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PubMed1975

Morphologic and functional characteristics of bone marrow macrophages from imferon-treated mice.

The iron storage macrophage has been isolated from the marrow of Imferon-treated mice and studied in vitro by morphologic, histochemical, and functional tests and isotope labeling techniques. These macrophages on stained preparations are large, many times binucleate cells (up to 150 mu), and show Prussian blue reactivity. In Epon-embedded, stained thick sections they contain elongated narrow basophilic inclusions. These macrophages are actively phagocytic and pinocytic; histochemical studies show that these cells are rich in acid phosphatase, nonspecific esterase, and PAS diastase-resistant activity. Iron storage macrophages do not incorporate the 3H-thymidine. The electron microscopic appearance of this macrophage shows that the cell has ferritin free in the cytoplasm and several types of cytoplasmic granules: those with large quantities of electron-dense ferritin and/or hemosiderin (type A), elongated granules (type B) with moderately electron dense homogeneous matrix and some ferritin at the periphery, and granules with heterogeneous content (type C). The above findings demonstrate that the iron storage cell is a mature macrophage which contains hydrolases, ferritin, and a unique population of cytoplasmic granules which are lysosomal in nature. There is some evidence to suggest that the unusual lysosome (type B granule) occurs after macrophages have ingested erythrocytes.

Acid Phosphatase↗
PubMed1975

Recognition by pregnancy serums of non-HL-A alloantigens selectively expressed on B lymphocytes.

A group of alloantibodies are found in pregnancy sera which react with antigens present on B lymphocytes and monocytes but are not detectable on the vast majority of unstimulated T cells. This specificity distinguishes them from HL-A antibodies which react with both cell types. They were readily recognized through indirect fluorescent antibody analysis by employing the combination of B-cell lymphoid lines and normal peripheral blood T cells. Different sera gave a variety of patterns of reactivity with a panel of 11 lymphoid lines. Similar differential patterns were also observed with normal B cells from different individuals particularly after concentrating the B cells. The antibodies were also cytotoxic to B cells and this procedure gave parallel results to the fluorescence method. The pattern of reactions obtained indicated a very heterogeneous system similar to that for HL-A. Special study of certain of the sera provided evidence that the lymphocyte-defined determinants of the mixed lymphocyte reaction system were involved. For convenience the term HL-B has been employed for these antigens.

Antibody Specificity↗
PubMed1975

[Demonstration of immunoglobulin determinants on lymphocyte surfaces by membrane immunofluorescence].

Isolated lymphocytes from peripheral blood of 22 healthy donors were examined with the help of the indirect membrane immunofluorescence (MIF) for immunoglobulin determinants on the surface of the cells. The quantity of MIF+-cells for IgM was on the average 8.7% (3-18) and for IgG 15.5%(8-18). Five different anti-IgM-sera were characterised with regard to their use in the MIF (precipitation titre, entire protein content, content of anti-IgM-antibodies). Differences in the quantity of the MIF+-lymphocytes were above all based on differing antibody concentrations of the sera. It was referred to further possible causes for these differences. The influence on the results of the examinations by protein addition and trypsination.

Adult↗
PubMed1975

[Cytotoxic effects of a leukocidin from Staphylococcus aureus (author's transl)].

In an attempt to improve the assay of leukocidin from Staphylococcus aureus a combined vital fluorochrome staining procedure with acridine organe and ethidium bromide was developed. It proved to be more suitable for the demonstration of leukocidic effects on leukocytes than phasecontrastmicroscopy. Damaged leukocytes fluoresced distinctly red and undamaged leukocytes green. With the fluorochrome-method leukocidic changes became also evident in some lymphocytes. These were not clearly demonstrated by phasecontrastmicroscopy.

Acridines↗
PubMed1977

[Morphological diagnosis of Pneumocystis carinii].

Pneumocystis carinii pneumonia can only be diagnosed once the microorganism is demonstrated. The authors review and illustrate various staining technics, and discuss for each of them specific advantages. All samples must by systematically examined both by phase contrast microscopy and by light microscopy after Gomori-Grocott and Gram-Weigert stains. This morphological study is completed by ultrastructural photographs.

Humans↗
PubMed1976

Cell separation using fluorescence emission anisotropy.

The emission anisotropy of selected fluorescent probes which interact with cells and their membranes is a sensitive parameter for studying the structural changes associated with different functional states. Such measurements can now be made on individual living cells at rates of up to 103 per second and the cells separated on the basis of the anisotropy function alone or combined with other physical signals using a multiparameter automated computer-controlled cell separator (MACCS). Thus, selection can be on the basis of simple or complex algorithms reflecting the size, macromolecular content, and rotational mobility of cellular components or liganded reporter molecules. Cells isolated in this manner are sterile, viable, and can be used for outgrowth or biochemical studies related to dynamic changes occurring during differentiation or malignant transformation.

Animals↗
PubMed1977

[Fluorescence microscopy demonstration of mitochondria in tissue culture cells using berberine].

The possibility of fluorescence microscopical examination of mitochondria in living animal cells using fluorochrome berberine sulphate is shown. At concentrations of 30--50 g per ml the chemical is accumulated selectively in mitochondria of living cells. The specificity of berberine sulphate accumulation in mitochondria was shown by comparative phase contrast and fluorescence microscopy. The advantages of the method is its high sensitivity and simplicity, especially when mitochondria can not be examined by the phase contrast microscopy.

Animals↗
PubMed1977

[Methods for the biological testing of dental materials on cell cultures].

This paper discusses some of the methods used by for making basic biological tests of stomatological materials. Although we do not dispense with the use of methods based upon the observation of fixed and, possibly, stained cells and allowing the states assumed by cells in a certain period of time to be noted, yet we believe that far better results may be obtained from tests enabling the development of changes of living cells cultivated in vitro to be followed. The results of the experiments conducted by the authors indicate that it is possible for the final effect to be modified in dependence upon the type of material used, its concentration, or the time allowed to elapse from the preparation of the particular material and that an observation of living cells procides much more information about the character of alterations and, more specifically about the time course of changes. If necessary, this method may be supplemented by an electronmicroscopical analysis of the changes produced.

Cells, Cultured↗
PubMed1978

[Morphological virus diagnosis--electron microscopy study of animal viruses with negative contrast procedure].

Reported in this paper are results obtained in morphological virus diagnosis by using the negative contrast technique on the basis of electron microscopy. The availability of high-efficiency electron microscopy as well as of perfectly improved techniques of preparation, knowledge of the latest virus model concepts, and indivudual skills in diagnosis are essential conditions for the above approach. Parvoviridae, picornaviridae, and togaviridae are identifiable only in high particle concentrations and by group representation. Papovaviridae, adenoviridae, herpetoviridae, poxviridae, and reoviridae, on the other hand, can be safely identified even as single particles. The diagnosis of orthomyxoviridae, paramyxoviridae, rhabdoviridae, and retroviridae is facilitated by their own dimensions and their characteristic helico-symmmetrical nucleocapside. Coronaviridae are of highly conspicuous morphology but, nevertheless, pose problems in differential diagnosis. Substantive improvement of morphological virus diagnosis, in terms of minute details, may be achieved by means of the negative contrast method on the basis of immune electron microscopy. Advantages implied in that morphological method include less time-consuming and quite uninvolved practicability and good dependability of diagnosis for more efficient decision-making in research and practice.

Animals↗