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Biomedical subjects

N Takeichi

Publications and source records attributed to N Takeichi.

At least 217 records · Page 12Linked to original sources

Karyotypes of vasoformative sarcomas arising from BALB/3T3 cells attached to polycarbonate plates.

Four vasoformative sarcoma in vivo tumor lines arising from the s.c. implantation of 3 X 10(4) BALB/3T3 cells attached to a 1- X 5- X 10-mm polycarbonate platelet were shown to be quite similar in chromosome constitution to the parental 3T3 line. All tumors contained the same marker chromosomes that were present in the parent BALB/3T3 cells. The findings conclusively showed that the tumors had derived from BALB/3T3 cells and not from host cells or from the in vivo fusion of the inoculated 3T3 cells with host cells. Each tumor line had a unique karyotype that was markedly more homogeneous than that of the parental BALB/3T3 cells, strongly suggesting that each tumor represented a separate clone. An M1 marker chromosome was consistently present in each of the four tumor lines but was present in only about 50% of the parent BALB/3T3 cells; it therefore appeared to be a distinct and stable feature of the tumors.

Animals↗

Accelerated regeneration of trypsin-treated surface antigens of simian virus 40-transformed BALB/3T3 cells induced by X-irradiation.

The antigens of SV40-transformed BALB/3T3 cells measured by a radioisotopic footpad assay after removal by trypsin treatment regenerated in vitro in 3 to 6 hr. After X-irradiation with 3000 R, however, the antigens were regenerated to normal levels within 1 h. X-ray doses of between 1000 and 5000 R accelerated the regeneration of cell surface antigens, while X-irradiation with the larger dose of 8000 R did not. X-irradiation of nontrypsinized tumor cells was without effect. Possible mechanisms of this phenomenon are discussed.

Animals↗

Local adoptive transfer to mice of human delayed hypersensitivity: reactions by the radioisotopic footpad assay.

Human delayed hypersensitivity to living BCG organisms and/or Varidase was adoptively transferred to mice and assayed in mice by a radioisotope footpad assay (FPA). A mixture of the antigen and peripheral blood lymphocytes from patients (positive skin reactions to PPD and/or Varidase) or healthy volunteers was inoculated into the footpads of lethally X-irradiated mice. A positive footpad reaction was accompanied by an increased leakage of the radiolabelled serum protein from the blood stream into the intercellular space at the site of inoculation, and was measured by the 'foot-count ratio', or radioactivity in the test foot divided by radioactivity in the contralateral foot. The intensity of the footpad reaction correlated directly with the skin test response of the human lymphocyte donors.

Adolescent↗

Salivary gland neoplasms following atomic radiation: additional cases and reanalysis of combined data in a fixed population, 1957-1970.

A reappraisal was made of the relationship between exposure to atomic radiation in 1945 and the occurrence of salivary gland tumors in heavily exposed survivors. This was made possible by the discovery of 8 additional patients; the total now reported consists of 30 cases. In those exposed to 300+ rads, the number of cases was significantly (p less than .01) greater than expected. This was found for the combined group and for malignant types, but not for histologically benign tumors. Our prior conclusion regarding the high-dose radiation effect upon salivary gland neoplasia remains unchanged in the reanalysis; however, our suggestion that younger persons were at significantly greater risk is weakened.

Adenoma, Pleomorphic↗

Local adoptive transfer of the antitumor cellular immune response in syngeneic and allogeneic mice studied with a rapid radioisotopic footpad assay.

The immunologic nature of the cellular immune response against tumor cells inoculated in the footpad of mice was studied with a rapid, quantitative, and specific assay. The results indicate: a) The antitumor cellular immune response could be transferred adoptively in syngeneic and allogeneic mice with specific immune thymus (T) lymphocytes isolated on nylon columns; b) T-independent cells of host origin were necessary for the manifestation of the antitumor footpad reaction; and c) there was a close correlation between immune responses detected by the footpad assay and those detected by transplantation techniques. The footpad reaction consisted of several nonspecific and specific components. Nonspecific factors disturbing the specific footpad reaction in syngeneic and allogeneic recipients were discussed.

Animals↗

Treatment of runting syndrome and prevention of primary lymphomas in friend virus-tolerant rats.

A series of experiments showed that the inoculation of spleen and lymph node cells from rats immunized with Friend lymphoma (WFT-13) CELLS INTO Friend virus-tolerant rats induced the runting syndrome in nearly all cases, and immunological tolerance to WFT-13 was not broken in any survivors. However, th inoculation of specific immune spleen and lymph node cells admixed with normal bone marrow cells suppressed the runting death. In addition, in these animals the primary lymphomas that ordinarily occur about 200 days after neonatal inoculation of Friend virus did not appear. The mixture of immune spleen and lymph node cells and normal spleen and lymph node cells or normal thymus cells was ineffective in preventing the runting death or the incidence of primary lymphoma. Spleen and lymph node cells from normal rats or rats immunized with antigenically different AH-66 cells were also without effect. Spleen and lymph node cells from rats immunized with sheep red blood cells had a relatively high incidence of the runting syndrome; a few survivors rejected the WFT-13 transplants and also did not develop primary lymphomas. These results suggest that a supplement of hematopoietic stem cells from bone marrow eill not only prevent the runting death of Friend virus-tolerant rats produced by inoculating immune lymphoid cells but will also prevent the expected occurrence of primary lymphomas.

Animals↗

Histopathology of regression of tumor metastasis in the lymph nodes.

A transplanted rat lymphosarcoma (SGT-4), induced by Gross virus and inoculated s.c. into the foot of a normal syngeneic rat, initially grew but ultimately regressed. The tumor cells metastasized to the regional popliteal, lumbar, and inguinal lymph nodes and formed massive metastatic foci there. These lymph node metastases also regressed spontaneously. However, in Gross-tolerant rats inoculated with Gross virus at birth, no regression was observed. Histopathologically, infiltration and proliferation of lymphoid cells, reticulum cells, and bifrocytes occurred in the regressing metastatic tumor in lymph nodes as well as in the regressing transplanted tumor in the foot. Only in lymph nodes of normal rats, in which tumor metastasis regressed, was the characteristic "starry sky" appearance observed. Our results suggest that regression of metastatic tumor in lymph nodes, as well as of transplanted tumor in syngeneic rats, was due to an immunological reaction by the host and that an immunological factor may be responsible for the "starry sky" picture.

AKR murine leukemia virus↗