bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sequential studies on cell‐mediated tumor immunity and blocking serum activity in ten patients with malignant melanoma
Authors: Hellström I. , Warner G. A. , Hellström K. E. , Sjögren H. O. 
Published: February 2007

AbstractTen human patients with malignant melanoma were followed with respect to two in vitro parameters of tumor immunity, the ability of the patients' blood lymphocytes to destroy cultivated melanoma cells, and the ability of the patients' sera to block such destruction, and with respect to changes in the clinical status, such as increases or decreases in detectable tumor mass. Allogeneic and (to a much lesser extent) autochthonous melanoma cells were used as targets. The degree of lymphocyte‐mediated tumor immunity was higher in patients with little or no residual tumor than in patients with large tumor loads, although the latter patients were also found to be reactive. Sera from patients with clinically detectable melanoma could block the cytotoxic lymphocyte effect, as could sera from patients who developed melanoma shortly after the serum harvest. Disappearance of blocking serum activity was seen to accompany clinical improvement. Sera from some patients without clinically detectable tumor could potentiate the cytotoxic effect of lymphocytes from melanoma patients. The findings support the view that cell‐mediated tumor immunity and blocking serum activity, as studied in vitro, are important correlates of the patients' immunological defense against their tumors in vivo, and they suggest that monitoring of these parameters may be prognostically useful. They also suggest that procedures capable of improving cell‐mediated tumor immunity without increasing blocking serum activity may be therapeutically beneficial.
Multiple tumors in the pericardial cavity of an australian rock oyster, crassostrea commercialis (iredale and roughley)
Authors: Dinamani P. , Wolf Peter H. 
Published: February 2007

AbstractA pedunculated tumor within the pericardial cavity of a Sydney rock oyster (Crassostrea commercialis) was discovered during a routine dissection. The tumor measured 5 × 4.8 × 4.5 mm, was lobulated and was attached to the dorsal parietal pericardium over the ventricle, close to the anterior aorta. Associated with it were three smaller nodular lesions, also on the parietal pericardium. All four masses were composed chiefly of vesicular connective tissue (Leydig cells of oysters) within which mild inflammatory cell infiltration and fibrosis were present. The mesothelium overlying or enveloping the tumors was moderately hyperplastic. These apparently multicentric lesions present a problem in differential diagnosis among (1) slow‐growing, multi‐centric, benign neoplasms of Leydig cell origin, (2) developmental anomaly, including hamartoma, (3) hyperplasia secondary to inflammation and repair. The authors consider the first of these possibilities to be the most acceptable. The tumors in this specimen appear to belong in a group with three similar ones previously recorded in the literature. Their precise nature in relation to neoplastic processes remains unsettled.
Ultrastructural distribution of concanavalin‐a receptors on hamster embryo and adenovirus tumour cell cultures
Authors: Rowlatt C. , Wicker R. , Bernhard W. 
Published: February 2007

AbstractAn electron microscope cytochemical reaction, based on the specificity of concanavalin A for certain sugar residues, was used to study the surface coat of cells in cultures of an Adenovirus 12 hamster tumour cell line (TAd12 XIV), of cell strains from other hamster tumours induced by simian Adenovirus 7 (SA7) and of secondary cultures of normal hamster embryo cells. When the reaction was performed on living cells, in situ in the bottles in which they had been grown, a uniform surface coat of positive material was found on the normal embryo cells. The tumour cells were also positive, but the reaction product had a tendency to be more patchily distributed over the surface. This discontinuity of the labelling was particularly pronounced in the strain TAd12 XIV, but was less visible in the highly malignant strains SA7. When the reaction was performed on cultures previously fixed with formaldehyde, no difference was found between the three types of cell cultures. Simple stereological analysis confirmed these findings. It was concluded that loss of material occurred differentially between the different types of culture during the stages of the reaction before fixation. The possibilities of this loss being due to physico‐chemical differences in the cell surface material or to underlying metabolic changes are discussed.
Relationship between the sensitivity of EBV‐carrying lymphoblastoid lines to superinfection and the inducibility of the resident viral genome
Authors: Klein George , Dombos Laszlo 
Published: February 2007

AbstractHuman, EBV‐carrying lymphoblastoid lines show wide differences in their sensitivity to superinfection with EBV concentrates and also in their sensitivity to the activation of the resident viral genome by BUDR and IUDR. A significant correlation was found between sensitivity to superinfection and activation in 23 virus‐receptor‐positive lines. In 10 receptor‐negative lines, there was no such correlation: they were resistant to superinfection since they could not adsorb the virus, but differed widely in their activatability. The findings suggest that the intracellular restrictive mechanism that limits superinfection in the receptor‐positive, resistant lines, can also restrict the function of the activated genome, derived from within. Since some of the lines that were resistant to both superinfection and activation were spontaneous producers, however, it appears that the same mechanism does not necessarily affect the “spontaneous” function of the resident genome.
Histologic characteristics of breast cancer in Boston and Tokyo
Authors: Macmahon Brian , Morrison Alan S. , Ackerman Lauren V. , Lattes Raffaele , Taylor Herbert B. , Yuasa Shu 
Published: February 2007

AbstractHistologic slides from representative series of breast cancer patients in Boston, where the incidence rate of breast cancer is high, and in Tokyo, where the incidence rate is low, were reviewed by pathologists who did not know the city of origin of the material. Intraductal, medullary and colloid histologic types were relatively more frequent in Tokyo. Also more frequent in Tokyo were tumors with circumscribed margins and a high degree of cellular reaction. Tumors of small‐cell or invasive ductal histologic type and tumors with a high degree of fibrosis were more frequent in Boston than in Tokyo.
Temperature‐dependent alterations in 2‐deoxyglucose uptake in rat cells transformed by a cold‐sensitive murine sarcoma virus mutant
Authors: May J. T. , Somers K. D. , Kit Saul 
Published: February 2007

AbstractCells transformed by Moloney sarcoma virus (MSV) take up 2‐deoxyglucose at a faster rate at 39° C than uninfected or Moloney leukemia virus (MoLV)—infected normal rat kidney (NRK) cells. In a sarcoma‐virus‐transformed cell line, NRK (MSV‐lb), whose transformed phenotype is expressed at 39° C (permissive) but not at 33° C (non‐permissive), the stimulation of 2‐deoxyglucose uptake at 39° C is temperature dependent; the increase is observed when cells are grown at 39° C but not at 33 C. When these cells were shifted from the non‐permissive to the permissive temperature, the uptake increased from a rate near that of uninfected cells to a rate half that of NRK cells infected with Moloney sarcoma‐leukemia complex (MSV‐MoLV). The reverse change occurred when the cells were shifted from the permissive to the non‐permissive temperature. Thus in a sarcoma virus‐infected rat cell line where the maintenance of the transformed state is dependent on a cold‐sensitive viral function, the uptake of 2‐deoxyglucose is reduced in the cold‐sensitive cells and correlated with the expression of the transformed phenotype.
Cell‐mediated immune reaction against tumors induced by oncornaviruses. II. Nature of the effector cells in tumor‐cell cytolysis
Authors: Leclerc J. C. , Gomard E. , Plata F. , Levy J. P. 
Published: February 2007

AbstractThe nature of the effector cells detected by the chromium release test (CRT) has been studied in BALB/c and C57Bl/6 mice bearing murine sarcoma virus (MSV)‐induced tumors. Anti‐θ‐C3H immune sera completely inhibited the cytotoxic activity of lymphoid cells in the presence of complement; anti‐immunoglobulin sera failed to decrease this activity. No activation of normal non‐sensitized lymphoid cells in the presence of heat‐decomplemented sera from mice bearing MSV‐induced sarcomas could be obtained. Identical results have been found in allogeneic systems with major H‐2 histocompatibility antigens. It can be concluded that a thymus‐processed lymphoid cell sub‐population sharing the θ antigen is exclusively or very predominantly responsible for the immune cytolysis both in syngeneic tumor systems and in allogeneic transplantation systems.
Localization of alpha‐fetoprotein in transplantable murine teratocarcinomas
Authors: Engelhardt N. V. , Poltoranina V. S. , Yazova A. K. 
Published: February 2007

AbstractEmbryo‐specific serum component α‐fetoprotein (AFP) was localized by the indirect immunofluorescent technique on paraffin sections of transplantable teratocarcinoma of strain 129/SV‐S1 CP mice. AFP was found in several types of structures comprising an insignificant part of the total section area. Most frequent and bright AFP‐specific fluorescence occurred in the epithelium of endodermal origin lining cysts and tubules; in addition, AFP was found in sheets of cells, groups or individual cells of non‐identified origin and in squamous epithelium arranged in pearls. In cysts and granules isolated from the ascitic fluid, developing after an intraperitoneal injection of teratocarcinoma suspension, AFP was found in cells of the external layer, very similar to those of the visceral yolk sac, and in the embryotype mesenchyme inside the cysts. By analytical disc‐electrophoresis in polyacrylamide gel, cysts were found to contain albumin, AFP, transferrin and gamma‐globulin, the relative proportion of AFP being considerably higher than in the ascitic fluid as compared with the other proteins mentioned. It is suggested that AFP localization in teratocarcinomas corresponds to the sites of its synthesis in the embryo and that AFP synthesis is a specific function of certain forms of endodermal differentiation.
Common avian oncornavirus‐induced tumor antigens in different species as revealed by immuno‐ferritin techniques
Authors: Gelderblom Hans , Bauer Heinz 
Published: February 2007

AbstractThe application of avian RNA tumor virus (ATV)‐neutralizing chicken sera to ATV‐transformed mammalian cells followed by indirect immuno‐ferritin labelling revealed an ATV group‐specific cell membrane labelling in two mouse cell lines. The respective antigens seem to be cross‐antigenic to the tumor‐specific surface antigen (TSSA) demonstrated recently on ATV‐transformed chicken embryo cells. The common antigens do not represent ATV envelope antigenicities or any of the other characteristized virus structural components.
Persistence of rous sarcoma virus in transformed non‐permissive cells: Characteristics of virus induction following sendai virus‐mediated fusion with permissive cells
Authors: Vigier Philippe 
Published: February 2007

AbstractVirus induction in heterokaryons formed by non‐permissive cells transformed by Rous sarcoma virus (RSV) and permissive chick embryo (CE) cells, in the presence of inactivated Sendai virus, was studied with a clone of hamster BHK21 fibroblasts transformed by Schmidt‐Ruppin strain RSV (clone RS2) and subclones derived from this clone. The main results have been the following: (1) The number of heterokaryons giving rise to foci of Rous cells (focus‐forming infective centers, or FFICs) in mixed cultures is proportional to the number of RS2 cells when the initial CE:RS2 cell ratio attains 30, and almost all heterokaryons are then formed from single RS2 cells. (2) Recovery of FFICs also depends on the dose of Sendai virus. (3) Following fusion of RS2 cells with cells from different chick embryos the recovery of FFICs varies in parallel with the number of foci produced by free virus in cultures of these embryos. (4) The latent period of virus induction from the time of cell fusion is about 24 h, and somewhat longer than that of viral replication in newly infected CE cells. The growth of induced virus is similar to that of virus produced after de novo infection. (5) Virus induction requires no DNA synthesis but is inhibited, reversibly, by treatment for a few hours with inhibitors of DNA‐dependent synthesis (actinomycin D) and protein synthesis (puromycin and cycloheximide). Hence, non‐permissiveness of RS2 cells may be due to a partial block of transcription of the viral replicative DNA (provirus) present in the cells, and induction in heterokaryons to switching from partial to full transcription and translation of the provirus. However, it is also possible that some function, or factor (s) of the CE cells is required for virus production in heterokaryons. (6) The study of a subclone of RS2 cells 100‐ to 1000‐fold less inducible than other subclones suggesting that, in this subclone, non‐permissiveness may be due to a permanent block of synthesis of all viral proteins, at the level of transcription of the provirus.
Inhibition of hepatoma‐immune lymph‐node cell cytotoxicity by tumour‐bearer serum, and solubilized hepatoma antigen
Authors: Baldwin R. W. , Price M. R. , Robins R. A. 
Published: February 2007

AbstractSera from rats bearing transplanted aminoazo‐dye‐induced hepatomas inhibited the cytotoxicity of lymph‐node cells from tumour‐immune rats for plated hepatoma cells, when the sera were incubated with the effector cells, rather than target cells. In contrast, sera from hepatoma‐immune rats, which have previously been shown to block lymphocyte cytotoxicity at the level of the target cell, failed to inhibit lymph‐node cell cytotoxicity when pre‐incubated with the effector cells. The possibility that antigenic determinants could be responsible for lymphocyte inhibition is supported by the demonstration that papain‐solubilized hepatoma‐specific antigen preparations inhibited lymph‐node cell cytotoxicity. The role of specific antibody, antigen and immune complexes in the interaction between cellular immunity and humoral factors during tumour growth is discussed.
In utero tumor induction by murine sarcoma virus (moloney) in the rat. II. Histological and ultrastructural characteristics
Authors: Sobis H. , Vandeputte M. 
Published: February 2007

AbstractOn histological examination the twelve MSV‐induced tumors in the uterus observed in our study proved to be of fetal origin. Ten of the 12 tumors had the histological and ultrastructural characteristics of a yolk‐sac tumor. The two other tumors examined had a different morphological structure. One was classified as a teratoma with embryonal carcinoma, the other as a carcinosarcoma. In the primary neoplasms virus particles were found. Their ultrastructure was similar to that of MSV. The histology and the electron microscopy results are discussed in relation to the morphogenesis and the occurrence of these tumors in rodents as well as in man.
Chromosomal control of malignancy in tumors from cells transformed by polyoma virus
Authors: Yamamoto Toshiyuki , Hayashi Makoto , Rabinowitz Zelig , Sachs Leo 
Published: February 2007

AbstractThe chromosome banding pattern has been analyzed in clones of male and female golden hamster cells independently transformed by polyoma virus and tumors derived from these cells. All the tumors showed either a loss of a piece of chromosome 53 or a gain of a piece or a whole chromosome of 56. An additional 72 chromosome in one line of transformed cells was lost in the tumors derived from this line. The results support our gene balance model of malignancy and indicate that genes of expression of malignancy in these cells were located on chromosome 56 and that genes for suppression of malignancy were located on a piece of chromosome 53 and on chromosome 72. All transformed lines and their tumors showed a loss of a piece of one or both × chromosomes in male and female cells, respectively. This loss of a piece of X chromosome was also found in non‐malignant revertants from polyoma‐transformed cells, so that this change in the X chromosome was not specific for malignant cells.
Correlation between various cell‐surface antigens induced by murine leukemia virus in the rat: Serological analysis
Authors: Kuzumaki Noboru , Takeichi Noritoshi , Sendo Fujiro , Kodama Takao , Kobayashi Hiroshi 
Published: February 2007

AbstractAnalysis based on the cytotoxicity test using antisera produced in rats indicated the presence of various cell‐surface antigens on the tumors in WKA/Mk rats induced or artificially infected by Friend, Rauscher or Gross viruses. Each line of the tumor was found to have a common antigen, namely group‐specific cell‐surface antigen. A Gross type‐specific and Friend and Rauscher type‐specific cell‐surface antigens were also detected, in keeping with the observations in the mouse system. In addition, the present experiments strongly suggested that a Friend strain‐specific antigen was detected only on the cell‐surface of the tumors in WKA/Mk rats induced or artificially infected by Friend virus. These results were in parallel with the data of previously reported transplantation studies.
Spontaneous and induced production of endogenous type‐C RNA virus from a clonal line of spontaneously transformed BALB/3T3
Authors: Lieber Michael M. , Todaro George J. 
Published: February 2007

AbstractThis report describes the different levels of expression of the endogenous type‐C viral genome in a spontaneously transformed, tumor‐producing clone (S16) derived from the BALB/3T3 murine cell line. Four of nine subclones of S16 were found to continuously release high titers of endogenous virus. Five other S16 subclones were virus‐nonproducers, but could be readily induced with 5′‐bromodeoxyuridine to release large quantities of the endogenous virus. The transformed subclones were much more readily induced to produce virus compared to the parent BALB/3T3 cell line. All virus‐producing subclones and one non‐virus‐producing subclone contained considerably larger quantites of the major group‐specific antigens of the mouse type‐C viruses than did the untransformed BALB/3T3 cells themselves. Kinetics of induction of type‐C virus was studied in two clones that did not spontaneously release virus. Extracellular viral polymerase could be detected within 24 h of BrdU application; it increased exponentially over a thousand‐fold range during the next 48 h, and then slowly declined. Thus, the probability of expression of the endogenous type‐C viral genome is increased in spontaneously transformed BALB/3T3 cells.
The development and specific suppression of concomitant immunity in two syngeneic tumour‐host systems
Authors: Chandradasa K. D. 
Published: February 2007

AbstractImmunological resistance, concomitant with tumour growth, against two methyl‐cholanthrene‐induced murine sarcomas MC23 and MC6 differing widely in their immunogenicities, was studied in inbred C57BL and BALB/c strains of mice which are syngeneic with the respective tumours. It was found that, initially, immune responses to specific transplantation antigens resulted in a peak of antitumour resistance at 10–14 days after the implantation of the tumours. In the second phase of tumour growth a rapid decline of the resistance was observed. The peak at 10–14 days was followed by a greater than 50% loss of resistance to re‐inoculation with the tumour cells, 1 week later. Further decline of resistance in the MC6‐BALB/c system was followed by the acceptance and progressive growth of over‐threshold doses of tumour cells. A comparable observation could not be made in the immunogenically weaker MC23‐C57BL system where further loss of resistance was gradual. The above changes in the development and decline of anti‐tumour resistance were broadly correlated with the progress of the immunoblast reaction of the paracortical areas of regional lymph nodes. Changes of anti‐tumour resistance in the MC6‐BALB/c system were found to be associated with corresponding changes in the availability and/or effectiveness of specifically cytotoxic lymphoid cells, in the lymphoid organs, as well as a change in the quality of the serum factors from weakly inhibitory to mildly enhancing, in the tumour. Specifically cytotoxic lymphoid cells could not be demonstrated in the MC23‐C57BL system by the lymphocyte neutralization technique employed, possibly due to the involvement of in vivo blocking phenomena. Accordingly, sera of these mice proved to be tumour‐enhancing throughout the period of tumour growth. It is suggested that the progressive growth of the tumours is facilitated by the specific suppression of cell‐mediated immunity by the “efferent” as well as by the “afferent” mechanisms and is brought about by a factor or factors–possibly antibody and/or antigen‐antibody complexes–present in the serum of the tumour‐bearing mice.
Influence of cultivation, trypsinization and aggregation on the transplantability of melanoma B16 cells
Authors: Hagmar Björn , Norrby Klas 
Published: February 2007

AbstractTo elucidate the usefulness of tumour cells grown in vitro for transplantation studies, Melanoma B16 was grown in monolayer culture. Three types of suspensions were prepared from the cell cultures: two virtually monocellular suspensions, one produced by mechanical procedures and Versene (CV), the other with the addition of trypsinization (CTV); a third suspension containing cell aggregates (CVA) was produced by centrifuging a CV suspension. For comparison, a well‐dissociated suspension of solid tumor origin was prepared by a trypsin‐Versene procedure (STV). All suspensions were characterized with regard to dissociation grade, cell volumes and cellular electrophoretic mobility and were transplanted in graded cell doses subcutaneously, intraperitoneally and intravenously. While inoculum‐doses needed for progressive growth were lower IP than SC, the transplantabilities were similar in these sites for all suspensions, indicating similar viabilities and absence of major dilution errors. The growth patterns for IV infused cells exhibited significant differences between the suspensions. CV cells gave rise to lung tumours almost exclusively, while CVA animals, in addition to a large total lung tumour volume, had some extrapulmonary takes. CTV had the greatest number of extrapulmonary tumours, but in combination with small lung tumours, STV cell recipients were intermediate with respect to pulmonary as well as extrapulmonary tumours. These observations were collated with data regarding aggregation, cell volumes and electrophoretic mobility. It was concluded that (1) cultivated tumour cells can have similar transplantation characteristics to the tumour of origin; (2) such cells may be useful in tumour dissemination studies; (3) trypsinization as well as the presence of cell aggregates affects the growth pattern of IV infused tumour cells by yielding an increased extrapulmonary tumour crop.