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Biomedical subjects

N Takeichi

Publications and source records attributed to N Takeichi.

At least 199 records · Page 11Linked to original sources
PubMed1979

"Sontaneous" neoplastic transformation in vitro: a form of foreign body (smooth surface) tumorigenesis.

Explants of subcutaneous connective tissue from adult BALB/c mice into plastic petri dishes were serially subcultured and tested for tumorigenicity in two ways: by the subcutaneous implantation of cells attached to plastic plates (1 by 5 by 10 millimeters), and by the subcutaneous injection of cells suspended in saline. Cells grown in vitro for 18 or more days before being implanted attached to a plastic plate (2.4 x 10(4) to 3.4 x 10(5) cells per plate) formed tumors after 24 to 79 weeks. The latent period before tumor appearance correlated inversely with the time spent by the cells in tissue culture. Cells inoculated in saline suspension (10 to 100 times the above number per plate) did not form tumors until after 84 days in vitro; plates alone did not induce tumor formation within more than 1 1/2 years of implantation. The tumors arising from the plate-attached cells were transplantable without plates and histologically appeared to be undifferentiated sarcomas. It is well established that smooth-surfaced foreign bodies, regardless of their chemical composition, will produce sarcomas when transplanted subcutaneously in rodents. We interpret our data, particularly the decrease in tumor latent period with time spent in tissue culture, as indicating that a smooth surface was acting as a carcinogen first in vitro (the surface of the tissue culture dish) and then in vivo (the surface of the plastic plate).

Animals↗
PubMed1979

Dissociation of anti-tumor immune responses in rats immunized with solubilized tumor-associated antigens from a methylcholanthrene-induced fibrosarcoma.

Soluble tumor antigens were prepared from chemically-induced rat fibrosarcoma KMT-17 cells by various methods [Na-deoxycholate (DOC), 3 M-KCI extraction, and crude membrane preparations by mechanical disruption]. Soluble tumor antigens prepared by DOC extraction (DOC-STA) could be detected by a radioisotopic footpad assay (FPA) and they showed the strongest antigenic activity in KMT-17 immune rats. Anti-tumor immune responses in rats previously immunized with DOC-STA were measured by FPA, Winn assay, and transplantation resistance. Significant responses detected by the FPA and Winn assay were demonstrated in rats immunized with DOC-STA. However, rats previously immunized with DOC-STA showed a significant enhancement of tumor growth when challenged with KMT-17 cells. This enhancement was specific for the tumor line used. Normal rats which received adoptive transfer of thymus and spleen cells from rats immunized with DOC-STA produced specific enhancement of tumor growth as compared with non-treated rats. Administration of cyclophosphamide before immunization with DOC-STA abrogated the enhanced tumor growth in the host. These results suggest that immunization with soluble tumor antigens specifically enhanced tumor grwoth by the induction of immunosuppressor cells. Dissociation between the anti-tumor immunity detected by the FPA and Winn assay and the enhanced tumor growth detected by transplantation resistance in rats immunized with DOC-STA is discussed.

Animals↗
PubMed1979

Temperature-dependent alteration in immunogenicity of tumor-associated transplantation antigen monitored via paraformaldehyde fixation.

Paraformaldehyde-fixed mKSA tumor cells of BALB/c mice were shown to retain tumor-associated transplantation antigen (TATA) activity to a degree comparable to that of X-ray-inactivated tumor cells under the optimal conditions of 1% paraformaldehyde for 30 min at 37 degrees. Unexpectedly, the TATA activity of cells fixed below 10 degrees was greatly reduced. This temperature effect was reversible. TATA activity was restored if the cells were returned to 37 degrees before fixation. Fixation at all temperatures for longer than 2 hr or at paraformaldehyde concentrations greater than 1% also caused a decrease in immunogenicity. Spleen cells from mice immunized with tumor cells fixed at 37 degrees were able to more effectively neutralize tumor growth in the Winn assay compared with those from mice immunized with cells fixed at 0 degrees. Immunization with paraformaldehyde-fixed tumor cells was completely specific. Mice immunized with an antigenically unrelated tumor were not rendered immune to tumor challenge. Fixed tumor cells could be stored for at least 1 month without loss of TATA activity.

Animals↗
PubMed1979

A thymus cell marker in murine leukemia virus-induced lymphomas of rats.

A specific marker for an immature population of thymus cells in the rat was shown by the rosette formation between thymus cells and guinea pig erythrocytes. This method was used to classify murine leukemia virus-induced rat lymphomas. Eight of nine Gross virus-induced rat lymphoma lines, which originated in the thymus, formed rosettes; whereas Friend, Rauscher, or Moloney virus-induced rat lymphoma lines, which originated in either the thymus, spleen, or mesenteric lymph nodes, did not form rosettes. The percentage of the total cells which formed rosettes in the Gross lymphoma lines decreased with in vivo passages. If the tumor cells were exposed to trypsin treatment, then the tumor cells would form rosettes. Lymphoma lines which lacked rosette-forming cells did not show rosette formation after trypsin treatment. An immunofluorescence test showed that none of the lymphoma lines induced by Gross, Friend, Rauscher, or Moloney viruses carried the surface immunoglobulin characteristic of B-cells. These results suggest that Gross lymphomas may be derived from the thymic cortex and that Friend, Rauscher, or Moloney lymphomas may be derived from either mature thymus cells (non-rosette-forming cells) or from a subpopulation of the B-cell series which does not have the surface immunoglobulin G receptor.

Animals↗
PubMed1978

Immunological characteristics of leukemia and lymphoma in allogeneic cell immunity: growth of syngeneic tumors in rats immunized with allogeneic cells.

The growth of transplanted tumors was strongly inhibited in syngeneic Wistar King Aptekman (WKA) rats immunized with allogeneic tumor cells from Donryu rats. This phenomenon of non-specific immunity against tumors is referred to as "allogeneic cell immunity". However, an exception to the "allogeneic cell immunity" was observed in leukemias and lymphomas. Four transplanted leukemia or lymphoma lines were not inhibited in syngeneic rats immunized with allogenic tumor cells. Furthermore, immunization with allogeneic leukemic cells had only a relatively weak inhibitory effect upon a syngeneic fibrosarcoma and no inhibitory effect upon leukemias. In WKA rats immunized with allogeneic lymphoid cells from Donryu rats, the growth of fibrosarcoma, but not of lymphoma, was inhibited. Using transplantation experiments, both fibrosarcoma and lymphoma were defined as antigenic tumors in WKA rats. Transplantation of mixtures of syngeneic tumor cells and allogeneic tumor cells in WKA rats confirmed the above findings. These results revealed that leukemia and lymphoma differ from non-leukemic tumors in regard to "allogeneic cell immunity".

Animals↗
PubMed1978

Immunological study of two stocks of Moloney sarcoma virus producing regressor and progressor tumors in C57BL/6 mice.

The immune response to progressor murine sarcoma virus (P-MuSV)2 and regressor murine sarcoma virus (R-MuSV) was analyzed by the radioisotopic footpad assay (FPA) for delayed hypersensitivity (DH) and by the membrane immunofluorescence assay for anti-tumor antibodies. In mice injected with P-MuSV, the footpad response remained at a low level for 7 weeks, while membrane immunofluorescence antibody titers reached their maximum levels after 5 weeks. By contrast, in mice injected with R-MuSV, the footpad response rose to a maximum by 4 weeks and membrane immunofluorescence antibody titers reached a maximum after 4 weeks. The adoptive footpad response reached its highest level in 2 weeks. A most striking difference between the P-MuSV and the R-MuSV systems was the lower immunogenicity of tumor cells induced by the P-MuSV as measured by the FPA. Considerable differences between the two stocks were also observed in oncogenic activity and tumor growth patterns. The P-MuSV contained one-tenth the amount of helper Moloney leukemia virus found in R-MuSV. Addition of more helper Moloney leukemia virus to the P-MuSV did not produce regressor tumors.

Animals↗
PubMed1978

Augmented immunogenicity of tumor cell membranes produced by infection with influenza virus as compared to Moloney sarcoma virus.

The tumor-associated transplantation antigens (TATA) of crude membrane extracts from SV40-transformed BALB/3T3 tumor cells lytically infected with influenza virus were markedly more immunogenic than were extracts from uninfected cells measured either by the ability to induce heightened resistance to tumorgraft challenge or by heightened lymphocyte-mediated cytotoxicity against tumor cells in vitro. When intact tumor cells (as opposed to membrane extracts) were productively infected with Moloney sarcoma virus, they were made so immunogenic that they would only grow in X-irradiated syngeneic animals. Yet crude membrane extracts from the Moloney sarcoma virus-infected tumor cells showed no increase in TATA activity analogous to that seen after infection with influenza virus. Thus, influenza virus augmentation of tumor membrane TATA may operate by a different mechanism than does the oncornavirus augmentation of intact tumor cell TATA reported by others. It appears that Moloney sarcoma virus and possibly other oncornaviruses cannot be used to augment the TATA activity of tumor cell membranes in the same way that other surface-budding viruses can.

Animals↗
PubMed1976

Salivary gland tumors in atomic bomb survivors, Hiroshima, Japan. I. Epidemiologic observations.

An epidemiologic investigation was undertaken in Hiroshima to study the relationship of salivary gland tumors to exposure to ionizing radiation. Two hundred and eleven cases examined between 1953-1971 were confirmed by a review of histologic specimens. Of these, 66 cases occurred in residents of Hiroshima City who were born before the A-bomb: 30 among A-bomb-exposed, and 36 in non-exposed individuals. The incidence of salivary gland tumors among the exposed individuals was significantly higher, 2.6 times greater than that among the nonexposed individuals for all tumors, and 10 times greater for malignant tumors. The incidence increased with proximity to the hypocenter for the directly exposed. An increased incidence was also found among early entrants, particularly those entering the city within 3 days of the A-bomb.

Adolescent↗
PubMed1976

Local adoptive transfer of antitumor cellular immunity to xenogeneic animals studied with a rapid radioisotopic footpad assay.

The antitumor cellular immune response to Gross virus-induced rat tumor cells in F344 rats, as measured by a sensitive radioisotopic footpad assay, was adoptively transferred to syngeneic rats and to xenogeneic irradiated BALB/c mice. Xenogeneic transfer was accomplished by the injection of a mixture of rat tumor cells and syngeneic spleen cells, peritoneal exudate cells, or blood lymphocytes from specific immune rats into the footpads of mice. Peritoneal exudate cells produced the strongest footpad reaction in xenogeneic recipients. Use of the xenogeneic adoptive transfer system in a bioassay for human antitumor immunity appeared feasible.

Animals↗
PubMed1976

Discussion paper: specific paralysis of the antitumor cellular immune response produced by growing tumors studied with a radioisotope footpad assay.

The kinetics of the antitumor cellular immune response of mice with progressively growing syngeneic tumors were determined in vivo using a quantitative radioisotopic footpad assay. A close correlation was found between the size of the tumor and the degree of the cellular immune response. An initial phase of cellular immune stimulation was followed by specific suppression and subsequent immunologic paralysis as the tumor grew larger. This immune paralysis was attributed to increased tumor load since a homogenate of an SV40 transformed fibrosarcoma injected intraperitoneally into tumor-immune mice specifically depressed their cellular immune response. The fraction of the tumor homogenate that brought about this depression was present in the high speed supernatant and pellet of a 3M KCl extract of the tumor. The specificity of the depression was determined in vivo by the radioisotopic footpad assay and in vitro by a 51Cr cytolysis assay. Unwashed spleen cells harvested from mice bearing large tumors were unreactive in a local adoptive footpad assay. However, reactivity could be restored by repeatedly washing the spleen cells.

Animals↗
PubMed1976

Effect of experimental immune atrophic gastritis on the induction of gastric carcinoma by X-irradiation in ICR mice.

Divided doses of 6,000 or 8,000 rad of X-ray were given to the gastric region of ICR/JCL female mice with immune atrophic gastritis produced by the injection with allogenic stomach antigen. The carcinogenic effect of X-rays for inducing gastric carcinoma was significantly increased by this method. Two points can be presented as its reason. First, the pyloric gland mucosa regenerating from injuries by immunization was exposed to the divided dose of X-rays. Second, the marked requirement of gastrin secretion attributable to severe injuries of parietal cell mass by immunization and local X-irradiation acted as a promoting factor on the induction of gastric carcinoma by X-ray for a long time through the trophic effects on the pyloric gland.

Adenocarcinoma↗
PubMed1976

Development of adenocarcinoma of the prostate in ICR mice locally irradiated with X-rays.

The pelvic region of male ICR/JCL mice 5 approximately 7 weeks of age was irradiated with 1,000 rad of X-rays for a total of 8 exposures ot determine whether such irradiation would induce prostatic carcinoma. Prostatic adenocarcinoma was observed in 5 of 135 animals which survived more than 12 weeks after the first X-irradiation. Because spontaneous development of prostatic adenocarcinoma has not been reported in mice, development of this carcinoma in these animals can be considered to be attributable to X-irradiation.

Adenocarcinoma↗
PubMed1976

Adoptive immunotherapy of a Gross virus producing lymphoma and a methylcholanthrene-induced fibrosarcoma in tolerant rats.

Immunological tolerance to Gross virus-specific transplantation antigens in rats given neonatae transfer of donor lymphoid cells beneath the kidney capsule of syngeneic recipient rats. Immune or normal donor cells invariably developed a cell-mediated immune reaction in kidneys of GV-tolerant recipients, presumably against GV antigens present on the surface of recipient lymphoid cells in the kidney. Spleen and lymph node cells from tolerant rats failed to develop a reaction in tolerant recipients, but developed a strong reaction to histoincompatible antigens in the kidneys of semisyngeneic tolerant rats. The immunologically tolerant state in the rats could be broken by adoptive transfer of spleen and lymph node cells from syngeneic rats immunized with GV-induced lymphoma cells. Immunotherapy of a GV-induced and also a GV-infected methylcholanthrene-induced fibrosarcoma growing in tolerant rats was successful when immune spleen and lymph node cells were administered i.p. 3 days after s.c. inoculation of 2 X 10(7) tumor cells in the case of the lymphoma, and 1 day after inoculation of 5 X 10(6) tumor cells in the case of the fibrosarcoma.

AKR murine leukemia virus↗
PubMed1976

Vasoformative sarcomas arising from BALB/3T3 cells attached to solid substrates.

The BALB/3T3 mouse embryo cell line, noted for its marked postconfluence inhibition of proliferation, anchorage dependence, and high serum requirement, and frequently studied as a prototype nontumorigenic "fibroblast" line that is compared with tumorigenic sublines transformed with various agents, produced tumors within 2 to 3 months when an average of 3 X 10(4) cells were implanted s.c. attached to 1- X 5- X 10-mm polycarbonate platelets. Plastic platelets alone produced no tumors after 1 year of observation. The tumors, as well as others arising from implants of BALB/3T3 cells attached to 3-mm glass beads, were given the histological diagnosis of "vasoformative saroma" because the tumor cells frequently formed vascular channels. The vasoformative pattern and the results of specific staining for reticulin and collagen support the likelihood that BALB/3T3 cells originated from endothelial cells rather than from fibroblasts. That the tumors were derived from BALB/3T3 cells and not host cells was proved when tumors arising in BALB/c X C57BL/6 F1 hybrids were shown to be transplantable to BALB/c but not to C57BL/6 mice. The cultured tumor cells showed loss of both postconfluence inhibition of proliferation and anchorage dependence. Evidence of the induction of endogenous oncornaviruses was obtained in only one of four tumors tested. These tumors also exhibited tumor-unique transplantation rejection antigens. We conclude that BALB/3T3 cells are preneoplastic and give rise to different spontaneously transformed clones bearing unique tumor rejection antigens when implanted in vivo attached to a solid substrate.

Animals↗