bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of lymphoid cell lines established from multiple epstein‐barr virus (EBV)‐induced lymphomas in a cotton‐topped marmoset
Authors: Rabin Harvey , Neubauer Russell H. , Hopkins Ralph F. , Levy Barnet M. 
Published: February 2007

AbstractInoculation of a cotton‐topped marmoset with cell‐free EBV, strain B95‐8, resulted in the induction of lymphomas in liver, spleen, and mesenteric lymph nodes. Continous suspension cell lines were established from tumor tissue from each of these three sites. Cells of each line were positive for intracellular EBV antigens and EB nuclear antigen and released low levels of transforming virus. Early after initial culturing each line had a high frequency of cells (84‐85%) with receptors for activated complement but these receptors were no longer evident on retesting several months later. All three lines initially showed high levels of cells which stained for surface lambda light chain and gamma and mu heavy chains. Cells of all three lines showed a decrease in gamma chain staining and the lymph‐node tumor line showed reductions in surface staining for mu and lambda chains as well after prolonged cultivation. Clonal cells of the three lines resembled their respective parental lines in surface markers. Cytogenetically, all the lines were hypodiploid, 2n = 45, and several karyotypes from all three lines showed the loss of a medium‐sized metacentric chromosome. A marker chromosome with an extra band in the centromeric region was apparent in the lymph‐node tumor line. These results indicate that cells of individual tumors in a cotton‐topped marmoset with multiple EBV‐induced lymphomas are similar to each other in a number of characteristics although a certain degree of divergence was observed. Thus, it is possible that EBV‐induced lymphomas in cotton‐topped marmosets may have a common cell origin as is the case with Burkitt lymphoma in humans.
SV40 tumor rejection induced by vesicular stomatitis virus bearing SV40 tumor‐specific transplantation antigen (SV40‐TSTA). I. Specificity of immunoprotection and effect of enzyme treatment on tsta activity
Authors: Ansel Sandra , Huet Christian , Tournier Paul 
Published: February 2007

AbstractHighly purified vesicular stomatitis virus (VSV) was obtained from VSV‐infected SV40‐transformed hamster cell lines. Immunization with this virus protected hamsters against challenge with SV40‐transformed cells (TSV5‐cl2). This protection was obtained regardless of the source of the SV40‐transformed cells (e.g. cat, rat, hamster) used to produce VSV, and was therefore associated with the SV40 tumor‐specific transplantation antigen (SV40‐TSTA). Furthermore, when grown on spontaneously transformed cell lines or on cells transformed by a different oncogenic DNA virus, such as polyoma virus, the VSV failed to protect against the SV40‐induced tumor. It was concluded that the SV40‐TSTA activity of purified VSV is due to the incorporation of SV40‐TSTA within the viral envelope. When VSV was treated with proteolytic enzymes (bromelain, trypsin) no loss of TSTA‐induced tumor rejection was observed, although VSV had lost its ability to induce virus‐neutralizing antibody. This clearly demonstrates that the TSTA activity is not related to the viral spikes. Phospholipase C suppressed the TSTA activity but neutralizing activity was still detectable in the anti‐VSV sera. The results presented here demonstrate that the protection afforded by VSV is highly specific. It is particularly interesting that SV40‐TSTA activity may be conveyed by the lipid core of the viral envelope.
Susceptibility to and escape from complement‐mediated lysis of guinea‐pig hepatoma line‐10
Authors: Abe S. , Berczi I. , Sehon A. H. 
Published: February 2007

AbstractRabbit xenoantisera produced against diethyl‐nitrosamine‐induced strain‐2 guinea‐pig hepatoma line‐10 cells (L‐10) according to various immunization schedules were compared for their cytotoxicity on L‐10 cells in the presence of guinea‐pig complement. The highest activity was obtained with anti‐sera (Cx‐1) produced by repeated intravenous injections of living L‐10 cells at high cell dosage, whereas intramuscular injections of living or glutaraldehyde‐treated L‐10 cells at similar frequency and cell dosage were less effective for the production of cytotoxic antibodies against L‐10 cells. Intravenous injections of smaller cell doses were less effective. The cytotoxic antibody in Cx‐1 antiserum was shown to be IgG by various methods including gel filtration on Sephadex G‐200, ion exchange chromatography and immunoelectrophoresis of purified tumor‐specific antibodies. It was concluded that L‐10 cells can be lysed by guinea‐pig complement and tumor‐specific antibodies (IgG). Some antisera contained IgM antibodies which were not cytotoxic. A decrease in susceptibility of L‐10 cells to complement‐mediated lysis was observed when the cells were maintained in vivo for a long period (more than 20 passage generations). This was due to a lower density of tumor antigens on the cell surface. When tumor cells were treated with a second antibody directed against rabbit IgG or F(ab′)2, cytotoxicity of Cx‐1 antisera was completely abolished.
Human lymphoblastoid cell lines derived from individuals without lymphoproliferative disease contain the same latent forms of epstein‐barr virus dna as those found in tumor cells
Authors: Kaschka‐Dierich Christine , Falk Lawrence , Bjursell Gunnar , Adams Alice , Lindahl Tomas 
Published: February 2007

AbstractThe physical state of the intracellular Epstein‐Barr virus DNA was characterized in four human lymphoblastoid cell lines, F‐265, NC‐37, U‐303 L, and PG‐1, derived from individuals without lympho‐proliferative disease. For comparison, a previously investigated Burkitt lymphoma line, Raji, and a more recently established cell line of that origin, Rael, were also studied. The techniques employed were CsCl density gradient centrifugation, glycerol gradient centrifugation, and ethidium bromide‐CsCl density gradient centrifugation in combination with nucleic acid hybridization, as well as electron microscopy contour length measurements of purified circular EBV DNA. All six cell lines contained multiple copies of covalently closed circular EBV DNA‐molecules of the same size, as well as viral DNA with the properties of integrated DNA. No differences could be detected between the forms of EBV DNA present in cell lines derived from non‐malignant sources and those present in lymphoma lines.
Differential sensitivity of Xeroderma pigmentosum cells of different repair capacities towards the chromosome breaking action of carcinogens and mutagens
Authors: San R. H. C. , Stich W. , Stich H. F. 
Published: February 2007

AbstractThe sensitivity of cultured fibroblasts obtained from four unrelated Xeroderma pigmentosum patients (XP‐K, XP‐C, XP‐E and XP‐H), which showed different DNA repair levels, was examined. The frequency of metaphase plates with chromosome aberrations and the frequency of breaks and exchanges per chromosome complement were estimated following exposure to the carcinogens 4‐nitroquinoline‐1‐oxide (4N QO), N‐acetoxy‐2‐acetyl‐aminofluorene (N‐acetoxy‐2‐AAF), and N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG), and to the mutagen daunomycin. The frequency of chromosome aberrations (breaks and exchanges) increased in the order (XP‐K < XP‐C < XP‐E < XP‐H) with decreasing DNA repair capacity of the XP cells examined (XP‐K > XP‐C > XP‐E > XP‐H) following 4N QO and N‐acetoxy‐2‐AAF. MNNG induced DNA repair synthesis and chromosome aberrations in the four XP cell types at levels comparable to those in fibroblasts of non‐afflicted persons. Daunomycin triggered no DNA repair synthesis but induced similar frequencies of chromosome aberrations in the XP cells and controls. Heterozygous XP cells from parents of XP‐K, XP‐E and XP‐C responded as control cells towards the three carcinogens and the mutagen used. Xeroderma pigmentosum can be considered to be an “induced” chromosome instability syndrome, in contrast to Bloom's syndrome or Fanconi's anaemia, which are “spontaneous” chromosome breakage syndromes according to German's definition.
Expression of alien h‐2 specificities on a chemically induced balb/c fibrosarcoma
Authors: Meschini Angela , Invernizzi Giovanni , Parmiani Giorgio 
Published: February 2007

AbstractThe presence of alien histocompatibility antigens on the cell surface of the 3‐methylcholanthreneinduced BALB/c (H‐2d) fibrosarcoma C‐1, was investigated by serological and transplantation studies. Absorption experiments with monospecific alloantisera showed that C‐1 cells expressed their original private (H‐2.4 and 31) and public (H‐2.3, 8, 28, and 35) specificities. C‐1 cells were also able to absorb monospecific antisera directed to the private specificity H‐2.23 of the H‐2k haplotype, as well as antisera to the public specificities H‐2.1, 5, 11 and 25 (H‐2k and in part H‐2q, H‐2a and H‐2b haplotypes), which are absent from H‐2d normal cells. Conversely, other alien specificities (H‐2.2, 17, 30, 32, and 33) were not detected on C‐1 cells. The C‐1 cells were also unable to absorb the activity of an anti‐la serum (1–28) directed to la.1, 2 and 19 (lak) specificities. Transplantation studies showed that resistance against the challenge of C‐1 cells could be induced in syngeneic BALB/c mice by preimmunization with normal tissues from C3Hf and AKR (H‐2k), A (H‐2a) and C57BL/6J (H‐2b) strains (expressing all or some of the extra H‐2 antigens of the tumor) whereas no protection was obtained with DBA/2 (H‐2d) or with W/Fu rat tissues. The anti‐tumor activity could be passively transferred by BALB/c lymphoid cells immune to normal C3Hf, AKR, A, and NIH (H‐2q) tissues, but no protection was achieved with lymphoid cells immune to DBA/2 or to W/Fu normal rat tissues. These data indicate that foreign H‐2 antigens are expressed on C‐1 tumor and that they might function as tumor‐associated transplantation antigen which was shown to be present and individually distinct on this sarcoma by appropriate in vivo tests.
Tumour‐specific complement‐dependent serum cytotoxicity against a chemically induced rat hep atoma
Authors: Price Michael R. , Baldwin Robert W. 
Published: February 2007

AbstractA short‐term 51Cr release test was used for the detection of complement‐dependent cytolytic activity of syngeneic serum for transplanted aminoazo dye‐induced rat hepatoma cells in suspension. Serum samples from rats bearing intraperitoneal implants of one hepatoma (hepatoma D23) were specifically cytotoxic for hepatoma D23 target cells, although this activity was not detected in sera from donors bearing subcutaneous tumour grafts. Other sera containing demonstrable IgG antibodies reactive in membrane immunofluorescence tests with individually distinct tumour‐specific antigens or tumour‐associated embryonic antigens were not cytotoxic for hepatoma D23 cells; and even though serum from donors carrying intraperitoneal tumour grafts contained tumour‐specific IgG antibody, the complement‐dependent reactivity was confined to the 19s region of fractionated tumour‐bearer serum. These findings are discussed in relation to the development of humoral responses in the tumourbearing host and with regard to the significance of the availability of an objective and reproducible assay for measuring humoral responses directed against the tumour‐specific antigens associated with chemically induced rat tumours.
Spontaneous and induced appearance of murine leukemia virus antigen containing cells in organ cultures of embryonic mouse thymus
Authors: Riesenfeld Inger , Alm Gunnar V. 
Published: February 2007

AbstractThe potential of embryonic thymus organ cultures for studies on relations of endogenous MuLV, lymphoid cells and thymic microenvironment to lymphoma development were evaluated. Four main findings are reported. First, thymuses of 14‐day‐old CBA and AKR embryos could be maintained in organ cultures for at least 9 weeks with sustained production of lymphocytes. Lymphopoiesis in CBA and AKR thymuses were not grossly different. Secondly, an indirect immunofluorescence (IF) technique demonstrated spontaneous appearance of MuLV‐antigen‐containing cells in AKR, but not in CBA thymuses. Such spontaneous MuLV expression first occurred after 16 days of organ culture, thereafter infrequently and at random in individual thymus cultures. Thirdly, incubation of AKR and CBA thymuses in lymphoma extract containing AKR‐type MuLV at initiation of organ cultures induced MuLV‐antigen‐containing cells. These were first detected after 7‐14 days in culture, somewhat earlier and initially more frequently in AKR than in CBA thymuses. In the former, induction was accompanied by a clear reduction in the number of lymphocytes per thymus. Fourthly, iododeoxyuridine (IdUrd) treatment of AKR thymuses on culture day 0, 3 or 7 decreased the number of lymphocytes per thymus and induced appearance of MuLV‐antigen containing cells, assayed 8‐20 days later. The IdUrd effect was most marked on day 0, and decreased successively on days 3 and 7. IdUrd had a much slighter effect on CBA thymuses, causing a lower reduction in cell numbers and inducing few MuLV‐antigen cells. These main results clearly demonstrate the potential usefulness of the organ culture system for studies on leukemogenesis. It may be directly applied to answer several questions raised by detailed findings in our study.
Asbestos and lung cancer: An analysis of the epidemiological evidence on the asbestos—smoking interaction
Authors: Saracci R. 
Published: February 2007

AbstractThree simple models for the asbestos—smoking interaction on human lung cancer production are considered. In the first model the excess incidence of lung cancer independently due to asbestos and to smoking adds together when both agents are present (additive model). In the second the addition of each one of the two agents produces an effect (increase in lung cancer incidence) which is proportional to the effect of the other (multiplicative model). In the third, asbestos can only increase lung cancer incidence in the presence of smoking. As previously found by other investigators, the additive model appears the least plausible in the light of the data from two published epidemiological studies. A discrimination between the other two models is attempted through a detailed analysis of the five published epidemiological studies today available which provide information on occupational asbestos exposure, smoking habits and lung cancer risk. Although the data do not allow a definitive discrimination, the multiplicative model appears to be more plausible, being also consistent with a multistage carcinogenic mechanism and with evidence from animal (rat) experiments. It is relevant both for biology and for public health that in this model asbestos and smoking are regarded as independently capable of producing lung cancer in humans and that they act synergistically when exposure to both occurs.
Increased ferritin synthesis and release by hodgkin's disease peripheral blood lymphocytes1
Authors: Sarcione Edward J. , Smalley James R. , Lema Mark J. , Stutzman Leon 
Published: February 2007

AbstractPeripheral blood lymphocytes from patients with all stages of untreated Hodgkin's disease and from normal healthy adults were shown to synthesize and release ferritin in vitro. Ferritin synthesis was confirmed by immunoelectrophoresis, double immunodiffusion and autoradiography. Hodgkin's disease lymphocytes synthesized ferritin 4.2 times faster and released it 2.4 times faster than did normal lymphocytes, whereas total protein synthesis was faster in normal lymphocytes. Patients with nodular sclerosis and perhaps those with absence of fever had the highest synthetic rates; however no relationship was observed between relative rates of lymphocyte ferritin synthesis and sex, age, anatomical stage and presence of splenic or hepatic involvement by tumor. Addition of iron to normal human lymphocytes produced little or no change in ferritin synthesis. These data indicate that part of the intracellular ferritin detected in peripheral blood lymphocytes from patients with Hodgkin's disease and from normal individuals resulted from de novo synthesis rather than from uptake and storage of serum ferritin, and suggests that elevated ferritin levels detected in the serum and tumor tissue of Hodgkin's disease patients originate from lymphocytes.
Membrane receptor stripping confirms the association between ebv receptors and complement receptors on the surface of human b lymphoma lines
Authors: Yefenof Eitan , Klein George 
Published: February 2007

AbstractComplement (C3) receptors, EBV receptors, Fc receptors, membrane IgM and beta2microglobulin (β2m) were individually stripped from the surface of human B lymphoma lines. The cells were subsequently tested for their ability to absorb infectious EB virus. Stripping of Fc receptors, IgM and β2m did not reduce EBV absorption. Stripping of either EBV receptors or C3 receptors eliminated or drastically reduced EBV‐absorptive capacity. The results confirm the distinctive association between EBV receptors and C3 receptors on human lymphoma cells.
Detection of herpes simplex virus‐related antigens in the nuclei and cytoplasm of biochemically transformed cells with peroxidase/anti‐peroxidase immunological staining and indirect immunofluorescence
Authors: Kurchak Mark , Dubbs Del Rose , Kit Saul 
Published: February 2007

AbstractHerpes simplex virus (HSV)‐related antigens have been demonstrated in the nuclei and cytoplasm of human and mouse cells biochemically transformed by ultraviolet light‐irradiated HSV. This was accomplished by using peroxidase/anti‐peroxidase immunological staining and indirect immunofluorescence with rabbit antisera that had high neutralizing titers against the HSV‐specific thymidine kinase activity and virus infectivity. HSV‐1 antisera reacted with antigens in cells biochemically transformed by type 1 HSV, but not with those of cells biochemically transformed by type 2 HSV. Similarly, HSV‐2 antisera reacted with antigens in cells biochemically transformed by HSV‐2, but not with those in cells biochemically transformed by HSV‐1. In contrast, herpes virus‐related antigens were detected in cells cytolytically infected with HSV‐1 and with HSV‐2 by either type 1 or type 2 HSV antisera. These observations suggest that the antigens detected in the biochemically transformed cells were a type‐specific subset of the HSV‐related antigens synthesized in cells undergoing productive infection by HSV‐1 and HSV‐2.
Natural cell‐mediated cytotoxicity in mice against non‐lymphoid tumor cells and some normal cells
Authors: Nunn M. E. , Herberman R. B. , Holden H. T. 
Published: February 2007

AbstractLymphocytes from normal mice were found to have cell‐mediated cytotoxicity, in a short‐term 51Cr release assay, against a variety of non‐lymphoid tumor cells as well as against lymphomas. Some of the non‐lymphoid tumors were as susceptible to natural cytotoxicity as the standardly used lymphoid lines. Some tissue culture cell lines and in vivo passaged tumor lines were susceptible to lysis, as were some primary virus‐induced lymphomas. Tumors which arose in nude mice, which have high levels of natural cytotoxic activity, were all resistant to lysis. In addition to the susceptibility of transformed cells to natural cell‐mediated cytotoxicity, some untransformed cultured cells and cells from normal tissues were targets for this mechanism. Low levels of cytotoxicity were seen with normal thymus cells, bone‐marrow cells, and short term cultures of macrophages, whereas normal spleen and lymph‐node cells were completely resistant to lysis. These results indicate a broader spectrum for mouse natural cell‐mediated cytotoxicity reactivity than has been previously recognized.
Soluble tumor antigen‐induced lymphocyte proliferation: Effects of serum from normal and tumor‐bearing mice
Authors: Calderwood Maron B. , Forbes James T. , Smith Richard T. 
Published: February 2007

AbstractThe effect of serum from mice bearing methylcholanthrene‐induced fibrosarcomas on the lymphoproliferative responses of their spleen and lymphnode cells to 3 M KCI‐solubilized tumor antigens has been investigated. Low concentrations of serum (≤2.5%) collected throughout the course of tumor growth were inhibitory. Normal sera collected from age‐matched control mice were often slightly inhibitory, but to a significantly lesser extent at identical serum concentrations. The inhibitory effect of tumor‐bearing serum was not limited to homologous tumors, but was also observed when cross‐reacting syngeneic tumor antigens or serum from animals bearing other syngeneic tumors were added to the assay mixture. At the low concentrations used, tumor‐bearing sera inhibited only tumor‐antigen‐induced proliferation, and not proliferation induced by T cell mitogens. The inhibitory effects of tumor‐bearing sera on lympho‐proliferative responses to soluble tumor antigens appear to be similar to the inhibition seen as “serum blocking” in other assays of tumor immunity.
An analysis of the g‐banded chromosomes of the golden hamster
Authors: Pavia R. A. , Smith L. W. , Goldenberg D. M. 
Published: February 2007

AbstractChromosomes from 20 G‐banded karyotypes of golden hamster cheek pouch cells were precisely measured to determine total lengths and arm ratios. Mean values were used t o establish an idiogram which may serve as the basis for a standard hamster karyotype.
Relationship between the Epstein‐Barr virus and undifferentiated nasopharyngeal carcinoma: Correlated nucleic acid hybridization and histopathological examination
Authors: Andersson‐Anvret Maria , Forsby Nils , Klein George , Henle Werner 
Published: February 2007

AbstractIn order to examine critically the closeness of association between Epstein‐Barr virus (EBV) DNA and nasopharyngeal carcinoma (NPC) a correlated histopathological and nucleic acid hybridization study was performed on 51 undifferentiated NPC, 4 NPC with some signs of squamous differentiation, 7 nasopharyngeal tumors of other histological types and 14 head and neck carcinomas located outside the nasopharynx. All 51 undifferentiated NPCs contained significant numbers of EBV‐genome copies per cell. Two of the somewhat differentiated NPCs were also EBV‐DNA‐positive, whereas 2 were negative. Of the 7 other nasopharyngeal tumors, 1 was EBV‐DNA‐positive. Histological examination, however, showed that this was a typical Burkitt lymphoma. The other 6 tumors were all EBV‐DNA‐negative lymphoproliferative malignancies. All 14 head and neck carcinomas located outside the nasopharynx were EBV‐DNA‐negative. The sera of undifferentiated NPC patients had elevated antibody titers against the EBV‐determined antigens, the EA (D) component in particular. These findings confirm that there is a regular association between EBV‐DNA and undifferentiated NPC.
Detection of epstein‐barr virus antigens with enzyme‐conjugated antibody
Authors: Granlund David J. , Andrese Angelo P. 
Published: February 2007

AbstractMonospecific conjugated (fluorescein isothiocynate and horseradish peroxidase) goat antisera, prepared against three human immunoglobulin classes, IgM (μ), IgG (γ) and IgA (α), were compared for their ability to detect human Ig classes possessing specificity for Epstein‐Barr virus (EBV) viral capsid antigens (VCA) in a chronically infected human lymphoid cell line, P3J‐HRIK. It was determined that the enzyme system was significantly more sensitive than immunofluorescence in detecting most of the immunoglobulins in sera from cancer patients. Some patients with nasopharyngeal carcinomas (NPC) had extremely high levels of EBV‐specific IgA, whereas cancers other than NPC may have lower EBV‐specific IgA titers.