Effect of long-term administration of 4-(dimethylamino)azobenzene on liver cell line derived from rats fed this chemical

Liver tissue cells derived from rats fed 4-(dimethylamino)azobenzene (DAB) were maintained in vitro for several months. These cells showed higher malignancy after treatment with 4.8 or 19.2 mug/ml of DAB. Subcutaneous back-transplantation of DAB-treated cells showed an earlier appearance of palpable tumors and a higher rate of "take" than the non-treated control cells. The tumor size at 60 days after back-transplantation was also significantly larger in the DAB-treated cells. Long-term treatment with DAB produced few morphological changes of the cells in vitro, but the plating efficiency and resistance to toxic effects of DAB were significantly higher in the treated cells than in the control cells. On the other hand, no definite differences in chromosome number were found between the treated and control cells. These findings suggested that cell malignancy could be promoted by long-term treatment with DAB in vitro

Spontaneous malignant transformation in two epithelial cell lines of rat liver cells

The cellular morphology, chromosomal structure, and tumorigenicity of two lines (B and J-13) of rat epithelial cells were examined serially during in vitro cultivation. The cells for such cultures were derived from the hepatic tissues of two 7-day-old male rats of the Donryu strain. The cultured cells were first inoculated into newborn syngenetic rats on the 641st day in vitro (80th subcultures) for line B, and on the 446th day (58 subcultures) for line J-13. The inoculated cells produced tumors with hemorrhagic ascites in rats after long latent periods, viz, 215-599 days in line B and 170-369 days in line J-13. All the tumors were undifferentiated hepatocarcinomas. The pleomorphism in shape and size of the cultured cells gradually became obvious with time of cultivation and was more pronounced in recultured tumor cells. Chromosomes of the culured cells were a normal diploid pattern until about the 200th day in vitro, but thereafter the modal chromsome number shifted to hypodiploid or hypotriploid via hypodiploid stages. The chromosome constitution of recultured tumor cells resembled that of inoculated cells in number distribution, but had changed to a more complicated karyotype. In experiments with line B, the same marker chromosome was detected in all tumor cells analyzed as had been present in inoculated cells.

Effects of 3'-methyl-4-dimethylaminoazobenzene and 4-aminoazobenzene on plating efficiency, mitotic index, and macromolecular synthesis of cultured liver cells

The response of a cultured liver cell line to azo dyes was investigated by the application of 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) and 4-aminoazobenzene (AB) with observation of, in particular, the changes which occurred in plating efficiency, macromolecular synthesis and mitotic indices. The results were as follows. (1) The application of 3'-Me-DAB resulted in a decrease in size of colonies and plating efficiency of both J-5-2 cells (derived from 7-day-old rat liver tissues) and cells of the colonical clone, J-5-2cl. (2) AB caused greater inhibition of plating efficiency than did 3'-Me-DAB. (3) Both 3'-Me-DAB and AB inhibited synthesis of DNA but not of RNA or of protein. (4) AB exhibited a greater inhibitory effect on mitotic indices than did 3'-Me-DAB.

Preparation of anti-etiocholenic acid antiserum and anti-cholesterol succinate antiserum and their cross reactivities

Anti-3-hydroxy 5-androstene carbonic acid (etiocholenic acid) antiserum was obtained by immunizing rabbits with anetiocholenic acid-polylysine complex. Anticholesterol succinate antiserum was also prepared by immunizing rabbits with a cholesterol succinate-polylysine complex. The cross reactivities of these antisera were examined by means of radioimmunoassay system, immunolysis of liposome and passive hemagglutination reaction. Anti-etiocholenic acid antiserum was specific against the structure of ring A of cholesterol and the nature of OH group at C3 position and anti-cholesterol succinate antiserum was specific against the side chain similar to that of cholesterol.

Isozyme patterns of branched-chain amino acid transminase in cultured Morris hepatoma 7316A

Cultured cells from Morris hepatoma 7316A contained isozymes I and II, but not isozyme III, of branched-chain amino acid transaminase. They also contained tyrosine transaminase. Isozyme II and tyrosine transaminase were induced by addition of cortisol. These findings agree well with in vivo findings. However, prolonged culutre of the cells for over 500 days caused deviation of the chromosomal bumber and activity of both enzymes, and they were no longer affected by cortisol. A tumor formed by back-transplantation of the cells showed the typical isozyme pattern of rapidly growing hepatomas, such as Yoshida ascites hepatomas, i.e., isozymes I and III. These results were discussed in relation to change of gene expression during culture.

Erythrocyte rosette forming activity of macrophage

Erythrocyte rosette forming activities of the rat lung macrophage, peritoneal macrophage, Kupffer cells and expressed splenic cells were studied. The erythrocytes employed were fresh human red blood cell (RBC), fresh sheep RBC (SRBC), and tanned SRBC coated with bovine albumin or with bovine gamma-globulin. The macrophages were mixed with RBC at a ratio of 1 to 100 or 200 in gelatin veronal buffer or phosphate buffered saline. The experiments were carried out at 4 degrees C. No autologous serum nor anti-RBC serum was added to the experimental system. 10 to 20 per cent of the lung macrophages formed rosette and their entire surfaces were covered with RBC. The peritoneal macrophage and Kupffer cells were also capable of forming rosette with fresh SRBC as well as with SRBC coated with bovine albumin or with bovine gamma-globulin. Examinations for cell surface immunoglobulin of alveolar macrophage, peritoneal macrophage, Kupffer cells and splenic cells revealed that alveolar and peritoneal macrophages apparently possessed surface gamma-globulin and that almost all of these macrophages possessed surface immuno-globulin. In order to examine the effect of different natures of SRBC on in vivo phagocytosis, rats were immunized with SRBC by injecting various SRBC into the femoral or the portal vein and the hemagglutinin titer was studied. The maximum hemagglutinin titer was observed in the rat injected with fresh SRBC into the femoral vein and the minimum hemagglutinin titer was observed in the splenectomized rat injected with fresh SRBC and in the rat injected with SRBC coated with albumin or gamma-globulin into the femoral or portal vein. Immunological role of Kupffer cells was discussed.

Clinical significance of Congo red test

Clinical significance of Congo red test was studied, especially on its relation to the liver function and amyloidosis. No significant relationship was observed between Congo red test and Indocyanin green test in cases of various liver diseases except liver cirrhosis. Histological studies also revealed that there were no pathologic features specifically affecting Congo red index (CRI), even though CRI in cases of various liver diseases tended to be increased as compared with other diseases. As a cause of increased CRI which was seen most remarkably in cases of liver cirrhosis, obstructive change of the liver blood flow followed by the hepatic tissue damage is suspected. The concept that Congo red test is a kind of the hepatic excretory function test does not have, from our data, enough evidence. The present study confirmed our previous data on the fate of Congo red injected intravenously, which indicated that this test is one of the best tests available for RES function and this test is related mainly to Kupffer's cell rather than to the so-called hepatic excretory function. There were no cases which showed notable decrease of CRI in experimental amyloidosis and in clinical amyloidosis, and it can be said that Congo red test is not the best test for the diagnosis of amyloidosis.

Lympho-reticuloendothelial activity of early gastric carcinoma

The lympho-reticuloendothelial activities of 54 cases of early gastric carcinoma were studied. Morphological blastoid transformation of lymphocyte by the addition of phytohemagglutinin-P (PHA-P) was disturbed in half of the patients. The DNA synthesizing activity of lymphocyte was not stimulated by PHA-P in the cases of advanced carcinoma but it was stimulated in the cases of early carcinoma. The tuberculin reaction was negative in 30% of the cases of early carcinoma. The reticuloendothelial system (RES) activity studied through the congo red method revealed that 86% of the cases of early carcinoma had disturbed RES function.

Effect of anti-alpha-fetoprotein serum on growth and plating efficiency of alpha-fetoprotein-producing hepatoma cells in vitro

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.

Establishment and some biological characteristics of human hepatoma cell lines

Two cell lines of human hepatoma, HLE and HLF lines, were established in vitro from the hepatocellular carcinoma of a 68-year-old patient. One clone (HLEC) was obtained from a single HLE cell. The cells of HLE and HLEC were epithelial-like and both of these cells demonstrated glycogen granules in the cytoplasm when stained with periodic acid and Schiff reagent. Although HLF cells resembled fibroblasts in morphology, they appear to have originated from hepatoma cells, judging from epithelial characteristics in aggregates reconstituted by rotation culture and heterotransplantability. HLE cells produced alpha-fetoprotein until day 187 of culture, but HLF cells did not produce alpa-fetoprotein at any period examined. Chromosome number of both cell lines was distributed near the triploid range. HLF cells were transplantable into the cheek pouch of adult hamsters treated with cortisone acetate, but not HLE cells.

Preparation of single cell suspensions from hepatoma cells in culture

Fundamental examination was carried out on the liberation of single cells from hepatoma cells in culture. dRLa-74 cells derived from rat hepatoma, which hardly disperse as single cell suspensions with several proteolytic enzymes or EDTA alone, dispersed with a high yield of single cells by the combination of trypsin and EDTA. HUH-6 cells derived from human hepatoblastoma also showed similar results. The degree of cell dissociation by the combination was dependent on the incubation temperature or pH.