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In vitro transformation of brain cells of hamsters at various ages was examined after the addition of bovine adenovirus type 3 to determine the type and origin of the target cells. Cellular transformations occurred only in cultures of fetus and newborn animals and at low incidences. Nine cell lines were obtained. Virus specific tumor antigens were demonstrated in the transformed cells. The present investigation suggested that bovine adenovirus type 3 might transform mesenchymal cells (ME cell) and that these cells are probably of meningeal or vascular origin. The histological picture of tumors following transplantation of the transformed cells resembled human primary sarcoma of the meninges and brain.

As a step in the elucidation of the mutual relationship between the degree of cancer progress and the antitumor activity of lymphocytes from different sites in cancer-bearing body, we isografted methylcholanthrene-induced tumor (MC-tumor) subcutaneously on the back of mice. The regional axillary lymph nodes, spleen and distant mesenteric lymph nodes were removed from these animals one, two, three, and four weeks later. We mixed lymphocytes prepared from these lymphatic tissues with primary MC-tumor culture cells and cultured together to estimate antitumor acitivity of lymphocytes from different sites. It has been found that a strong antitumor activity can be seen only in those regional axillary lymph node cells taken out one or two weeks after tumor transplatation and such an activity is weakened by three or four weeks. On the other hand, distant mesenteric lymph node cells one or two weeks after the transplantation have no antitumor activity as yet, while at the terminal cancer stage of four weeks there appears a stronger antitumor activity than that of regional lymph nodes. In the spleen, a strong antitumor activity can be observed in the third week after tumor transplantation, but the activity disappears by the fourth week. These findings support our previous findings in that for the tumor onset after the transplantation the antitumor activity seems to appear first in the regional lymph nodes, and when the tumor grows beyond a certain size, such an activity diminishes while it appears in further distant lymphatic tissues.

Adaptive changes in cardiolipin content were examined in Staphylococcus aureus 209P using the 32P pulse-labelling method. Cardiolipin synthesis showed increased adaptation when cells grown in normal medium were transferred into high NaCl containing medium. When S. aureus cultured in 10% NaCl medium was transferred back to normal medium, cardiolipin concentration decreased to the normal level within 3 hours. The catabolic rate of cardiolipin in the cells was much slower in the 5% NaCl medium than in normal medium. The cardiolipin synthetase activity was examined by isolated membrane fraction from S. aureus grown both in normal and 10% NaCl medium. The activity was higher by two-fold in membrane fractions from cells cultured in 10% NaCl-containing medium than in membranes from cells cultured in normal medium.

DNA-dependent RNA polymerases (EC 2.7.7.6) were extracted and partially purified form the nuclei of rat ascites hepatoma cells (AH-130) induced by 4-dimethylaminoazobenzene. The patterns of RNA synthesis and the properties of these enzymes were compared with enzymes from the nuclei of rat liver. The specific activity of RNA polymerase in the homogenate from the nuclei of AH-130 cells was the same as normal rat liver nuclei. RNA polymerase was solubilized from the homogenate at high ionic strength and separated into two forms by DEAE-Sephadex column chromatography. Enzymatic characterization showed that these enzymes corresponded to RNA polymerase I and II. RNA polymerase I more effectively transcribed native DNA than denatured DNA at low salt concentration, but at high salt concentration RNA polymerase I effectively transcribed denatured DNA. RNA polymerase II more effectively transcribed denatured DNA. In AH-130 cells the activity of RNA polymerase I was 4 to 5 times higher than RNA polymerase II, and in rat liver the activity of RNA polymerase I was 1.5 to 2 times higher than RNA polymerase II. The activity of RNA polymerase I in AH-130 cells may have increased by induction.

Life-spans of macroreticuloytes and macrocytic red cells were studied. Rabbits were made anemic by injecting phenylhydrazine. Peripheral blood rich in reticulocytes was drawn, labeled with 3H-amino acids, and injected back into the anemic animal. Autoradiographic observation on circulating red cells revealed that macroreticulocytes matured at nearly the same time as normal-sized reticulocytes but that the macrocytic red cells had a short life-span compared to normal-sized red cells.

Investigations were conducted on the life-span of "stress" reticulocytes and the fate of the early denucleated large-sized reticulocytes in circulating blood. Reticulocyte disappearance was examined after reticulocyte introduction into the vein and into the peritoneal cavity of polycythemic and normocythemic animals. The results indicated that these introduced reticulocytes matured to red cells by about 36 hours after injection under both the polycythemic and normocytehmic conditions. The large-sized reticulocytes disappeared by about 4 to 12 hours after introduction. The maturation of reticulocytes was largely arrested when the cells were introduced into the peritoneal cavity.

Cholesterol, cholesteryl esters, triglycerides and fatty acids as major neutral lipids and phospholipids were examined in quantitative analysis. The method consisted of three steps: (1) separation of lipids by one-dimensional thin-layer chromatography on silica gel plates; (2) elution of neutral lipids from scraped silica gel with chloroform-methanol (4:1); and (3) colorimetric determination of individual neutral lipids in eluates and phospholipids in silica gel. The conditions were modified for chromotropic acid reaction for determining triglycerides. Laurell's method for determining fatty acids was also modified to apply to quantitative thin-layer chromatography. The accuracy of the modified methods was well-defined as the absorbance values were on a linear curve. A quantitative study was made of the recovery of triglycerides and fatty acids after chromatography. Combining these modified methods and colorimetry for determination of cholesterol cholesteryl esters and phospholipids, the author established a micromethod for determining the major neutral lipids and phospholipids by thin-layer chromatography. Lipids from HeLa, S-3 cells were analyzed to examine the applicability of this method to tissues. The results indicated that the new method permitted a reliable estimation of the major neutral lipids and phospholipids from small amounts of tissues.

The effect of a specific rabbit antiserum to rat alpha-fetoprotein (AFP) was examined on the growth and the plating efficiency of AFP-producing rat hepatoma cells (AH70Btc Clone 10-5) in cultures. The addition of anti-AFP serum to the culture medium inhibited cell growth moderately and inhibited plating efficiency markedly, although no inhibitory effect of complexes of AFP and antibody to AFP was observed on cell growth. Anti-AFP globulin in the immune serum was demonstrated on the cell surface by fluorescent antibody technique. Several clones producing low levels of AFP were obtained by long-term treatment of the original Clone 10-5 cells with anti-AFP serum. These treated clones showed characteristics that differed from the untreated original clone 10-5 cells: The relative plating efficiency of the treated clones on agar plates containing 5% anti-AFP serum was higher than the original Clone 10-15 cells and the amount of AFP secreted by the treated clones was lower.

The effect of murine sarcoma virus of Moloney strain on central nervous system was examined morphologically in Swiss mice of different age. A single intracranial inoculation of cell-free virus solution resulted in the induction of characteristic intracerebral granulomas in 82.8% of the newborn to 5 day-old group, in 71.4% of the 6 to 10 day-old group, and in 68.0% of the 11 to 20 day-old group. The mean latency periods to tumor recognition were 16.5, 21.1, and 33.5 days, respectively. The granuloma consisted of inflammatory cell infilrations, reactive gliosis, and richly developed blood vessels. The lesions consistently contained numerous characteristic large round cells. In cases of long-survival, the findings included reparative changes, such as extensive gliosis, withdrawal of inflammation, and a decrease in the numbers of large round cells and blood vessels. These lesions were tentatively designated as "large round cell granuloma." The early foci of the granoloma were composed of proliferating glial cells and large round cells at the subependymal regions. Electron microscopically these large round cells had abundant intracytoplasmic fibrils quite similar to gliofibrils. Numerous C-type virus particles were present in the intercellular nad perivascular spaces, and occasionally budded from cell membranes of the large round cells and vascular endothelia. The large round cells were considered to be reactive astrocytes activated by biral infection. It was conclided that MSV-M was not a sarcomogenic but a granulomogenic virus in mice. Control animals showed no pathological changes.

We investigated the antitumor effect of purified natural human tumor necrosis factor-beta (nHuTNF-beta) produced by human acute lymphoblastic leukemia BALL-1 cells stimulated with HVJ on pulmonary metastatic tumors of Lewis lung carcinoma (3LL) transplanted into BDF1 mice. nHuTNF-beta showed antiproliferative effects on metastatic tumors in a dose-dependent manner when administered daily for 10 days by the intravenous route. Histological examination of the tumors treated with nHuTNF-beta revealed that the tumor size and number of metastases were much reduced. Lytic cellular changes, including cytoplasmic vacuolation, loosening of the intercellular junction and both cytoplasmic and nuclear swelling, were found, but tumor necrosis was not. These findings indicate a therapeutic effect of Grade IIa according to the histological criteria of Shimosato and Ohboshi. In addition, synergistic augmentation of the antiproliferative effects of nHuTNF-beta by natural murine interferon-alpha/beta (nMu-IFN-alpha/beta) or recombinant murine interferon-gamma (rMuIFN-gamma) was recognized by median effect plot analysis. The results suggested that nHuTNF-beta may well deserve clinical trial as a new immunotherapeutical agent for human cancer.

The biochemical characteristics of cathepsin B secreted from cultured human liver cancer cells were examined. The enzyme activity of culture medium against a synthetic substrate, N-carbobenzoxy-L-arginyl-L-arginine-4-methyl-coumaryl-7-amide, was dependent on the addition of cysteine, and the optimal pH was found to be 6.0. No activity was observed when the enzyme source was fresh medium not used for culture. These results suggest that the enzyme released from liver cancer cells is the thiol-protease cathepsin B. The molecular weight of the enzyme with 90% of the total activity was 40,000. Two cathepsin B molecules were found in liver tissue from patients with hepatocellular carcinoma (HCC); one was equivalent in size to the secreted enzyme, and a smaller one was the same as normal liver cathepsin B (27,000), which was also obtained from HCC-bearing cirrhotic liver. These results demonstrate that two molecules of cathepsin B are synthesized in liver cancer, and that the larger one is released into the surrounding tissue.

Co-cultivation of thymus and spleen cells of Fisher and Lewis rats with lethally irradiated MT-2 cells harboring human T-cell leukemia virus type I (HTLV-I) resulted in the establishment of lymphoid cell lines, FIRT-1, FIRS-1, LERT-1, and LERS-1, respectively. Cells of these cell lines had rat T-cell characters as demonstrated by the positive reaction to monoclonal antibodies (MAbs) to rat T cell antigens (Thy 1 and pan T). They lacked surface immunoglobulins and strongly expressed rat interleukin-2 receptor antigen (Tac) and Ia antigen. Karyotypic analysis revealed that they had the normal rat karyotype in early cultures, but showed marked aneuploidy after long cultivation. None of them expressed HTLV gag proteins (p19 and p24) or virus particles, but they contained HTLV-I proviral DNA monoclonally and weakly expressed pX gene products (p40x). They were not transplantable into syngeneic newborn rats.

In order to improve the postoperative prognosis of gastric cancer patients we have performed preoperative endoscopic intratumoral administration of various biological response modifiers. In the present study we have investigated the kinetics and the immune response augmenting effect of intratumorally injected PSK, a protein-bound polysaccharide preparation, by immunohistochemical methods using anti-PSK antibody and various other antibodies. PSK-containing cells were located in the tumor tissues and follicular marginal zones of regional lymph nodes. Intratumorally administered PSK appeared to be phagocytized by the histiocytes and to cause them to become antigen-presenting cells. These cells may play a major role in augmenting immune responses in gastric cancer patients.

In order to clarify the origin of JC virus-induced brain tumors in rats, the development of tumors was sequentially analyzed histologically and immunohistochemically. Twenty-two of 30 rats (73%), which were intracerebrally inoculated with JC virus within 24 h of birth (group 1), developed, as a group, 45 brain tumors after 12 to 26 weeks. Seventeen of 27 rats (63%), which were inoculated on the 7th day after birth (group 2), developed 37 brain tumors as a group after a time 12 to 40 weeks. The tumors were found exclusively in the cerebrum. The microtumors, which were defined as tumors less than 2 mm in diameter, were located in the subependymal plate around the ventricular system. The microtumors and most part of the macrotumors consisted of cells of undifferentiated neuroectodermal nature, showing nuclear palisades and Homer-Wright-pseudorosette-like structures. Some tumor cells of macrotumors had an astrocytic nature and were positive for glial fibrillary acidic protein, S-100, Leu 7, and vimentin. In conclusion, the target cells of JC virus in rats may be undifferentiated subependymal cells of the cerebrum. The tumor cells show partial glial differentiation as they grow.

To analyze the possible major T cell recognition site(s) of chironomid antigens, we established human T cell lines and clones (CD3+ 4+ 8-) reactive to soluble extracts of the adult midge of Tokunagayusurika akamusi (TAA) and/or Chironomus yoshimatsui (CYA). All T cell lines and clones proliferated heavily in response to relatively large molecular weight fractions of TAA (MW greater than or equal to 15,000). Nine clones reactive to TAA were classified into 3 groups according to reactivity, indicating the existence of at least 3 distinct T cell recognition sites in TAA. Five T cell clones responded to both TAA and CYA, although the two chironomid antigens were serologically distinct. We conclude that T cell recognition sites of chironomid antigens are different from B cell recognition sites in humans.

The rescue of infectious virus from nonproducer BH RSV(-) cells by chick cellular DNA was attempted in order to investigate the functional state of endogenous and exogenous retroviral genes integrated within the cellular DNA. No infectious virus was rescued by transfection with DNAs of chick helper factor (chf)-negative chick embryo cells (CEC), chf-positive CEC or uninfected CEC producing endogenous Rous associated virus (RAV-0). On the other hand, infectious Rous viruses with the phenotype of RAV-0 and RAV-1 were rescued by transfection with DNAs of CEC which had been infected with RAV-0 and RAV-1. From these results, it seems that exogenous retroviral genes integrated in the cellular DNA are expressed rather easily by transfection while those present endogenously are not.

We performed a cytogenetic study on 140 nonpolymalformed patients with mental retardation of clinically undefined origin, using a high resolution banding technique, to determine how much chromosome abnormalities contribute to the etiology of this condition. A total of 15 patients (10.7%) were found to have autosomal or sex chromosomal abnormalities. Autosomal abnormalities included partial monosomy (5 cases), reciprocal translocation (one case), 13/14 robertsonian translocation (3 cases), unbalanced translocation (one case), inverted duplication of 15q (one case) and mosaic trisomy 21 (one case). Sex chromosomal abnormalities comprised structural rearrangement of the short arm of the X chromosome (one case) and 47, XXY in a pure or mosaic form (two cases). It should be noted that four out of the 5 cases of partial monosomy had subtle interstitial deletions, which might have been unidentified by the conventional G-banding method alone. In one case of the robertsonian translocation 46,XY,t(13;14)/45,XY,t(13;14), a small deletion was thought to have occurred in the cells with a chromosome number of 45. Comparison of clinical features of the 15 chromosomally abnormal patients with those of patients with normal karyotypes did not show any clinical parameter indicative of chromosome imbalance. These results suggest that a subtle chromosomal deletion is specific to mental retardation associated with few malformations. We believe that diagnostic evaluation of mentally retarded patients, even if nonmalformed, should include chromosome analysis using a high resolution banding technique.

A case of ovarian leiomyoma is reported, together with histologic, immunohistologic and electron microscopic findings. A solid firm tumor, measuring 6.5 X 5 X 5 cm, was found in the right ovary of a 65-year-old woman. The tumor had an obvious whorled pattern on the cut-surface. Well-differentiated, long spindle-shaped neoplastic cells revealed positive immunoreactivity for anti-desmin. Ultrastructural observations included numerous microfilaments with dense patches in the cytoplasm, micropinocytotic vesicles beneath plasma membranes and continuous basal laminae around neoplastic cells. These findings were compatible with leiomyoma. The possible histogenesis of ovarian leiomyoma was discussed.