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G B Olson

Publications and source records attributed to G B Olson.

At least 37 records · Page 2Linked to original sources
PubMed1982

Computer-assisted morphometric analysis of radiation injury in murine lymphocytes.

Groups of mice were killed 1, 3, 7 and 15 days after whole body exposure to 0, 5, 50 or 500 rads of irradiation. Lymphocytes were harvested from the peripheral blood and spleen for total and differential leukocyte counts, for determination of the absolute numbers of thymic-dependent (T) and bone marrow-dependent (B) cells and the in vitro responsiveness to phytohemagglutinin (PHA), concanavalin A (Con A) and lipopolysaccharide (LPS) mitogens and for computer-assisted morphometric analysis (CAMA) of Feulgen-stained nuclei. Alterations in functional activity and morphometric composition showed the same trends with respect to radiation injury, with maximum effects observed three days after exposure. The spleen contained a greater proportion of altered cells than did the peripheral blood. Comparison of the results with similar data obtained from lymphocytes irradiated in vitro showed that the same micromorphometric descriptors serve to distinguish irradiated from control cells in both cases.

Animals↗
PubMed1982

Computer-assisted morphometric analysis of renal radiation response.

A single x-ray dose of 1,200 to 1,600 rads to the mouse kidney is associated with definite morphologic alteration but minimal functional impairment at six months; this progresses to profound structural and functional impairment by one year after irradiation. Subjective morphologic assessment of renal damage at six months correlates well with total radiation dose, fractionation schedule and energy characteristics of the radiation beam but does not provide adequate quantitative numerical data for sophisticated statistical tests of significance or for comparisons of effect variability at given dose levels. This investigation assessed the applicability of computer-assisted morphometric analysis (CAMA) for quantitation of effects and in making statistical comparisons of significance between kidneys subjectively classified as to degree of histologic alterations. Images of renal cortex tubular nuclei from the various histologic grades were digitized, recorded and analyzed with the CAMA system. Results indicate that the reliability of specific grade assignment by CAMA for individual nuclei was inadequate but that separation of irradiated and unirradiated renal tissue (bivariate group means) was quite distinct and of high reliability. Differences were present among the four irradiated histologic grades, but they were not marked, especially among the three highest grades. More accurate quantitation of nuclear size variations was achieved, and chromatin textural differences were detected that were not apparent to the eye. Computer-assisted morphometric analysis appears to have a valuable application in the quantification and analysis of chronic radiation effects.

Animals↗
PubMed1981

The automated analytical electrophoresis microscope.

The components of an automated computer-controlled analytical electrophoresis microscope (AEMS) are described. Computer tracking of migrating cells projected under phase contrast onto a vidicon permits the rapid taking of multiple velocity measurements per cell so that reliable determinations of electrophoretic mobilities thereby result. The computer-controlled cell search and tracking algorithms allow high speed operation so that statistically valid profiles and data bases can be collected rapidly. Initial electrophoretic mobility evaluations have been carried out on populations of lymphocytes, erythrocytes, and platelets.

Animals↗
PubMed1980

Cytophotometric studies of cell populations.

Technologic advances in the recording of digitized imagery have made the study of large cell populations by image analytical methods feasible. Computed image information provides quantitative, and novel, information that allows an exact measurement of minute changes in the chromatin distribution of cell nuclei, and the detection of subpopulations of cells or changes in the functional state of the cells. The sensitivity of the detection exceeds that of human observers; the specificity of the measured changes must be the subject of basic cell biologic research.

Animals↗
PubMed1980

Microphotometric differentiation of human T and B cells tagged with monospecific immunoadsorbent beads.

A comparative and statistical study was done of the classification of peripheral blood lymphocytes (PBLs) as T cells, B cells and monocytes by various immunologic procedures and computerized microphotometric analysis. PBLs from 15 healthy male subjects were examined by immunofluorescence, E rosettes, and immunoadsorbent beads (IAB) for T cells and B cells, by phase contrast microscopy and as fixed slide preparations. Cells tagged with IAB for T cells and B cells were fixed, stained with Papanicolaou stain and analyzed. Evaluation of immunologic data shows 50% to 57% T cells, 9.7% to 24.1% B cells, 13.4% to 16.1% monocytes and about 20% unmarked cells. Analysis of T cells shows significant correlations between E and T cell-IAB rosettes, but neither rosetting procedure reveals a positive correlation with immunofluorescence-labelled T cells. Comparison of B cells shows an insignificant correlation between B-cell IAB and immunofluorescence. Results showed that permanent slides of rosetted cells can be made without alteration in relative numbers of rosetted cells. Assessment of immunologically tagged cell samples by image analysis correctly classified 80% to 90% of cells as T and B cells. Evaluation of homogeneity of the T and B cell populations shows the existence of four subsets of B cells and five subsets of T cells.

B-Lymphocytes↗
PubMed1980

Image analysis of hepatocyte nuclei from chlordane-treated rats.

The treatment of rats with hepatic dysfunction with chlordane at below the "no-effect" dose produces an increase in the number of hepatocyte nuclei with doubled DNA content. More important, though, it can be shown that even cells with unaltered DNA contents undergo statistically significant changes in their chromatin distribution pattern. Thus, image analysis techniques are capable here of detecting and substantiating toxic effects not apparent by visual inspection.

Animals↗
PubMed1979

Characterization of murine T and B cells by computerized microphotometric analysis.

Splenocytes and column-separated T cells are differentiated into subpopulations of T and B cells on the basis of computer-assisted morphometric analysis of Feulgen-positive nuclear DNA. Differentiation is based upon the analysis of computable image information related to DNA distribution patterns. The technique at the present time does not allow immunofluorescent and morphometric measurements to be made on a given cell. However, the differentiation obtained by using descriptors proven capable of detecting pure populations of T and B cells shows excellent agreement with the differentiation obtained by immunofluorescence analysis. The descriptors and decision rules used the discrimination among splenocytes are reproducible from one experiment to another and remain valid for the differentiation of lymphocytes from animals of different sex and strain.

Animals↗
PubMed1979

Subclassification of murine T cells by computerized microphotometric analysis.

Splenocytes separated by physical means and classified as T cells bay immunologic tests and computerized microphotometric analysis are differentiated into subgroups by analysis of the distribution patterns of Feulgen-positive nuclear DNA. In like fashion T cells obtained as purified preparations after separation on a nylon column, and accepted as T cells by micromorphometric analysis were subjected to further computerized morphometric analysis of nuclear DNA to form subgroups of cells. In each case, the number and composition of the detected subgroups were consistent. The classification does not appear to reflect any obvious phases of the cell cycle and is not dependent upon the sex and strain of mice from which the cells were obtained.

Animals↗
PubMed1979

Computer analysis of defined populations of lymphocytes irradiated in vitro. III. Evaluation of human T and B cells of peripheral blood origin.

The radiosensitivities of lymphocytes of peripheral blood origin obtained from two healthy 45 year old male donors were studied simultaneously at yearly intervals over a three year period. Hypaque-Ficoll purified cells were exposed in vitro to 0, 5, 50, and 500 rads and then evaluated serially for viability of T and B cells, responsiveness to PHA and Con A, and morphologic evidence of injury as documented by standard light microscopy and computer assisted morphometric analysis. The results showed that T cells in both subjects were less radiosensitive than B cells. Differences between the two subjects also existed in the radiosensitivity of these two subpopulations of lymphocytes, differences that remained constant over the three years period of observation. The differences correlated with similar discrepancies in mitogenic responsiveness and are thought to relate to variations in the relative proportions of subpopulations of T and B cells. In the mouse, T and B cell subpopulations differ in radiosensitivity. The data reported herein are consistent with a similar situation in man.

Adult↗
PubMed1978

Discrimination between human T and B lymphocytes and monocytes by computer analysis of digitized data from scanning microphotometry. I. Chromatin distribution patterns.

Digitized images of Feulgen-stained normal human B and T lymphocytes and monocytes were analyzed by computer and microphotometry. The algorithms assessed the chromatin distribution patterns. A substantial number of parameters descriptive of the chromatin distributions were found to show statistically highly significant differences between B and T cells and monocytes. Although the effects of a number of biologic variables, such as cell cycle phase and immune stimulation, need to be carefully evaluated, the preliminary results indicate potential for automatic classification and subclassification of human B and T lymphocytes in normal and disease states.

Adult↗
PubMed1977

Radiosensitivity of T and B lymphocytes. IV. Effect of whole body irradiation upon various lymphoid tissues and numbers of recirculating lymphocytes.

Groups of 10-week-old female CBA/J mice were exposed in whole body fashion to 0,5,50, and 500 rads and sacrificed in serial fashion 1,3,5,7,9,15, and 30 days after irradiation for morphologic evaluation of thymus, spleen, lymph node, and Peyer's patch, and assessment of the relative numbers of thymus-derived (T) and bone marrow-derived (B) cells in these tissues. The absolute and relative numbers of recirculating T and B cells mobilizable by thoracic duct cannulation were also determined and compared with similar determinations with respect to peripheral blood lymphocytes. B cell depletion occurred more quickly and was more pronounced in spleen and lymph node than T cell depletion at all three exposure doses. Depletion of T and B cells was roughly equal in peripheral blood and thoracic duct lymph. When present, regeneration of the T cell component occurred more rapidly than did B cell restoration. The latter often was incomplete at the time of the final sacrifice (day 30). PHA-responsive and Con A-responsive cells also appeared to differ with respect to the kinetics of cell death after whole body irradiation.

Animals↗
PubMed1976

In vitro activity of guinea pig transfer factor released into plasma.

Plasma fractions and plasma dialysate from 2,4-dinitrochlorobenzene- and tuberculin-sensitive guinea pigs that had been treated with either antilymphocytic serum or normal control serum were analyzed for their ability to transfer lymphocyte transformation, passive cutaneous anaphylaxis, and macrophage migration inhibition, as well as delayed hypersensitivity in vivo. Antilymphocytic serum caused rapid release of material, which has characteristics of transfer factor, into the plasma. It was dialyzable, migrated electrophoretically with the alpha globulins and albumin, possessed a 280/260 (nm) optical density ratio of 0.7, and caused in vitro lymphocyte transformation in the presence of the specific antigen. Passive cutaneous anaphylaxis antibodies were also present in the plasma of sensitive animals, but they were isolated in electrophoretic or dialysis fractions separate from those containing transfer activity.

Albumins↗
PubMed1975

Computer analysis of defined populations of lymphocytes irradiated in vitro. II. Analysis of thymus-dependent versus bone marrow-dependent cells.

Three uniform populations of T and B cells exposed to varying amounts of x-irradiation are examined utilizing computer-assisted morphometric analysis. These populations are: thoracic duct lymphocytes (TDL) from congenitally athymic (nude) mice (B cells); TDL from CBA mice treated with anti-Ig plus complement (T cells); and computer-selected untreated T cells from CBA TDL. Irradiated B cells show a more even dispersion of the nuclear chromatin and a dose-dependent increase in relative nuclear area beginning with the lowest dose evaluated (50 rads); no significan change in total optical density (OD) is demonstrable over the dose range evaluated (0 to 2000 rads). Anti-Ig-treated irradiated T cells demonstrate an initial shift toward lower OD values as a function of dose followed by a marked rise of OD values at 2000 rads, where numerous densely staining Feulgen-positive aggregates are identified. The relative nuclear area of this cell population also shows a biphasic response to radiation injury with an initial increase at the lower dose levels followed by a progressive decline to approximate control levels at 2000 rads. This effect is mirrored by the alteration in total OD which, after a decrease at low dose levels, approximates control values at 2000 rads. The computer-selected T cells show little change in OD values at the low-dose levels but show a marked increase in the more densely staining Feulgen-positive material following 2000 rads. This population reveals no apparent change in either relative nuclear area or total OD as a function of dose. Thus, untreated computer-selected T cells exhibit remarkably little evidence, morphologically, of radiation injury of doses associated with pronounced alterations on the part of B cells. In addition, treatment of a mixed cell population (CBA TDL) with anti-Ig plus complement to remove the B cells appears to alter the response of the residual T cells to radiation injury. These results, in conjunction with recent evidence to support the concept that T cells possess surface Ig, suggest that an Ig-anti-Ig interaction may alter the radiosensitivity of T cells.

Animals↗