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M V Berridge

Publications and source records attributed to M V Berridge.

At least 55 records · Page 3Linked to original sources
PubMed1984

Changes in cell surface antigens during stem cell ontogeny.

A panel of monoclonal antibodies that bind to the murine pluripotential stem cell CFU-s was used to examine the antigenic profile of the stem cell during ontogeny. The results show that the stem cell surface changes dramatically during development. One group of three independently derived monoclonal antibodies binds to subpopulations (50%-70%) of stem cells at plateau values, and these populations increase marginally during development. A second group of four monoclonal antibodies, including anti-H-2Kk (11-4.1), define stem cell antigens that increase from low levels in the fetal liver to high levels in adult bone marrow. The presence of these two classes of antigens on adult splenic stem cells was in general similar to that observed on adult bone marrow. Antigens defined by the first group of monoclonal antibodies were present in similar amounts on CBA, C57B1/6, and Balb/c bone marrow stem cells, whereas antigens of the second group showed mouse strain variations. Quantitative absorption analysis was used to distinguish H-2Kk (11-4.1) from 9F6, which showed a similar developmental profile. Monoclonal antibodies recognizing subpopulations of stem cells were shown to be distinct by complementation studies and recognized antigens not present on brain tissue.

Animals↗
PubMed1984

Expression of antigens of the 'T200' family of glycoproteins on hemopoietic stem cells: evidence that thymocyte cell lineage antigens are represented on 'T200'.

A panel of monoclonal antibodies has been used to investigate the presence of antigens of the 'T200' family of cell surface glycoproteins on hemopoietic stem cells. As measured by spleen colony inhibition using CBA bone marrow, stem cells were shown to be antigenically heterogeneous with respect to 'T200' family antigens; greater than 60% loss of spleen colonies was observed with 74/8 and 30F11 monoclonal antibodies and with Ly5.1 alloantiserum, whereas little effect was observed with 30G12. Two of four monoclonal antibodies with specificity for B220 showed significant inhibition of spleen colony formation. Monoclonal antibodies against Mac-1, another family of cell surface glycoproteins, had little effect on stem cells. In general, a similar pattern of spleen colony inhibition was observed in CBA, BALB/c, and C57/BL/6 mice. Spleen colony inhibition did not correlate with antibody isotype or with antibody binding to thymocytes, B lymphocytes, macrophages, or platelets as determined by indirect radioimmunoassay. Cell lineage antigens held in common between thymocytes and stem cells were shown to be wholly represented on the T200 glycoprotein. Thus, the anti-stem cell activity in anti-thymocyte serum (ATS) was absorbed by BW5147 T200+ cells but not by a T200- variant. The results show that some antigens of the 'T200' family of cell surface glycoproteins defined with monoclonal antibodies are expressed on stem cells and that other T200 antigens represented in ATS but not as yet identified with monoclonal antibodies show T lineage restriction.

Animals↗
PubMed1984

Binding of monoclonal antibodies that inhibit spleen colony formation to leukemic cell lines.

Clonogenic tumor cells and normal stem cells share the property of extensive proliferative potential. Normal stem cells are under stringent growth restraint and respond to appropriate differentiation signals, whereas tumor stem cells have lost the ability to respond normally to these controls. In an attempt to define cell surface molecules involved in the control of hemopoietic cell proliferation and differentiation, we have produced 5 monoclonal antibodies against antigens held in common between hemopoietic stem cells and the Abelson virus-induced pre-B-lymphoma cells from which they were derived. Four of these monoclonal antibodies produced greater than 90% reduction of spleen colony-forming cells, whereas the other bound to a subpopulation (60 to 70%) of spleen colony-forming cells at plateau values. The expression of antigens recognized by these and two other anti-stem cell monoclonal antibodies has been shown to correlate with the differentiation status of a panel of tumor cell lines, with greater expression being observed on cells more closely resembling the pluripotent stem cell than mature hemopoietic cells. Immunoperoxidase staining of bone marrow showed that these antigens are mainly expressed by monocytes and blast cells. Treatment of bone marrow cells with those antibodies which extensively inhibited spleen colony formation and with rabbit complement abolished the ability of progenitor cells to form colonies in soft agar. Quantitative absorption studies distinguished the antigens recognized by two of the anti-stem cell monoclonal antibodies from those detected by anti-H-2k 11-4.1 monoclonal antibody. These observations suggest that the antigens involved may play a role in the regulation of growth and differentiation of stem cells and undifferentiated leukemic cells.

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PubMed1983

Surface antigens of murine hemopoietic stem cells. VIII. Antisera define lineage antigens held in common between granulocyte-macrophage cells and between lymphoid cells.

The cell-lineage model of hemopoietic cell differentiation has been further investigated by detailed absorption analysis of the anti-stem cell activity in rabbit antisera against mouse hemopoietic cells. Of seven differentiated hematopoietic cells tested, platelets alone absorbed the anti-stem cell activity in anti-platelet serum. Thymocytes and B-lymphocytes absorbed all of the anti-stem cell activity in antithymocyte serum whereas other nonlymphocytic cells showed only partial absorbing ability. Macrophages and granulocytic cells absorbed most of the anti-stem cell activity in antimacrophage serum and antineutrophil serum whereas other cell types showed little or no absorbing capacity. Antisera against a cloned mast cell precursor line showed partial cell lineage activity whereas anti-sera against eosinophils and B-lymphocytes showed no evidence of cell lineage activity. A detailed model of cell lineage antigens on hemopoietic cells is presented.

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PubMed1982

Is Percoll innocuous to cells?

Peritoneal macrophages from mice, isolated rat liver Kupffer cells and rat testis Leydig cells ingested large numbers of Percoll particles, a gradient medium widely used for separation of cells and subcellular organelles by density-gradient centrifugation. A decrease in the percentage of macrophages adhering to plastic also occurred after exposure of the cells to Percoll, even at 4 degrees C, a temperature at which Percoll was not ingested. The effect of Percoll on macrophage adherence may involve a loose association between the density medium and the cell surface. Other cell-surface-related phenomena may also be affected by prior exposure of cells to Percoll.

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PubMed1982

Monoclonal antibodies detect subpopulations of bone marrow stem cells.

Hybridomas secreting monoclonal antibodies cross-reacting with the mouse bone marrow stem cell (CFUs) have been derived from rats immunized with mouse thymocytes and platelets, cells which have been shown to exhibit antigenic lineage relationships with the stem cell. Anti-stem cell activity in hybridoma supernatants occurs at low frequency. Of 418 hybridomas screened, 6 showed initial positivity while two yielded stable cloned cell lines. Both of these monoclonal antibodies, 1C10 and 13C6, bind to subpopulations of stem cells in the bone marrow resulting in 50-65% inhibition of spleen colony formation in lethally irradiated mice. Protein-A binding studies showed the antibodies to be rat IgG. Quantitative absorption and indirect binding studies suggest that the antigens recognized by 1C10 and 13C6 monoclonal antibodies are minor components of the inoculating cell membrane. 1C10 and 13C6 bind to minor subpopulations of cells in the bone marrow, 13 and 5% of cells being rosetted, respectively, at plateau values. These results indicate that, used in conjunction with other monoclonal antibodies or selection tecniques, these antibodies may be useful in stem cell purification.

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PubMed1982

Surface antigens of murine hemopoietic stem cells. IV. Characteristics of antisera exhibiting cell-lineage specificity, and differentiating ability of stem cells surviving treatment with antisera against cell-lineage antigens.

Hemopoietic stem cells express cell-lineage antigens in common with platelets, thymocytes and macrophages. Further evidence for the cell-lineage antigen model is presented. Erythrocyte-absorbed antiserum against purified mouse neutrophils cross-reacts with the hemopoietic stem cell in a lineage-specific manner. Thus, most of the anti-stem cell activity is absorbed out with neutrophils but not by other non-granulocytic hemopoietic cells. Of the four antisera tested for anti-stem cell activity, antiplatelet serum showed the highest degree of cell-lineage specificity (96% of the anti-stem cell activity satisfied cell-lineage criteria). To test predictions of the cell-lineage model of hemopoietic cell differentiation concerning the differentiating potential of stem cells selected for low concentration of cell-lineage antigen, bone marrow cells were treated with antiplatelet serum at a predetermined concentration required to produce 75-85% loss of spleen colonies. Stem cells surviving this treatment showed normal ability to form megakaryocytes and platelets. The results are consistent with postulates of the cell-lineage model.

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PubMed1979

A new class of cell surface antigens. Quantitative absorption studies defining cell-lineage-specific antigens on hemopoietic cells.

A new class of cell surface antigens are described which are expressed on cells within a particular differentiation pathway. These antigens, termed cell-lineage-specific antigens, are shown to be distinct from differentiation antigens and from histocompatibility antigens. The presence of these antigens was demonstrated by raising antisera against terminally differentiated hemopoietic cells such as platelets, thymocytes, and macrophages and showing cross-reaction with the pluripotent stem cells from which these cells were derived. Quantitative absorption studies of each antiserum showed the antigens to be largely cell-lineage-specific. For example, the anti-stem cell activity in anti-platelet serum was not absorbed out with thymocytes or macrophages from the same mouse strain but was removed by absorption with platelets. Absorption of each antiserum with nonhemopoietic mouse tissues such as brain, kidney, liver, and testis did not reduce anti-stem cell activity. Thus, each antiserum was shown to be tissue specific and species specific. Hemopoietic cells from mouse strains other than CBA absorbed out most of the anti-stem cell activity indicating cell-lineage-specific antigens to be common to the mouse strains tested.

Animals↗
PubMed1979

Rat mutant (NZNU) showing "nude" characteristics.

A new rat mutant (nznu) is described which shows characteristics similar to those of the nude mouse. The mutant is an autosomal recessive. Homozygotes are essentially hairless (except for stunted vibriassae) and show deficient thymus gland development. Under conventional breeding conditions the mutants are difficult to raise and few survive weaning. The absence of functional thymus-derived lymphocytes in the nude rat is implied by (1) acceptance of histoincompatible skin grafts, (2) lack of response to the T cell mitogens phytohaemagglutinin and concanvalin A, and (3) absence of cells sensitive to alloantiserum directed against rat thymus-derived lymphocytes. Although total blood leukocytes from the nude rat were within the normal range, differential counting of leukocytes showed a 4-fold elevation of neutrophils and a 2.5-fold reduction of lymphocytes, compared with normal rats. Phenotypically normal heterozygotes gave values intermediate between nude and normal rats.

Animals↗
PubMed1979

Surface antigens of murine hemopoietic stem cells. I. Cross reactivity of antisera against differentiated hemopoietic cells with bone marrow stem cells.

A model of multiply marked hemopoietic stem cells proposed by Till (1) has been tested with respect to antisera raised against differentiated murine hemopoietic cells. When absorbed with erythrocytes, antisera against CBA mouse lymph node lymphocytes, thymocytes, peritoneal macrophages and platelets cross-reacted strongly with pluripotent stem cells (CFUs) in bone marrow as determined by inhibition of spleen colony formation in lethally irradiated mice. Absorption of ATS, antimacrophage serum and antiplatelet serum with hemopoietic cells other than those used to prepare the antisera (e.g., ATS with neutrophils and platelets, antimacrophage serum with neutrophils, thymocytes and platelets and antiplatelet serum with neutrophils and thymocytes) did not reduce the activity of these antisera for CFUs whereas absorption with the inoculating cell type greatly reduced anti-stem cell activity. Absorption of these antisera with non-hemopoietic tissues such as brain, kidney, liver and testis in general had little effect on antistem cell activity, although a significant loss of activity was observed following absorption of antiplatelet serum with kidney. The antistem cell activity in ATS, antimacrophage serum and antiplatelet serum does not appear to be caused by antibodies against histocompatibility antigens sine bone marrow stem cells from histoincompatible C57BL and Balb/c mice were also sensitive to antisera against CBA mouse hemopoietic cells. In contrast to these findings, antisera against erythrocytes showed little cross-reactivity with CFUs, indicating that few antigens are held in common between erythrocytes and CFUs. We propose that nucleated hemopoietic cells and platelets retain cell line specific antigens in common with pluripotent stem cells from which they were derived, and that the continued expression of these antigens during differentiation may be involved in the differentiation process.

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PubMed1976

Characterization of polysomes from Xenopus liver synthesizing vitellogenin and translation of vitellogenin and albumin messenger RNA's in vitro.

1. Conditions are described for the isolation of polysomes from the liver of Xenopus laevis. The method involves homogenization of liver in 0.2 M Tris-HCl pH 8.5, treatment with 2% Triton X-100 and subsequent sucrose density gradient fractionation of polysomes from a 10000 X g supernatant. 2. Vitellogenin synthesis was induced in male Xenopus liver by oestradiol treatment. Polysomes were isolated and vitellogenin-synthesizing polysomes characterized by their association with monospecific 125 I-labelled rabbit anti-vitellogenin antibody and by reaction with rabbit anti-vitellogenin immunoglobulins followed by indirect immunoprecipitation with goat anti-rabbit antibody. 3. Changes in liver polysome content following oestrogen treatment of male Xenopus are correlated with the appearance of vitellogenin synthesis using an organ culture assay. 4. RNA extracted from livers of oestradiol-treated male Xenopus and from purified polysomes is shown to code for the synthesis of vitellogenin-specific immunoprecipitable polypeptides in a rabbit reticulocyte cell-free protein-synthesizing system, a major component having a molecular weight of 210000. Xanopus liver RNA is also shown to code for the synthesis of an albumin-specific immunoprecipitable polypeptide of 74000 molecular-weight which coelectrophoresed with Xenopus albumin.

Albumins↗
PubMed1976

Translation of Xenopus liver messenger RNA in Xenopus oocytes: vitellogenin synthesis and conversion to yolk platelet proteins.

Xenopus liver vitellogenin and albumin mRNAs injected into Xenopus oocytes are correctly translated, as shown by specific immunoprecipitation and co-electrophoresis with purified Xenopus vitellogenin (molecular weight 210,000 daltons) and albumin (molecular weight 72,000 daltons). Vitellogenin made in oocytes under the direction of injected liver mRNA is unstable compared to other proteins made on injected messengers (such as albumin and globin) and endogenous oocyte proteins (including actin), the half-life of newly made vitellogenin being about 8 hr. Pulse-chase experiments with 35S-methionine show vitellogenin to be a precursor to yolk platelet lipovitellin (molecular weight 120,000 daltons), while 3H-serine labeling demonstrates conversion to phosvitin (molecular weight 34,000 daltons). In contrast, injected 3H-serine 35S-methionine-labeled Xenopus vitellogenin protein is not converted to yolk platelet proteins and is degraded rather slowly (half-life, 23, 29 hr). Phosphorylation of serine residues in phosvitin can be detected in oocytes injected with 32PO4 or gamma-32P-ATP; thus exogenously derived yolk platelet protein is further modified, or turned over, once it is within the oocyte. Moreover, vitellogenin made in oocytes programed with liver mRNA is phosphorylated. Thus phosphorylation, assembly into yolk platelets, and cleavage are events that do not require vitellogenin supplied by the normal pathoways involved in yolk formation (synthesis and post-translational modification in the liver, transport in the serum, and follicle cell-dependent pinocytosis). Vitellogenin mRNA sediments at about 29S in a sucrose-SDS gradient, while albumin messenger peaks at 16S; both species contain poly(A). These liver mRNAs are functionally stable in oocytes for at least 5 days. Vitellogenin-forming activity, relative to albumin, actin, or total endogenous activity, increases with time, and the final rate of 2-2.5 times the initial rate is only reached 3 days after injection. The potentiation effect probably stems from an increase in the efficiency of translation of vitellogenin mRNA. The availability of homologous mRNAs now permits injected messenger to be used as a valide probe of oocyte function; the biological activity of mRNA from a non-ovarian Xenopus tissue proves that some at least of the translational systems within the Xenopus oocyte are not cell type-specific. Moreover, the whole cell system is eminently suitable for assaying putative translational (and possibly transcriptional) control elements from frog liver.

Albumins↗
PubMed1975

Biogenesis of plasmalemmal glycoproteins. Intracellular site of synthesis of mouse liver plasmalemmal 5'-nucleotidase as determined by the sub-cellular location of messenger RNA coding for 5'-nucleotidase.

1. Free and membrane-bound mouse liver polyribosomes were separated by prolonged density-gradient centrifugation of the post-mitochondrial supernatant. RNA was extracted from free and membrane-bound polyribosomes and mRNA purified by oligo(dT)-cellulose column chromatography. 2. Antisera against purified mouse liver plasma membrane 5'-nucleotidase and moust albumin were prepared and characterized. 3. Microinjection of equivalent amounts of mRNA from free and membrane-bound liver polyribosomes into Xenopus laevis oocytes indicated by immuno precipitation and sodium dodecylsulphate gel electrophoresis a higher proportion of mRNA coding for 5'-nucleotidase and serum albumin in membrane-bound polyribosomes than free polyribosomes. 4. Although small, significant amounts of serum albumin and 5'-nucleotidase were also coded for by mRNA purified from free polyribosomes. The results suggest that in vivo, mRNA in mouse liver membrane-bound polyribosomes codes for the synthesis of 17 times more 5'-nucleotidase than does the mRNA in free polyribosomes.

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