48 research outputs found

    Doing synthetic biology with photosynthetic microorganisms

    Get PDF
    The use of photosynthetic microbes as synthetic biology hosts for the sustainable production of commodity chemicals and even fuels has received increasing attention over the last decade. The number of studies published, tools implemented, and resources made available for microalgae have increased beyond expectations during the last few years. However, the tools available for genetic engineering in these organisms still lag those available for the more commonly used heterotrophic host organisms. In this mini-review, we provide an overview of the photosynthetic microbes most commonly used in synthetic biology studies, namely cyanobacteria, chlorophytes, eustigmatophytes and diatoms. We provide basic information on the techniques and tools available for each model group of organisms, we outline the state-of-the-art, and we list the synthetic biology tools that have been successfully used. We specifically focus on the latest CRISPR developments, as we believe that precision editing and advanced genetic engineering tools will be pivotal to the advancement of the field. Finally, we discuss the relative strengths and weaknesses of each group of organisms and examine the challenges that need to be overcome to achieve their synthetic biology potential.Peer reviewe

    B-cell lymphoma lacking Fc- and C3d-receptors.

    No full text
    Various cell surface markers were studied in a patient with lymphosarcoma cell leukemia. The B-cell derived feature of the neoplastic cells could be identified by demonstration of monoclonal surface immunoglobulin of IgM-kappa type of high density synthesized by the cells. Interestingly, there were no Fc- nor C3d-receptors demonstrable using various techniques. Only 22% of the leukemic cells expressed C3b receptors. The failure of rosette formation with mouse erythrocytes was an additional surface feature distinguishing from ordinary chronic lymphatic leukemia of the B cell type. The phenotype of the leukemia cells is discussed as corresponding to that of a less differentiated B lymphocyte

    Monoclonal antibodies against differentiation antigens of lymphopoiesis.

    No full text

    Leukamiezell - analyse bei der Diagnose der all/aul: Klinische wertigkeit heute verfügbarer Methoden.

    No full text
    After morphology and cytochemistry, immunological leukemic cell diagnosis became a generally available method by the development of monoclonal antibodies. Besides an otherwise not possible classification of nonmyeloid leukemias according to T- or B-differentiation status, precision and standardization of leukemia diagnosis is accomplished by immunodiagnostic means in an experimental way, an important point for therapy studies. In children, the common ALL - a precursor B-ALL type - was prognostically more favorable than the T-ALL which differs also in clinical appearance and in prognostic factors. In adults, however, T-ALL had a better prognosis than common ALL in a prospective trial. The heterogenous Null-ALL which makes up 23% of ALL in adults and 5% in children, was the prognostically most unfavorable form besides the rare B-ALL (1-2%), the immunophenotype being an independent prognostic variable. Immunodiagnostic means are therefore of utmost clinical importance compared to other methods such as cytogenetic and electron microscopy that are not performable in a corresponding extent

    Quantitative <sup>125</sup>J-Autoradiographie einzelner Zellen.

    No full text
    Das nach der Energie seiner &beta;-Zerf&auml;lle zwischen Tritium und Kohlenstoff-14 liegende Isotop 125J wurde auf seine Eignung zur quantitativen Autoradiographie gepr&uuml;ft. Absorption und Geometrie-Faktoren der radioaktiven Strahlung wurden untersucht. Hieraus lie&szlig;en sich geeignete Me&szlig;bedingungen entwickeln. Durch gleichzeitige Exposition von radioaktiven Referenzquellen k&ouml;nnen absolute Radioaktivit&auml;tsmengen ermittelt werden. Als Referenzquellen sind membranmarkierte Standardzellen geeignet, die den physikalischen Eigenschaften des Isotopes Rechnung tragen. Hierzu wurden enzymatisch radiojodinierte Schaferythrozyten auf ihre Eignung gepr&uuml;ft. Die absolute Zahl von antigenen Stoffen auf den Oberfl&auml;chen einzelner Zellen erh&auml;lt man, wenn man die spezifische Aktivit&auml;t der markierten Antik&ouml;rpermolek&uuml;le bestimmt und die Silberkorndichte der zu untersuchenden Zellen und der Standardzellen mi&szlig;t. Die Radioaktivit&auml;t pro Standardzelle wird in herk&ouml;mmlicher Weise ermittelt. Die neue Methode wurde zur Quantifizierung membrangebundener Immunglobulinmolek&uuml;le vom IgG-Typ auf einzelnen menschlichen Lymphozyten angewendet. Hierbei ist die Ermittlung einer immunologischen S&auml;ttigung des markierten Antik&ouml;rpers wesentlich. Auf Lymphozyten von Normalpersonen und von chronisch-lymphatischen Leuk&auml;miepatienten konnten sehr unterschiedliche absolute Immunglobulinmengen bestimmt werden. &nbsp

    Changes in &#39;A&#39; antigenic sites in haematological disorders. An immunoautoradiographic study.

    No full text
    Using a quantitative immunoautoradiographic technique with simultaneously exposed internal standards, antigenic sites on A1, A1B, A2 and A2B erythrocytes were quantitated. The binding of purified radioiodinated rabbit anti-A antibodies was studied by the direct incubation technique. 61 normal individuals and 44 patients suffering from leukemia and other haematological disorders such as polycythaemia vera (PV) and aplastic anaemia (Apl.A) were investigated. Among the normal volunteers, antigenic sites gradually increased up to 3 months of life, later on they were comparable with the values of adults. A reduction of more than 50% in the antigenic sites was observed in all cases of Apl.A. 50-70% of patients with various forms of leukaemia had a decrease in antigenicity. 1 patient suffering from acute unclassified leukaemia showed two populations of red cells. This case differed from natural O/A1 chimerism where A1 erythrocytes had normal antigenicity while in the patient, A1 antigens were depressed. 2 patients (1 with acute lymphoblastic leukaemia, 1 with Apl.A) who were investigated after allogenic bone marrow transplantation had a marked decrease in antigenic sites. Reasons for A antigenic variations in haematological disorders are discussed

    Akute thrombocytopenische Purpura mit thrombocyt&auml;ren Antik&ouml;rpern gegen Acetylsalicyls&auml;ure.

    No full text
    This case report deals with drug-induced allergic thrombocytopenia with lethal issue resulting from Thomapyrin&reg;. It was possible to demonstrate the in vitro existence of a high antibody titer against platelets. The complement-binding antibodies were directed specifically against the acetylsalicylic acid, a component of Thomapyrin&reg;, but did not react against its phenacetin component. The clinical picture pointed to cross-reactive allergic reactions of various cell systems, in particular of the hemopoietic precursor cells. The destructive course of the cytopenia can be explained by the continuous intake of the drug. The rare occurrence of this thrombocytopenia caused by Aspirin&reg;-until now, antibodies have been immunologically proven by only one author-renders the diagnosis of this life-threatening disease quite difficult

    Quantitative immunoautoradiography at the cellular level. I. Design of a microphotometric method to quantitate membrane antigens on single cells using 125I-labeled antibodies.

    No full text
    Iodine-125 has become a commonly-used radioisotope, especially for immunoautoradiographic investigations. Microphotometry of grain density, a well-established method in autoradiography with tritium and carbon-14, was applied to nucleated cells with 125I-labeled membranes. Geometric and absorption factors of radiation were investigated in order to find suitable conditions for quantitative evaluation. A preparatory device is given and a set-up of appropriate measuring conditions is presented. With these prerequisites the reflected-light bright-field photometry of immunoautoradiographs permits to determine automatically the content of surface antigens of single cells. Measurement examples were demonstrated
    corecore