cell surface phenotype suggests that immature lymphoid cells are uniquely susceptible to transformation by virus. anomalous appearance of qa2 on transformed lymphoi ... | 1981 | 7229374 |
| identification of unintegrated forms of kirsten murine sarcoma viral dna and restriction endonuclease cleavage map of linear dna. | we detected unintegrated linear 7.0-kilobase pair dna and covalently closed circular dna species in nih3t3 cells recently infected with kirsten murine sarcoma virus. using the linear dna, we constructed a restriction endonuclease cleavage map and compared it with the map of harvey murine sarcoma virus. the restriction endonuclease maps of two segments, one 1.2 kilobase pairs (smai site) to 3.7 kilobase pairs (hindiii site) from the right end (corresponding to the viral 3' side) and the other 0.5 ... | 1981 | 6264147 |
| structure and functions of the kirsten murine sarcoma virus genome: molecular cloning of biologically active kirsten murine sarcoma virus dna. | the unintegrated closed circular form of viral dna prepared from nih3t3 cells infected with kirsten murine sarcoma virus was cloned into bacterial plasmid pbr322. the closed circular dna, which consisted of two different-sized populations, was enriched from the virus-infected cells, linearized with bamhi, and inserted into pbr322 dna. four different recombinant dnas (clones 2, 4, 6, and 7) were obtained, and a physical map of each was constructed by using various restriction enzymes. clone 4 dna ... | 1981 | 6264139 |
| comparative effects of azathioprine, cyclophosphamide and frentizole on cellular immunity in mice. | this report extends previous observations on the immunosuppressive properties of cyclophosphamide (cpa), azathioprine and frentizole (15) to include murine models of cellular immunity. systemic and local graft vs host reactions (gvhr) were most effectively suppressed by cpa. in contrast to frentizole, both cpa and azathioprine were found to inhibit the proliferation of parental t-cells in a systemic gvhr. however, cpa was the only agent capable of inhibiting the proliferation of t-cells followin ... | 1981 | 6978364 |
| growth properties and susceptibility to viral transformation of skin fibroblasts from individuals at high genetic risk for colorectal cancer. | growth characteristics and susceptibility to viral transformation were compared in cultured skin fibroblasts from patients with gardner's syndrome (gs), those with familial polyposis coli (fp), asymptomatic family members, and unrelated controls. compared to cells from unrelated controls, cells from 4 of 5 gs patients were transformed by kirsten murine sarcoma virus at 100- to 1,000-fold increased efficiency. the transformation efficiencies of fibroblasts from 2 of 3 fp patients were 10- to 100- ... | 1981 | 6935464 |
| markedly elevated levels of an endogenous sarc protein in a hemopoietic precursor cell line. | the src gene product of harvey murine sarcoma virus is a 21,000-dalton guanine nucleotide-binding protein. we have recently shown that a wide variety of vertebrate cell strains and cell lines express much lower levels of an endogenous p21 immunologically related to the harvey murine sarcoma virus-coded p21. in this report, we have examined the levels of endogenous p21 in a unique hemopoietic precursor cell line, 416b, which was originally described as a continuous cell line of a hemopoietic stem ... | 1981 | 6821513 |
| 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 | |
| the biology, pathology and immunology of a virus induced rat osteosarcoma. i. biological behaviour and histopathology. | the biological behaviour and histopathology of an experimental osteosarcoma in rats are described as a model to study the human disease. the tumour was developed by injection of moloney murine sarcoma virus into the tibial marrow space of three strains of inbred new-born rats. the resulting neoplasm was highly malignant and arose after a short latent period of only 10 days. it was readily maintained in tissue culture and was transplantable to adult rats. the virus induced tumour resembled human ... | 1980 | 6937449 |
| antitumor effects of doxorubicin against a virally-induced rat osteosarcoma with minimal immunosuppression. | intratibial inoculation of a moloney strain of murine sarcoma virus (msv-m) in neonatal wistar-lewis rats produced osteosarcoma in 96% of animals and resulted in a median survival of 20 days. intraperitoneal (i.p.) administration of doxorubicin (adriamycin) (1-2 mg/kg/d, on day 10-12) resulted in reduced tumor growth and prolonged median survival to 95+ and 64 days, respectively. higher dose doxorubicin (3-4 mg/kg/d, on day 10-12) caused early lethal toxicity. autopsy data revealed a characteris ... | 1980 | 6937562 |
| experimental osteosarcoma in the mouse, induced by moloney's murine sarcoma virus. | the writers report an experimental trial on the mouse, consisting in the induction of osteosarcoma by inoculation of moloney's murine sarcoma virus (msv-m) into the proximal metaphysis of the tibia. this experiment was conducted on 90 balb/c female mice aged twenty-one days and of mean weight 12.8 g. one group of animals was also given immunodepressive drugs. the tumour developed in 100 per cent of cases, producing metastases in some of the animals and resulting in death in three cases. the radi ... | 1980 | 6938501 |
| effect of lactate dehydrogenase virus on chemically induced mouse lung tumorigenesis. | lactate dehydrogenase virus is the third in a series of viruses which have been examined for the capacity to alter chemically induced mouse lung tumorigenesis. this virus was given to strain a mice by i.p. injection either 4 weeks before, on the same days as, 4 weeks after, or 8 weeks after the s.c. injection of urethan (either 0.25 or 1.0 mg/g). the pulmonary adenoma response to urethan was suppressed in all of the lactate dehydrogenase-infected mice, with a maximum suppression of 30 to 40% whe ... | 1980 | 7349905 |
| intracellular rna complementary to the rna genome of the moloney--murine sarcoma virus complex. | 1980 | 7352370 | |
| in vitro translation of virion rna from moloney murine sarcoma virus. | 1980 | 7355580 | |
| effect of canavanine on murine retrovirus polypeptide formation. | canavanine is an arginine analog which is widely used to inhibit proteolytic processing of viral polyproteins. certain results obtained with canavanine have suggested that it may have other effects. therefore, we examined the effects of canavanine on the cell-free synthesis of murine retrovirus proteins. it was found that the electrophoretic mobility of the major gag-related cell-free product of both rauscher murine leukemia virus (r-mulv) and moloney murine sarcoma virus 124 (mo-musv-124) rna w ... | 1980 | 7365878 |
| suppression of murine retrovirus polypeptide termination: effect of amber suppressor trna on the cell-free translation of rauscher murine leukemia virus, moloney murine leukemia virus, and moloney murine sarcoma virus 124 rna. | the effect of suppressor trna's on the cell-free translation of several leukemia and sarcoma virus rnas was examined. yeast amber suppressor trna (amber trna) enhanced the synthesis of the rauscher murine leukemia virus and clone 1 moloney murine leukemia virus pr200(gag-pol) polypeptides by 10- to 45-fold, but at the same time depressed the synthesis of rauscher murine leukemia virus pr65(gag) and moloney murine leukemia virus pr63(gag). under suppressor-minus conditions, moloney murine leukemi ... | 1980 | 7373716 |
| effects of sodium butyrate on the membrane glycoconjugates of murine sarcoma virus-transformed rat cells. | the temporal relationship between butyrate-induced cellular flattening of murine sarcoma virus-transformed rat cells (msv-nrk) and alterations in certain surface-associated biochemical markers of transformation, e.g., surface glycopeptides, glycolipids, fibronectin, hexose uptake, and cell-substrate adhesion was examined. the induction of elevated levels of the ganglioside gm3 and of a gdla-like ganglioside were observed to precede or to parallel cellular flattening. likewise, enhanced incorpora ... | 1980 | 7380882 |
| genome organization of retroviruses. viii. nonproducer cell lines of mouse fibroblasts transformed by moloney murine sarcoma virus dna synthesized in vitro. | 1980 | 7395109 | |
| cytochalasin b-induced multinucleation of human tumor and normal cell cultures. | twelve human cell cultures derived from tumors, normal tissues, and derivative cultures transformed by either a rna tumor virus or chemical carcinogen were examined for their response to cytochalasin b (cb) and the expression of this marker was correlated with growth in soft agar and saturation density in monolayer culture. cell lines derived from carcinoma of the bladder (t24 and rt4), kidney (caki-1), prostate (du 145), and breast (mcf-7) multinucleated when growth in cb-supplemented medium, w ... | 1980 | 7397790 |
| isolation and characterization of naturally occuring deletion mutants of moloney murine sarcoma virus. | 1980 | 7423856 | |
| partial characterization of a moloney murine sarcoma virus 85,000-dalton polypeptide whose expression correlates with the transformed phenotype in cells infected with a temperature-sensitive mutant virus. | 1980 | 7423857 | |
| murine sarcoma growth factors affect the growth and morphology of cultured mouse epithelial cells. | a mouse embryo epithelial cell line, mmc-e, was used to study the effects of purified murine sarcoma growth factors (sgfs) on the growth of epithelial cells. murine sgf was a partially purified preparation from the serum-free culture media of mouse fibroblasts transformed by moloney murine sarcoma virus. sgfs stimulated dna-synthesis in resting cells and induced them to grow to higher densities than control cells. with continued exposure to sgfs, mmc-e cells lost their postconfluency inhibition ... | 1980 | 7440645 |
| polyclonal antibody synthesis and autoantibody formation in mice inoculated with murine sarcoma virus. | 1980 | 6989530 | |
| defective cytotoxic t-cell generation in moloney murine sarcoma virus-infected a/sn mice. | cytotoxic t-cells (ctl) could not be detected in spleen cell suspensions from moloney murine sarcoma virus (m-musv)-induced tumor-bearing a/sn and (a/sn x c57bl/6) f1 mice, with the a/sn-derived natural killer (nk)-sensitive yac-1 lymphoma cells used as targets. however, spleen t-cells from tumor-bearing (a/sn x c57bl/6)f1 mice were efficient killers against c57bl/6-derived rbl-5 cells. when tested for viral antigens by sera from mice with regressing atumors, yac-1 and rbl-5 cells cross-reacted. ... | 1980 | 6968372 |
| increased sensitivity of fibroblasts of skin from patients with adenomatosis coli and peutz-jegher's syndrome to transformation by murine sarcoma virus. | skin fibroblasts from family members of cases of adenomatosis coli (ac) and peutz-jegher's syndrome (pj) were examined for susceptibility to morphological transformation by moloney murine sarcoma virus (msv) of rate 78ai cells, which was found in the present study to contain both dualtropic and ecotropic murine leukemia virus (mlv). the fibroblasts from individuals with manifest ac (22 subjects) and manifest pj (5 subjects) were up to 5 times more susceptible to transformation by rat 78ai-msv(ml ... | 1980 | 6268477 |
| guanine nucleotide binding activity of the src gene product of rat-derived murine sarcoma viruses. | 1980 | 6261655 | |
| [a virus produced by human embryonic cells infected with moloney murine sarcoma virus]. | human embryonic cell cultures, infected with the mouse sarcoma virus, complex (moloney isolate), produced a virus that specifically transformed mink lung cells. the non-transforming helper virus could infect mouse cells as well as a wide range of other mammalian cells. these observations could suggest the presence of either several viruses in the virus stock and/or stable recombinants. | 1980 | 6774828 |
| structure of and alterations to defective murine sarcoma virus particles lacking envelope proteins and core polyprotein cleavage. | htg2 hamster cells produce a defective murine sarcoma virus lacking gp70 and, consequently, viral surface projections (knobs), but the lack of knobs appears to have no effect on intramembrane particle distribution. in addition, it has been noted that the core of the virus remains in the "immature" form as a result of the failure of the polyprotein precursor (p65) to undergo cleavage. however, incubation of htg2 virus with avian myoblastosis virus was found to yield specific cleavage products of ... | 1980 | 6257930 |
| 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 |
| heteroduplex analysis of cloned rat endogenous replication-defective (30 s) retrovirus and harvey murine sarcoma virus. | 1980 | 6255681 | |
| moloney murine sarcoma proviral dna is a transcriptional unit. | a portion of moloney murine sarcoma virus dna which is repeated at both ends of the provirus has been sequences. the nucleotide sequence, together with hybridization data obtained with in vitro pulse-labelled nascent viral rna, indicate that initiation and termination of rna synthesis occur within that region of the proviral dna. a model for transcriptional readthrough of termination signals during rna synthesis in this system is suggested. | 1980 | 6256637 |
| 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 |
| 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 |
| 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 |