bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disease‐related lymphocyte cytotoxicity in rats bearing transitional cell carcinoma of bladder. effect of immunomodulators
Authors: Moroz Chaya , Madgar Igael , Twig Shoshana , Lindner Arie , Many Moshe 
Published: February 2007

AbstractBlood lymphocytes from rats bearing transitional cell carcinoma (TCC) of the bladder were studied for their cytotoxicity in vitro against xenogeneic YAC‐1 target and against syngeneic TCC cells. Control lymphocytes were obtained from age and sex‐matched syngeneic rats. The following differences were observed: (I) lymphocytes from TCC‐bearing rats were cytotoxic to syngeneic TCC target cells whereas those from control rats were not; (2) lymphocytes from TCC‐bearing and control rats were cytotoxic to NK sensitive YAC‐I cells; however, NK cells from TCC‐bearing rats were more adherent to nylon wool‐columns than NK cells from control rats. The adherent and non‐adherent cells from TCC‐bearing rats were both cytotoxic to syngeneic TCC target cells. Levamisole treatment of effector cells from TCC‐bearing rats did not affect the NK activity, yet it increased the cytotoxicity of non‐adherent cells on TCC target cells. Treatment of the adherent cells with poly‐l:poly‐C increased slightly their NK activity on YAC‐I cells and their anti‐TCC cytotoxicity. However, a marked increase in the cytotoxicity by both adherent and non‐adherent cell fractions was observed on TCC target cells pretreated with poly‐l:poly‐C. A disease‐related cytotoxicity of lymphocytes from rats bearing TCC has been observed. Treatment of TCC target cells with poly‐l:poly‐C increased their susceptibility to lysis by the activated effector cells.
Suppressor macrophages in tumor‐bearing mice. Inconsistency between in vivo and in vitro findings?
Authors: Forni Guido , Giovarelli Mirella , Lanfrancone Luisa , Varesio Luigi 
Published: February 2007

AbstractThe growth of a spontaneous adenocarcinoma (ADK‐It) of BALB/c mice (H‐2d, Mlsb) induces progressive hyporesponsiveness of spleen cells stimulated with PHA or irradiated leukocytes from DBA/2 strain (H‐2d, Mlsa) in mixed leukocyte culture. This hyporesponsiveness is due to the suppressor activity of macrophage‐like cells, since it is abrogated by passage over nylon‐wool columns, pretreatment with carrageenans, or carbonyl iron and magnet. BALB/c mice bearing >20 mm mean diameter ADK‐It tumors, and displaying a drastic impairment of T lymphocyte reactivity in vitro, were challenged with the P815 mastocytoma of the DBA/2 strain. These mice rejected increasing numbers of P815 cells to the same extent as normal BALB/c mice. The reactivity towards P815 is abrogated by 450 rad, and can be reconstituted by the adoptive transfer of 2 × 107 normal T lymphocytes in either normal or ADK‐It bearing BALB/c mice. These data show that a discrepancy exists between the capacity of T lymphocytes from ADK‐It bearing mice to react against DBA/2 cells tested in vitro or in vivo, and indicates that great caution should be exercised in predicting the responsiveness of the immune system on the basis of in vitro data on the suppressor activity of macrophages.
Growth control and cell spreading: Differential response in preneoplastic and in metastatic cell variants
Authors: Raz Avraham , Ben‐Ze'ev Avri 
Published: February 2007

AbstractGrowth control and sensitivity to changes in cell shape were studied in anchorage‐dependent mouse fibroblasts (diploid fibroblasts, 3T3 and 3T6), in DNA tumor‐virustransformed mouse fibroblasts (SVPy 3T3), in four B16 melanoma and five uv‐2237 fibrosarcoma cell variants that exhibit distinct metastatic properties. Differential adhesive conditions were established by precoating the plastic plates with poly (2‐hydroxyethylmethacrylate) that allowed an accurate and reproducible control of cell shape, from flat to spherical. Mouse fibroblasts that form a continuum between rigorously controlled cells to fully anchorage‐independent cells, display a direct correlation between degree of growth control and sensitivity to changes in cell spreading. In contrast, there is no apparent direct correlation between sensitivity of growth control to changes in cellular configuration and the metastatic potential of tumor cells.
Interaction of Epstein‐Barr virus with leukaemic B cells in vitro. II. Cell line establishment from prolymphocytic leukaemia and from Waldenström's macroglobulinaemia
Authors: Finerty S. , Rickinson A. B. , Epstein M. A. , Platts‐Mills T. A. E. 
Published: February 2007

AbstractLeukaemic B‐cell populations were prepared from six patients with high‐count prolymphocytic leukaemia (PLL) as well as from one patient with Waldenström's macroglobulinaemia (WM) in frankly leukaemic phase, and their response to in vitro Epstein‐Barr (EB) virus infection was monitored in terms of expression of the virus‐associated nuclear antigen EBNA and of virus‐induced transformation to continuous cell lines. The individual leukaemic populations, tested on several occasions, gave reproducibly different responses one from another which were not obviously related to differences either of surface immunoglobulin phenotype or of immunoglobulin secretor status in vivo. After infection, four out of six PLL populations showed either transient or a more persistent expression of EBNA, always involving a minority of the cells, with no evidence of any virus‐induced transformation up to six weeks. In contrast, two out of six PLL samples as well as the WM sample rapidly gave rise to EBNA‐positive cell lines which, on the evidence both of restricted immunoglobulin class expression and of abnormal marker chromosomes, were clearly derived from the leukaemic cells. Further comparative studies of such leukaemic B‐cell populations may help to define host cell components necessary for the triggering of EB‐virus‐induced cellular transformation.
Expression on cultured human tumour cells of placental trophoblast membrane antigens and placental alkaline phosphatase defined by monoclonal antibodies
Authors: McLaughlin P. J. , Cheng M. H. , Slade M. B. , Johnson P. M. 
Published: February 2007

AbstractThe cellular reactivity of six monoclonal antibodies (McAbs) produced to isolated human placental syncytiotrophoblast microvillous plasma membranes has been examined using a variety of normal and malignant cell types. Two McAbs reacted with antigenic determinants common to most normal human cells. Two other McAbs (H310 and H316) reacted predominantly with normal placental trophoblast and with lymphocytic cells, as well as with most transformed or neoplastic cultured cell lines. Two further McAbs (H315 and H317) identified foetal differentiation antigens expressed only on the membranes of normal placental trophoblast and of certain tumor cell lines. H317 has been shown to be specific for the heatstable L‐phenylalanine‐inhibitable placental‐type alkaline phosphatase isoenzyme. These latter McAbs (H315 and H317) may prove useful in monitoring of some human cancers.
Chromosomes of human hepatoma cell lines
Authors: Simon Daniela , Aden David P. , Knowles Barbara B. 
Published: February 2007

AbstractThe karyotypes of three human hepatoma cell lines Hep G2, Hep 3B and PLC/PRF/5 were investigated by G‐ and C‐banding techniques. In addition to ploidy changes, typical for most carcinoma cell lines, certain markers were found that remained stable throughout passage of these cultures. Chromosome I is involved in multiple translocations, resulting in at least three copies of the chromosome I heterochromatin region in each cell line. Inversion in the 9qh region is also seen. In addition, each of the cell lines consistently contains trisomy of 17q. The rearrangements of chromosome I are most striking in the Hep 3B and PLC/PRF/5 cell lines, which are derived from human hepatocellular carcinomas and contain integrated copies of the hepatitis B viral genome. These two cell lines are characterized by the presence of at least five copies of the I (p13←q21) region that result from multiple deletions and/or translocations; by consistent trisomy and polymorphism of the 9qh region; and by trisomy of chromosome 10 (also involved in rearrangements). The Hep G2 and Hep 38 cell lines behave functionally as highly differentiated liver parenchymal cells and are karyologically distinguishable from PLC/PRF/5 both by the presence of trisomy of 6 (pter←q14) and by the finding that one of the homologues of chromosome 15 is 15q+.
Immunochemical demonstration of an ovarian cancer‐associated urinary peptide
Authors: Stenman Ulf‐Håkan , Huhtala Marja‐Liisa , Koistinen Riitta , Seppälä Markku 
Published: February 2007

AbstractImmunization with a peptide fraction from ovarian cancer urine resulted in an antiserum that reacts with a 6,000‐dalton (6K) peptide. In urine from some patients with advanced gynaecological cancer, the concentration of 6K peptide was high enough to be detected by immunodiffusion. By radioimmunoassay the levels in normal serum could be determined. The concentration in serum was 5–20 μg/1 and that in urine 5–50 μg/1. Elevated levels were observed in urine from 5 out of 8 patients with ovarian cancer, 10 out of 14 patients with cervical cancer and 9 out of 14 patients with endometrial cancer. The highest level observed was 12,000 μg/1. High concentrations of the 6K peptide (100–300 μg/1) were observed in amniotic fluid from 14–16 weeks of pregnancy. Some tumor extracts also had a high concentration of the 6K peptide. No immunological relationship was observed between the peptide and known tumor‐associated antigens or serum proteins. These results suggest that the peptide is a new oncodevelopmental peptide which may have significance as a tumor marker.
Direct cytolysis by partially‐purified preparations of immune interferon
Authors: Tyring Stephen , Klimpel Gary R. , Fleischmann W. Robert , Baron Samuel 
Published: February 2007

AbstractMouse IFNγ preparations purified 30‐fold were found to have direct cytolytic activity against a number of tumor and normal cells. Cell killing was determined using a sensitive, rapid and accurate assay which employed very low numbers of cells and very small quantities of interferon. The cytolytic activity of IFNγ on 11 murine tumor cell lines was investigated. A 20‐fold difference was found between the most sensitive cell type, P‐388 lymphoma, versus the most resistant cell type, C127v leukemia. A number of normal mouse cells was also found to have low to intermediate sensitivity to the cytolytic action of IFNγ. Human IFNγ was also shown to have cytolytic activity which, like mouse IFNγ, was relatively species‐specific. Direct cytolysis was not found to be a characteristic of IFN‐α/β. Different mechanisms of action for the antiviral and cytolytic activities of IFNγ are indicated because the cytolytic titer of IFNγ did not parallel its antiviral titer on most cell types and increasing the cell number produced a decrease in the cytolytic titer and an increase in the antiviral titer. High concentrations of IFNγ (i.e., 2,900 units/ml) resulted in complete lysis of cells within 24 h, while lower concentrations (i.e., 700 units/ml) resulted in a reversible inhibition of cell growth during this time period. Evidence that the cytolytic substance in the IFNγ preparation was IFNγ include the following: (1) both antiviral and anticellular activities copurified through a 30‐fold purification; and both activities were (2) relatively speciesspecific; (3) sensitive to heat; (4) inactivated by low pH and (5) neutralized by antibodies to IFNγ. Therefore, we propose the possibility that direct cytolysis is yet another of IFNγ's distinctive antivities.
Identification of the RPMI 8226 retrovirus and its dissemination as a significant contaminant of some widely used human and marmoset cell lines
Authors: Popovič M. , Kalyanaraman V. S. , Reitz M. S. , Sarngadharan M. G. 
Published: February 2007

AbstractA retrovirus designated RPMI 8226V, isolated in 1973 from the human myeloma cell line RPMI 8226 has been characterized by competition radioimmunoassay (RIA) for the major viral structural protein and by nucleic acid hybridization analysis using cDNA of the virus. The virus is highly related to the squirrel monkey type D retrovirus, SMRV. In the homologous RIA using rabbit anti‐RPMI 8226V and 125I‐labelled p36 of RPMI 8226V, RPMI 8226V and SMRV exhibited competition of 81% and 73% respectively. Similarly, in the homologous system for SMRV p36, these viruses competed 98 and 100%. Reagents made from the type D retrovirus, Mason Pfizer Monkey Virus (MPMV), known to be related but distinct from SMRV, were used in assays designed to detect interspecies determinants of type D retroviruses. In assays using goat anti‐MPMVp26 vs SMRV 125I‐p36, RPMI 8226V, SMRV and MPMV competed to the same extent (93%). Hybridization analysis of RPMI 8226V cDNA showed significant homology to cellular RNA and DNA of mink, bat, and human cells infected with RPMI 8226V and to DNA of SMRV infected cells but not to uninfected cells or cells infected with other viruses. These results taken together clearly indicate that RPMI 8226V and SMRV are very closely related to each other. The finding of a type D retrovirus in this human myeloma cell line that had been used in EBV studies (the usual source of EBV being the marmoset cell line B95‐8) prompted a survey of RPMI 8226V in some human and marmoset cell lines. The assays included the RIA for p36, nucleic acid hybridization using cDNA of RPMI 8226V, reverse transcriptase analysis, and electronmicroscopy (EM). The results clearly show that in addition to RPMI 8226, human Burkitt lymphoma cells BJAB/B‐95‐8/K which were supertransformed by EBV from B‐95‐8/K marmoset cells as well as marmoset cell lines [(B‐95‐8/K and B‐95‐8/N) obtained from Stockholm and Uppsala, Sweden] were positive for the RPMI 8226V. Similar lines obtained elsewhere were negative. The results obtained clearly indicate that RPMI 8226V is a serious laboratory contamination in some widely used human cell lines. The possible impact of this viral contamination for some virological and cell biological studies is discussed.
Mammary tumor induction in inbred mouse strains with urethane is not accompanied by changes in expression of B‐ and C‐type retroviral structural proteins
Authors: Imai Shunsuke , Morimoto Junji , Tsubura Yoshihiko , Hilgers Jo 
Published: February 2007

AbstractUrethane administrated in the drinking water of breeding female mice of five inbred strains (DDf, KF, C3Hf, ddY and C57BL) leads to a higher incidence of mammary tumors at an extremely early age in four of these strains (DDf, KF, C3Hf and ddY). In the case of the DDf strain the tumors are adenoacanthomas, but in the case of the other strains adenocarcinomas are also observed. The effect of urethane in the drinking water on expression of endogenous retroviral structural proteins of the B and C type (MTV and MuLV) was studied in the milk by an immunodiffusion test and in organ extracts by radioimmunoassays (for MTVp27, MTVgp52 and MuLVp30). Organs tested include salivary glands, thymus and spleen from female and male animals. In addition, prostate and seminal vesicles were tested in male animals and uterus and mammary glands in females. Mammary tumors induced by urethane were also tested. Urethane does not induce or enhance endogenous retroviral antigen expression, either in these organs or in the mammary gland, one of the target organs for tumorigenesis by this agent.
Vitamin A levels in human bladder cancer
Authors: Mahmoud Lotfy Abdel Naby , Robinson William A. 
Published: February 2007

AbstractThe following studies were undertaken to determine the levels of serum carotene and vitamin A (retinol) in Egyptian patients with intestinal, urinary, hepatosplenic schistosomiasis, and bladder cancer. These studies have shown that both serum carotene and serum retinol levels are significantly reduced in patients with bladder cancer when compared to controls. These data, when viewed in light of previous animal studies noted, raise the question as to whether vitamin A administration can be beneficial in the prevention and/or treatment of human bladder cancer, particularly that associated with schistosomiasis.
Neoplastic transformation of human cells in culture associated with deficient repair of light‐induced chromosomal DNA damage
Authors: Parshad Ram , Sanford Katherine K. , Jones Gary M. , Tarone Robert E. 
Published: February 2007

AbstractTwo lines of normal human skin fibroblasts and five derivative lines transformed in culture to neoplastic cells by chemical carcinogens were compared with respect to chromatid breakage produced by exposure to low‐intensity fluorescent light (cool‐white, 4.6 W/m2) during pre‐S, S, and late S‐G2 periods of the cell cycle. Five additional normal human cell lines and a line derived from a lung adenocarcinoma were also examined for chromatid damage following light exposure during pre‐S and late S‐G2. On the assumption that each chromatid (half chromosome) contains a single continuous DNA double helix, chromatid breaks seen in the first post‐treatment metaphase must represent unrepaired DNA doublestrand breaks. The frequency of chromatid breaks induced by pre‐S light exposure in the neoplastic cell is not significantly different from that in the normal cells. However, addition of caffeine, an inhibitor of DNA repair, to the culture medium following light exposure significantly increases the frequency of chromatid breaks in the neoplastic but not in the normal cells. One possible explanation for these observations is that the normal cells, known to have effective excision repair, remove the DNA damage, whereas the neoplastic cells, presumably deficient in excision repair, handle the damage during S by a caffeinesensitive mechanism. Furthermore, the neoplastic but not the normal cells, show significant increases in chromatid breaks when exposed during S or late S‐G2The chromatid damage produced by late S‐G2 exposure can be completely prevented by addition of mannitol, a scavenger of free hydroxyl radicals. Addition of caffeine to the culture medium during late S‐G2 light exposure has no effect on the frequency of chromatid breaks in the neoplastic cells but signincantly increases chromatid breakage in the normal cells. These results suggest that the normal cells repair the late S‐G2 light‐induced damage by a caffeine‐sensitive repair mechanism that is absent or deficient in the neoplastic cells. It thus appears that neoplastic cells are deficient in mechanisms for repair of DNA damage induced by light both during pre‐S and late S‐G2periods of the cell cycle.
Interferon and natural killer activity in multiple myeloma. Lack of correlation between interferon‐induced enhancement of natural killer activity and clinical response to human interferon‐α
Authors: Einhorn Stefan , Ahre Anders , Blomgren Henric , Johansson Bo , Mellstedt Håkan , Strander Hans 
Published: February 2007

AbstractNatural killer (NK) activity of peripheral lymphocytes was measured in 39 patients with multiple myeloma prior to and during interferon (IFN) therapy. NK activity increased in a majority of patients following the first injection of IFN and remained at an increased level during I year of therapy. Lower doses of IFN seemed to induce a greater increase in NK activity than higher doses. No correlations could be observed between the response of the tumors to IFN therapy and pretreatment levels of NK activity, IFN‐induced enhancement of NK activity in vitro or IFN‐induced enhancement of NK activity in vivo.
Acquisition of tolerance to the antiproliferative activity of interferon by X‐ray transformed C3H/10T1/2 cells under prolonged treatment with interferon
Authors: Brouty‐Boyé Danièle 
Published: February 2007

AbstractX‐ray‐transformed C3H/10T1/2 cells serially passaged in the presence of highly purified mouse interferon appeared to acquire progressively a tolerance to the inhibitory effect of interferon on cell proliferation. In contrast, these cells did not appear to develop a tolerance to the antiviral activity of interferon. These results suggest the possibility that these two effects of interferon are mediated by different mechanisms.
Translocation t(8;22) in peripheral lymphocytes and established lymphoid cell lines from a patient with Hodgkin's disease followed by acute lymphatic leukemia
Authors: Fonatsch Christa , Burrichter Heinz , Schaadt Michael , Kirchner Hartmut H. , Diehl Volker 
Published: February 2007

AbstractCytogenetic studies on primary material and established cell lines of a patient with B‐cell non‐Hodgkin Lymphoma with leukemic presentation as secondary malignancy after Hodgkin's disease clearly revealed correspondent marker chromosomes in both culture systems. A translocation t(8;22) which has been described in some cases of non‐endemic Burkitt's lymphoma as a variant of the translocation t(8;14) was found in all metaphases of the cell lines and in most of the cells of the primary material. In addition, structural aberrations involving chromosomes 1, 2, 3 and 11, as well as numerical deviations concerning chromosomes 2, 4, 7 and Y, could be observed. The cytogenetical findings are discussed in relation to clinical, immunological and cytochemical data.
Variation in selectivity of tumor cell cytolysis by murine macrophages, macrophage‐like cell lines and NK cells
Authors: Wiltrout Robert H. , Brunda Michael J. , Holden Howard T. 
Published: February 2007

AbstractSeveral murine tumor‐cell lines were tested by isotope release assays for their susceptibility to lysis by either activated peritoneal macrophages (apMPh), macrophage‐like (MPh‐like) cell lines, or natural killer (NK) cells. The qualitative selectivity of tumor‐cell lysis by these different effector cells was quite disparate. The rank order of target cell susceptibility to lysis by apMPh in 24 h assay was L5178Y > P815 ≌ RL♂ > YAC‐1 ≌ MBL‐2. This was seen regardless of whether peritoneal MPh (pMPh) were activated by LPS or poly I:C. Two MPh‐like cell lines, PU‐5R and FC‐1, had a pattern of cytotoxic activity against these target cells that closely paralleled that associated with apMPh, although levels of reactivity differed quantitatively among the effector cells. In contrast, the MPh‐like cell line RAW‐264 expressed a qualitatively different pattern of target‐cell selectivity, preferentially lysing MBL‐2, which was relatively refractory to lysis by other MPh‐like cell likes or apMPh in the 24 h cytolytic assay. When spontaneous or interferon (IFN)‐augmented NK activity was measured against the same panel of target cells, the pattern of selectivity was qualitatively different from that observed for apMPh. The consistent rank order of susceptibility to lysis by NK cells was YAC‐1 > RL♂1 > P815 ≌ L5178Y ≌ MBL‐2. The characteristic patterns of target‐cell selectivity for apMPh or NK cells were the same for all of the strains of mice tested. From the different selectivity patterns of apMPh and NK cells, it is concluded that lysis of target cells is not based solely on inherent sensitivity to cytolysis. Instead, selectivity of lysis is probably due to variations in expression of target‐cell structure recognized by each type of effector cell, and/or in susceptibility to the lytic mechanism(s) of the various effector populations.
High‐ and low‐leukemogenic variants of the radiation leukemia virus (RadLV) differ in ability to induce tumor‐specific immune suppression
Authors: Yefenof Eitan , Zilcha David 
Published: February 2007

AbstractAdult C57BL/6 mice inoculated intrathymically (i.t.) with the highly leukemogenic variant of the radiation leukemia virus (A‐RadLV) develop suppressor cells capable of specifically abrogating a potential anti‐tumor cytotoxic response in vitro. Suppressor cells were generated directly by the virus, independently of an initiation of a leukemogenic process. Inoculation of C57BL/6 animals with the low leukemogenic D‐RadLV variant did not result in suppressor cell generation. It is proposed that induction of tumor‐specific immune suppression by A‐RadLV is essential for tumor progression, and the leukemogenic activity of D‐RadLV is attributed to its inability to recruit suppressor cells.