bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tumor antigen extracts stimulate cytotoxicity against unrelated target cells
Authors: Lopez Diana M. , Sigel M. Michael 
Published: February 2007

AbstractA new cytotoxicity assay for the study of tumor antigens is described. Splenocytes from normal and mammary‐tumor‐bearing BALB/c mice were depleted of glass‐adherent cells, exposed to various concentrations of tumor extracts and mixed with 51Cr‐labelled chick red blood cells. Cytolysis evidenced by 51Cr release was determined 20 h after incubation at 37°C. Lymphocytes from tumor bearers exerted no cytotoxic action per se, but became cytolytic after confrontation with immunogenic tumor extracts. Although this cytotoxicity is expressed against targets other than the cells containing the sensitizing antigen, i.e., a non‐specific activity, its induction is strictly specific as evidenced by the following: (1) extracts of D1‐DMBA‐3 tumors exerted an inductive effect only in lymphocytes from mice bearing this tumor and not in lymphocytes from normal mice; and (2) extracts of normal tissues or of a non‐immunogenic mammary tumor, D1‐DMBA‐2, did not induce cytotoxicity in lymphocytes from normal or tumor‐bearing mice. This approach may provide a useful method for in vitro determination of cell‐mediated immunity in which specific reactions can be induced by tumor extracts as opposed to intact tumor cells.
Kinetics of the response of spleen cells from tumor‐bearing animals in an in vivo tumor neutralization assay
Authors: Gabizon A. , Small M. , Trainin N. 
Published: February 2007

AbstractThe behavior of spleen cells from tumor‐bearing mice, vis‐à‐vis isologous tumor cells, was investigated by means of an in vivo adoptive neutralization test. C3H/eB mice were challenged with tumor cells from a chemically induced fibrosarcoma. Spleens from these animals were removed at weekly intervals following tumor inoculation, mixed with tumor cells, and tested for their influence on tumor growth in syngeneic recipient mice. Two phases in the reactivity of spleen cells from tumor‐bearing mice were clearly distinguishable. In a first stage of tumor growth, these mice yielded specific tumor‐inhibitory cells conferring protection. Subsequently, the protective activity declined leading to a second phase characterized by tumor enhancement. Both protective and enhancing activities were shown to be mainly dependent on the presence of T cells.
In vitro sensitization to embryonic antigens
Authors: Friend Kathleen , Hellström Ingegerd , Hellström Karl Erik 
Published: February 2007

AbstractLymphoid cells from virgin, untreated BALB/c mice cultured 5 days on 12‐ or 13‐day syngeneic mouse embryo fibroblasts (MEF) or on cells from a syngeneic 3‐methylcholanthrene‐induced mouse sarcoma (1315) were cytotoxic for 1315 tumor target cells when tested with a microcytotoxicity assay. They did not kill embryo or skin fibroblast target cells. Lymphoid cells cultured with 11‐, 14‐ or 17‐day MEF were not cytotoxic for cells from the 1315 tumor, from embryo or from adult skin. Lymphoid cells from multiparous BALB/c mice cultured on 11‐, 12‐ or 13‐day MEF, on line 1315 sarcoma cells or on skin fibroblasts were cytotoxic for tumor target cells. MEF were killed by multipara lymphoid cells that had been cultured on 11‐, 12‐ or 13‐day MEF or on the 1315 tumor line. Multipara lymphoid cells cultured on 1315 cells or 12‐day MEF were cytotoxic for adult skin fibroblasts, while multipara lymphoid cells cultured on 14‐ or 15‐day MEF were not cytotoxic for any of the target cells. The data thus indicate that lymphoid cells can mediate both primary and secondary immune reaction in vitro to antigens shared by neoplastic and normal embryonic cells, and that the primary reactions appear to be more specific to putatively embryonic tumor antigen(s) than the secondary ones.
Immunoglobulin complexes in sera of patients with malignancy
Authors: Samayoa Edwardo A. , McDuffie Frederic C. , Nelson Audrey M. , Go Vay L. W. , Luthra Harvinder S. , Brumfield Hilton W. 
Published: February 2007

AbstractSera frour 146 patients with malignancy, 59 normal controls and 42 patients hospitalized with non‐malignant diseases were examined by a precipitin test with monoclonal rheumatoid factor (mRF) for the presence of circulating immune complexes containing IgG. Forty‐two (29%) of the sera from cancer patients but only two of the sera from patients in each of the control groups contained such material. Similar results were obtained with a radioimmuno‐assay for immune complexes based on the same mRF. Sera from 23 of 65 patients with metastatic malignancy (35%) had elevated levels of immune complexes by this latter test. The presence of the material was not related to the source of malignancy, presence of carcinoembryonic or hepatitis antigens or of such autoantibodies as rheumatoid factor or anti‐DNA. By density gradient ultracentrifugation the reacting material was identified as being of molecular size 19s or greater. It has not yet been further characterized with regard to the nature of any antigens present.
A case control study on immunity to two epstein‐barr virus‐associated antigens, and to herpes simplex virus and adenovirus in a population‐based group of patients with hodgkin's disease in denmark, 1971–73
Authors: Hesse J. , Ebbesen P. , Levine P. H. , Connelly R. R. , Mordhorst C. H. 
Published: February 2007

AbstractOne hundred and eighty‐five patients with untreated Hodgkin's disease (HD) comprising 86% of all new cases diagnosed in Denmark over a 2‐year period, were individually matched with healthy controls of the same age, sex and social class. In comparison to controls, HD patients showed significantly elevated mean antibody titres to Epstein‐Barr viral capsid antigen (EB‐VCA) and to herpes simplex virus, whereas no significant differences in mean titres were found for adenovirus common antigen. Subdivision of the patients by age, sex, social class, HL‐A antigens, stage of disease and histology did not alter this pattern, except that significant case‐control differences in EB‐VCA titres could be demonstrated only for the nodular sclerosis and lymphocyte predominance subgroups. After 1 year of treatment, a significant rise in EB‐VCA mean titre had taken place. Splenectomy seemed to promote this titre elevation. Neither the initial titres to EB‐VCA and EBV‐EA nor changes in titres over time were related to prognosis. The results of our study, which are more representative of a population of HD patients and controls than previously reported studies, confirm that the reported relationship between EBV and HD exists, but that the elevated EBV titres are probably not of etiologic significance in most HD patients.
Somatic cell hybrids between human lymphoma lines. III. Surface markers
Authors: Klein George , Rosén Anders , Terasaki Paul , Billing Ron , Honig Ron , Jondal Mikael , Zeuthen Jesper , Clements Geoffrey 
Published: February 2007

AbstractHybrids between two human lymphoma lines, Raji and Daudi (8A) and Raji and BJAB (83) were examined for genetically determined and/or differentiation‐related surface markers. HL‐A, B cell alloantigens, Fc and complement receptors, EBV receptors and β2 microglobulin showed an autonomous (“codominant”) expression in the hybrid. This is in contrast to most previous studies on other differentiation markers, involving as a rule crosses between cells of different lineages, where the differentiated pattern usually became “eclipsed” in the hybrid. Staining of activated complement and complement consumption tests showed intermediate or partially suppressed expression in the hybrids. This may be viewed in relation to the fact that these reactions do not merely depend on complement binding to the receptor, but also on subsequent activation and binding of the activated complement. A more complex interaction is also suggested for immunoglobulin production. Surface immunoglobulin showed a suppressive or intermediate pattern in both hybrids, whereas intracellular kappa chain production showed an amplification in the 83 hybrid. The β2 microglobulin deficiency of the Daudi parent was corrected in the Raji/Daudi hybrid. Two new HL‐A specificities, A10 and BW17, appeared on this hybrid which were not present on the parental lines. This suggests that the HL‐A deficiency of the Daudi cell is due to its lack of β2 microglobulin.
A dose‐response study on urethane carcinogenesis in rats and mice
Authors: Schmähl D. , Port R. , Wahrendorf J. 
Published: February 2007

AbstractSprague‐Dawley rats and NMRI mice were treated with urethane in the drinking water for 2 years. In both species the daily doses were: 100, 500, 2,500, and 12,500 μg/kg. The frequency of animals with malignancies increased steadily with increasing doses, beginning from 500 μg/kg/day for rats, and from 100 μg/kg/day for mice. To evaluate the possible cancer risk for man due to urethane in beverages, the observed response rates were used to extrapolate responses at lower doses. At a daily dose of 0.14 μg/kg/day (corresponding to daily consumption of a beverage with 10 ppb urethane by a 70‐kg man) the upper risk limits were estimated to be 3.2 in 100,000 for rats, and 470 in 100,000 for mice (modified Mantel‐Bryan procedure). Problems in calculating a possible cancer risk for man on the basis of animal observations are discussed. Since treatment of beverages with diethyldicarbonate leads to the formation of urethane, and since a cancer risk to man from urethane cannot be excluded, replacement of diethyldicarbonate by a toxicologically unobjectionable compound is called for.
Horizontal transmission of feline leukemia virus under natural conditions in a feline leukemia cluster household
Authors: Essex M. , Cotter S. M. , Sliski A. H. , Hardy W. D. , Stephenson J. R. , Aaronson S. A. , Jarrett O. 
Published: February 2007

AbstractTen post‐weanling 4‐month‐old cats, designated “tracers”, were placed in a feline leukemia cluster household to determine the efficiency of horizontal transmission of feline leukemia virus (FeLV). The tracer cats were confirmed as negative for prior exposure to FeLV. Following placement in the leukemia cluster environment, the tracer cats were serologically monitored at intervals of 3–6 weeks for a total period of 1 year. The tests employed included the detection of FeLV using fixed‐cell immunofluorescence and the detection and titration of antibody to: (1) the feline oncorna‐virus‐associated cell membrane antigen (FOCMA), as detected by membrane immunofluorescence; (2) viable FeLV, using serum neutralization; (3) virion core protein p30, using radioimmunoprecipitation; and (4) virion glycoprotein gp70, using radioimmunoprecipitation. All of the tracers had evidence of horizontal infection by FeLV, by several criteria. Seven of the 10 had virus that could be isolated from plasma. All of these 7 developed a terminal illness within 18 months; 3 developed aplastic anemia, 3 infectious peritonitis, and 1 lymphoma. The remaining 3 were negative for FeLV by both virus isolation and fixed‐cell immunofluorescence. These 3 did, however, develop high antibody titers by all four criteria and they remained healthy throughout the examination period. These results clearly indicate that unprotected post‐weanling cats brought into a leukemia exposure household environment have a high risk of becoming infected with FeLV. Furthermore, a large proportion of the cats are at risk for development of persistent viremia and FeLV‐related diseases.
Genetic association of the humoral and cellular immune responses of rats to moloney sarcomas
Authors: Veit Bruce C. , Jones Joe M. , Miller Glenn A. , Feldman Joseph D. 
Published: February 2007

AbstractBrown Norway (BN), Lewis (Le), F1 hybrids of Le × BN (LBN) and parent‐to‐LBN backcross rats were tested for cellular and humoral responses to a BN Moloney sarcoma. Regardless of AgB phenotype, BN backcrosses produced low levels of cell‐mediated cytotoxicity (CMC) that were comparable to those of BN parents. Le backcrosses developed high levels of CMC similar to those produced in Le parents. An inverse relationship between levels of CMC and serum antibodies (cytotoxic for tumor cells and anti‐p30 of MuLV) was observed; BN parents and backcrosses produced high levels of serum antibodies whereas levels in Le parents and backcrosses were low. LBN hybrids developed relatively high levels of CMC and serum antibodies. An additional finding was that the CMC response in Le parents and back‐crosses was directed primarily against tumor‐associated antigens rather than histocompatibility antigens expressed on the tumor cells. The results suggest that humoral and cellular responses to Moloney sarcoma in rats are not determined solely by the major AgB histocompatibility locus but do have a genetic association. This genetic association was detected with a 51Cr release assay which detects T‐cells, suggesting that select populations of effector T‐cells may be genetically regulated.
Human pancreatic carcinoma (mia paca‐2) in continuous culture: Sensitivity to asparaginase
Authors: Yunis Adel A. , Arimura Grace K. , Russin David J. 
Published: February 2007

AbstractAn undifferentiated human pancreatic carcinoma has been established in continuous culture and is grown in Dulbecco's modified Eagle's medium fortified with 10% fetal calf serum and 2.5% horse serum. The established cell line (MIA PaCa‐2) has a doulbing time of 40 h. The cells are large with abundant cytoplasm, exhibit a high degree of aneuploidy and have a tendency to grow on top of other cells. MIA PaCa‐2 grows in soft agar with a colony‐forming efficiency of 19%. Both MIA PaCa‐2 cells and a cell line from another pancreatic carcinoma obtained from National Cancer Institute (NCI) are sensitive to asparaginase, a property not shared by several other human tumor cell lines tested.
Molecular interactions between adriamycin and x‐ray damage in mammalian tumor cells
Authors: Byfield John E. , Lee Young C. , Tu Lorna 
Published: February 2007

AbstractThe effect of the anthracycline antibiotic, Adriamycin (Ad), on the sedimentation properties of pre‐labelled mammalian DNA has been studied. Ad induces DNA degradation in vivo in both excision repair‐competent (HeLa and Me‐180) cells and in excision repair‐deficient (REQ) cells. When X‐irradiated cells are exposed to Ad during the period of repair of DNA single‐strand breaks, small numbers of residual breaks persist following completion of repair. These are attributable to those induced by Ad alone. The effects of Ad and X‐rays therefore appear to be similar and additive. No clear‐cut evidence that Ad can inhibit the repair of X‐ray‐induced DNA single‐strand breakage was found. Ad also induces the formation of DNA double‐strand breaks and inhibits the repair of X‐ray‐induced base damage (repair replication). The induction of DNA strand breakage may be responsible for Ad cell toxicity and may contribute to its capacity to enhance primary X‐irradiation damage when the two types of lesions co‐exist.
Murine sarcoma virus (msv)‐induced tumors in mice. I. Distribution of msv‐immune cytolytic t lymphocytes in vivo
Authors: Plata F. , Sordat B. 
Published: February 2007

AbstractQuantitative studies using a 51Cr release assay were performed to analyse the time‐course of appearance and specificity of cytolytic cells in C57BI/6 mice inoculated with Moloney murine sarcoma virus (MSV). Various lymphoid organs were studied including spleen, mesenteric lymph nodes (MLN), lymph nodes regional to the MSV‐induced tumor (RLN), and peripheral blood. Furthermore, the kinetics of appearance of cytolytic cells within the MSV‐induced tumor was determined. In agreement with previous studies, it was found that cytolytic T lymphocytes (CTL) specific for MSV‐associated antigens were present among the cells extracted from the tumor and from the lymphoid organs. However, differences in the kinetics of CTL activity could be documented: lymphoid cells from spleen, RLN and peripheral blood showed peak activity at the time of maximum tumor diameter, while intratumoral cells showed peak activity at the onset of tumor regression. MLN cells showed cytolytic activity only when tumor regression had begun. Naturally cytotoxic cell populations of thymus‐independent origin, present in normal control mice, were also detected in MSV‐infected mice.
Polyoma genome transcription in transformed mouse cells growing in culture and as tumors in syngeneic mice
Authors: Grady Leo J. , North Arlene B. , Campbell Wayne P. 
Published: February 2007

AbstractThe strands of the polyoma genome coding for early and late viral RNA were separated by means of asymmetric cRNA synthesized under high salt conditions by Escherichia coli RNA polymerase. Each strand was then employed in RNA‐DNA hybridization experiments to determine the degree to which it is transcribed in transformed cells under several conditions. Except for a concanavalin‐A‐selected revertant, approximately one‐quarter of the early strand was expressed in all of the situations investigated. In contrast, while no significant late strand transcription was detected in transformed cells in culture, the tumors induced by these cells contained transcripts complementary to about 12% of this strand. The results are discussed in terms of current knowledge of the amount of the virus genome required to transform cells.
Comparative studies on ebv antigens by immuno‐fluorescence and immunoperoxidase techniques
Authors: Stephens R. , Traul K. , Gaudreau P. , Yeh J. , Fisher L. , Mayyasi S. A. 
Published: February 2007

AbstractThree groups of EBV antigens, VCA, MA and EA, were compared by the techniques of electron microscopic immunoperoxidase (IP) and immuno‐fluorescence (IF). P3HR‐1 and EBV superinfected Raji cells served as targets for labelled sera from patients with BL, NPC and IM or from healthy donors. 125I peroxidase‐labelled antibodies were also prepared to determine, autoradiographically, the penetration of the complex into the cell system, and to monitor the incubation and washing procedures. The development of a gentle sedimentation technique proved critical in handling the fragile target cells. VCA and MA were readily identified and localized by both procedures without significant modification of the basic techniques. Indentification of early antigens by IP required modification of the fixation method to include a brief treatment in acetone. The diffuse early antigen (EAD) was found to be associated with cellular ribosomes.
Tumorigenicity of human hematopoietic cell lines in athymic nude mice
Authors: Nilsson Kenneth , Giovanella Beppino C. , Stehlin John S. , Klein George 
Published: February 2007

AbstractHuman hematopoietic cell lines, which had been classified on the basis of studies on clonality, and morphological, chromosomal and functional parameters as lymphoblastoid cell lines (LCL) of presumed non‐neoplastic origin, and lymphoma, myeloma and leukemia lines of proven malignant origin, were tested for tumorigenic potential on subcutaneous transplantation to nude mice and for capacity to grow in semi‐solid medium in vitro Recently established LCL failed to grow both in nude mice and in agarose. In contrast, some of the LCL which had developed secondary chromosomal alterations during continuous cultivation for periods exceeding several years were tumorigenic and/or had the capacity to form colonies in agarose. Most lymphoma lines formed colonies in agarose and tumors in the mice. One of the two myeloma lines formed subcutaneous tumor which, however, showed no progressive growth. The other myeloma line failed to grow. Both myeloma lines, however, formed colonies in agarose. The myeloid leukemia line was tumorigenic while two of the three tested lymphocytic leukemia lines failed to grow in the mice. All leukemia lines formed colonies in agarose. We conclude from this study that: (1) Of the two types of Epstein‐Barr virus containing cell lines [LCL and Burkitt lymphoma (BL) lines], only BL lines were shown to form tumors when inoculated subcutaneously in nude mice and had the capacity to grow in agarose in vitro. This shows that EBV transformation per se does not necessarily render lymphocytes tumorigenic in nude mice. The capacity to form colonies in agarose is not acquired either. (2) Changes of the karyotype and several phenotypic characteristics which occur in the originally diploid LCL during prolonged cultivation in vitro may be accompanied by the acquisition of the potential to grow subcutaneously in nude mice and in agarose in vitro. (3) The inconsistency with regard to the capacity of some of the neoplastic cell lines to grow in nude mice or in agarose seems to underline that neither of the two tests is a reliable criterion for malignancy of human lymphoma, leukemia and myeloma cell lines.
Surface membrane changes in lymphocytes from patients with infectious mononucleosis
Authors: Mintz Uri , Sachs Leo 
Published: February 2007

AbstractPeripheral blood lymphocytes from 20 patients with acute infectious mononucleosis (IM) were studied for cell aggregation and for cap formation by concanavalin A (Con A). The lymphocytes from these patients showed 5.2±1.5% cells with a Con‐A‐induced cap and a high degree of cell aggregation without Con A, compared to 27.7±3.2% caps and a low degree of cell aggregation with normal lymphocytes. The lymphocytes from IM patients were fractionated to enrich for T and B cells. There was a low frequency of cap formation in both T and B cells, but the high degree of cell aggregation without Con A only occurred with B cells. Studies with four patients in clinical remission from acute IM have shown that the frequency of Con‐A‐induced cap formation only returned to normal more than 3 months after the beginning of clinical remission and that even at 6 months the cells still showed a high degree of cell aggregation. The results indicate that a high degree of B‐cell aggregation and a low percentage of B and T cells with a Con‐A‐induced cap were associated with acute IM and that the changes associated with a high degree of B‐cell aggregation were by themselves not sufficient to cause the disease.
Detection of cellular immunity to tumor‐associated antigen(s) in mice by the macrophage spreading inhibition test
Authors: Svoboda Ivna , Mažuran Renata , Rabatić Sabina , Silobrčić V. 
Published: February 2007

AbstractSoluble preparations of antigens from a methyl‐cholanthrene‐induced fibrosarcoma of C57BI mice were prepared by homogenization of tumor tissue and high‐speed centrifugation of the homogenate. These preparations were able to sensitize syngeneic mice to tumor‐associated antigens (TAA) of the fibrosarcoma, and to provoke a delayed hypersensitivity reaction when injected into the footpad of sensitized mice. Furthermore, the same soluble preparations could inhibit in vitro the spreading of peritoneal macrophages from mice sensitized to TAA. A similar inhibition of macrophage spreading was obtained when peritoneal cells from C57BI mice, bearing transplants of the fibrosarcoma, were incubated with the preparations. We conclude that the macrophage spreading inhibition test, like other in vitro assays, can detect cell‐mediated immunity to tumor‐associated antigens.
Transformation of rabbit kidney cells by bkv(mm) human papovavirus
Authors: Mason David H. , Takemoto Kenneth K. 
Published: February 2007

AbstractPrimary rabbit kidney cells were transformed by BKV(MM), a papovavirus isolated from the urine of a child with the Wiskott‐Aldrich syndrome. The transformed cells contained BK T‐antigen, but no antigen that reacted with SV40 U‐antiserum. The transformed cells failed to produce tumors in nude mice, and BKV (MM) was not rescued from transformed cells by cell fusion or chemical induction methods. The transformed cells supported the growth of rabbit kidney vacuolating virus (RKV), and could be used to quantitate RKV by plaque formation under an agar overlay.