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The energy source required for the amino acid incorporation into mitochondrial proteins has been investigated and comparative study has also been made on the rate of the amino acid incorporation in rat liver and rat hepatoma cell mitochondria. 1. The incorporation of amino acid into the protein in intact mitochondria of rat liver increased by about 40% on the addition of α-ketoglutarate and ADP, but no significant increase in the amino acid incorporation was observed on the addition of succinate and ADP. 2. The incorporation of amino acids into mitochondrial proteins was remarkably inhibited by the addition of respiratory inhibitors (cyanide, DNP at a high concentration). 3. The amino acid incorporation into mitochondrial proteins was scarcely or slightly inhibited by the addition of DNP at the concentration of 1×10-4M and insensitive to oligomycin (5 to 10 μg/ml). 4. The amino acid incorporation into the protein in the endogenous substrate system of the mitochondria was considerably inhibited by the addition of arsenite, and this inhibition somewhat recovered on the addition of ADP plus succinate. 5. The rate of the amino acid incorporations between rat liver and hepatoma cell mitochondria was at the same level. 6. Discussions were made on the energy source required for the amino acid incorporation into mitochondrial proteins, on the rate of protein synthesis per mitochondrion isolated from rat liver- and hepatoma cells, and on the possibilities of contamination of bacteria or microsomes and of the adsorption of amino acids onto the mitochondria.

The synovial membranes from 16 rheumatoid patients treated with intramuscular injections of gold sodium thiomalate were observed by light and electron microscopy with special reference to the distribution of gold particles in the tissue. 1) Light microscopic study revealed that the gold demonstrated as cytoplasmic granules by OKAMOTO'S histochemical method were contained in the synovial lining cells and in the macrophages around lymph-follicles and blood vessels in the subsynovial layer. In the well-developed villi on the surface of rheumatoid synovial membrane, large macrophages with gold granules infiltrated into the lymphoid cell accumulation of small lymph-follicles. 2) The deposition of gold in the synovial tissue increased with the increase of the doses of gold administered. 3) Electron microscopic observation indicated that gold particles are contained in the numerous lysosomes in the Type A and intermediate lining cells. The macrophages around lymph-follicles and blood vessels also possessed a large amount of gold particles gathered in the lysosomes of these cells. 4) Macrophages containing gold particles in their long cytoplasmic extensions were found often in a close contact with plasma cells of various differentiation stages. A direct cytoplasmic connection was observed between the two kinds of cells but an artifact could not be excluded. 5) The effect of gold salt in the treatment of RA was discussed from the immunological view point.

The present investigation was conducted with the purpose to search for the specific cancer antigenicity at subcellular level, as its first object. The aim is on the immunochemical consideration and comparison of fractions such as cell homogenate, nuclei, mitochondria, microsomes, and plasma membrane etc. obtained by ultracentrifugation from cancer cells (AH 130 rat ascites hepatoma), and to compare the antigenicity of individual fractions from normal rat liver cells. 1. The highest antigenicity is found in the mitochondria in membrane systems of cancer cells. 2. The high antigenicity of mitochondria is cancer specific, and is not common to that of normal cell mitochondria. 3. The plasma membrane prepared from cancer cell nuclear fraction was a highly pure cancer cell plasma membrane. 4. As far as tested by precipitin reaction the antigenicity of the cancer cell plasma membrane is almost the same as that of normal cell plasma membrane, and it is hard to say that the antigenicity of cancer cell plasma membrane is cancer specific. Antigenicity of plasma membrane hardly diminishes at the stage of carcinogenic transformation of cells.

With the bone marrow of anemic rats, which had received the repeated injections of phenylhydrazine once a day for three to four days, the effects of aminopterin and bromouracil on the nucleic acid metabolism of erythroblasts were observed in vivo experiment. The injection of aminopterin suppressed DNA synthesis with the lowered labeling index as observed by the incorporation of ³H-thymidine into DNA in vitro. But the grain count per cell showed the level similar to that of anemic control. RNA synthesis was not interfered by AP injections. These results indicate that AP mainly suppresses the thymidilate kinase. Bromouracil showed no such effect even on the administration of a large dose. On the basis of the data obtained from the experiment by using AP, a discussion was made on the correlation between DNA synthesis, nuclear function and the cell specialization.

When cultured cells are used in experiments, It is very important to know from what kinds of cells the cultured cells are originated, and what characteristics the cultured cells maintain continuously in vitro Some properties of rat liver cells in long-term cultivation were examined for the purpose of identifying the cultured cells with parenchymal liver cells by investigating their functions. The production of rat serum albumin and α-globulin which is regarded as specific functions of liver parenchymal cells was detected in these cultured rat liver cells with the method of immunoelectrophoresis. Histochemically, acid phosphatase, glucose-6-phosphate dehydrogenase, succinic dehydrogenase, lactic dehydrogenase, and adenosine triphosphatase were demonstrated in the cultured rat liver cells which were morphologically epithelial. Alkaline phosphatase showed little activity in these cells. Glycogen was recognized by the periodic acid-Schiff technique, when bovine serum concentration in the culture fluid was reduced to 5 per cent. These histochemical findings of cultured rat liver cells were identical with those of parenchymal liver cells in vivo. These facts suggest that there is a possibility of the continuous cultivation of liver cells by the present methods and of the identification of the cultured cells with the parenchymal liver cells from their functions.

Human thyroid cancer cells in the pleural effusion were serially cultivated in vitro. Three kinds of cell lines were established from the same primary culture and were designated as PS, TS and TR lines, respectively. These three have been cultured for 574 days up to May 1, 1968. The cells of PS and TR lines were epithelial-like, whereas those of TS line revealed fibroblastic character. The chromosome numbers of PS and TR lines exhibited the modes near the hypertetraploid region, while TS line showed the mode of hypo-triploid number. Eosinophilic particles which were stained metachromatically by toluidine blue were present in the cytoplasm of these cells. The histochemical findings of the cells of each line were identical with those of thyroid cancer cells in vivo. The cells aggregated by the gyratory culture showed epithelial characters under microscopic observation of the sectioned specimens. The tumors produced in conditoned hamsters demonstrated undifferentiated cancer, which resembled the metastatic thyroid cancer of the patient. Neither collagen nor argentaffine fibers were detected with Van Gieson staining or silver impregenation.

The hepatomas of the Donryu rats induced by feeding 4.dimethyl. aminoazobenzene for more than 191 days were transplanted into the brain of newborn rats of the same strain and the formed tumors were transplanted into the peritoneal cavity of adult rat of the same strain for the purpose to obtain transplantable strain of ascites hepatoma. As the result 4 lines of transplantable ascites hepatomas have been establised. The cells of these 4 hepatomas resembled their original liver tumor cells, respectively, showing the similar morphologic appearance to their mother cell. They showed less differentiated or more malignant characteristics in those taken from the tumor at the more advanced stages of DAB feeding. The liver tissues from the rat fed on DAB for 191 days had no tumor inducing activity when they were inoculated into the brains of the newborn rats (C 74). The liver tumors of the rats fed for more than 236 days produced the tumors in brain, which was serially transplantable (C 82), and kept the original morphologic pattern through serial transplantation and even in those growing in ascites. The tumor cells of the C 82 line showed the least malignancy among the 4 lines of ascites hepatoma established. Those of the C 83 line, which originated from the rat fed on DAB for 264 days, demonstrated the type of well.differentiated liver cell carcinoma with the trabecular arrangement of the tumor cells, but in ascites form they grew more rapidly than those of C 82. Those having most malignant characteristics were the cells of C 84.A which were derived from the rat fed on DAB for 312 days, and they were of the type of undifferentiated liver cell carcinoma. The island forming capacity of the C 84·A cells was the weakest among those of the 4 lines. C 84·B cells were also those derived from the same rat as that from which C 84.A originated and also showed the type of poorly differentiated liver cell carcinoma, but less malignant than those of C 84.A.

The disappearance of nucleolus has been traced in the rat erythroid cells in relation with the cell specialization under varying conditions, i. e. in anemia with or without treatment by bromouracil and aminopterin. To make the findings more reliable the observations have been made on tissue section as well as on the smeared samples as the nucleolus becomes often indistinct in smeared cell. The results indicate that under anemic condition nucleolus is lost by the late basoplilic stage. Treatment with bromouracil retained the nucleoli and cytoplasmic basophilicity till later stage of cell specialization suggesting some similar mechanism of RNA disintegration both in nucleolus and cytoplasm.

Adl2-induced tumors were homogenized and fractionated by the SCHNEIDER'S method. The CF test with the serum from tumor-bearing hamsters revealed the predominant presence of T-antigen in the mitochondrial and microsomal fractions. Hence, the rabbit was immunized with the microsomal fraction of tumors, and its serum was used to prepare the fluorescent antibody to T-antigen. The direct staining of the tumor cells with so prepared fluorescent antibody gave a staining pattern similar to the indirect staining with the serum of tumor-bearing hamsters. It thus appeares possible to stain T-antigen by the direct immunofluorescent method using the serum of rabbits hyperimmunized with the microsomal fraction of Ad12-induced tumors.

It is said blastformation can hardly be observed in the tissue culture of mouse lymphocytes. However, in our experiments of mouse lymphocytes (obtained either from axillary or cervical lymph nodes) mixed with various cells in combination of other cells as A+C3H, A+C57BL, or C3H+C57BL, it has been verified that these lymphocytes readily undergo blastformation in the presence of PHA (phytohemagglutinin M) as adjuvant. In the single tissue culture of these lymphocytes without PHA, the blastformation is observable in 6 per cent of the cells, while in the presence of PHA it is seen in 13. 7 per cent of the cells. In the cases of mixed cultures blastformation is observable in 14 per cent in the absence of PHA, whereas it is seen in 35.4 per cent in the presence of PHA. There is obviously a significant difference (p=O.OOI) in the blast. formation when cultured in the presence of PHA, and its reproducibility also proves to be quite high.

As the results of investigating the antigenicities of various fractions from the membrane systems of cancer cells, it has been found that the remarkable cancer-specific antigenicity exists in cancer cell mitochondria. With a particular reference to this antigenicity of cancer cell mitochondria, the antigenicities of the mitochondria of various kinds of rat ascites tumors and those of tumor-bearing rat liver mitochondria have been compared with those of normal rat liver mitochondria. In addition, it has been demonstrated that a strong tumor antitransplantability is induced when the recipient rat is immunized with the tumor cell mitochondria. In order to support these experimental facts, enzymatic activities of cancer cell mitochondria have been investigated also biochemically after treating the mitochondria with the antiserum to these mitochondria. 1. The most remarkable cancer specific antigenicity exists in mitochondria among the membrane systems of cancer cells. This cancer mitochondria-specific cancer antigenicity is common to all the ascites tumor mitochondria used here. 2. The original tissue- or organ-specific antigenicities diminish or disappear at the carcinogenic transformation of cells. 3. The tumor-bearing-organ specific antigenicity appears in the organs of animals bearing tumor. 4. The tumor antitransplantability is acquired when rats are immunized with these tumor cell mitochondria. 5. The inhibition of mitochondrial ATP·ase and respiratory activities is observed when the cancer cell mitochondria are treated with the anti. serum to the mitochondria.

With the purpose to elucidate further the properties of the supernatant F4 obtained by centrifugation at 100, 000 g from the regional lymph node cells of the Cb mice sensitized with EHRLICH ascites tumor cells, the supernatant (cf. Report 13) was subjected to the following treatments:. The supernatant (F4) was first diluted variously with Hanks solution. 2. F4 was passed through Seitz filter. 3. Heated at 56°C for 30 minutes. 4. It was frozen and thawed. 5. Treated with O. 01 96 trypsin solution. Each of F4 frations so treated was used in the tissue culture of JTC-II cells (derived from EHRLICH cancer cells) as target cells. As a result we found that the antitumor factor passes th rough Seitz filter, and it loses its antitumor activity by 4-fold dilution or over. Likewise F4 loses its activity by freezing-thawing treatment as well as by trypsin treatment, while by heat treatment at 56°C for 30 minutes, it still retains its activity. From these finding, it is assumed that the antitumor factor contained in F4, fraction is not serum antibody but is a protein associated with the cell membrane.

For the purpose of revealing whether the sensitivity of the erythropoiesis to actinomycin D (AMD) differs among different animal species, and to see the acting site of AMD on erythroid cell specialization stage, the author observed the hourly change of the blood cell counts and bone marrow cells after AMD administration to mice, rats and rabbits, and obtained the following results: 1. The data indicated that the erythropoiesis of ra bbit is sensitive to AMD, as much as that of mice, while the rat is resistant to AMD, and its erythropoiesis is not affected by the similar dose of AMD as in the case of mouse and rabbit. 2. The morphologic observations on the eradication process of erythroblasts in the bone marrow of mice and rabbits indicates that AMD acts as to inhibit the transformation of the stem cell to the proerythroblast but not on the erythroblast in the course of specialization. The time required for the eradication coincided with the time of the proerythroblast to the mature red cell. 3. Discussion has been made on the possibility of the common stem cell to erythroid and granulocytic cells in relation to the lymphoid cells in bone marrow and their blast form.

It has been demonstrated that by the mixed cultures in the presence of PHA the combination of those cells whose H-2 antigens differ from each other shows a higher rate and more significant difference of blastformation than in the combination where non-H-2 antigens differ (Table 1). The blastformation observable in the combinations where non-H-2 histocompatibility antigens or sex.linked antigens are weaker, is not, so marked as the difference seen of the blastformation in the case with H-2 isoantigens. This in vitro lymphocyte stimulation test can be applied to the histocompatibility test in the combinations of strong H-2 antigens.

1. The cells used in the present experiments were lymph-node cells from inbred mice, and over 98 % cells were proven to be small lympho-cytes. Therefore, those cells that have undergone blastformation are all those derived from small lymphocytes. 2. When homogenate of one cell group is cultured with live cells of the other pairing group, there occurs blastformation. In the presence of PHA, such a blastformation becomes more marked. 3. The optimal concentration of PHA (phytohemagglutinin)-M added to the mixed culture is found to be 1% (v/v). 4. The maximum rate of blastformation in the mixed culture is observed at the culture hour 48, being much faster than in the mixed culture between two live cell groups. 5. In the mixed cultures between subcellular fractions prepared from cell homogenate by centrifugation and live cells, the transplantation antigenic potential (histocompatibility antigenic potential) is seen in the mitochondrial and the microsomal fractions, especially marked in the latter. 6. In the observations carried out by various combinations of these inbred mice, it has been demonstrated that the rate of blastformation induced by the addition of cell homogenate or sediment fractions prepared from the homogenate reflects quite accurately the differences in H-2 antigens.

1. A respiratory-deficient mutant strain of yeast was obtained from wild strain of Saccharomyces servisiae by treatment with 4-nitroquinoline N-oxide. Ultrastructure and function of the wild or mutant strains and the mitochondrial fractions isolated from these strains were examined by biochemical and electron microscopic analyses. 2. The frequency of the respiratory-deficient mutant strain in yeast induced with 10-6M 4-nitroquinoline N-oxide was about 40 %. 3. Respiratory-deficient mutant strain is incapable of reducing 2, 3, 5-triphenyltetrazolium chloride salt and to grow on lactate medium. In addition to this, the mutant has been found to have lost its ability to take up oxygen in sodium succinate and pyruvate. 4. 4.Nitroquinoline N-oxide in the concentration that induces a mutant of yeast cells or its kin inhibits the oxygen uptake in normal strain. 5. The normal strain of yeast is characterized by difference spectrum corresponding to cytochromes a+as, band c+Cll respectively, whereas, the mutant strain containes almost no cytochromes a+ as, band C1 but contains normal or increased amount of cytochrome c. 6. Mitochondrial fraction isolated from mutant strain has largely lost its ability to oxidize succinate. On the other hand, NADH-, lactate-and cytochrome c-oxidase activities are reduced by about 1/17, 1/7 and 1/8 of that of normal strain, respectively. 7. Succinate dehydrogenase activity of mutant strain is almost zero. Moreover, this activity is not affected on the addition of phenazine methosulfate. NADH dehydrogenase activity of mutant stran is about 1/2 of normal strain. 8. The variations in mitochondrial structure of normal and mutant strain in the stationary phase have been followed with the aid of electron microscopy. In contrast to the normal strain, the mutant strain revealed distinct morphological changes in mitochondria, especially, the lack of cristae in its interior. The results have been interpreted to indicate that the mutant induced by 4.nitroquinoline N.oxide has a character of cyto. plasmic mutant.

For the purpose of revealing whether or not hemoglobin synthesis is inhibited by the AMD, the author estimated the hemoglobin level of AMD treated anilmals by microspectrophotometer, and found that the hemoglobin levels of all the developmental stages of erythroid cells were not inhibited by the AMD. The data indicated that about one half of mRNA for hemoglobin is synthesized in the early stage of specialization with the supplementary synthesis at the later stages and all these mRNA is stable and insensitive to AMD.

For the purpose to confirm the existence of the stem cells of the myeloid and erythroid cells in the circulating blood and to have the information of its morphologic entity, the author conducted morphologic observations on the peripheral and bone marrow cells of the x-irradiated parabionts having non-irradiated partners joined by the vascular parabiosis devised by the author, and the following results were obtained. 1. The control rats exposed to 1000R x-ray did not show any sign of recovery of hemopoiesis in bone marrow even 8 days after irradiation. 2. In the bone marrow and spleen of the lethally irradiated animals having non-irradiated partner in parabionts, precursor cells of granulocyte and erythrocyte appeared first 4 days after conjugation irrespective of the days after irradiation, and the hemopoiesis was restored completely on the sixth to the seventh day. The results have indicated that the circulat. ing blood has the stem cells which can dedifferentiate and transform into the precursor cells of the myeloid and erythroid cells within 3 days under adequate conditions. 3. On the basis of the morphologic observations on the peripheral blood of the parabiosis and non-irradiated rats revealded non-specific cells, a discussion was made on the possibility that some atypical lymphoid cells can serve as the stem cells of the myeloid and erythroid cells.

Correlation of molecular structure with biochemical functions of the plasma membrane of the microvilli of intestinal epithelial cells has been investigated by biochemical and electron microscopic procedures. Repeating particles, measuring approximately 60 Åin diameter, were found on the surface of the microvilli membrane which had been isolated or purified from rabbit intestinal epithelial cells and negatively stained with phosphotungstic acid. These particles were proved to be inherent components of the microvillus membrane, attached to the outer surface of its trilaminar structure, and were designated as the elementary particles of the microvilli of intestinal epithelial cells. Biochemical and electron microscopic identification of these elementary particles has been carried out by isolation of the elementary particles with papain from the isolated microvillus membrane, followed by purification of the particles by chromatographies on DEAE-cellulose and Sephadex columns. The partially purified particles containing invertase and leucine aminopeptidase are similar in size and structure to those of the elementary particles in the microvillus membrane. Evidence indicates that each of the elementary particles coincide with or include an enzyme molecule such as disaccharidase or peptidase, which carry out the terminal hydrolytic digestion of carbohydrates and proteins, respectively, on the surface of the microvillus membrane. Magnesium ionactivated adenosine triphosphatase and alkaline phosphatase cannot be solubilized with papain but remains in the smooth-surface membrane after the elementary particles have been removed. Cytochemical electron microscopic observation revealed that the active site of magnesium ion-activated adenosine triphosphatase is localized predominantly in the inner surface of the trilaminar structure of the microvillus membrane.

We fractionated the red cells of Japanese acatalasemic individuals (four individuals in two families) by SAss's method and counted the number of reticulocytes and determined the catalatic activity by manometric and perborate methods on each fraction containing reticulocytes in the descending order from the upper to the lower layers. We also incubated each of these fractions at 37°C for 4, 10,24 and 48 hours, to see the catalatic activity along with the maturation of reticulocytes. Heat stability of catalatic fraction separated by DEAE column was also examined. The results of the study may briefly be summarized as follows. 1. a. There was no parallel relationship between the number of reticulocytes and the catalatic activity in Japanese acatalasemic red cells. b. There could be seen no decrease in catalatic activity while the number of reticulocytes did decrease by the incubation. 2. Heat stability of crude catalatic fraction from acatalasemic blood is approximately the same as that of crude catalase fraction from normal blood.