bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depression of complement activity in three strains of mice after tumor transfer
Authors: Drake Walter P. , Legendre Stephen M. , Mardiney Michael R. 
Published: February 2007

AbstractBoth immune adherence and hemolytic complement activity were measured as a function of time after either intraperitoneal or subcutaneous injection of six transplantable tumors carried in three strains of mice. There was a lack of correlation between complement activity measured by these assays in accord with other studies on human cancer patients. The data indicate that host complement activity was depressed in all cases following tumor transfer and suggest that the serotherapy of murine tumors using passively administered anti‐tumor serum may be compromised by host complement insufficient to mediate tumor cytolysis in vivo.
A rapid destructive effect of the Schmidt‐Ruppin strain of rous sarcoma virus on transformed rat cell lines
Authors: Reinisch Carol L. , Bang Frederik B. 
Published: February 2007

AbstractA cytopathic effect was induced by the Schmidt‐Ruppin strain of Rous sarcoma virus (RSV‐SR) in five of nine rat tumor cell lines tested in vitro. The cells showed irreversible cytopathic change as early as 24‐48 h after infection. Of the leukemogenic and tumorigenic viral agents tested, only RSV‐SR induced the rapid Rous cytopathic effect. Virus was recovered 8 days after inoculation of the tumor cell lines XC and M41. The effect was neutralized by specific anti‐RSV‐SR antiserum. Correlation between oncogenicity of the rat tumor lines in the syngeneic host and their susceptibility to RSV‐SR was incomplete.
Inheritance of susceptibility to friend mouse leukemia virus. XI. Genetic control of late splenomegaly
Authors: Odaka Takeshi 
Published: February 2007

AbstractGenetic control of splenomegaly which occurs at a late stage of Friend leukemia virus infection was studied in hybrid mice between DDD‐Fvr and C57BL/6. It was demonstrated that this late splenomegaly was mainly controlled by a single autosomal locus with the dominant allele for resistance. This locus may be idential with or genetically linked with the locus which controls the level of virus multiplication at an early stage of infection. Considered together with previous findings, splenomegaly induced by Friend leukemia virus in mice is classified into two types, early and late, both being controlled by two separate gene loci.
Isolation and characterization of a primate sarcoma virus: Mechanism of rescue
Authors: Scolnick Edward M. , Parks Wade P. 
Published: February 2007

AbstractA clonal isolate of an RNA‐containing sarcoma virus derived from a spontaneous woolly monkey fibrosarcoma has been obtained. The woolly sarcoma virus transformed cells do not spontaneously yield infectious virus but do contain the woolly gs antigen. The primate sarcoma virus can be rescued with comparable efficiency by superinfection with either murine or primate helper type‐C viruses. During rescue with murine helper type‐C virus, the intracellular level of woolly monkey gs antigen does not rise in proportion to the production of helper gs antigen, or in proportion to the production of transmissible focus‐forming virus. The results suggest that the mechanism of rescue may simply involve an assembly of sarcoma components into an infectious particle during the production of the helper type‐C virus.
Reversion in hybrids between SV40‐transformed hamster and mouse cells
Authors: Wiblin C. N. , Macpherson I. 
Published: February 2007

AbstractThe expression of the transformed phenotype was studied in segregants from a hybrid cell line resulting from the fusion of SV40‐transformed BHK21 Syrian hamster cells (thioguanine resistant) and 3T3 mouse cells (bromodeoxyuridine resistant). Since the hamster cell parent was sensitive to bromodeoxyuridine, segregants lacking chromosomes could be obtained by “back‐selection” in this drug. These segregants retained transformed characteristics, despite substantial loss of hamster chromosomes. Selected segregants were treated further with cytotoxic antibody raised against the hamster parent. The majority of the segregants isolated retained all transformed characteristics, even when the hamster chromosome complement was greatly reduced. Some derivatives showed properties intermediate between a transformed and an untransformed state. Two revertant clones were also isolated which lacked transformed characteristics and contained no metacentric (hamster) chromosomes. Unlike the other segregants, no SV40 virus could be recovered from these cells. The implications of these results with respect to the integrated status of transforming SV40 genomes are discussed.
Aggregation of feline lymphoma cells by hyaluronic acid
Authors: Wasteson Åke , Westermark Bengt , Lindahl Ulf , Pontén Jan 
Published: February 2007

AbstractAddition of media from cultured human sarcoma or glioma cells to cultures of suspended feline lymphoma cells (established line FL 74) induced visible aggregation of the lymphoma cells within a few minutes. A number of other normal and malignant cells, including a series of human lymphoid cells, failed to aggregate under identical conditions. The aggregation process showed no temperature dependence, within a range of 4° C to 37° C, and did not require divalent metal ions. The cell‐aggregating factor was heat‐stable and resistant to digestion with trypsin. It was identified as hyaluronic acid on the basis of its macromolecular and polyelectrolyte properties in conjunction with its susceptibility to various enzymes. A standard preparation of hyaluronic acid induced aggregation of suspended FL 74 cells at concentrations of 30 ng /ml or more. Chondroitin sulphate, chondroitin sulphate proteoglycan, dermatan sulphate, heparan sulphate and heparin did not aggregate the cells, nor did partially depolymerized hyaluronic acid. Pretreatment of the FL 74 target cells with trypsin abolished their clumping ability, implying the presence of a trypsin‐sensitive receptor at the cell surface. Trypsinized and washed cells regained their aggregation properties with hyaluronic acid within a 24 h period in continued culture. The interaction of hyaluronic acid with its receptor was studied by inhibition experiments, in which FL 74 cells were subjected to hyaluronic acid after preincubation with various oligosaccharides. Tetra‐ and hexasaccharides, derived from either hyaluronic acid or chondroitin sulphate, were able to prevent aggregation of the cells by polymeric hyaluronic acid.
Regression of polyoma tumor metastasis by combined unblocking and bcg treatment‐correlation with induced alterations in tumor immunity status
Authors: Bansal S. C. , Sjögren Hans O. 
Published: February 2007

AbstractImmunotherapy, in the form of inoculations of “unblocking” antitumor sera alone or combined with BCG and splenectomy, was tried in a metastasis model in animals. W/Fu rats were exposed to progressively growing polyoma tumor isografts which were subsequently excised, and then rechallenged with an isograft of the same tumor as a “metastasis”. The immunological manipulation was initiated at the time of rechallenge and, although it was not capable of preventing tumor outgrowth, it caused a complete regression of the outgrowing tumor nodules within a few weeks in 7/7 and 5/16 rats in two different experiments. An attempt was also made to inhibit well‐established spontaneous tumor metastasis to the lung by repeated inoculations of unblocking antitumor serum. Prolonged survival was obtained in four out of nine rats and one of these animals was free of tumor when killed after 4 months. The spread of the tumor to various organs was significantly restricted by the therapy, indicating partially inhibited tumor growth. An attempt was made to establish correlations between inhibition of tumor growth in vivo and certain alterations in the antitumor immunity as analyzed by in vitro techniques. Disappearance of serum blocking activity and appearance of rat complement‐dependent cytotoxicity in serum was seen in all rats with regressing tumors but not in the other animals, although they had received the same treatment. The lymphocyte cytotoxicity was increased to about the same extent in regressor and progressor rats.
Cell‐mediated immunity and blocking factors in patients with tumours of the central nervous system
Authors: Kumar S. , Taylor G. , Steward J. K. , Waghe M. A. , Morris‐Jones P. 
Published: February 2007

AbstractLymphocytotoxicity studies were carried out in both the autochthonous and allogeneic situations in nine astrocytomas, seven medulloblastomas and two ependy‐momas. Tumour type‐specific lymphocytotoxicity was demonstrated. The degree of lymphocyte‐mediated tumour‐cell killing did not decrease with the duration of apparent clinical cure. Higher degrees of tumour‐cell killing were found in the autochthonous as compared with the allogeneic combinations. Blocking factor was demonstrated in only three patients.
In vitro cytotoxicity and in vivo tumor enhancement induced by mouse spleen cells autosensitized in vitro
Authors: Ilfeld David , Carnaud Claude , Cohen Irun R. , Trainin Nathan 
Published: February 2007

AbstractThe immuno‐reactivity of C57BL mouse spleen cells previously sensitized in vitro against syngeneic fibroblasts or syngeneic 3LL Lewis tumor cells was investigated. The sensitized spleen cells were assayed in vitro to test their cytotoxicity against the 3LL tumor cells. In addition, spleen cells autosensitized against syngeneic fibroblasts were mixed with 3LL tumor cells and injected into syngeneic recipient mice in order to ascertain their influence on tumor growth. The in vitro assay indicated that lymphoid cells specifically sensitized against either fibroblasts or tumor cells were equally cytotoxic against the 3LL target cells. On the other hand, in the in vivo experiments lymphoid cells sensitized against syngeneic fibroblasts promoted the growth of the 3LL tumor. An attempt to explain the underlying mechanisms involved in the paradoxical behavior of autosensitized lymphocytes is reported herein.
Interferon and cell division. VIII. Effect of interferon on macromolecular synthesis in L1210 cells in vitro
Authors: Brouty‐Boyé D. , Macieira‐Coelho A. , Fiszman M. , Gresser I. 
Published: February 2007

AbstractInterferon inhibits multiplication of murine leukemia L1210 cells and the effect is evident 18 h after subcultivation. At this time a significant decrease in the synthesis of total RNA and protein was observed in interferon‐treated cultures compared to control cultures. Likewise, the formation of polyribosomes was inhibited in interferon‐treated cultures although no effect was observed on the formation of the ribosomal subunits. As control cells and interferon‐treated cells continued to multiply and the cultures attained cell density saturation, the differences in macromolecular synthesis and polyribosome formation between the cultures became less marked. Confidence that interferon itself was responsible for the effects observed stemmed from the use of highly purified interferon preparations and the availability, as a cell control, of a subline of L1210 cells resistant to interferon action. The possibility that a single mechanism of action is common to the antiviral effect of interferon and its effect on cell division is discussed.
High level of alpha‐fetoprotein in sera of adult mice
Authors: Pihko Helena , Ruoslahti Erkki 
Published: February 2007

AbstractMouse a‐fetoprotein (AFP) was purified by making use of its immunological cross‐reaction with rabbit AFP. A radioimmunoassay, developed for mouse AFP, was used to measure AFP concentrations in the sera of adult mice of different inbred strains. The level of adult mouse AFP was found to be 30–350 ng/ml, which is about 10 times higher than has been reported for humans and rats. An association seems to exist between the high basal level of AFP and the remarkably high incidence of spontaneous hepatomas in mice.
Nasopharyngeal carcinoma. IV. Evolution of complement‐fixing antibodies during the course of the disease
Authors: De‐Thé Guy , Sohier Roger , Ho John H. C. , Freund Robert 
Published: February 2007

AbstractSequential sera from 37 patients with nasopharyngeal carcinoma (NPC), with either controlled or uncontrolled tumours after radiotherapy, were studied for complement‐fixing (CF) antibodies against a soluble antigen extracted from the QIMR‐WIL lymphoblastoid line. When compared with results obtained previously with the same antigen on sequential Burkitt's lymphoma (BL) sera, the NPC sera exhibited (1) approximately ten‐fold higher CF antibody titres than the BL sera; (2) an overall stability of CF titres in the uncontrolled tumour groups contrasting with the situation in BL; (3) a two‐ to four‐fold decrease in CF titres in the controlled tumour groups; (4) similar CF titres in patients at stage I or IV of the disease. The above suggests an active and long‐standing EBV infection before and during the development of the clinical NPC disease.
The deficient density‐dependent growth control of human malignant glioma cells and virus‐transformed glia‐like cells in culture
Authors: Westermark Bengt 
Published: February 2007

AbstractThe density‐dependent growth control of eight established human glioma lines and virus‐transformed human glia‐like cells has been investigated. All neoplastic lines reached higher terminal cell densities than the corresponding normal glia‐like cells. A marked decrease in proliferation rate occurred at high cell densities which could not be explained by medium depletion or accumulation of toxic substances. An absolute resting phase was not reached by the neoplastic cells; a considerable residual DNA synthesis continued even at the highest cell density levels which could be reached. The intervals of the cell cycle were determined on one glioma line. Cells inhibited in crowded cultures were arrested in G1. The results imply that at least a proportion of neoplastic human glia lines retain a degree of topoinhibition, i.e. are still sensitive to growth restraint induced by increased cell density. However, topoinhibition was never as complete as among normal cells, since possibly cell density‐independent (“autonomous”) multiplication was maintained at a fairly high rate even at the abnormally high cell densities which all neoplastic lines attained.
A quantitative system for assay of malignant transformation by chemical carcinogens using a clone derived from BALB/3T3
Authors: Kakunaga Takeo 
Published: February 2007

AbstractA31–714, a subclone isolated from clone A31 of the BALB/3T3 line showed a high degree of contact inhibition and an extremely low incidence of spontaneous transformation. Treatment of this subclone with 4‐nitroquinoline‐1‐oxide, 3‐methylcholanthrene, benzo(a)pyrene or N‐methyl‐N'‐nitro‐N‐nitrosoguanidine produced foci of multilayered growth on the background of contact‐inhibited monolayer within 2 to 4 weeks. In this system the transformation frequency can be determined quantitatively on either an inoculated cell basis or a surviving cell basis. The transformation frequency increased with the concentration of carcinogens within a certain range, and was affected by the duration of treatment and the cell density at the time of treatment. Treatment with DMSO alone or with the non‐carcinogenic substances, 4‐nitroquinoline, 4‐aminoquinoline‐1‐oxide, phenanthrene and pyrene, did not cause any transformation. The cytotoxic effects of carcinogens were not directly correlated with the transformation frequencies. All transformed cell lines derived from each focus showed characteristics known as the indices of malignant transformation, such as a criss‐cross pattern or piling up of cells, a high saturation density and the ability to grow progressively in soft agar. When the transformed cells were injected into the skin of the back of newborn or adult mice at a dose of 106 cells, fibrosarcomas were produced at the site of injection after 3–6 weeks. Neither untreated A31–714 cells nor morphologically untransformed cells in cultures with foci produced tumors on injection at a dose of 107 cells. In general, transformed cells had a reduced cloning efficiency, and almost the same susceptibility to the cytotoxic effects of carcinogens as untransformed cells, though these properties varied in different lines.
Immunogenicity and immunosensitivity of SV40‐transformed cells with different oncogenic potentials
Authors: Stillström J. 
Published: February 2007

AbstractME1 C9, a cloned line of mouse embryo cells, transformed by SV40 in vitro, and its more malignant progeny, ME1 C9‐V15, derived from a tumor of the 15th consecutive passage of ME1 C9 in vivo, were compared as regards immunogenicity and immunosensitivity in syngeneic CBA mice. A threshold zone of immunization with ME1 C9 and ME1 C9‐V15 cells in the range of 103‐105 irradiated cells was indicated, after which the immunized animals were 1,000 times more resistant. There was no significant difference in immunizing potential between ME1 C9 and ME1 C9‐V15 cells at any dose level. A heterologous line of SV40‐transformed rat cells was significantly less immunogenic than the syngeneic cells. The growth of ME1 C9‐V15 cells could be enhanced after immunization with spontaneously transformed ME3 cells or with a small dose of ME1 C9 cells. The immunosensitivity of the ME1 C9 and ME1 C9‐V15 cells was measured as a sensitivity index in uniformly immunized animals. Both lines appeared immunosensitive if the animals were sufficiently immunized. The less malignant cells, ME1 C9, appeared more immunosensitive than the more malignant ME1 C9‐V15 cells in seven out of nine experiments, but only once was the difference between the lines significant. The interpretation of differences of sensitivity indices is discussed, and a possible role of blocking factors is considered.
Expression of fetal antigens and tumor‐specific antigens in SV40‐transformed cells. I. Serological analysis of the antigenic specificities
Authors: Ting Chou‐Chik , Ortaldo John R. , Herberman Ronald B. 
Published: February 2007

AbstractThe fetal antigens expressed in a variety of tumors have previously been shown to be different from tumor‐specific antigens. The present study on the expression of fetal antigens in various SV40‐transformed cells showed that more than one fetal antigen may be found in these cell lines, and that the expression of fetal antigens was not directly related to the function of the SV40 genome. These fetal antigens were not found in syngeneic spleen cells but were found in the normal spleens of some other strains of mice.
Intracerebral transplantation of human rhabdomyosarcoma cells into fetal and newborn kittens
Authors: Gardner Murray B. , Johnson Eden Y. , Rasheed Suraiya , McAllister Robert M. 
Published: February 2007

AbstractA human rhabdomyosarcoma cell line (RD) was transplanted intracerebrally in fetal kittens in an attempt to repeat the recovery of an RD‐114‐like virus. No virus was recovered from six such transplant tumors. Similar transplant tumors formed by RD cells productively infected prior to transplantation with feline leukemia virus or murine sarcoma virus released viruses that were not detectably altered from the parent viruses.
The stimulatory effects of bearing primary methylcholanthrene‐induced tumors upon the murine lymphoreticular system
Authors: Smith Richard T. , Konda Susumu 
Published: February 2007

AbstractThese studies explore mechanisms involved in the apparent immunodeficiency associated with the development of primary tumors. Methylcholanthrene fibrosarcomas were induced in five inbred strains of mice, and the cellular parameters of spleen‐cell immunologic function were measured either after the tumors reached a constant size or following a specific period of growth. T‐cell numbers, as indicated by the subpopulation susceptible to anti‐θ and complement cytotoxicity, and T‐cell functions including PHA mitogenicity, primary alloantigen recognition, and T cooperation were decreased proportionately, although they remained unchanged or were increased absolutely. Susceptibility to LPS mitogenicity, an apparent B‐cell function, was increased relatively and absolutely. The B‐cell function of anti‐SRBC production was also increased. Colonyforming units increased in number, but they were insufficient to account for significant proportions of the spleen cell population. It was concluded that the animal bearing a primary MCA tumor is deficient in neither T nor B cells and that the effect of the tumor upon immune function is stimulatory.
Plasma‐cell and tumor‐associated membrane antigens of mouse plasmacytoma MOPC‐315 and MOPC‐460
Authors: Comoglio P. M. , Forni G. 
Published: February 2007

AbstractRabbit and syngeneic mouse antisera produced against solubilized membrane antigens from plasma‐cell tumors MOPC‐315 and MOPC‐460 recognize neoplastic plasma‐cell antigens that are not detectable in normal tissues. The rabbit antisera showed precipitating antibodies against two tumor‐associated antigens expressed in both MOPC‐315 and MOPC‐460 cells and unrelated to plasma‐cell‐specific antigens or myeloma proteins. These were called embryo (EM) antigen and A‐particle‐associated (Aa) antigen. The EM‐antigen seemed to be related to mitotic activity and was also expressed by a mouse adenocarcinoma and by mouse embryo cells. The Aa‐antigen was detected by immuno‐precipitation in all of nine different mouse tumors. Its purification by reverse immunoadsorption demonstrated that it consisted of two related components. Syngeneic mouse antisera showed precipitating antibodies against only part of the Aa‐antigen determinants recognized by rabbit antisera. Lastly, one mouse antiserum precipitated with an antigen of unique specificity detectable on MOPC‐315 only.
Sensitivity to guinea‐pig serum of hamster cells transformed in vitro by two strains of the rous sarcoma virus
Authors: Bataillon G. 
Published: February 2007

AbstractWhereas cloning efficiency in soft agarose of untransformed hamster BHK 21/13 cells is strongly reduced when the cells are pre‐incubated with guinea‐pig (GP) serum, BHK 21/13 cells transformed by the Bryan strain of Rous sarcoma virus are unaffected by the same treatment; sensitivity of BHK 21/13 cells transformed by the Schmidt‐Ruppin strain of Rous sarcoma virus is intermediate. It is suggested that GP serum contains heterospecific cytotoxic substances directed against a xenogeneic surface antigen present on BHK 21/13 cells, and to a lesser extent, on BHK 21/13 cells transformed by SR‐RSV; this antigen is not detectable on the surface of BHK 21/13 cells transformed by the B‐RSV but can be “unmasked” after treatment with neuraminidase.
Potentiation of RSV rescue from rsv‐transformed “poorly” virogenic cell lines by 5‐bromodeoxyuridine treatment before fusion with chick embryo fibroblasts
Authors: Donner L. , Sainerová H. , Svoboda J. , Scherneck S. 
Published: February 2007

AbstractThe rescue of RSV from the “poorly” virogenic RSV‐transformed rat lines LW13‐RsK1 and LW13‐RsK4 was achieved only after treatment with 5‐bromodeoxyuridine (BUdR) before fusion with chicken embryo fibroblasts. Treatment of these lines with mitomycin C (MC) before fusion did not result in RSV rescue. Treatment of RSV‐transformed non‐virogenic mouse lines, RVA4 and RVP3, with BUdR or MC before fusion with chick embryo fibroblasts did not lead to the production of RSV.
Antigenic relatedness of simian C‐type viruses
Authors: Rangan S. R. S. 
Published: February 2007

AbstractThe two simian C‐type viruses, gibbon lymphoma (GLV) and simian sarcoma (SSV‐1), are compared for their antigenic relatedness by serum‐neutralization techniques appropriate for the respective virus. While GLV was neutralized completely by its homologous antiserum, its replication was merely delayed by anti‐SSV‐1 serum. Both anti‐SSV‐1 and anti‐GLV antisera neutralized SSV‐1 and its associated virus (SSAV‐1). It is concluded that the simian viruses are antigenically related but distinct from each other and unrelated to feline leukemia virus. The results also suggest that SSV‐1 and SSAV‐1 possess identical envelope antigens.