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To identify diffuse mucosal changes which may precede the development of colorectal cancer and a possible indicator for detecting high-risk populations, we immunohistochemically studied cell-cycle events in crypts of normal-appearing rectal mucosa of patients with colorectal adenoma and cancer using an in vitro labeling method with bromodeoxyuridine (BrdU). Biopsy specimens of endoscopically normal-appearing rectal mucosa were obtained during colonoscopy from 20 patients with colorectal adenocarcinoma, 20 with adenoma, and 15 without apparent colorectal diseases. The specimens were incubated with BrdU in vitro, and labeled S-phase cells were identified immunohistochemically using a monoclonal antibody to BrdU. Modification of the BrdU-labeling pattern in the normal appearing rectal mucosa, such as the presence of BrdU-labeled cells at the mucosal surface or in the upper one-fifth of the crypt column, was observed in 15 of the 20 patients with adenocarcinoma, 17 of the 20 patients with adenoma and 6 of the 15 controls. This upward shift in the frequency of proliferating cells in the crypt was significantly higher in the patients with colorectal adenoma and cancer than in the controls, and may be used to identify subjects at high risk for colorectal cancer.

PSK (Krestin) is a protein-bound polysaccharide with antitumor and immunomodulatory activity. In this study, the effects of the oral administration of PSK were investigated on the natural killer (NK) activity of liver-associated lymphocytes and their subfractions separated by density gradient centrifugation, in WKAH rats with liver metastasis of KDA hepatoma. PSK was administered orally, at a dose of 500 mg/kg once a day for 3 weeks. The NK activity of nonparenchymal liver cells (NPLC) and their subfractions, including large granular lymphocytes (LGL), was markedly augmented by this treatment. The effects of oral PSK were also examined in CDF1 mice with liver metastases of Colon 26 adenocarcinoma; the survival of tumor-bearing mice was prolonged and both metastatic foci and liver weight were decreased. These results suggest that PSK may be effective for the suppression of liver metastasis through activation of liver-associated NK cells.

To clarify the events related to complement-mediated immune responses in human colorectal cancers, we immunohistochemically examined the distribution of decay-accelerating factor (DAF), CD59/homologous restriction factor 20 (HRF20), membrane cofactor protein (MCP) and terminal complement complex (TCC) in human colorectal adenomas and cancers, and then compared the findings with their distribution in normal colonic mucosa. In the normal mucosa, TCC was not present on epithelial cells. Whereas DAF and CD59/HRF20 were present only occasionally on the apical surfaces of normal epithelial cells, MCP was diffusely distributed on the basolateral surfaces of most epithelial cells of the colon. These findings suggest that MCP has a primary role in the regulation of complement activation on these cells. In adenoma cells, the expression of both DAF and CD59/HRF20 was enhanced. In cancer cells, the expression of CD59/HRF20 and MCP was diminished, whereas DAF expression was markedly enhanced. Since DAF was frequently stained in the lumen of the cancer glands, it was suggested that DAF was released into the colonic lumen in patients with colorectal cancer.

Previously, we reported that interleukin-2 (IL-2)-stimulated helper T cells produced an unknown soluble factor which induced dendritic cell-like differentiation in primary cultures of monocytic leukemia cells and we referred to this factor as dendritic cell differentiation factor (DCDF). In this study, we attempted to purify and characterize DCDF and investigated its biological effect on normal human monocytes. Gel filtration chromatography indicated that the molecular weight of DCDF is approximately 30-35 kDa. Chromatofocusing indicated that the isoelectric point of DCDF is approximately 5.0. DCDF, partially purified by subsequent gel filtration, chromatofocusing, and hydrophobic chromatography, significantly enhanced the HLA-DR expression of normal human monocytes and a human monocytic leukemia cell line, THP-1. This biological activity was not neutralized by any known antibodies to human cytokines. DCDF significantly amplified the T-cell stimulatory activity of monocytes in the allogeneic mixed leukocyte reaction (MLR). Moreover, DCDF significantly enhanced IL-1 beta and IL-6 production by monocytes in a dose-dependent manner. These results suggest that DCDF is a novel human cytokine which stimulates the accessory cell function of monocytes.

Cytotoxic lymphocytes, including natural killer cells, lymphokine-activated killer cells, and cytotoxic T lymphocytes, adhere to and lyse cancer cells by recognizing cell surface antigens. Among the cell surface antigens, intercellular adhesion molecule-1 (ICAM-1) and HLA class I antigen are important for the cytotoxic activity of lymphocytes. The ICAM-1 and HLA class I antigen were examined in gastric cancer cell lines MKN-28 and MKN-45 by flow cytometry to determine whether their expression on the cell surface is enhanced by interferon gamma (IFN-gamma). The cell expression rate [stained cells/10(4) cells x 100(%)] was only 10% in ICAM-1 and about 20% in HLA class I antigen without IFN-gamma, but reached 70% in ICAM-1 and up to 60% in HLA class I antigen after incubation with IFN-gamma for 24-96 h. This enhanced expression of cell surface ICAM-1 and HLA class I antigen by IFN-gamma might increase sensitivity for cytotoxic lymphocytes.

Immunotoxins composed of monoclonal antibodies (mAbs) and various toxins have been developed for the treatment of malignancies. We investigated the efficacy of three ricin toxin A-chain (RTA)-containing immunotoxins (ITs) conjugated from mAbs which recognize glycolipid asialo-GM2 and glycoprotein H-2d. These ITs retained the same immunoreactivity with mAbs. We evaluated the cytotoxicity of these ITs against mouse lymphoma cells L5178Y variants showing high (AA12,CC9) and low (27AV) expression of asialo-GM2. Anti-H-2d-RTA IT had the strongest cytotoxicity for all cell lines. Anti-asialo-GM2 (IgM)-RTA IT had stronger cytotoxicity than anti-asialo-GM2 (IgG3)-RTA IT. Anti-asialo-GM2-RTA ITs had different cytotoxicity against AA12 and CC9 cells. The establishment of appropriate anti-glycolipid mAbs may lead to effective immunotargeting therapy.

We studied the distribution of class 1 and class 2 major histocompatibility complex (MHC) antigens on bile duct epithelial cells in liver from patients with primary biliary cirrhosis (PBC) by an immunohistochemical method using monoclonal antibodies to HLA-ABC products and HLA-D subregion products (HLA-DR, -DP, -DQ). By light microscopy, the expression of MHC class 1 antigens (HLA-ABC antigens) was enhanced in PBC compared with controls. While negligible staining of MHC class 2 antigens was detected on the bile duct in controls, de novo expression of MHC class 2 antigens, as well as the coexpression of HLA-DR, HLA-DQ, and HLA-DP antigens on the bile duct epithelial cells, was observed in PBC. By electron microscopy, HLA-ABC and HLA-DR antigens were present preferentially along the basolateral domain of the cell surface of the bile duct epithelial cells and on the membrane of the endoplasmic reticulum in the cytoplasm, suggesting that these MHC antigens are synthesized by the bile duct epithelial cells in PBC. The distribution of these MHC antigens on the basolateral surface of the bile duct epithelial cells, where they are easily accessible to immunocytes, supports the idea that MHC-restricted cytotoxic T lymphocytes are involved in the bile duct injury in PBC.

The sensitivity and specificity of single cell polymerase chain reaction (PCR) were studied. Its high sensitivity enabled detection of a single-copy gene, such as human T-lymphotropic virus type I genome in paraffin sections. The rate of obtaining positive signals with this method was affected by the number of copies of the gene in the target cell. Specificity was satisfactory if the procedure was properly and carefully followed. Since the single cell PCR is a time-consuming method which requires skill and experience to pick up the target cells accurately, the applicability of this method is limited. It works best when it is used to analyze a single or a few copy genes in histologically identified cells.

The accumulation of polymorphonuclear leukocytes (PMN) in synovial fluid is a common feature of rheumatoid arthritis (RA). We studied the chemotactic response of PMN obtained from the synovial fluid and from the peripheral blood of patients with RA using a modified Boyden's method, in which interleukin-8 (IL-8) or N-formyl-methionyl-leucyl-phenylalanine (FMLP) was used as a chemotactic agent. The IL-8-induced response of peripheral blood PMN from 15 patients with RA did not differ from that of 15 healthy controls. A decreased chemotactic response to IL-8 was, however, observed in PMN from the synovial fluid of 12 patients with RA compared with peripheral blood cells of the same individual. This defective chemotactic ability of PMN was inversely correlated with the number of infiltrating cells in the synovial fluid. We also obtained similar results with FMLP. These results indicate that the chemotactic ability of PMN may be reduced after migrating to the synovial fluid.

Previous investigation showed that mouse ascites sarcoma cells permeabilized with appropriate concentrations of detergents (Triton X-100, Nonidet P-40 and Brij 58) had high replicative DNA synthesis in the presence of the four deoxyribonucleoside triphosphates, ATP, Mg2+ and proper ionic environment. The present study showed the optimum detergent concentration for DNA synthesis coincided closely with the minimum detergent concentration for inducing cell swelling. Phase contrast microscopy and electron microscopy of Triton-permeabilized cells showed the characteristic swollen cytoplasms and nucleus. Autoradiographic study showed that the DNA synthesis in permeable cells was confined to the nucleus. Cell viability and [3H] deoxythymidine uptake were impaired at much lower concentrations of Triton X-100 than the optimum concentration for in vitro DNA synthesis. In Triton-permeabilized cells, the minimum Triton concentration that produced cell swelling also seemed to produce high repliative DNA synthesis, which reflects the in vivo state of DNA synthesis.

Delayed cerebral vasospams is caused by excessive accumulation of dopamine-beta-hydroxylase (DBH) and noradrenaline in cerebral vessel walls. This study demonstrates the mechanisms of delayed spasm, particularly the role of red blood cell components, and the successful relief of delayed cerebral vasospasm. Spasmogenic substances which contained a heme component, such as methemoglobin, methemalbumin and catalase enhanced DBH activity in human serum as measured by a one step chemical spectrophotometric assay. The concentration which gave the highest DBH activity caused the maximum constriction of the basilar artery, when the substances were applied topically. Among components of red cells, methemoglobin, methemalbumin, catalase and nicotinamid adenin dinucleotide (NADH) caused constriction of basilar artery in cats, when applied topically, whereas hematin, hemin and bilirubin caused no significant spasm. An oxyhemoglobin solution obtained by mixture with methemoglobin and ascorbic acid produced no significant vascular spasm either. Relief of delayed cerebral vasospasm was obtained with topical application of specific alpha adrenergic blocking drug such as phenoxybenzamine, specific inhibitors of DBH such as fusaric acid, o-phenanthroline and alphaalpha' dipyridyl beta2 adrenergic stimulants such as salbutamol, and a phosphodiesterase inhibitor, ascorbic acid.

Primary mass culture of isolated cells from adult rat livers by the trypsin-perfusion method uas carried out to investigate cytological and biochemical properties of primary cultured cells. Two main types of cells were found in the course of primary culture of isolated hepatic cells. One was a group of polygonal cells with granular cytoplasm, which appeared to arrange themselves in cords and clusters 3 to 4 days postinoculation and then gradually decreased in number. These cells seemed to be associated with expression of liver specific functions such as higher tyrosine aminotransferase levels and transient increases in albumin production. Another type of cells was relatively small in size and had clear cytoplasm, which grew out rapidly in place of the polygonal cells and proliferated also in subculture. alpha-Fetoprotein was detected in the cultured media of the proliferating clear cells. These results suggest that the polygonal cells and the clear cells may correspond to the mature hepatocytes and the hepatocytic stem cells in vivo, respectively.

The biological specificity of the endotoxin receptor on platelet membranes was examined. The binding indices of platelets in experimental endotoxemia which was induced by intravenous administration of endotoxin (Lipopolysaccharide of E. coli, Difco) to rabbits were found to be 30% of the control at 60 min after the injection. The result suggests that the endotoxin receptor of platelets was already occupied. The binding indices of human platelets were measured after pretreatment with pharmacologically active substances which were assumed to effect platelet activity. The binding of LPS to platelets showed competitive inhibition at pharmacologically effective doses, but other substances merely inhibited platelet activity. One interpretation is that there is a common receptor on platelet cell membranes for lipopolysaccharide of E. coli and endotoxin. The sensitivity to endotoxin in vivo and binding indices of platelets were examined in rabbits and guinea pigs since their response to endotoxin is almost opposite with regard to sensitivity. The binding indices of platelets from rabbits and guinea pigs showed a positive correlation with the endotoxin sensitivity. Those findings indicate that platelets play a key role in vivo in the clinical course of endotoxemia.

This research was performed to establish a cell line from experimental bladder tumor and to discuss the biological characteristics of the cell line so established. Tissue cultures of epithelial cells were derived from a rat bladder cancer induced by BBN. The cells showed loss of contact inhibition and the phenomenon of piling up after several subcultures. Colonial cloning was used. The population doubling time of the wild strain and the colonial clones was about 30 h. The chromosomal mode ranged from triploid to tetraploid to tetraploid. Plating efficiency was well below 20%. Intraperitoneal backtransplantation into newborn Wister rats resulted in tumors in all cases. These tumors, in some parts, resembled primary transitional cell carcinoma. The major tumor cell groups, however, showed marked keratinization and the picture of squamous cell carcinoma. The nucleus/cytoplasm ratio and the numbers of nuclei, free ribosomes and intracytoplasmic microfibrils were increased. Dense microvillus arrangements characterized the electron microscopic picture. During the mitotic phase, the cells became large and globular whereas the microvilli were relatively short and were gathered profusely over the whole surface. Cells in the gap 1-synthetic phase developed lamellipodia and pseudpodia-like cytoplasmic processes and were polygonal in shape. Microvilli were present in the central part containing the nucleus, but their numbers were somewhat decreased and their height increased (scanning electron microscopy).

Malignant fibrous histiocytoma of soft part is rather common but malignant fibrous histiocytoma of the bone is rarely encountered clinically. Authors present five cases of malignant fibrous histiocytoma with skeletal involvement and discuss their clinical course, x-ray findings and histological features. This tumor has marked tendency for local recurrence and metastasis. Other bone tumors such as giant cell tumor, aneurysmal bone cyst, non ossifying fibroma, osteosarcoma, fibrosarcoma of bone and metastatic cancer can be excluded by several characteristic findings observed in x-rays as well as histopathological features. All information on the patient should be carefully analysed, because it is difficult to decide whether bone involvement is primary or secondary. Four out of five cases definitely originated within the bone.

In view of comparatively-high incidence of papillary, well or moderately-well differentiated, transitional cell carcinomas in urology, and of frequent recurrence of carcinomas after appropriate procedures, we have undertaken the correlative study on urinary cytology with cystoscopy, pathology and the amount of fibrinogen and degradation products of fibrinogen and fibrin (FDP). Cytopathologically, 191 cases were confirmed histologically for cancers out of 442 cases studied cytologically; among these 442 classes IV and V were found in 136 cases, and 99 of 136 cases (72.8%) had cancers. Admittedly, we were unable to suspect tumors cytologically in 24.5% of the cases. As to histological gradings and cytology, 48.7% of classes I and II in well differentiated were found against 52.9% and 57.1% of classes IV and V in moderately-well and poorly differentiated carcinomas, respectively. Urinary FDP assay was quite promising; out of 19 cases with both positive cytology and FDP, 18 (94.7% had carcinomas histologically, whereas 12 of 56 cases (21.4%) with both negative cytology and FDP bore cancers. Subsequently, several proposals for improving the diagnostic accuracy were discussed. We concluded the importance of accumulating more cases by combining several diagnostic procedures, especially among well and moderately-well differentiated carcinomas.

Electron microscope observation of cultured human leukemic B cell, T cell and null cell lines and reverse transcriptase assay of the culture supernatants were all negative for the presence of C-type virus. Bat cell line, which propagates primate C-type viruses well, was cocultivated with the human leukemic cell lines, in the hope of amplification of virus if present. Three weeks after mixed culture, the culture supernatants were again examined for reverse transcriptase activity and the cells were tested for syncytia formation by cocultivation with rat XC, human KC and RSb cell lines. All these tests, except for the positive control using a simian sarcoma virus, were negative, suggesting that no C-type was produced from these human leukemic cell lines.

The effect of various hormones on cytological and biochemical properties of cultured hepatic cells were investigated in order to obtain long-term survival of the hepatocytes with adult liver functions in primary culture. Insulin supplementation of the culture medium enhanced the attachemnt efficiency of cells in primary culture without affecting either maintenance of morphological characters of epithelial cells or retention of liver-specific functions in cultured cells. A combination of dexamethasone and insulin was apparently effective in stimulating the formation of a monolayer of polygonal cells with granular cytoplasm and in maintenance of liver-specific functions for relatively longer periods. Supplementation with either dexamethasone or hydrocortisone alone enhanced tyrosine aminotransferase activities in cultured cells for at least 4 days postinoculation. These steroid hormones also allowed growth of small epithelial cells with clear cytoplasm and maintenance of increased albumin production for 8 days after inoculation. The roles of these hormones in the primary culture of isolated hepatic cells are discussed in the present paper.

The incidences, distribution and histopathological findings of N, N'-dimethylnitrosourea (DMNU)-induced brain microtumors in Sprague-Dawley rats were studied. Subcutaneous injections of DMNU in young adult rats one a week resulted in the induction of 122 gliomas in 38 animals with an incidence of 69% after a time lapse of between 157 and 246 days from the first injection. Of these tumors, 66 were classified as microtumors (diameter less than about 1 mm) by detailed light microscopy observation of serial sections. The microtumors were of 3 types: 55 oligodendrogliomas, 8 astrocytomas and 3 mixed gliomas. As the tumors became larger in size, anaplasia appeared, especially in the central part of the tumors. The microtumors developed randomly throughout the brain. It was concluded that, in adult rat brains, the target cells of DMNU were well differentiated glial cells which had already migrated from the matrix layer.

Binding of bacterial endotoxin to platelets, erythrocytes, lymphocytes and granulocytes was examined by using diffusion dialysis. Platelets, erythrocytes, lymphocytes and granulocytes were fractionated from normal human blood and the binding of endotoxin (LPS: Lipopolysaccharide of E. coli) to each cell fraction was measured at 4 degrees C and the binding efficiency was expressed as a binding index (%d4degreesC +/- SD). The binding index for each cell fraction was as follows; 10.2 +/- 1.6 for platelets, 1.0 +/- 0.9 for erythrocytes, 4.3 +/- 1.6 for lymphocytes and 10.0 +/- 1.5 for granulocytes (n = 11) respectively. Since a platelet possesses a small cell surface area compared with other cells, it was clear that the endotoxin bound preferentially to platelets in vitro. The binding mechanism to the platelet cell surface was suggested to be direct binding of endotoxin to the receptor on platelet cell membrane rather than through an immunologically activated mechanism.