bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of cyclophosphamide on in vitro correlates of tumor immunity
Authors: Steele G. , Sjögren H. O. , Ankerst J. 
Published: February 2007

AbstractThe effects of cyclophosphamide (CY) on tumor immunity against isografts of rat sarcomas induced by polyoma virus were studied using in vitro techniques. Groups of sarcoma‐bearing animals received CY (250 mg/kg intraperitoneally 11 days after isografting) CY (150 mg/kg IP 8 days after isografting), or IP injections of 0.9% NaCl. In control rats tumor growth was progressive. All CY‐treated animals showed transient tumor regression of at least 50% of their pretreatment tumor volume. Despite a drastic depression in numbers of blood leukocytes as well as lymph‐node cells following CY treatment, animals treated with 150 mg/kg CY were shown to have blood lymphocyte and lymph‐node cell cytotoxicity in vitro against plated sarcoma target cells comparable to untreated sarcoma‐bearing animals. Sera obtained from sarcoma‐bearing rats prior to CY treatment specifically blocked lymphocyte cytotoxicity against sarcoma target cells. After CY treatment serum blocking activity could not be demonstrated during the period of tumor regression, but reappeared in parallel with tumor regrowth. Antibodies cytotoxic to sarcoma target cells when homologous complement was added could not be demonstrated in sera obtained from animals before CY treatment, but were present after treatment during tumor remission. Following CY treatment, sera obtained from treated animals, when mixed with blocking sera from control animals, could counteract or unblock the blocking activity of tumor‐bearer sera. Unblocking capacity was present only in sera obtained during CY‐induced tumor remission. Serum IgG concentration was significantly and temporarily decreased after CY treatment.
Chromosome analysis and agglutination by concanavalin A of primary simian‐virus‐40‐induced tumors
Authors: Lehman John M. , Bloustein Paul 
Published: February 2007

AbstractTumors induced by SV40 virus in newborn and adult Syrian hamsters were analyzed for their growth properties in vitro, transplantation, agglutination with concanavalin A and chromosome constitution. Following transfer to culture flasks tumor cells grew for 2‐3 weeks, then went through a “degenerative phase”. Eventually lines were established which became adapted to in vitro culture conditions. Agglutination properties of these tumor cells were similar to those of cells transformed in vitro with SV40 virus. Of five subcutaneous and six intratesticular tumors that were analyzed for their chromosome constitution, all had a hypotetraploid chromosome number distribution. The results of the chromosome studies suggest a similar pattern in the evolution of malignant properties of cells transformed in vitro and in vivo following infection with SV40 virus.
Inhibition by streptovaricins of rauscher leukemia virus splenomegaly
Authors: Borden Ernest C. , Carter William A. , Sensenbrenner Lyle L. , Owens Albert H. , Lichtenstein Judith , Gray Gary D. , Neil Gary L. , Nichol F. Richard , Li L. H. 
Published: February 2007

AbstractStreptovaricins (Sv), ansa macrolide antibiotics, inhibited Rauscher leukemia virus (RLV) splenomegaly by 25‐50%. All streptovaricins tested were effective when administered orally either by diet ad lib or by intubation from infection to time of killing. When delivered by intubation, Sv wus measurable in plasma. For up to 6h. SvC, at 300 mglkglday, reduced mean splecln weight of infected mice, from 478±51 (SE) mg to 300555 (SE) mg. Rijampicin, at 250 mglkglday, had no similar activity. Decrease in caloric intake and in body‐weight gain also resulted in an inhibition of RL V splenomegaly; although Sv‐treated mice gained weight, the increase was usually slightly less than controls. However, mice treated with a Sv diet for a week prior to infection, after an initial period of weight loss, gained at a rate equivalent to a controlgroup, and when killed had a marked reduction in splenomegaly. The selectivity of streptovaricins and specificity for viral events was suggested by several observations: (I) Splenomegaly and mortality, induced by L1210 or a non‐injective transplantable tumor of RL V oriAjin, was not inhibited. (2) No inhibition of normal hematopoietic spleen colonies was observed. (3) Host immune responses, including cellular and humoral immunity and interjeron production and action, were not inhibited. Thus, although the effect of slightly decreased weight and intake could not be unequivocally established, the findings were most compatible with a selective inhibition of RL V splenomegaly by Sv.
Leukocyte adherence inhibition as measured by a radioisotopic technique for detection of cell‐mediated tumor immunity
Authors: Pierce G. E. , Devald B. L. 
Published: February 2007

AbstractIt has been previously reported that cell‐mediated tumor immunity may be detected by leukocyte adherence inhibition (LAI) as determined by a visual counting technique in the presence of soluble tumor antigen. In the present experiments leukocyte adherence was measured by a radioisotopic technique. Peripheral blood mononuclear cells from Wistar/Fu rats and lymph‐node cells (LNC) from C3H/J mice were labelled with Technetium 99m (99mTc) and incubated with medium alone and with medium containing tumor antigens (high dilutions of dialyzed tumor homogenates) in the wells of plastic tissue‐culture plates. After incubation, fluid and non‐adherent cells were removed. The ratio of residual radioactivity in wells with antigen to that in wells without antigen was determined. Adherence of blood mononuclear cells from rats bearing syngeneic transplants of a polyoma‐virus‐induced tumor was inhibited by dialyzed homogenates of this tumor. Adherence of blood mononuclear cells from normal rats was not inhibited. Adherence of LNC from mice bearing syngeneic transplants of a 3‐methylcholanthrene (3‐MCA)‐induced fibrosarcoma was inhibited by dialyzed homogenates of this tumor. Adherence of LNC from normal mice or from mice bearing a different 3‐MCA‐induced tumor was not inhibited. These results support the use of LAI as a simple test for cell‐mediated tumor immunity. Measuring relative leukocyte adherence with the radioisotope 99mTc eliminates possible bias in counting and permits multiple replicate determinations with a small number of leukocytes.
Cytotoxic effect of lymphocytes from pregnant mice on cultivated tumor cells. I. Specificity, nature of effector cells and blocking by serum
Authors: Hellström Ingegerd , Hellström Karl Erik 
Published: February 2007

AbstractLymph‐node and spleen cells from pregnant BALB/c mice were found to be cytotoxic (by a microcytotoxicity assay) to cultivated syngeneic tumor cells. Target cells included a series of in vitro transformants derived from BALB/c 3T3 cells (3T3‐MSV, 3T3‐SV40 and 3T12), as well as two lines of tumors induced in vivo. Skin fibroblasts and nontransformed 3T3 cells were not similarily affected. The cytotoxic lymphocyte effect was decreased by treatment with anti θ serum and complement but was not removed by passage through a column removing cells with immunoglobulin at their surface. It could be blocked by serum taken from pregnant mice and from mice carrying methyl‐cholanthrene‐induced sarcomas. These sarcomas could be different from the ones used as targets in vitro, but the blocking effect was higher when serum was tested from mice carrying the respective tumor studied. The blocking activity of serum from pregnant mice was removed by absorption with neoplastic cells, taken either from culture or directly from mice, and with fresh embryonic cells, but not to the same extent by absorption with explanted fibroblasts, 3T3 cells, or adult kidney cells. Absorption was most effective when the same line of cells was used as targets. Both the cytotoxic lymphocyte effect and the blocking serum activity were seen already during the first pregnancy and lasted for at least 1 month subsequent to delivery. Serum from pregnant mice could „arm”︁ control lymph‐node cells and produce a lymphocyte‐dependent cytotoxic effect on neoplastic, but not on control, target cells.
Pilot experiments with eb virus in owl monkeys (aotus trivirgatus). III. Serological and biochemical findings in an animal with reticuloproliferative disease
Authors: Epstein M. A. , Zur Hausen H. , Ball G. , Rabin H. 
Published: February 2007

AbstractNucleic acid hybridization with EB virus complementary RNA has demonstrated unequivocally that EB virus DNA is present in the cells of a continuous lymphoblastoid line established in culture from a pathological lymph node of an owl monkey with reticuloproliferative disease after inoculation with EB virus. There were 48 to 49 EB virus genome equivalents per cell. In addition, serological studies showed that the diseased owl monkey developed specific antibodies to EB virus capsid antigens. The antibodies were first detected by indirect immunofluorescence in serum sampled 13 weeks after inoculation, and were not found in sera from other animals without the disease. None of the monkeys developed heterophile antibodies. The significance of the biochemical and serological findings is discussed in relation to the nature of the reticuloproliferative disease and the possibility of tumour‐induction by EB virus.
Cytotoxic effect of lymphocytes from pregnant mice on cultivated tumor cells. II. Blocking and unblocking of cytotoxicity
Authors: Hellström Ingegerd , Hellström Karl Erik 
Published: February 2007

AbstractSera from BALB/c mice transplanted with either of two syngeneic, methylchol‐anthrene‐induced sarcomas (1315 and 1321) were found to block (i.e. abrogate) the cytotoxic effect of lymph‐node cells (LNC) from multiparous mice on cultivated tumor cells. The blocking activity was seen even at high serum dilutions (up to 1:320). It was found to persist in mice whose tumors had been removed 8–11 days previously. These mice had transplantation resistance against individually unique antigens of the respective sarcoma to which they had been immunized, but not against any common, putatively embryonic ones. In keeping with this finding, their sera did not block LNC‐mediated cytotoxicity to the unique transplantation antigens, when tested 8–11 days after removal of the immunizing tumor. Sera from rabbits immunized with BALB/c embryonic tissues and subsequently absorbed with normal adult BALB/c cells, were found to cancel („unblock”︁) the blocking activity of serum from multiparous mice. The specificity of this unblocking effect and its potential usefulness as a tool to study immune reactions to embryonic tumor antigens need to be established.
Occurrence of nervous‐tissue tumors in cattle, horses, cats and dogs
Authors: Hayes Howard M. , Priester William A. , Pendergrass Thomas W. 
Published: February 2007

AbstractFrom 11 North American veterinary university hospitals and clinics, 248 animals with a confirmed diagnosis of nervous‐tissue tumor were identified; 7 tumors were found in cattle, 28 in horses, 14 in cats, 199 in dogs, and none in other species. Tumors were divided for analysis into three categories—glial, meningeal, and peripheral nerve. In cattle and horses, all tumors involved peripheral nerves, the risk of which, in horses, reached a plateau at 4–6 years of age and remained constant thereafter. In cats, the tumors were equally distributed among the three tumor categories whereas, in dogs, twice as many glial tumors as meningeal and peripheral nerve tumors were found. The risk for glial tumors in dogs reached a peak at 10–14 years of age, for meningeal at 7–9 years, and for peripheral nerve at 2–3 and 7–9 years. Three canine breeds—English bulldog, boxer, and Boston terrier— had an excessive risk of glial tumors. Except for an excess of skin tumors in dogs with peripheral nerve tumors, there was no unusual occurrence with second primary neoplasms for any species. There was no detectable predisposition by sex for any of the categories of nervous‐tissue tumors among any of the four species. The role of genetic abnormalities associated with nervous‐tissue tumors and other etiologic factors (e.g., chronic hypoxia) may be clarified by further studies involving canine breeds of „bulldog”︁ ancestry.
Infectious dna recovered from avian tumor‐virus‐producing cells
Authors: Vigier P. , Montagnier L. 
Published: February 2007

AbstractA single treatment of chick embryo fibroblasts with DNA recovered from chick embryo fibroblasts productively infected and transformed with four different strains of RSV, or productively infected with two different strains of RAV, resulted in virus production and cell transformation (in the case of RSV) two or three passages after treatment (8–25 days). The virus recovered from cultures was phenotypically identical to that produced by the donor cells. No virus production nor cell transformation resulted from treatment of control cultures with DNA digested with DNAse. Infectious RSV‐DNA was recovered from purified donor cell nuclei and was associated with the precipitable fraction of DNA prepared according to the method of Hirt (1967). It also sedimented with cellular DNA in density gradients, and with high molecular weight DNA (2–4 × 107 daltons) in sucrose gradients, which suggests that it is associated and may be integrated with chromosomal DNA. In some experiments, DNA fractions of lower molecular weight (down to 6 × 106 daltons) were also infectious. DNA from virus‐producing RSV‐transformed cells also gave rise to virus and Rous cells in cultures of fibroblasts from gs‐ embryos. However, the amount of DNA required for successful infection varied widely between experiments, and no reproducible dose‐effect relationship was observed. The frequency of DNA‐treated cells which produced virus remained low, even when the assay cultures were pretreated with 5‐bromodeoxyuridine.
Effect of testosterone and estradiol‐17β on synthesis of dna, rna and protein in human breast in organ culture
Authors: Finkelstein Michael , Geier Avraham , Horn Hadassa , Levij I. S. , Ever‐Hadani Pnina 
Published: February 2007

AbstractEffects of testosterone (T) and estradiol‐17β (E2) on the synthesis of DNA, RNA and protein were studied in explants of the following types of malignant and non‐malignant human female breast grown in organ culture: cystic mastitis (7 cases), fibroadenoma (8), carcinoma (17) and uninvolved tissue from cancer‐bearing breast (8). In cultures of cystic mastitis T uniformly inhibited the incorporation of thymidine‐3H into DNA, uridine‐3H into RNA and L‐amino acids‐14C (AA‐14C) into protein. E2 inhibited the incorporation of thymidine‐3H, but had a variable effect on the incorporation of uridine‐3H and AA‐14C. Cultures of fibroadenoma, with no steroid added, were highly proliferative especially at the outer surface, but the incorporation of thymidine‐3H, uridine‐3H and AA‐14C was much lower than in cystic mastitis. Whereas in fibroadenoma T uniformly inhibited the synthesis of DNA, RNA and protein, the effect of E2 was variable: in most cases it inhibited the synthesis of DNA, but in one it stimulated it appreciably; in the majority of cases E2 stimulated RNA and protein synthesis. In cultures of cancerous tissue T depressed, in most cases, the incorporation of thymidine‐3H, uridine‐3H and AA‐14C, but it stimulated it in 4 out of 17. E2 inhibited the synthesis of DNA, RNA and protein in 6 cases (2 of them were inhibited by T), stimulated them in 9 (one stimulated by T) and had no clear effect in 2. The effect of the steroids on the explants of uninvolved tissue was variable and did not always parallel their effect on the cancerous tissue from the respective patients.
Antigens associated with chemically induced intestinal carcinomas of rats
Authors: Martin F. , Martin M. S. , Bordes M. , Knobel S. 
Published: February 2007

AbstractRabbits were immunized with extracts of primary or grafted intestinal adenocarcinomas induced by carcinogenic drugs in inbred rats. After absorption with normal tissue extracts, the antisera were able to recognize three tumor‐associated antigens. Two of them were glycoproteins, present in cancer cells but also, in trace amounts, in mucous cells of the normal digestive tract. The third antigen is not detectable in the normal digestive system, but present in normal spleen; on immunofluorescence, it is not located in the cancer cells, but in polymorphonuclear cells infiltrating the tumor. None of the three antigens cross‐reacts with human carcinoembryonic antigen, or human or rat alphafetoprotein. On the other hand, one of the glycoprotein antigens is immunologically related to the human blood group A substance.
Defects in cell‐mediated immunity during growth of a syngeneic simian virus‐induced tumor
Authors: Howell Stephen B. , Dean Jack H. , Law Lloyd W. 
Published: February 2007

AbstractFour assays of tumor‐specific cell‐mediated immunity were compared during growth of a syngeneic Simian‐virus‐40‐induced tumor, mKSA. Major differences were found in immunity detected by the tumor neutralization test (the Winn test), direct tumor challenge, the microcytotoxicity assay and the 51chromium‐release lymphocytotoxicity assay. Progressive growth of the neoplasm followed by loss of immunity (the eclipse phenomenon) was documented with the Winn test. It was established that this eclipse phenomenon represented a lesion in the T‐cell system of tumor‐bearing hosts. This lesion was found to be specific and unrelated to anatomic tumor location. The ability to produce graft‐versus‐host reactions, and the ability to respond to mitogens, were found to be generally intact in tumor‐bearing animals. Cells capable of recognizing mKSA tumor antigens and reconstituting an immune response following surgical removal of tumor or upon transfer to normal mice were found in the spleens of mice bearing advanced tumors. No suppressor cells that might account for the eclipse phenomenon could be demonstrated. Tumor‐bearer serum did not block neutralizing activity of immune spleen cells in the Winn test, and immune cells were capable of neutralizing tumor even in tumor‐bearing hosts. The possibility that the lesion is intrinsic to T‐cell precursors of effector cells is discussed.
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

AbstractStaphylococcus 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

AbstractVariation 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

AbstractN‐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

AbstractBy 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

AbstractBinding 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.