bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vitro „education”︁ on autologous human sarcoma generates non‐specific killer cells
Authors: Martin‐Chandon Marie‐Rose , Vanky Farkas , Carnaud Claude , Klein Eva 
Published: February 2007

AbstractThe cytotoxic effects mediated by lymphocytes from cancer patients after in vitro „education”︁ on autologous tumor cells have been investigated. Peripheral blood lymphocytes from three sarcoma patients were cultivated on autologous tumor‐cell monolayers and tested thereafter in a micro‐cytotoxicity assay against tumor and fibroblast cells. This procedure led to the progeny of non‐specific killer cells. As the phenomenon did not occur when the same lymphocytes were co‐cultivated with autologous fibroblasts, the generation of non‐specific effector cells may have been caused by specific antigenic triggering. The presence of autologous serum during „education”︁ was found to inhibit the manifestation and/or the generation of killer cells. The same serum was without effect when added during the cytotoxicity assay only.
Expression of virus‐associated antigens and immune cell functions during spontaneous regression of the friend viral murine leukemia
Authors: Cerny Jan , Essex Myron , Rich Marvin A. , Hardy W. D. 
Published: February 2007

AbstractSpontaneous regression and/or remission of Friend virus (FV)‐induced splenic erythroblastic leukemia was observed in CD‐1 mice infected with several isolates of FV. Regression of splenic tumor was accompanied by the loss of both specific FV‐induced cell membrane antigen (FVMA) and virus group‐specific antigens (gsa) from the spleen cells. The frequency (percentage) of immunoglobulin‐positive cells (B) and thetapositive cells (T) in the spleen was markedly decreased during leukemia progression, but there was a subsequent increase during regression. The appearance of gsa‐positive (gsa+) cells in peripheral blood correlated well with the early progressive and regressive phase of leukemia (up to 7 weeks after infection). Later, the presence of these cells became unpredictable in regard to status of disease. Gsa+ blood cells reappeared in most mice with regressed splenic tumors, suggesting persistence of the virus complex in the animals. Antibody responsiveness as determined by the numbers of hemolytic plaqueforming cells, PFC, after a single immunization with sheep red blood cells (SRBC), was suppressed in leukemia progression and recovered, spontaneously, during regression of leukemia. However, hemolytic PFC elicited by antigen in both progressors and regressors expressed the specific virus‐induced membrane antigen, FVMA, detectable by the PFC‐inhibition test with specific antiserum and complement. Recovery of immunological responsiveness also included the spontaneous appearance of virus‐neutralizing antibody to FV. However, this was not paralleled by the appearance of antibody to FVMA. Traces of anti‐FVMA antibody activity were occasionally detectable in serum of both progressors and regressors and did not correlate with virus neutralization, in individual mice. This may explain the susceptibility of regressors to secondary relapse and to reinfection.
The occurrence of tumours in f1, f2 and f3 descendants of bd rats exposed to n‐nitrosomethylurea during pregnancy
Authors: Tomatis L. , Hilfrich J. , Turusov V. 
Published: February 2007

AbstractN‐nitrosomethylurea (NMU) was administered once IP at a dose of 20 mg/kg to BD female rats on the 18th day of pregnancy. The first generation descendants (F1) were mated to produce a second generation (F2), which were then mated to produce a third generation (F3). While F1 rats were exposed directly to NMU during intrauterine life, it can be reasonably excluded that F2 and F3 descendants were exposed to NMU or its metabolites. F2 and F3 rats received no other treatment and untreated rats served as controls. Kidney and nervous‐tissue tumours were observed in F1 descendants and, with a lower incidence, in F2 descendants. In F3 rats, tumours of nervous tissue, but not of kidneys, were observed. These results confirm previous observations that exposure to a carcinogen during prenatal life results in an increased cancer risk which may persist for more than one generation.
The influence of different isolation procedures and the use of target cells from melanoma cell lines and short‐term cultures on the non‐specific cytotoxic effects of lymphocytes from healthy donors
Authors: De Vries Jan E. , Meyering Mary , Van Dongen Anneke , Rümke Philip 
Published: February 2007

AbstractIn parallel studies the effects of FHL1 and PNL on plated melanoma cells from cell lines and short‐term cultures were compared. FHL showed more frequent and also stronger cytotoxic and/or growth‐inhibiting effects than PNL. On melanoma target cells from cell lines both FHL and PNL showed more frequent and stronger cytotoxic and/or growth‐inhibiting effects than on melanoma target cells from short‐term cultures. In the individual donors the percentage of monocytes and EAC‐rosette‐forming cells in FHL was significantly higher than in PNL. A significant correlation was found between multiplication of the melanoma target cells during the test period and an increased susceptibility towards lymphocytes from healthy donors. Melanoma target cells from cell lines were not more fragile, or more susceptible to unfavourable culture conditions than cells from short‐term cultures, since non‐lymphocytic „effector”︁ cells showed much weaker cytotoxic and/or growth‐inhibiting effects than lymphocytes from healthy donors. Cytotoxic effects of lymphocytes from healthy donors were also registered on target cells from a mammary carcinoma and an osteosarcoma cell line. No significant differences in the cytotoxic effects of lymphocytes from healthy donors were observed when tested on mycoplasma‐contaminated melanoma cells and the same cells made mycoplasma‐free. Mitomycin‐C‐treated lymphocytes retained their cytotoxic effects. Lymphocytes from a healthy donor tested on different occasions on the same melanoma cells from a short term culture showed an incidental cytotoxic reaction.
Chorioallantoic membrane heterotransplantation of human brain tumors
Authors: Vogel Harold B. , Berry Richard G. 
Published: February 2007

AbstractSpecimens of human tumors were taken from the operating room and directly heterotransplanted to chick chorioallantoic membranes. Seventy‐one percent of the eggs survived the procedure and 41% of the tumors appeared viable after 1 week. Micro scopically, the first‐generation heterotransplants resembled the parent tumors. Many specimens showed evidence of growth, but in most of them there was also some degree of necrosis. The necrosis increased with serial heterotransplantation, so that tumor propagation usually was not possible beyond the second to third transplant generation; nevertheless, it was found that almost any histological type of intracranial tumor could be grown for short periods of time at least on the chick chorioallantoic membrane.
Growth stimulation of tumor cells in diffusion chambers implanted in mice bearing chemically induced tumors
Authors: Vaillier D. , Donner M. , Burg J. Vaillier Et C. 
Published: February 2007

AbstractThe growth of target tumor cells in diffusion chambers implanted subcutaneously into normal mice and into mice bearing chemically‐induced tumor was studied. It was observed that target‐cell multiplication was heavier in mice bearing a tumor less than 20 mm in diameter than in normal mice. In contrast, there was no growth difference between normal mice and mice bearing tumors with a diameter superior to 20 mm. This effect was observed when the target cells were of the same origin as the tumor borne by the mice. When the origin of tumors was different, the multiplication of target cells was stimulated but to a lesser degree. This phenomenon was observed in three out of four tested tumors. If the mice were irradiated with 500 R before tumor grafting and implantation of the diffusion chamber, the stimulation was still fully observable. In contrast, implanting the diffusion chambers intraperitoneally instead of subcutaneously or, alternatively, subcutaneously but far from the tumor, suppressed the stimulation. Also, no stimulation was observed if the grafted tumor was irradiated lethally or if a local inflammation was created by injection of bentonite or Freund's adjuvant. Tumor excision just before implantation of the chamber suppressed the stimulatory effect. Since the diffusion chambers are impermeable to cellular penetration it is concluded that the interstitial fluid of some tumor‐bearing mice contains diffusible factors capable of stimulating the multiplication of tumor target cells, close to the tumor.
Erythropoietin‐independent erythroid colony formation in vitro by hemopoietic cells of mice infected with friend virus
Authors: Liao Shuen‐Kuei , Axelrad Arthur A. 
Published: February 2007

AbstractWe have investigated the production of erythroid colonies in plasma culture by bone‐marrow and spleen cells taken form C3Hf/Bi mice previously infected with a polycythemic strain of Friend virus (FV). Inclusion of erythropoietin (Epo) in the medium was found unnecessary for erythroid colony formation in vitro by these cells, although it was essential for the production of erythroid colonies by hemopoietic cells from normal animals. Development of erythroid colonies also proceeded unimpeded when cells from FV‐infected animals were cultivated in medium pretreated with rabbit antiserum that was shown to inactivate Epo. Thus, the hemopoietic tissues of FV‐infected mice contained erythroid colony‐forming units (CFU‐Es) which appeared to be Epoindependent. When spleen cells from FV‐infected mice were exposed to antiserum directed against syngeneic FV‐infected spleen cells and complement, and then cultured with or without Epo, the number of erythroid colonies that developed was drastically reduced, indicating that the CFU‐Es in these animals carried FV‐induced antigen(s), and must themselves have been infected with virus. Electron microscopy of erythroid colonies produced by cells from FV‐infected mice revealed the presence of budding and abundant free type‐C virus particles. The efficiency of erythroid colony formation in vitro either with or without Epo by hemopoietic cells from FV‐infected mice was substantially increased over that of cells from normal mice. The increase in the number of CFU‐Es in these animals was due mainly to an increase in the number of Epo‐independent CFU‐Es. Epo‐independent CFU‐Es were first detected in bone marrow and spleen as early as 3 days after FV infection: thereafter their numbers progressively increased for at least 9 days. Hypertransfusion with red blood cells prior to FV infection reduced, while bleeding greatly increased, the efficiency of erythroid colony formation without Epo by cells from the spleens of the infected mice. The phenomenon of erythroid colony formation in plasma cultures lacking Epo provides a sensitive and reliable means of detecting Epo‐independent CFU‐Es, which appear to play a fundamental part in pathogenesis of the disease resulting from infection with the polycythemic strain of FV.
Expression of sv40 t antigen during the cell cycle of SV40‐transformed cells
Authors: Stenman Svante , Zeuthen Jesper , Ringertz Nils R. 
Published: February 2007

AbstractThe expression of the nuclear SV40‐induced T antigen was measured by micro fluorimetry on individual, asynchronously growing SV40‐transformed cells which had been stained with hamster T‐antiserum by the indirect immunofluorescence method. The same individual cells were first measured for T antigen and then for DNA by Feulgen microspectrophotometry. A linear correlation was observed between the two parameters. T antigen expression was also measured in cell populations arrested at different phases of the cell cycle. Results of both types of experiments show that the expression of the gene (s) for T antigen in transformed cells increases during DNA replication and reaches its highest level in G2 nuclei. During mitosis T antigen is found in the cytoplasm.
Dietary vitamin a and human lung cancer
Authors: Bjelke E. 
Published: February 2007

AbstractFive‐year follow‐up results for 8,278 men who in mail surveys had reported their cigarette smoking and dietary habits showed: (1) an index for vitamin A intake to be negatively associated with lung cancer incidence at all levels of cigarette smoking; (2) this association to be more clearly expressed in the subset of histologically proven pulmonary carcinomas other than adenocarcinoma; and (3) the positive association between cigarette smoking and lung cancer to obtain irrespective of the dietary level of vitamin A or related factors. The findings are in accordance with experimental results on animals and call for further exploration of the role of nutritional factors in the development of human lung cancer.
Surface markers on human b and t lymphocytes. VI. Cytotoxicity against cell lines as a functional marker for lymphocyte subpopulations
Authors: Jondal Mikael , Pross Hugh 
Published: February 2007

AbstractThe spontaneous lymphocyte‐mediated cytotoxicity (SLMC) of cells from normal donors against 19 different established cell lines was analysed. All normal lymphocytes were cytotoxic in all combinations tested in a 17 h 51Cr release assay. SLMC was found to be mediated by a minor subpopulation of lymphocytes with Fc/C3 receptors. Noncytotoxic SRBC binding T‐lymphocytes could be induced to become cytotoxic by the addition of Con A to the incubation medium. SLMC and lectin‐induced cytotoxicity were briefly characterized. It is argued that SLMC is a non‐specific non‐immunological reaction which must be taken into consideration when lymphocytes from cancer patients are tested against tumour‐cell lines in vitro. Furthermore, SLMC and lectin‐induced cytotoxicity are proposed as functional markers for Fc/C3‐binding lymphocytes and SRBC binding lymphocytes respectively.
Studies of epstein‐barr virus (ebv)‐associated nuclear antigen. I. Assay in human lymphoblastoid cell lines by direct and indirect determination of 125i‐igg binding
Authors: Brown T. D. K. , Ernberg I. , Klein G. 
Published: February 2007

AbstractA quantitative assay for EBNA in human lymphoblastoid cell lines has been developed. The assay employs EBNA‐positive and ‐negative 125I‐IgG preparations as reagents and can be used in a direct or indirect manner. EBNA specificity has been demonstrated in a number of ways. The antigenic relationship between EBNA present in Raji cells and in a number of other human lymphoblastoid cell lines of diverse origins and between the cell‐associated antigen present in FT Raji cells and that present in isolated Raji nuclei has been studied. The possibility of carrying out blocking titrations for anti‐EBNA determination has been demonstrated and the effect of glutaraldehyde and formaldehyde upon antigenic activity in FT Raji cells has been studied.
Serum factors modifying cell mediated immunity to rat hepatoma D23 correlated with tumour growth
Authors: Bowen J. G. , Robins R. A. , Baldwin R. W. 
Published: February 2007

AbstractSera from rats bearing a progressively growing transplanted aminoazo‐dye‐induced hepatoma (hepatoma D23) have been examined for the presence of hepatoma D23‐specific antigen, antibody and immune complexes throughout the course of tumour growth. The levels of these factors have been correlated with the in vitro blocking and inhibition of cytotoxic lymph‐node cells from immunized animals for cultured tumour cells. Sera from animals bearing small tumours (7–14 days after tumour implantation) contain free tumour‐specific antigen whilst immune complexes could not be detected. Although these sera were neither blocking nor inhibitory under the normal conditions of the test, when concentrated two and fourfold, inhibition but not blocking of lymph‐node cell cytotoxicity could be detected. In comparison sera from animals bearing large tumours (24–28 days) blocked but did no inhibit in vitro lymph‐node cell cytotoxicity and this correlates with the presence of tumour‐specific immune complexes in antibody excess. Animals with intermediate‐sized tumours had high levels of both blocking and inhibitory activity in the serum, these effects becoming apparent when neither free antibody nor free antigen could be detected. The relevance of these findings to the mechanism by which a growing tumour may escape specific cellular immune destruction is discussed.
An additional younger‐age peak for cancer of the nasopharynx
Authors: Balakrishnan V. 
Published: February 2007

AbstractThe age distribution of 666 masopharyngeal cancer patients attending the Tata Memorial Hospital, Bombay, during 1941–72 was found to show an additional younger‐age peak in the age‐group 13–22. The peak was found in both sexes, in different communities, at two time periods and in histologically proved cases. One hundred cases of nasopharyngeal lymphosarcoma showed no deviation from a uniform age distribution. Pooled incidence data for 48 population groups showed the peak in the age‐group 15–19 for males and in the age‐group 10–14 for females. No such peak was observed for malignancies of the nose, sinuses, etc. (ICD NO:160).
Anti‐tumor antibodies in normal mouse sera
Authors: Martin Sue Ellen , Martin W. John 
Published: February 2007

AbstractEvidence for the involvement of the immune system in surveillance against nascent tumors was sought by testing whether normal mouse sera were cytotoxic in the presence of rabbit complement for a variety of lymphoid and non‐lymphoid tumor‐cell lines. Tumor‐reactive antibodies were detected in all mouse sera tested, including sera from congenitally athymic (nude) mice. Considerable variation was noted, however, in the levels of naturally occurring antibodies against specific tumors. Anti‐tumor antibodies were identified as being predominantly IgM. The possible relevance of natural anti‐tumor antibodies to immune surveillance was discussed.
The effect of non‐ionic detergent tween 80 on colcemid‐resistant transformed mouse cells in vitro
Authors: Stavrovskaya A. A. , Potapova T. V. , Rosenblat V. A. , Serpinskaya A. S. 
Published: February 2007

AbstractThe effect of the non‐ionic detergent tween 80 on one colcemid‐resistant and one sensitive subline of mouse L cells has been studied. The colcemid‐resistant subline was also resistant to colchicine and Vinca alkaloids. Tween 80 at concentrations of 0.01% (v/v) or higher increased the sensitivity of drug‐resistant cells to the antimitotic effect of colcemid, colchicine and vinblastine. Tween 80 also potentiated the initial rate and the maximal level of the (3H)‐colchicine uptake by both sensitive and resistant cells. However, the detergent at concentrations of up to 1% had no effect on (3H)‐colchicine binding by cell homogenates. Thus it appears that the effects of tween 80 were due to an increase in cell membrane permeability to the drugs. The effect was completely reversible. The cells did not become adapted to the sensitizing action of tween 80 even after prolonged incubation in medium containing the detergent. A considerable increase in the permeability to the drug was obtained with doses of tween 80 which were non‐toxic and which had no effect on cell proliferation, morphology and locomotion. The increase in membrane permeability caused by tween 80 at these concentrations was selective, the membrane permeability to ions and to (3H)‐2‐deoxy‐D‐glucose being, in fact, unchanged.
Control of nuclear division in SV40 and adenovirus type 12 transformed mouse 3T3 cells
Authors: O'Neill Frank J. 
Published: February 2007

AbstractUntransformed, non‐tumorigenic mouse cells respond to cytochalasin B (CB) with limited nuclear division. BALB/c mouse embryo fibroblasts (MEF) and both BALB/c 3T3 and Swiss 3T3 cells become binucleated in the presence of CB and cells with three or more nuclei are very rare or undetectable. MEF are diploid (40 chromosomes) and 3T3 cells are subtetraploid (74–76 chromosomes). Transformation of MEF by SV40 produces a dramatic change in response to CB. These cells, which contain SV40 T‐antigen, become highly multinucleated in the presence of CB. More than 20% of the cells have at least seven nuclei. Also premature chromosome condensation (PCC), an abnormality rare in CB‐treated normal cells but one which is common to highly multi‐nucleated cells, is frequent and occurs in at least 10% of mitoses. SV40‐transformed MEF have 40 or 80 chromosomes, e.g. are diploid or tetraploid. Transformation of 3T3 by SV40 or adenovirus type 12 does not result in a marked change in the response to CB. Although some trinucleate and tetranucleate cells are formed, cells with more nuclei are undetectable or rare. PCC is also rare. These cells show chromosome numbers somewhat lower than their untransformed parents and in one line the chromosome number appears to decrease with passage of the cells. This failure to undergo a marked change in responsiveness to CB following transformation is not a characteristic of all transformed 3T3 cells. SVT2, a line of 3T3 which was transformed by SV40 prior to its establishment as a continuous line, responds to CB with a high degree of multinucleation. These cells are diploid. These results suggests that 3T3 cells are constitutive for controlled nuclear division and that this feature may be related to chromosome constitution.
Isolation and characterization of a homogeneous isomeric species of carcinoembryonic antigen: CEA‐S
Authors: Plow Edward F. , Edgington Thomas S. 
Published: February 2007

AbstractA single homogeneous isomeric species of carcinoembryonic antigen was isolated by reference to solubility in 0.9 M perchloric acid, isoelectric focusing, molecular exclusion chromatography, ion exchange chromatography, passage through immunoabsorbants, and isopyknic density gradient ultracentrifugation. The final product, representing approximately 1.8% of the perchloric acid soluble glycoprotein of the tumor, is homogeneous and devoid of other proteins by polyacrylamide gel electrophoresis. This single species of carcinoembryonic antigen, CEA‐S, has a sedimentation velocity of 6.6, a diffusion constant of 3.05 × 10−7 cm2/sec, a mean Stokes radius of 65 Å, a density of 1.41 ml/g in cesium chloride and an estimated molecular weight of 181,000, and it is devoid of detectable A or B blood‐group antigens. Immunochemical studies demonstrate qualitative similarities between CEA‐S and conventional carcinoembryonic antigens; however, competitive inhibition analyses demonstrate significant quantitative immunochemical differences between CEA‐S and preparations of carcinoembryonic antigen. These results are consistent with the concept that CEA‐S is an immunochemical isomer of carcinoembryonic antigen.