bluuebunny/crossref_metadata_2025 huggingface dataset:
Absorption of blocking activity from human tumor‐bearer sera by staphylococcus aureus, cowan I
Authors: Steele G. , Ankerst J. , Sjögren H. O. , Vang J. , Lannerstad O.
Published: February 2007

Staphylococcus aureus, strain Cowan I, contains a cell‐wall substance, protein A, which combines with the Fc part of IgG in most mammalian species. It can therefore be used as a solid‐phase immunoabsorbant for elimination of the reacting immunoglobulins. Since it has been shown that Cowan I could absorb out the blocking activity of sera from rats bearing isografts of polyoma‐virus‐induced sarcomas or chemically induced colon carcinomas, we investigated what effects Cowan I absorption of human tumor‐bearer sera might have. In all tumor‐bearer sera tested, from patients with melanomas or colon carcinomas, treatment with protein‐A‐containing staphylococci decreased the sera's ability to inhibit lymphocyte‐mediated cytotoxicity in vitro. Cowan‐I‐treated sera from healthy controls had no effect on lymphocyte cytotoxicity. Nor did Cowan‐I‐treated tumor‐bearer sera potentiate or „arm”︁ normal lymphocytes against tumor target cells. There was no evidence of complement‐dependent cytotoxicity with added human complement in sera from melanoma and colon carcinoma bearing patients either before or after absorption with Staphylococcus aureus, Cowan I. The concentrations of IgA, IgG and IgM were determined in sera used for in vitro tests of blocking activity and complement‐dependent cytotoxicity before and after absorption. No reduction of IgA, reduction to undetectable levels of IgG and 20–30% reduction of IgM immunoglobulins as compared to unabsorbed sera were demonstrated.
Characteristics of cell lines derived from human leukocytes transformed by different strains of epstein‐barr virus
Authors: Katsuki Takato , Hinuma Yorio
Published: February 2007

Variation of Epstein‐Barr virus (EBV) in respect to its effect on the properties of transformed cells was probed. Human umbilical cord leukocytes from six different individuals were transformed in vitro by either B95‐8 (B) or QIMR‐WIL (Q) strains of EBV and subsequently 12 lymphoblastoid cell lines (six B‐derived and six Q‐derived lines) were established. The B lines and Q lines were different in the expression of EBV genome i.e. production of virus or viral antigens, and in other properties including growth pattern and immunoglobulin production. The most striking differences between the two groups lay in their capacity to produce infectious virus and in the shape of the cell‐clumps. The results suggest that different strains of EBV may induce transformed cells with different characteristics.
Isolation of type‐c viruses from the asian feral mouse mus musculus molossinus
Authors: Lieber Michael , Sherr Charles , Potter Michael , Todaro George
Published: February 2007

N‐tropic and xenotropic type‐C viruses have been isolated from the wild Asian mouse subspecies M. musculus molossinus. By host range, morphologic and some immunologic criteria these viruses appear closely related to the previously studied murine type‐C viruses isolated from highly inbred laboratory strains of mice.
Immunological mechanisms in the pathogenesis of virus‐induced murine leukemia. I. Autoreactivity
Authors: Proffitt Max R. , Hirsch Martin S. , Gheridian Beatriz , McKenzie Ian F. C. , Black Paul H.
Published: February 2007

By an in vitro microcytotoxicity assay, thymocytes from mice infected with Moloney murine leukemia virus since birth (MuLV‐M carriers) caused a dramatic reduction of normal, non‐infected syngeneic target cells; they usually spared identically derived target cells infected with MuLV‐M. Thymocytes from normal mice slightly stimulated the replication of the same target cells. This pattern of carrier thymocyte reactivity was evident at all ages tested during both preneoplastic and neoplastic periods. Transplantable lymphoma cells derived from a carrier mouse with overt thymic lymphoma behaved similarly. Lymphocytes from the spleens and lymph nodes of young preleukemic carriers (8–12 weeks old) usually were reactive against MuLV‐M‐infected target cells and not against non‐infected target cells. In contrast, lymphocytes from older preleukemic carriers (16–17 weeks old) reacted in a manner similar to carrier thymocytes. These observations suggest that the thymic lymphoma induced by MuLV‐M may result in part from an autoreactive process originating in the thymus, but eventually spreading to the peripheral lymphoid tissues.
The antigenicity of carcinoembryonic antigen in man
Authors: Macsween J. M.
Published: February 2007

Binding of globulins to 125I CEA was detected in 10 of 24 sera from patients with cancer, 13 of 26 sera from blood donors, and 7 of 27 supernates of tumor‐cell suspensions. Binding was predominantly by IgM in 10 of 14 sera tested by radioimmunoelectrophoresis. Binding was inhibited by 6 ng unlabelled CEA in one instance only, and by adsorption with blood group A erythrocytes in three cases. Binding was not increased in dialysed precipitates formed by ammonium sulfate at pH 2.5, while there was increased binding in precipitates of complexes of CEA and heterologous anti‐CEA. These results confirm that human IgM binds to CEA, and in some cases binding appears to be mediated by antibodies to blood group A. However, the binding is weak and appears to be of low affinity. This suggests that binding of CEA by immunoglobulins represents cross‐reactivity by antibodies to similar antigens, of which blood group A is one example.
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

The 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

Spontaneous 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

N‐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

In 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

Specimens 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

The 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

We 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

The 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

Five‐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

The 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

A 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

Sera 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

The 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

Evidence 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

The 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

Untransformed, 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

A 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.
Subpopulations of multiparous rat lymph‐node cells cytotoxic for rat tumour cells and capable of suppressing cytotoxicity in vitro
Authors: Rees R. C. , Bray Judith , Robins R. A. , Baldwin R. W.
Published: February 2007

Lymph‐node cells (LNC) from multiparous pregnant rats were separated on columns prepared from nylon wool, and tested for cytotoxicity against target tumour cells. Reactivity of LNC towards hepatoma D23 and mammary carcinoma AAF57 was demonstrated in cell populations retained on the nylon wool, and not with cells eluted from the column. Although only 25% of the samples of unfractionated LNC were cytotoxic for tumour cells, retained cell fractions were cytotoxic in 11 out of 12 tests (p = <0.05). Similarly retained LNC were also cytotoxic for 15‐day‐old embryo cells but not for normal adult rat fibroblasts. Using multiparous rat serum it was shown that the reactivity of the retained LNC population could be abrogated in eight out of 11 tests (p = <0.05). The LNC population recovered from the nylon wool constituted 28 to 35% of the original LNC preparation, and consisted of 60–70% Ig‐bearing cells together with a subpopulation of cells responding to soluble PHA. Separation of multiparous LNC on glass beads coated with rat Ig and then rabbit anti‐rat Ig (in excess) also demonstrated the retained cell population to be cytotoxic against tumour cells. Approximately 17–20% of the original cell population was recovered from cells retained on the column, and consisted of an enriched Ig‐bearing cell population (65–80% Ig‐bearing cells) and LNC responsive to PHA. Carbonyl iron treatment of multiparous rat LNC was found to remove detectable cytotoxicity from multiparous rat LNC preparations. The cytotoxicity of multiparous rat LNC retained on nylon wool was also abolished following incubation with carbonyl iron. Definite conclusions as to the nature of the effector cell cannot be drawn from this test, since carbonyl iron treatment was found to remove not only phagocytic cells from LNC preparations but also a proportion of other cell populations including Ig‐bearing lymphocytes. In addition to detecting a cytotoxic LNC population reactive towards tumour‐associated embryonic antigens (retained fraction from nylon‐wool column separation), a subpopulation of multiparous rat LNC was demonstrated in cell fractions eluted from the nylon wool which was shown to suppress the cytotoxicity of the retained multiparous LNC population. The exact nature of this subpopulation of LNC and the mechanism of action is at present not known.
Studies on the uptake of 2‐deoxy‐d‐glucose in normal and malignant rat epithelial liver cells in culture
Authors: Siddiqi Maqsood , Iype P. Thomas
Published: February 2007

The rate of uptake of 2‐deoxyglucose in normal rat hepatic cells and chemically induced hepatoma cells in culture was studied. The hepatoma cells possessed a higher permeability to the sugar at all stages of culture. However, a decrease in the uptake of 2‐deoxyglucose at confluency was observed in cells which exhibited density‐dependent inhibition of growth, whether normal or malignant. The normal cells in mitosis showed an increased permeability to the sugar, whereas no such change was observed in the hepatoma cells. The kinetic studies of 2‐deoxyglucose transport in normal and transformed rat liver showed a positive correlation between the increase in Vmax and the transformed state of the cells, whether they were transformed in vitro or in vivo. No changes in the apparent Km were found, indicating that there are no qualitative changes in the transport sites. The results suggest that an increase in the number of sites involved in glucose transport is a characteristic of chemically transformed rat liver epithelial cells.
Epidemiological studies on feline leukaemia virus infection. I. A serological survey in urban cats
Authors: Rogerson Petrina , Jarrett William , Mackey Lindsay
Published: February 2007

A survey of the incidence of feline leukaemia virus (FeLV) infection in cats in a large urban area was made by studying the prevalence of antibodies to feline leukaemia virus‐associated cell membrane antigens. Two serological tests were used, immunofluorescence and a mixed immunoglobulin rosette technique. The overall incidence of cats with antibodies was 40%, contrasting with 6% in the surrounding rural area. Only 6% of urban kittens were positive while 50% of adults had antibodies. The incidence in adults rose from 29% at 5–6 months to 74% in cats over 3 years. Stray cats had an incidence twice as high as that of domestic pets. These results support and extend earlier findings that FeLV infection is common and is horizontally transmitted.
Inhibition of human leukocyte migration in agarose by KCl extracts of carcinoma of the lung
Authors: Boddie A. W. , Holmes E. Carmack , Roth Jack A. , Morton Donald L.
Published: February 2007

The leukocyte migration in agarose assay recently developed by Clausen (Clausen, 1971), was used to test 22 lung cancer patients against soluble extracts of allogeneic lung cancer and allogeneic normal lung. Seventeen were inhibited to a significantly greater degree by at least one tumor extract (average migration index MI = 0.58) than by the corresponding normal lung extract (average MI = 0.83). DNCB‐positive and DNCB‐negative patients reacted with equal frequency to tumor extracts. Three patients tested against their autologous tumor and normal lung extracts were specifically inhibited by the tumor extract (average MI = 0.53) but not by the normal lung extract (average MI = 0.83). None of seven lung cancer patients tested against non‐pulmonary tumor extracts was significantly inhibited (average MI = 1.1). Only 6/53 controls including patients with other tumors, patients with emphysema and age‐matched non‐smokers showed significant inhibition against any of the lung cancer extracts. These findings strongly suggest the presence of tumor‐associated antigens in KCl‐solubilized extracts of human lung cancer.
Induction of malignant lymphomas in swiss mice by N‐nitroso compounds formed in vivo
Authors: Börzsönyi Mátyás , Csik Márta
Published: February 2007

Malignant lymphomas were induced in Swiss mice treated intragastrically with methyl‐2‐benzimidazole carbamate (MBC, BCM, Carbendazim) and given sodium nitrite in their drinking water. The tumours appeared between 82 and 164 days after the beginning of treatment. In 30 mice given MBC and sodium nitrite, 10 lymphosarcomas were found. In the proliferating tumour cells, intracytoplasmic type‐A virus particles were demonstrated by electron microscopy. No tumours were found in animals given MBC only. The findings demonstrate the possibility of in vivo formation of N‐nitroso derivatives from MBC.
Are methylcholanthrene‐induced sarcoma‐associated, rejection‐inducing (TSTA) antigens, modified forms of H‐2 or linked determinants?
Authors: Klein George , Klein Eva
Published: February 2007

TA3Ha/MSWBS hybrid cells have been derived from the fusion of the TA3Ha ascites carcinoma (H‐2a) and the methylcholanthrene‐induced MSWBS ascites sarcoma (H‐2s). MSWBS expresses a strong tumor‐specific transplantation antigen (TSTA), capable of inducing a rejection reaction in the syngeneic A.SW host. The genetic determinants of the H‐2 complex are known to be localized on chromosome No. 17. TA3Ha contributes two normal, telocentric chromosomes No. 17 to the hybrid. In contrast, both chromosomes No. 17 of MSWBS are localized on readily identifiable translocations (17/1 and 17/M1; see Wiener et al., 1974). We have previously shown that the chromosomes No. 17 of one parental strain, or the other (but not both) can be removed from the hybrid by selective passage in the opposite parental strain. The present paper examined the possibility, often suggested in the literature, that the MC‐sarcoma‐associated TSTA could be a modified form of H‐2. MSWBS, unselected TA3Ha/MSWBS and YACIR/MSWBS hybrids were compared with TA3Ha/MSWBS‐derived isoantigen loss variants, with regard to their immunogenicity in the TSTA test, i.e. their ability to induce rejection of MSWBS target cells in ASW mice. Whereas the unselected hybrids were as immunogenic as the parental MSWBS line itself, two strain A compatible and two strain A.SW compatible variants which had lost chromosome No. 17 of the opposite strain showed a residual, but clearly weakened immunogenicity. Since there was no systematic difference between the reciprocal types, it is concluded that the genetic determinant of TSTA is not localized on the chromosome No. 17 but that a proper balance of this chromosome is required for the full expression of immunogenicity in the TSTA system.
The nature of the deoxyribonucleosides involved in the binding of carcinogenic hydrocarbons to the DNA of mouse embryo cells
Authors: Brookes P. , Jones Pamela , Amos Jacqueline
Published: February 2007

The DNA of mouse embryo cells was specifically labelled in the purine moieties with (G3H)‐deoxyadenosine or in the cytosine moieties with (53H)‐deoxycytidine. These cells were then treated with 7‐methylbenz (a) anthracene (7MBA) or benzo (a)‐pyrene (B(a)P) and the DNA isolated, degraded and fractionated by LH20 Sephadex column chromatography. When the purines of the DNA were tritium‐labelled, radioactive hydrocarbondeoxyribonucleoside products were obtained. No such products were found with deoxycytidine pre‐labelled DNA. Contrary to an earlier suggestion, these results indicate that it is the purine moieties of DNA which react with the metabolically activated hydrocarbon derivative in vivo.
Risk indicators in childhood malignancies
Authors: Salonen Tuula , Saxén Lauri
Published: February 2007

A series of 972 childhood malignancies was compared with a control series of healthy children matched for date and place of birth. Several variables were tested for possible aetiological significance. The information was obtained from the Finnish Cancer Registry and from the antenatal records of the mothers. No significant associations were found between the various types of malignancies and the variables studied. In the group consisting of all malignancies, a risk ratio of 2.0 could be significantly excluded for most variables. In the leukaemia group, both pelvic X‐ray and polio vaccination were associated with slightly elevated risk ratios, but the differences between this group and the matched controls were not statistically significant. BCG vaccination was performed during the perinatal period in 90% of the children, but the proportion was the same in the study and control groups, and hence the hypothesis that this vaccination confers protection was not supported. The information is considered prospective and relatively reliable, and the authors suggest that these data may be useful when more extensive series are compiled from various sources.
Lack of correlation between growth characteristics, agglutinability by plant lectins and the malignant phenotype
Authors: Berman Leonard D.
Published: February 2007

Wheat germ agglutinin and Concanavalin A were found to agglutinate a variety of normal hamster cells as well as a number of lines of transformed or tumor cells. The normal cells included preparations from embryos and neonatal organs, and the spontaneous line, BHK‐21 C13. In order to explore more fully the situation in regard to the BHK cells, three sublines were isolated and studied. A “flat revertant” selected by FUdR treatment grew to diminished saturation density and failed to produce colonies in soft agar in contrast to the parent line, which did. Yet, it was only minimally less tumorigenic and less agglutinable than the parent line. Lines derived from one and four consecutive in vivo tumor passages showed increased tumorigenicity and growth in soft agar when compared to the parent line. Although the first passage line showed increased saturation density, the saturation density of the fourth passage line was similar to or less than that of the parent cells. Agglutinability of these lines was not significantly increased. These results indicate that, in contrast to widely accepted beliefs, tumorigenicity may correlate poorly with growth characteristics and agglutination by plant lectins.
Chromosome banding anomalies in acute myeloid leukaemia
Authors: Fleischmann Tamás , Bodor Ferenc
Published: February 2007

Chromosome analysis in two cases of acute myeloid leukaemia are reported. On the basis of slight aberrations in the banding pattern marker chromosomes were observed in both cases. In one case a widened C‐band of an additional D chromosome, and in the other case an unusual negative fluorescent band below the centromere of one of the chromosomes 16, were seen.
Detection in colorectal carcinoma patients of antibody cytotoxic to established cell strains derived from carcinoma of the human colon and rectum
Authors: Schultz Richard M. , Woods Wilna A. , Chirigos Michael A.
Published: February 2007

Sera from eight of 15 patients with colonic carcinoma exhibited demonstrable cytotoxicity against an established cell strain derived from adenocarcinoma of the ileocecum, HCT‐8. Sera from 12 of 16 patients with rectal carcinoma were cytotoxic for an established cell strain derived from an adenocarcinoma of the rectum, HRT‐18. Patients with colonic carcinoma exhibited serum cytotoxicity against only the colonic target cells, whereas patients with rectal carcinoma gave significant cytotoxicity against both cell strains. This cytotoxicity was shown to be complement‐dependent and appeared to be specific for colonic and/or rectal carcinoma cells. Although the cells produced carcinoembryonic antigen (CEA) in vitro, the cytotoxic antibody response in these patients did not appear to be directed against CEA. Serum cytotoxicity was not demonstrated against two other cell strains, HCT‐48 and HT‐29, derived from adenocarcinomas of the human colon, except for a reaction against a blood‐group‐related antigen. These cell strains had comparable levels of cell‐associated CEA. The routine titration of cytotoxic antibody against these established cell cultures may provide meaningful information on the host's immune response to colorectal neoplasms.
Microscopical cancer of the stomach — a study on histogenesis of gastric carcinoma
Authors: Nagayo Takeo
Published: February 2007

In order to elucidate the histogenesis of gastric cancer preceded by “chronic gastritis”, 67 foci (58 cases) of minute cancer less than 5 mm in largest diameter were examined histologically. The results obtained were as follows. (1) Except in two cases, all minute cancerous foci were found unexpectedly in the mucosa of the antrum or of the angulus having peptic ulcer or gastric cancer. They were more frequent in the lesser curvature than in other parts of the stomach. (2) Histologically, 18 foci were found in an area close to the main lesion, while 40 were far from the lesion. Seven foci were detected in the mucosa adjacent to ulcer scars. (3) In retrospective macroscopical examinations, 41 foci showed minimal erosion or tiny depressions on the affected mucosa, while in the other 26 no recognizable changes were observable. (4) Histologically, the gastric mucosa outside the cancer lesions was more or less atrophic with or without intestinal metaplasia. (5) Regardless of histological types, all the minute cancers were found in the transitional zone between foveolar epithelium and pyloric glands corresponding to “generative cell layer” in autoradiographic studies. (6) Poorly differentiated adenocarcinomas containing signet‐ring cells occurred most often in combination with no or slight intestinal metaplasia of the mucosa, while well‐differentiated adenocarcinomas were always found in ventricles with severe intestinal metaplasia.
Inactivation of the dna template in HeLa cells treated with chlorambucil
Authors: Roberts J. J.
Published: February 2007

The effect of chlorambucil on the colony‐forming ability of HeLa cells following either treatment for 1 h or continuous treatment has been measured. Concentrations of chlorambucil which had only minimal effects on cell survival inhibited the rate of DNA but not RNA and protein synthesis within 1 h of treatment. Nevertheless, cells continued to synthesize DNA for many hours after this treatment in the absence of cell division. Synchronous populations of HeLa cells treated prior to DNA synthesis, in the G1 phase of the cell cycle, were not delayed in their progression into the S phase where they exhibited a marked dose‐dependent inhibition of the rate of DNA synthesis. Cells in which DNA synthesis had been depressed showed a prolongation of the S phase and this was accompanied by a corresponding dose‐dependent mitotic delay. Treatment during the G2 phase of the cell cycle did not induce any delay or block in the next mitosis, but did inhibit the rate of DNA synthesis in the following cell cycle in a dosedependent manner; this depression of DNA synthesis was followed by a delay in the next mitosis. Cross‐linking of either isolated DNA or DNA present in treated HeLa cells was demonstrated, and in the latter case calculated to be of the same order as that which occurred with other difunctional agents at comparable toxic concentrations.
Vaccination against feline leukaemia virus using a cell membrane antigen system
Authors: Jarrett William , Jarrett Oswald , MacKey Lindsay , Laird Helen , Hood Christine , Hay David
Published: February 2007

Cats inoculated with live feline lymphoblastoid cells of the FL74 line developed high titres of antibody to feline oncornavirus‐associated cell membrane antigen (FOCMA). Eight cats were subsequently challenged with a large dose of feline leukaemia virus (FeLV) of a highly pathogenic strain. All resisted infection while 10 cats given the challenge virus alone became infected. The FeLV produced by FL74 cells was shown to be of extremely low infectivity in cats and in cultured feline cells. Cats inoculated with either FL74 cells or virus purified from them did not become infected. The purified virus did not induce FOCMA antibody in cats not previously exposed to FeLV. The fact that FL74 cells are highly immunogenic, but produce virus of low infectivity, is of value in devising vaccines against FeLV. Cats were also inoculated with FL74 cells which had been inactivated with paraformaldehyde. They developed FOCMA antibody, reaching a peak titre of 256, and no virus could be cultured either from the vaccine preparations or from the tissues of the cats.
Comparison of 51Cr release and microcytotoxicity assays against human melanoma cells
Authors: Hersey P. , Edwards J. , Edwards A. , Adams E. , Kearney R. , Milton G. W.
Published: February 2007

Comparisons of the cytotoxic activity of mononuclear cells from venous blood of human subjects against human melanoma cell lines have been made by means of the 51CV release assay (CRA) and the microcytotoxicity assay (MCA) of Takasugi and Klein. The relative effectiveness of the two assays in the detection of killing by various sub‐populations of effector cells was studied after depletion of monocytes and separation of the blood monocluear cells by SRBC receptor and Fc receptor rosetting techniques. Overall, the results showed good correlation. Most differences were the result of low values recorded with the CRA when effector cells were obtained from Hypaque‐Ficoll—separated populations which had not been further fractionated. These differences were largely removed when monocytes were depleted by glass absorption and may reflect interference with the CRA by monocytes. No consistent differences were found between the assays in the detection of killing by subfractions enriched for T cells or B cells in this tumour system. The MCA appears to offer the advantage of greater sensitivity and possibly detection of a wider range of cytotoxic mechanisms but the CRA has a number of advantages of a technical nature which make it more applicable to routine assays in clinical studies.