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1.
We have reviewed our laboratory's efforts to establish continuous human renal cancer cell lines. During the 16-year period of 1972 through 1987, 498 successive attempts resulted in establishment of 63 renal cancer cell lines. Of these lines, 46 were derived from primary kidney tumors and 17 from metastatic sites (lung, brain, bone, and lymph node). Forty-three of these lines have been characterized with regard to morphology, growth kinetics, anchorage-independent growth, tumorigenicity in athymic nude mice, and expression of kidney cell surface antigens. These results were compared with data from primary short term cultures of normal kidney epithelium. The overall success rate of establishing continuous renal cancer cell lines was 12.7%. In general, no significant difference in success was noted based on whether the specimen was derived from a primary or a metastatic lesion. However, all successfully established lines were derived from tumors exhibiting clinically "aggressive" behavior. All cell lines expressed proximal tubular cell differentiation antigens. Significant morphological heterogeneity was observed among normal kidney as well as kidney cancer cell lines in vitro. No significant difference in doubling time was found between cell lines of renal cancer and passage 1 cultures of normal kidney epithelium. Twenty-one of 30 (70%) lines assayed formed clones on soft agar and 26 of 33 (79%) lines grew in athymic mice. Among the 25 lines which were assayed for both soft agar growth and tumorigenicity in nude mice, this pair of phenotypic traits were concordant in 17 lines (60%). Four lines (16%) grew on agar but not in mice, while four other lines (16%) failed to grow in agar but were tumorigenic in mice.  相似文献   
2.
Promyelocytic leukemic HL-60 cells were incubated with different fatty acids. Arachidonic acid (AA; 20:4, n-6) and eicosapentaenoic acid (EPA; 20:5, n-3) were the most potent inhibitors of proliferation in a dose- dependent way. Retinoic acid (RA) was used as a positive control. Inhibitors of cyclooxygenase and lipoxygenase or addition of antioxidants did not influence the effect of EPA or AA on cell proliferation. Increased capacity to generate superoxide anions after phorbol ester treatment and a reduced serglycin messenger RNA level in cells treated with AA or EPA indicated that these fatty acids induced differentiation in HL-60 cells similar to that induced by RA. However, down-regulation of the c-myc mRNA level, also typical for differentiation with RA in HL-60 cells, was not observed in cells incubated with AA or EPA. Flow cytometric analyses showed that in cultures incubated with AA or EPA, the proportion of cells in the G1 phase of the cell cycle increased. Similar effects were observed with RA. By flow cytometry and light scatter analyses it could be shown that AA made 8% of the cells apoptotic and 7% necrotic. The corresponding numbers were 21% and 10% for RA-treated cells, and 19% and 32% for EPA- treated cells. The present study shows that AA and EPA reduce the proliferation rate of HL-60 cells. This is mediated by mechanisms independent of eicosanoids or lipid peroxidation products and is due to effects both on apoptosis/necrosis and cell differentiation.  相似文献   
3.
4.
Immunohistologic dissection of the human kidney using monoclonal antibodies   总被引:5,自引:0,他引:5  
Nine murine monoclonal antibodies which detect differentiation antigens of the human kidney are described. Immunofluorescence and immunoperoxidase studies demonstrate that these antigens are expressed by different cell types comprising the nephron. Monoclonal antibody MA99 detects a glycoprotein complex of the glomerular basement membrane. Monoclonal antibody S4 detects a glycoprotein of 160,000 daltons (gp160) expressed by glomerular and proximal tubular epithelial cells. Monoclonal antibodies S23, S27 and S6 immunoprecipitate a glycoprotein of 120,000 daltons (gp120) found on cells of the proximal tubule and portions of Henle's loop. Monoclonal antibody C26 identifies a glycoprotein of 40,000 daltons (gp40) expressed by cells of the distal and collecting tubules. Monoclonal antibodies M2 and S8 are specific for A and B blood group antigens, respectively, found on cells of the collecting tubule in individuals of the respective blood type. This panel of antibodies is useful in the study of normal renal embryogenesis, microanatomy and physiology as well as pathological processes including tumors.  相似文献   
5.
1. The California hagfish, Eptatretus stoutii, seems to be completely lacking in adaptive immunity: it forms no detectable circulating antibody despite intensive stimulation with a range of antigens; it does not show reactivity to old tuberculin following sensitization with BCG; and gives no evidence of homograft immunity. 2. Studies on the sea lamprey, Petromyzon marinus, have been limited to the response to bacteriophage T2 and hemocyanin in small groups of spawning animals. They suggest that the lamprey may have a low degree of immunologic reactivity. 3. One holostean, the bowfin (Amia calva) and the guitarfish (Rhinobatos productus), an elasmobranch, showed a low level of primary response to phage and hemocyanin. The response is slow and antibody levels low. Both the bowfin and the guitarfish showed a vigorous secondary response to phage, but neither showed much enhancement of reactivity to hemocyanin in the secondary response. The bowfin formed precipitating antibody to hemocyanin, but the guitarfish did not. Both hemagglutinating and precipitating antibody to hemocyanin were also observed in the primary response of the black bass. 4. The bowfin was successfully sensitized to Ascaris antigen, and lesions of the delayed type developed after challenge at varying intervals following sensitization. 5. The horned shark (Heterodontus franciscii) regularly cleared hemocyanin from the circulation after both primary and secondary antigenic stimulation, and regularly formed hemagglutinating antibody, but not precipitating antibody, after both primary and secondary stimulation with this antigen. These animals regularly cleared bacteriophage from the circulation after both the primary and secondary stimulation with bacteriophage T2. Significant but small amounts of antibody were produced in a few animals in the primary response, and larger amounts in the responding animals after secondary antigenic stimulation. 6. Studies by starch gel and immunoelectrophoresis show that the hagfish has no bands with mobilities of mammalian gamma globulins; that the lamprey has a single, relatively faint band of this type; and that multiple gamma bands are characteristic of the holostean, elasmobranchs, and teleosts studied. By this method of study, the bowfin appeared to have substantial amounts of gamma2 globulin. 7. We conclude that adaptive immunity and its cellular and humoral correlates developed in the lowest vertebrates, and that a rising level of immunologic reactivity and an increasingly differentiated and complex immunologic mechanism are observed going up the phylogenetic scale from the hagfish, to the lamprey, to the elasmobranchs, to the holosteans, and finally the teleosts.  相似文献   
6.
Expression of blood group-related carbohydrate antigens was examined in frozen sections from a series of ovarian carcinomas of different histological types using an indirect immunoperoxidase technique. Antigenic specificities belonging to the O(H) and Lewis blood group families (H-1, H-2, Le(a), sLe(a), Le(x), sLe(x), Le(b) and Le(y)) or the mucin-core family (Tn, sTn and TF) were studied. A distinct difference in antigen expression between mucinous and other ovarian carcinomas (serous and endometrioid) was observed. Specifically, mucinous tumors tended to express sTn, Le(a) and sLe(a) strongly and homogeneously, whereas serous and endometrioid tumors rarely expressed these specificities and, in contrast, expressed Le(y) and H type 2 antigen strongly. When expressed in serous tumors, sTn was usually distributed in a heterogeneous pattern, whereas sTn expression in mucinous tumors was much more homogeneous. The distribution of Le(y) in serous tumors was noticeably homogeneous. H-1, Le(x), sLe(x), Le(b), TF and Tn specificities were rarely expressed in any type of ovarian carcinoma. Our results provide further support for the different histogenesis of mucinous and non-mucinous tumors and indicate alternative differentiation pathways for the 3 pathological subtypes of ovarian tumor. They also provide the basis for the choice of carbohydrate antigens for active and passive immunotherapy of ovarian carcinomas.  相似文献   
7.
Atlantic salmon (Salmo salar) were exposed for 36 days to water from the acidified (pH 5.2) Fossbekk River (Norway) with 50 micro x L(-1) of aluminium (Al) added as AlCl(3), or to circumneutral water (pH 6.6) from Ims River (Norway). Food consumption, cardiac output, swimming activity, and growth rate were measured to determine the effects of sublethal levels of Al in acidic water on the bioenergetics of the fish. Food consumption was reduced in acidic water and Al during the first 12 days, but was not significantly different from the control group during the rest of the exposure. A significant decrease in body weight was concomitant with the reduction in food consumption. The fish also kept losing weight during the rest of the exposure despite the return of their appetite to normal. Cardiac output of the fish exposed to acidic water and Al was not significantly different from the control group after 36 days of exposure. Swimming activity remained significantly elevated throughout the exposure to acidic water and Al. These results indicate that sublethal levels of Al can alter the energy budget of Atlantic salmon living in acidified surface waters.  相似文献   
8.
A purified cobra venom factor with C-inhibiting activity also promotes lysis of erythrocytes in fresh mammalian serum. Lysis-inducing activity of purified cobra venom factor was found in sera of lower vertebrates including the cyclostome hagfish and in invertebrates. Lysis-inducing activity was most effective with frog serum. Frog serum was found to be more hemolytic for Es in the presence of CVF than when cells were sensitized with hemolysin. The hemolysis induced by CVF with frog serum, as in the higher vertebrates, was inhibited when sera were pretreated with known C inhibitors including heat, chelators, endotoxin, immune complexes, and CVF itself. Complexes formed with CVF and either frog serum or invertebrate hemolymph promoted lysis of indicator cells in the presence of frog serum in EDTA. This lysis was most marked when the starfish-CVF complex was used and was C-dependent. Conversely, complex formed with frog serum and CVF promoted lysis of E in the presence of invertebrate hemolymph (Limulus) in EDTA. Hence, serum components were to some degree at least interchangeable between vertebrate sera and invertebrate hemolymph. Lysis-inducing activity of purified CVF occurs in a wide range of species, has revealed activities resembling those of terminal C-components in lower vertebrates and invertebrates, and provides one means for study of C and C-like activities in primitive species.  相似文献   
9.
BACKGROUND: Elevated plasma concentration of homocysteine is an independent risk factor for development of cardiovascular diseases. MATERIALS AND METHODS: We evaluated potential links between homocysteine and atherothrombogenesis by relating the plasma concentration of homocysteine to (i) dietary antioxidants and omega-3 fatty acids (and determined influence of intervention with antioxidants or omega-3 fatty acids); (ii) markers of endothelial cell function; and (iii) peripheral blood mononuclear cell mRNA levels. RESULTS: We observed an inverse relationship between the plasma homocysteine concentration and dietary intake of vegetables, vitamin C and beta-carotene and between homocysteine and the serum concentration of folate, vitamin B12 and omega-3 fatty acids. Intervention with antioxidants or omega-3 fatty acids did not affect plasma homocysteine concentration. The plasma levels of cysteinylglycine and vitamin B12 correlated positively with circulating E-selectin and VCAM-1, respectively, whereas folate in serum and blood correlated negatively with P-selectin. A negative correlation was found between the concentrations of homocysteine and von Willebrand factor. Negative and positive correlations were found between plasma homocysteine and the mononuclear cell mRNA levels of peroxisome proliferator activated receptor delta (PPAR delta) and c-myc respectively. A negative correlation was also found between plasma homocysteine and mononuclear cell mRNA levels of the proteoglycan serglycin. Homocysteine was not correlated with serum activity of glutathione peroxidase or with the mRNA level of glutathione peroxidase in mononuclear cells. CONCLUSION: The plasma homocysteine level was negatively correlated with dietary intake of vegetables, including vitamins C and E, and serum omega-3 fatty acids, whereas supplementation with antioxidants or omega-3 fatty acids did not affect plasma homocysteine concentration. Homocysteine was not associated with circulating adhesion molecules or increased procoagulant activity, but homocysteine may alter mononuclear cell gene expression. Cysteine showed no significant correlation with these parameters.  相似文献   
10.
In many parts of the world contact with infected livestock may involve a serious risk of the spread of human brucellosis. Partial control of bovine brucellosis has been achieved by slaughter of infected herds and immunization of cattle with Brucella abortus strain 19 living vaccine. However, in areas where such measures are unpractical there remains a need for protection of humans. This study compares the safety of two living Brucella vaccine preparations in human volunteers.  相似文献   
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