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1.
Ido Simon 《生物化学与生物物理学报:生物膜》1979,556(3):408-422
The fatty acid composition and some physical properties of intact cells and isolated plasma membranes of two types of mouse myeloid leukemia cell clone grown in culture have been examined. One clone type, MGI+D+, can be induced by the macrophage and granulocyte-inducing protein (MGI) to differentiate into mature macrophages and granulocytes. The other clone type, MGI+D?, could not be induced to differentiate into mature cells. A two-fold increase in the ratio of saturated fatty acid to unsaturated fatty acid was found in the MGI+D? compared to the MGI+D+ clones. The MGI+D? clones produced an unusual polyunsaturated C20:5 fatty acid at 28°C, whereas the MGI+D+ clones did not grow at this temperature. The cells and their isolated plasma membranes were studied by electron spin resonance. The motion of the 5-nitroxide stearate spin label was found to be higher in the intact cells and in the membranes of MGI+D? clones than of the MGI+D+ clones. The cells of MGI+D+ clones showed a similar freedom of motion to normal myeloblasts from the bone marrow. The results indicate that myeloid leukemia cells which differ in their competence to be induced to differentiate into mature cells have different physical properties of their plasma membranes and that this is correlated with their fatty acid acyl chain composition. 相似文献
2.
The hydrolysis of ATP and AMP by enzymes located on the external side of the plasma membrane (ecto-ATPase and ecto-AMPase) was studied in mouse myeloid leukemic cells, normal early myeloid cells, and normal mature granulocytes and macrophages. Nine clones of myeloid leukemic cells were used belonging to three groups that differ in their ability to be induced to differentiate by the differentiation-inducing protein MGI. These three groups consisted of MGI+D+ that can be induced to undergo complete differentiation, MGI+D- that can be induced to partially differentiate and MGI-D- with no induction of differentiation. The ecto-ATPase activity of normal early myeloid cells was similar to that of normal mature granulocytes and macrophages and higher than that of any of the leukemic cells. Among the leukemic cells, the MGI-D- cells had the highest level of ecto-ATPase activity. The behaviour of ecto-AMPase differed from that of ecto-ATPase. Some MGI-D- clones had a higher ecto-AMPase activity than normal cells and MGI+D- and MGI+D+ cells showed no detectable activity. Neither the ecto-ATP-ase nor ecto-AMPase activities changed after induction of differentiation in normal early myeloid or MGI+D+ leukemic cells. The results indicate that the myeloid leukemic cells had a decreased ability to hydrolyse external ATP, that there can be an independent regulation of ecto-ATPase and ecto-AMPase and that neither of these enzyme activities changed during differentiation. 相似文献
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4.
There are clones of myeloid leukemic cells that can be induced to differentiate by the normal differentiation-inducing protein MGI to form Fc and C3 rosettes, mature macrophages and granulocytes. One of these clones (MGI+DMSO+) was also inducible by dimethylsulfoxide (DMSO) for C3 but not Fc rosettes, and for mature macrophages but not for mature granulocytes. Other clones (MGI+DMSO-) were inducible by MGI but not DMSO and a third type of clone (MGI-DMSO-) was not inducible by either compound. Clones that differed in their inducibility by DMSO showed a similar inhibition of cell multiplication by DMSO. The results indicate, that some stages of differentiation can be induced by DMSO in an appropriate clone of myeloid leukemic cells and that there are different cellular sites for induction by DMSO and MGI. 相似文献
5.
Regulation of actin and other proteins in the differentiation of myeloid leukemic cells. 总被引:11,自引:0,他引:11
The regulation of cytoplasmic proteins in mutants of mouse myeloid leukemic cells, differing in their competence to be induced to differentiate by the normal macrophage- and granulocyte-inducing protein (MGI) and the steroid inducer dexamethasone, was analyzed using SDS-polyacrylamide gel electrophoresis of 35S-methionine-labeled proteins. Before induction, no consistent differences in the pattern of cytoplasmic proteins were found between clones with different capabilities to differentiate.Four MGI+D+ clones, which are induced by MGI for Fc and C3 rosettes, the synthesis and secretion of lysozyme, and the formation of mature macrophages and granulocytes, all showed the same nine prominent changes in cytoplasmic proteins after induction. Five of these changes were either an increase or a decrease in proteins present in uninduced cells; four proteins appeared to be newly synthesized. One of the proteins that increased after induction was identified as actin. The pattern of cytoplasmic proteins from MGI-induced MGI+D+ clones more closely resembled that of normal peritoneal macrophages and granulocytes than the pattern of the uninduced clones. The relationship of these protein changes to cell differentiation was further substantiated by the finding that MGI+D? cells, which can be induced by MGI for Fc and C3 rosettes and lysozyme, but not for mature cells, showed only four cytoplasmic protein changes which were quantitatively less than those found for MGI+D+ clones. An MGI?D? clone which was not inducible for any differentiation-associated properties by MGI showed no alteration in protein synthesis. Thus in all the clones studied, there was a correlation between the number and extent of protein changes and the degree of MGI-induced differentiation.In MGI+D+ clones, some of the differentiation-associated properties induced by MGI can be induced by the steroid hormone dexamethasone. Of the nine protein changes induced by MGI, six were also induced by dexamethasone, and no changes were induced by dexamethasone which were not also induced by MGI. These results, which were also shown by two-dimensional polyacrylamide gel electrophoresis, indicate that in cells which can respond to both MGI and dexamethasone, the proteins induced by dexamethasone were a subset of those induced by MGI. 相似文献
6.
The regulation of gene expression in leukemic and normal myeloblasts induced to differentiate by the normal macrophage and granulocyte inducing protein MGI was studied by analysis of protein changes using two-dimensional polyacrylamide gel electrophoresis. During the 6-day period of differentiation from myeloblasts to mature cells, there was a programmed sequential change in the rate of synthesis of 217 of the 450 proteins detected in a MGI+D+ leukemic clone. The developmental program was initiated with a decrease in the synthesis of many proteins within the first hour, whereas the synthesis of new proteins occurred later, mostly between the second and fourth days. The mature cells showed a specialization associated with a changeover and increased synthesis of the major protein species. Both the MGI+D+ leukemic and the normal myeloblasts showed a similar sequence of protein changes during differentiation. The normal developmental program was thus maintained in the MGI+D+ leukemic cells. Cell mutants which differ in their competence to be induced to differentiate by MGI were used to dissect the developmental program of differentiation. Sixty-six protein changes were induced by MGI in partially differentiatable MGI+D? clones, whereas only 12 or 16 protein changes were induced in different MGI?D? clones which had not been induced for any previously known differentiation-associated property. In these mutant clone types, the induced protein changes were subsets of those induced by MGI in the MGI+D+ leukemic and normal myeloblasts. These subsets spanned the whole 6-day period of differentiation and had the same developmental sequence as in the fully differentiatable MGI+D+ cells. These data indicate that the protein changes during differentiation are not organized as one sequence, but rather as multiple, parallel sequences which can be separately induced. MGI induced some, but not all, of these sequences in the mutant clones. It is concluded that differentiation consists of multiple, parallel, separately programmed pathways of gene expression. Analysis of the initial differences between the proteins synthesized in untreated normal and leukemic myeloblasts has shown that all the leukemic clones, when compared to normal myeloblasts, constitutively expressed the MGI-induced state for a common subset of 14 proteins. In addition, the MGI+D? and MGI?D? clones, compared to MGI+D+, constitutively expressed the differentiated state for other subsets of proteins. The size of these constitutively expressed subsets was larger in MGI?D? than in MGI+D? clones. It is, therefore, suggested that the constitutive expression of some pathways of gene expression results in leukemia, whereas the constitutive expression of other pathways results in a decreased competence for the induction of differentiation. 相似文献
7.
Genetically differerent clones of myeloid leukemic cells have been used to study the activation of normal genes in these malignant cells by the normal physiological inducer of myeloid cell differentiation, the protein MGI. In appropriate clones, MGI induced the normal differentiation-associated property of chemotaxis to a variety of compounds including the steroid hormone dexamethasone. The induced cells could also distinguish among different steroids by chemotaxis, suggesting that there are specific membrane interaction sites for steroids. The sequence of differentiation in these cells was the formation of C3 and Fc rosettes leads to phagocytosis of these rosettes and chemotaxis leads to synthesis and secretion of lysozyme leads to mature macrophages or granulocytes. The use of appropriate mutants and the comparison of induction by MGI and dexamethasone has shown that chemotaxis to casein can be dissociated from: chemotaxis to dexamethasone, ATP, and bacterial factor; formation of C3 or Fc rosettes; phagocytosis of these rosettes; synthesis of lysozyme; and the formation of mature cells. It is suggested from this dissection of normal differentiation that there are different membrane changes for specific chemotaxis, formation of these rosettes, and their phagocytosis, and that induction of each of these properties requires activation of different genes. 相似文献
8.
Normal hematopoietic cells require the presence of a protein (MGI) in the appropriate conditioned medium (CM) for cell viability and growth and for differentiation to mature macrophages and granulocytes. Clones of myeloid leukemic cells have been established in culture (D+ clones) which require CM with this protein for differentiation, but not for cell viability and growth. It has been shown that these leukemic cells can be induced by CM to again require, like normal cells, the presence of CM for cell viability and growth. Induction of this requirement, which will be referred to as RVG, occurred before the D+ cells differentiated to mature granulocytes. Clones of myeloid leukemic cells (D? clones) that could not be induced to differentiate to mature cells, did not show the induction of RVG. The steroid hormones prednisolone and dexamethasone can induce some, but not all the changes associated with differentiation of D+ cells. Incubation with these steroids did not result in the induction of a requirement for these steroids for cell growth and viability. Studies with CM from different sources have shown, that all batches that induced RVG also induced differentiation of D+ cells and that both activities were inhibited after treating the CM with trypsin. It is suggested that the same protein (MGI) may be involved in both activities. Incubation of D+ cells with CM resulted in an increase in agglutinability by concanavalin A and this increase was maintained even in the absence of CM. This suggests, that the induction of RVG in D+ myeloid leukemic cells is associated with a change in the cell surface membrane. 相似文献
9.
An enriched population of early myeloid cells has been obtained from normal mouse bone marrow by injection of mice with sodium caseinate and the removal of cells with C3 (EAC) rosettes by Ficoll-Hypaque density centrifugation. This enriched population had no EAC or Fc (EA) rosettes and contained 87% early myeloid cells stained for myeloperoxidase and/or AS-D-chloroacetate esterase, 7% cells in later stages (ring forms) of myeloid differentiation and 6% unstained cells, 2% of which were small lymphocytes. After seeding in agar with the macrophage and granulocyte inducer MGI, the enriched population showed a cloning efficiency of 14% when removed from the animal and of 24% after one day in mass culture. Both the enriched and the unfractionated bone marrow cells gave the same proportion of macrophage and granulocyte colonies. The normal early myeloid cells were induced to differentiate by MGI in mass culture in liquid medium to mature granulocytes and macrophages. The sequence of granulocyte differentiation was the formation of EA and EAC rosettes followed by the synthesis and secretion of lysozyme and morphological differentiation to mature cells. D+ myeloid leukemic cells with no EA or EAC rosettes had a similar morphology to normal early myeloid cells and showed the same sequence of differentiation. The induction of EA and EAC rosettes occurred at the same time in both the normal and D+ leukemic cells, but lysozyme synthesis and the formation of mature granulocytes was induced later in the leukemic than in the normal cells. The results indicate that selection for non-rosette-forming normal early myeloid cells also selected for myeloid colony forming cells, that these normal early myeloid cells can form colonies with differentiation to macrophages and granulocytes, that normal and D+ myeloid leukemic cells have a similar sequence of differentiation and that the normal cells had a greater sensitivity for the formation of mature cells by MGI. 相似文献
10.
D+ but not D- myeloid leukemic cells can be induced by the appropriate conditioned medium or by serum from endotoxin treated mice, to undergo cell migration in agar, cell attachment to the surface of a Petri dish and differentiation to mature macrophages and granulocytes. Inhibition of cell multiplication by cytosine arabinoside, hydroxyurea, mitomycin C, thymidine, 5-bromodeoxyuridine, 5-iododeoxyuridine, 5-fluorodeoxyuridine or actinomycin D, but not by vinblastine or cycloheximide, induced cell migration, cell attachment to the Petri dish and the formation of macrophages in D+ cells. There was no induction of cell migration or formation of macrophages and a much lower induction of cell attachment in D- cells. The induction of these changes in D+ cells required protein synthesis and the inhibitors showed the same toxicity for D+ and D- cells. The results indicate, that the inhibitors induced specific surface membrane changes in D+ but not in D- cells. 相似文献
11.
Autoinduction of differentiation in myeloid leukemic cells: restoration of normal coupling between growth and differentiation in leukemic cells that constitutively produce their own growth-inducing protein. 总被引:2,自引:2,他引:0
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Growth and differentiation of normal myeloid haematopoietic cells are regulated by a family of macrophage- and granulocyte-inducing (MGI) proteins. Some of these proteins (MGI-1) induce cell growth and others (MGI-2) induce cell differentiation. Addition of MGI-1 to normal myeloid cells induces growth and also induces the endogenous production of MGI-2. This induction of differentiation-inducing protein by growth-inducing protein then ensures the coupling between growth and differentiation found in normal cells. There are myeloid leukemic cells that constitutively produce their own MGI-1, but the cells do not differentiate in culture medium containing horse or calf serum. By removing serum from the medium, or in medium with mouse or rat serum, these leukemic cells are induced to differentiate to mature cells, which like normal mature cells, then no longer multiply. Leukemic cells with constitutive production of MGI-1 continuously cultured in serum-free medium with transferrin were also induced to differentiate by removing transferrin. This induction of differentiation was in all these cases associated with the endogenous production of MGI-2 by the cells. The results indicate that changes in specific constituents of the culture medium can result in autoinduction of differentiation in these leukemic cells due to restoration of the induction of MGI-2 by MGI-1, which then restores the normal coupling of growth and differentiation. 相似文献
12.
Regulation of cell surface receptors for different hematopoietic growth factors on myeloid leukemic cells. 总被引:2,自引:0,他引:2
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There are clones of myeloid leukemic cells which are different from normal myeloid cells in that they have become independent of hematopoietic growth factor for cell viability and growth. The ability of these clones to bind three types of hematopoietic growth factors (MGI-1GM = GM-CSF, IL-3 = multi-CSF and MGI-1M = M-CSF = CSF-1) was measured using the method of quantitative absorption at 1 degree C and low pH elution of cell-bound biological activity. Results of binding to normal myeloid and lymphoid cells were similar to those obtained by radioreceptor assays. The results indicate that the number of receptors on different clones of these leukemic cells varied from 0 to 1,300 per cell. The receptors have a high binding affinity. Receptors for different growth factors can be independently expressed in different clones. There was no relationship between expression of receptors for these growth factors and the phenotype of the leukemic cells regarding their ability to be induced to differentiate. The number of receptors on the leukemic cells was lower than on normal mature macrophages. Myeloid leukemic cells induced to differentiate by normal myeloid cell differentiation factor MGI-2 (= DF), or by low doses of actinomycin D or cytosine arabinoside, showed an up-regulation of the number of MGI-1GM and IL-3 receptors. Induction of differentiation of leukemic cells by MGI-2 also induced production and secretion of the growth factor MGI-1GM, and this induced MGI-1GM saturated the up-regulated MGI-1GM receptors. It is suggested that up-regulation of these receptors during differentiation is required for the functioning of differentiated cells. 相似文献
13.
Abnormal expression of homeobox genes is one of the abnormalities associated with the development of murine and human leukemia. Myeloid leukemic cells that can be induced to differentiate to mature cells by interleukin 6 were stably transfected with an activated Hox-2.4 homeobox gene. Expression of the Hox-2.4 gene in the transfected clones inhibited specific pathways of the myeloid differentiation program induced by interleukin 6. The expression of some genes associated with differentiation was almost completely blocked, and the expression of other genes was either partially inhibited or not affected. The results support the hypothesis that abnormal expression of Hox-2.4 may contribute to the development of leukemia by interfering with the differentiation program. 相似文献
14.
G Oshima M Yamada T Sugimura 《Biochemical and biophysical research communications》1979,90(1):158-163
The protease activities of mouse myeloid leukemia cells Ml were examined using fluorescein isothiocyanate-labeled albumin as substrate. Protease activity in Ml cells was greatest at alkaline pH values with a maximum at pH 11.0, and only slight activity was seen at neutral and acidic pHs. When Ml cells were induced to differentiate into mature cells by lipopolysaccharide, their alkaline protease activity decreased greatly with marked increase in acid protease activity. Moreover, in a variant cell line Mml with the properties of differentiated Ml cells, no protease activity was found at alkaline pH values. 相似文献
15.
Dissection of the immediate early response of myeloid leukemia cells to terminal differentiation and growth inhibitory stimuli 总被引:8,自引:0,他引:8
K A Lord A Abdollahi B Hoffman-Liebermann D A Liebermann 《Cell growth & differentiation》1990,1(12):637-645
To better understand the immediate early genetic response of myeloid cells to terminal differentiation and growth inhibitory stimuli, complementary DNA clones of myeloid differentiation primary response (MyD) genes have recently been isolated. In this study, a set of known (junB, c-jun, ICAM-1, H1(0), and H3.3 histone variants) and novel (MyD88, MyD116) MyD genes were used as immediate early molecular markers to further dissect the primary genetic response of myeloid cells to various differentiation and growth inhibitory stimuli. Expression of all of these MyD genes was highly induced in autonomously replicating differentiation inducible M1D+ myeloblasts following induction of terminal differentiation and growth inhibition by interleukin 6. Expression of all MyD genes except MyD88 was induced upon inhibition of M1D+ cell growth and induction of early, but not late, differentiation markers by interleukin 1 and lipopolysaccharide. In sharp contrast, only expression of H1(0) and H3.3 histone variants was increased following inhibition of M1D+ cell growth by interferon beta or gamma, which did not induce any differentiation associated properties. No increase in the expression of any of these MyD genes was seen in a clone of WEHI-3B D- myelomonocytic cells following stimulation with interleukin 6, which neither induced it for differentiation nor inhibited its growth. 12-O-Tetradecanoylphorbol-13-acetate, known to be a potent inducer of jun expression in many cell types, failed to induce high or stable expression of junB and c-jun in M1D+ cells, where it did not induce differentiation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
16.
The individual phospholipid concentrations, and their respective fatty acid distributions, in whole platelet lysates and plasma membranes derived from unstimulated and thrombin-stimulated intact human platelets were studied. This was of interest, since previous work had led to the suggestion that altered phospholipid concentrations in plasma membranes of intact stimulated cells may be of importance in mediating cellular responses. The concentrations (nmol/mg protein) of phosphatidylinositol in whole platelet lysates and plasma membranes derived from thrombin-activated platelets decreased by 37 and 45%, respectively, a compared to their corresponding controls. As well, concentrations of plasma membrane phosphatidylcholine and phosphatidylethanolamine in thrombin-stimulated platelets decreased by 20 and 9%, respectively, when compared with their control values. The amounts of phosphatidylserine and sphingomyelin in whole platelet lysates and plasma membranes were unchanged by exposure to thrombin. Fatty acid analyses revealed that thrombin stimulation of intact human platelets induced a decrease in the arachidonate content (from 37.7 to 33.1 wt.% of total fatty acid) of plasma membrane phosphatidylinositol. Similar shifts in the wt% of arachidonic acid in plasma membrane phosphatidylcholine were found. These results indicate that thrombin stimulation of intact human platelets produces a significant decrease in the mass of phosphatidylinositol in plasma membranes and raises the suggestion that the preferential depletion of the plasma membrane in arachidonoyl-containing phosphatidylinositol may be of importance in mediating cellular responses to external stimuli. 相似文献
17.
Dictyostelium discoideum grown axenically in media containing polyunsaturated fatty acids exhibited normal growth rates but impaired differentiation (Weeks, G. (1976) Biochim. Biophys. Acta 450, 21--32). Since cell-cell contact is vital for differentiation but unnecessary for growth we have examined the isolated plasma membranes of these cells. The lipids of the plasma membranes of cells grown in the presence of polyunsaturated fatty acids contain considerable quantities of these acids, but the total phospholipid and sterol contents of the plasma membrane are close to normal. Electron spin resonance studies using 5-doxyl-stearic acid as the spin probe reveal two things. Firstly, there are no detectable characteristic transition temperatures in the plasma membranes of D. discoideum. Secondly, the plasma membranes of cell grown in the presence of polyunsaturated fatty acids have essentially the same fluidity as that of the control cells. The possible significance of this result to impaired cell-cell interaction is discussed. 相似文献
18.
P D Hodgkin L C Yamashita B Seymour R L Coffman M R Kehry 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(11):3696-3702
Plasma membranes from the mitogen-activated mouse Th2 cell clone D10.G4.1 have recently been shown to provide the cell contact-dependent signals necessary for the induction of small B cell proliferation. Together with the Th2-derived lymphokines IL-4 and IL-5, these membranes stimulate production of Ig isotypes identical to those produced when B cells were stimulated by intact Th2 cells. In contrast, Th1 clones are poor inducers of Ig production in vitro. This could be solely due to differences in the lymphokines released by Th1 and Th2 cells or to differences in the cell-cell contact signals delivered by activated Th1 and Th2 cells. We report that membranes from three different activated Th1 clones induced strong Ag-independent proliferation of small dense B cells. The level of B cell proliferation was enhanced approximately fourfold by the addition of lymphokine-containing supernatant from Con A-activated Th2 cells and was unaffected by any of the lymphokine-containing supernatants from Con A-activated Th1 clones. As with D10.G4.1 membranes, Th1 membranes alone induced B cell proliferation but not secretion of Ig. However, addition of supernatant from Con A-activated D10.G41 cells, but not any supernatants from Con A-activated Th1 cells, induced Ig secretion of all isotypes. These effects were shown to not simply result from increased B cell numbers after stimulation with Th2 lymphokines. Thus, Th1 cell clones seem to poorly induce antibody responses entirely because of their lymphokine repertoire and not because of differences or deficiencies in the ability of these cells to deliver cell contact-dependent signals to B cells. 相似文献
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20.
Wm. G. Struve R. M. Arneson J. E. Chenevey Ch. K. Cartwright 《Experimental cell research》1977,109(2):381-387
Gas chromatography and spin labeling were used to estimate the composition and fluidity of the lipid acyl chains in intact cell membranes of mouse C1300 neuroblastoma. Neurite formation and an increase in the specific activity of acetylcholinesterase are induced in this cell line by the removal of serum from the culture medium for one day prior to harvesting the cells. The fatty acid composition of induced cells was not significantly different from that of the non-induced controls. Each of the three fatty acid spin labels used in this study indicate that the membranes of induced cells are slightly more fluid than the membranes of control cells. This difference in fluidity appears to be a result of a reduction in the progressive decrease in fluidity occurring during growth in serum. A four-fold reduction in cell viability had no effect on the measured bilayer fluidity. Thus the changes in fluidity appear to be due to the presence or absence of serum rather than to cell type, age, or viability. 相似文献