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R C Braylan

Publications and source records attributed to R C Braylan.

At least 55 records · Page 3Linked to original sources
PubMed1993

Quantitative morphologic assessment of nuclei extracted from paraffin for DNA flow cytometry.

We present a method for quality control of flow cytometric DNA content studies using nuclei extracted from paraffin-embedded tissue. This method is based on a quantitative morphologic assessment of extracted nuclei. Cell nuclei prepared from 22 paraffin-embedded tumors known to contain discrete diploid and aneuploid stemlines were deposited onto poly-L-lysine-coated glass slides. Nuclei were stained with Diff-quic and examined by light microscopy. Two hundred nuclei were counted and classified based on morphologic appearance into tumor and nontumor groups. Classification criteria included differences in nuclear size, nuclear chromatin structure, the degree of nuclear chromatin condensation, and the presence of nucleoli. Excellent agreement was found between two independent observers (R = 0.989) on the classification of nuclei. The relative number of tumor nuclei on the morphologic preparation was compared with the relative number of aneuploid cells in the DNA histogram. Good agreement was observed (R = 0.975) in all but three cases in which the relative number of tumor nuclei was underrepresented by the percentage of aneuploid nuclei in the DNA histogram. In each case, further analysis by image cytometry demonstrated a diploid and aneuploid component of the tumor cell population. This quantitative method of morphologic examination of the preparation ultimately analyzed by flow cytometry offers several distinct advantages, including: (a) identification of peaks in the DNA histogram, (b) assessment for selective loss of cell nuclei in the extraction process, and (c) identification of biologic heterogeneity in tumor populations.

Cell Nucleus↗
PubMed1992

Reduced expression of CD20 antigen as a characteristic marker for chronic lymphocytic leukemia.

The surface antigens expressed by the cells of chronic lymphocytic leukemia (CLL) are well known. Most CLL are monoclonal B-cell lymphoproliferative disorders characterized by the coexpression of B-cell antigens and CD5, an antigen present predominantly on T cells. Very little attention, however, has been paid to the quantitative characteristics of the expression of B-cell antigens in CLL. In this study, we used flow cytometry to analyze the expression of CD20, a well-known B-cell-associated antigen, in lymphocytes from 42 cases of CLL and its tissue counterpart, small lymphocytic lymphoma (SLL), and compared the results with results obtained from the analysis of 21 follicular lymphomas, 20 hyperplastic reactive nodes, and 26 samples of normal peripheral blood. The intensity of CD20 expression in the CLL/SLL cells was significantly lower than that of B cells in the other categories. This antigen expression abnormality does not appear to be a universal phenomenon in CLL/SLL, since CD19, another pan-B antigen, was expressed in CLL/SLL at levels higher than those in follicular lymphomas and comparable to those in reactive lymph nodes. These results indicate that the low CD20 expression can be used as a marker for CLL/SLL. The few cases exhibiting intense CD20 expression may represent a biologically different disease. CLL/SLL cells faintly expressing CD20 also show concomitant low CD5 expression in a manner not observed in normal CD5-expressing B cells.

Adult↗
PubMed1992

Alterations of lymphocyte populations during development in the spontaneously hypertensive rat.

OBJECTIVE: Immune system abnormalities have been linked to hypertension in the spontaneously hypertensive rat (SHR). The goal of our study was to examine different lymphocyte subpopulations in the prehypertensive and developmental phases of hypertension in the SHR. DESIGN: Blood samples were obtained from SHR and Wistar-Kyoto (WKY) rats at the following time-points: 2 weeks and 1, 2, 3 and 4 months. Lymphocytes were separated from the whole blood. METHODS: Monoclonal antibodies were used to fluorescently label the following lymphocyte subpopulations; total T cells, T non-helper cells, T helper cells and B cells. Fluorescence-activated cell sorting (FACS) analysis was used to quantify the percentages of the different subpopulations examined. RESULTS: The T non-helper cell population was depressed in SHR from 2 weeks of age. This finding persisted throughout the entire 4-month study period. At the 4-month time-point, the total T cell percentage was also depressed in the SHR. CONCLUSIONS: These results demonstrate that immune system abnormalities are present in the prehypertensive and developmental phases of hypertension in the SHR. This supports the hypothesis that the immune system is involved in the development and maintenance of hypertension in the SHR, preceding not adapting to this state.

Animals↗
PubMed1991

Flow cytometric analysis of terminal deoxynucleotidyl transferase.

Terminal deoxynucleotidyl transferase (TdT) is a useful marker for lymphoid precursor cells. In this study, the authors used flow cytometry (FCM) to analyze TdT expression in human hematopoietic malignancies. Cells were fixed in 0.5% formaldehyde, briefly exposed to nonionic detergent, and subsequently labeled with mouse monoclonal anti-TdT antibodies followed by fluorescein-conjugated antimouse IgG and propidium iodide (PI), which was used for the simultaneous analysis of DNA content. Cells from 20 of 22 acute lymphoblastic leukemias (ALL), 4 of 7 mixed lineage leukemias, 2 of 21 acute myeloid and myelomonocytic leukemias, 1 of 2 chronic myeloid leukemias in blast crisis, 1 lymphoblastic lymphoma, and 1 thymoma were TdT positive. Cells from 13 nonlymphoblastic lymphomas, 3 myelodysplastic bone marrows, and peripheral blood mononuclear cells from 29 normal individuals were negative. An excellent correlation was seen between this assay, the conventional slide immunofluorescence technique, and an enzyme immunoassay method. The FCM assay detected as few as 2% blasts in mixing experiments of TdT-containing leukemic cells with normal peripheral lymphocytes. Furthermore, the combined analysis of TdT and DNA allowed the recognition of aneuploid TdT positive cells in four cases of ALL. The high sensitivity, the quantitative information obtained, and the capability of simultaneously analyzing DNA content make this method of TdT analysis more valuable than conventional techniques.

DNA Nucleotidylexotransferase↗
PubMed1989

High-grade B-cell lymphoma presenting as polyserosal disease. Diagnosis by flow cytometry.

Two patients presenting with anasarca were found to have aggressive B-cell lymphoma. No bulky disease was detected. The diagnosis was rapidly established by the flow cytometric analysis of cell surface immunophenotype and cell cycle fractions of pleural or peritoneal cells. Such presentation of lymphoma is unusual and previously undescribed, and it may have a significant negative prognostic impact. The authors' observations indicate that lymphoma be included in the differential diagnosis of anasarca and that flow cytometry can be useful for a fast confirmation of the diagnosis.

Aged↗
PubMed1989

Flow cytometric analysis of lymphomas.

Flow cytometry is rapidly developing as an important tool in the characterization of lymphomas. Analysis of cell surface antigens and DNA content in these tumors provides useful biologic information that can be applied advantageously to their diagnosis and classification. In this article we examine practical aspects of handling, preparation, and staining of lymphoid samples for flow cytometry and delineate approaches to data analysis and interpretation. We discuss specific applications, advantages, and limitations of the technique in the evaluation of neoplastic lymphoid diseases.

Evaluation Studies as Topic↗
PubMed1987

Correlation of monoclonal antibody phenotyping and cellular DNA content in non-Hodgkin's lymphoma. The Southeastern Cancer Study Group experience.

Flow cytometric measurements of DNA ploidy and synthetic (S) fractions are quantitative parameters that can aid in the diagnosis and classification of non-Hodgkin's lymphomas (NHL). Although the S-fraction correlates with histologic classification, the relationship between specific immunologic phenotypes and DNA ploidy is less well known. We investigated this relationship in 106 cases of NHL. Samples from 17 SEG institutions were sent for flow cytometry and for frozen section immunoperoxidase phenotyping. DNA histograms were analyzed for ploidy changes and cases classified by degree of abnormality. Ninety-eight cases were B-cell and eight were T-cell. B-cell tumors were subdivided by expression of antigens CD24, CD10, CD5, HB31, CD22, CD20, and transferrin receptor. Among B-cell tumors there was no correlation between degree of aneuploidy and phenotype, but B-cell tumors displayed a higher degree of aneuploidy than T-cell tumors (P less than 0.02). There was no difference between the S-fractions of B-cell and T-cell lymphomas. However, the transferrin receptor was more often expressed when the S-fraction was higher than 5%. Cases with S-fractions higher than 5% were more likely to lack any of the Pan-B antigens CD19, CD22 or CD20, and also were more frequently CD24 negative. We conclude that T-cell and B-cell NHL differ in degree of aneuploidy, and that monoclonal antibody phenotyping and DNA ploidy analysis independently define subgroups of B-cell NHL. Within B-cell lymphomas phenotype also correlates with grade of NHL as defined by the S-fraction.

Aneuploidy↗
PubMed1987

Flow cytometric analysis of DNA in bone and soft-tissue tumors using nuclear suspensions.

Ninety-four bone and soft tissue tumors were analyzed for their DNA content using flow cytometry (FCM). A simple, rapid method for preparing isolated nuclear suspensions was used. Tissues, minced in a hypotonic solution containing detergent and propidium iodide as a fluorescent probe for DNA, provided in most instances high nuclear yields from only 0.02 to 0.03 g of solid tumor. Whereas all nonneoplastic samples had a diploid DNA content, various degrees of abnormal DNA distributions were detected in 90% of the neoplastic samples and were present in benign as well as malignant tumors. Our findings demonstrate that FCM DNA analysis is practical in most musculoskeletal tumors and support the observations of others that abnormal DNA content may serve as a general neoplastic marker in these tumors.

Bone Neoplasms↗
PubMed1987

In vitro transformation of human B-cell follicular lymphoma cells by Epstein-Barr virus.

Human low-grade B-cell lymphoma cells cannot be readily maintained in long-term tissue culture. In an effort to obtain low-grade B-cell lymphoma cell lines for in vitro study, we used Epstein-Barr virus (EBV) as a transforming agent. T-cells were removed prior to EBV transformation by rosetting with sheep erythrocytes, followed by treatment with anti-T11 monoclonal antibody plus complement. The resulting cell population was cocultured with EBV prepared from tissue culture supernatants of marmoset cell line B95-8. Identical immunoglobulin gene rearrangements of tumor cells and EBV-transformed cells were the criteria used to determine that the transformed cells were of tumor origin. DNA was prepared from both biopsy tissue and EBV cell lines and digested with restriction endonucleases, and Southern blots were prepared by standard methods. B-cells isolated from biopsies of four low-grade B-cell lymphomas of follicular, small cleaved cell type and one of follicular, mixed cell type were transformed by EBV into rapidly growing in vitro tissue culture lines. Two of the five transformed cell lines had immunoglobulin heavy chain and light chain gene rearrangements which were present in cells from the original tumor biopsy, indicating that these EBV-transformed cell lines are of tumor origin.

B-Lymphocytes↗
PubMed1987

Flow cytometric analysis of DNA in cells obtained from deparaffinized formalin-fixed lymphoid tissues.

Flow cytometric analysis of DNA content was performed on nuclear suspensions prepared from fresh and from paraffin-embedded, formalin-fixed lymphoid tissues. We confirmed previous reports that it is possible to obtain nuclear suspensions from deparaffinized, formalin-fixed tissues, suitable for DNA analysis by flow cytometry. We observed a tendency for a larger coefficient of variation (CV) of the DNA measurements in the fixed tissues than in the unfixed material causing abnormalities in 2 of 19 lymphomas to become undetectable. Furthermore, samples from different paraffin blocks of a single tumor with an extra G1 (hyperdiploid) peak showed marked differences in the CV of the hyperdiploid peak while the CV of the diploid peak was similar in all samples. In both benign and malignant lymphoid tissues, the S-phase fraction was higher in paraffin-embedded tissues than in unfixed cells. This difference could be attributed to 4', 6'-diamidino-2-phenylindole dihydrochloride (DAPI), a DNA-binding dye commonly used in this technique. Nevertheless, intermediate and high grade lymphomas from paraffin-embedded tissues generally showed a greater S-fraction than low grade lymphomas, a similar observation as with unfixed tissues. Therefore, DNA content analysis of nuclei extracted from paraffin sections may be inadequate to resolve slight aneuploidy, but the measurement of S-fraction size may remain diagnostically or prognostically valuable. Large retrospective studies will be necessary to determine the clinical impact of this technique in the analysis of lymphomas.

Cell Nucleus↗
PubMed1987

Extraction of cellular DNA from human cells and tissues fixed in ethanol.

DNA can be extracted from ethanol-fixed lymphoid cells and tissues. The fixation procedure is simple and rapid, and the DNA extraction itself is the same as that normally used for fresh tissue or cells. DNA extracted from ethanol-fixed material is indistinguishable from DNA extracted from fresh samples based on its purity, its ability to be digested with restriction endonucleases, and its ability to specifically hybridize to DNA probes. The capability to extract DNA from ethanol-fixed cells and tissues eliminates the need for stringent handling and storage requirements of fresh or frozen specimens.

DNA↗
PubMed1987

Selective loss of expression of a tumor-associated antigen on a human leukemia cell line induced by treatment with monoclonal antibody and complement.

The sensitivity of a common acute lymphoblastic leukemia-associated antigen (cALLa)-positive, human leukemia pre-B-cell line to killing by antibody and complement was studied. A stable subpopulation was selected by its ability to survive four sequential treatments with excess monoclonal antibody (MoAb) directed against an Mr 24,000 glycoprotein associated with human leukemia cells and excess rabbit complement. Analysis of the antigen expression by individual cells within the parental and the selected cell populations was achieved by flow cytometry and demonstrated a marked decrease of the leukemia-associated antigen expression on individual cells within the selected subpopulation. These low-antigen-density cells were stable in subculture, and the immunoglobulin heavy-chain gene rearrangement of the parent population and the low-antigen-density subpopulation were identical, indicating that they were derived from a single cell source. The selection of this subpopulation was specific in that the expression of a second antigen recognized by a cALLa-specific MoAb was not affected. The presence of subpopulations of tumor cells with low levels of surface antigen expression that are resistant to killing upon addition of excess antibody and complement will prove to be an obstacle to the use of this approach to eliminate tumor cells from bone marrow that is to be used for autologous transplantation.

Antibodies, Monoclonal↗
PubMed1986

Analysis of neoplastic leukocyte surface antigens in unfractionated blood.

The detection of leukemic cells in peripheral blood is based on cytologic and cytochemical methods. Recently, the characterization of leukemic cells has been improved by the analysis of cell surface antigens. Abundant leukemic cells are relatively easy to identify. Small numbers of circulating leukemic cells, however, may be difficult to recognize by conventional or immunological techniques. This is of particular importance in treated patients in whom the presence of low levels of circulating leukemic cells may have considerable clinical relevance. We used multiparameter correlated flow cytometric analysis to detect and characterize human leukemia/lymphoma cells in small samples of unfractionated peripheral blood. Leukocyte surface antigens were labeled with monoclonal antibodies and simultaneous forward and right-angle light scatter and fluorescence signals were measured from each cell. An interactive computer program was written that permitted the two light scatter measurements to be displayed on the screen on a cell-by-cell basis (dot-plot). Subpopulations of interest could then be selected on the dot-plot for analysis of their fluorescence distribution. On the basis of their dual scatter properties and their antigenic profile, neoplastic leukocytes were recognized even in cases in which leukemic cells were infrequent and not detectable by conventional cytologic methods.

Animals↗
PubMed1986

The malignant cells in a Lennert's lymphoma are T lymphocytes with a mature helper surface phenotype. A multiparameter flow cytometric analysis.

The flow cytometric analysis of DNA content in cells obtained from a case of Lennert's lymphoma demonstrated the presence of a discrete hypotetraploid cell population. Correlated multiparameter analysis of DNA, light scatter, and surface antigens by flow cytometry showed that the hypotetraploid cells were intermediate to large cells expressing T11, T3, and T4 antigens and lacking B1 and T8 antigens. These findings suggest that Lennert's lymphoma represents a malignant neoplasm of T-helper lymphocytes.

Adult↗
PubMed1985

Anaplastic neoplasm in a patient with hairy cell leukemia.

A 63-year-old white man had a history of recurrent pneumonia, pancytopenia, and splenomegaly when the diagnosis of hairy cell leukemia was made on bone marrow biopsy examination. Splenectomy confirmed that diagnosis and his pancytopenia moderately improved. Three years following the diagnosis, the patient developed an upper abdominal mass involving the stomach wall that was found to be an anaplastic "large cell" neoplasm. Palliative radiotherapy was started, but the patient died 2 months later. Cytochemical studies of the anaplastic gastric neoplasm revealed cytoplasmic tartrate resistant acid phosphatase activity. Electron microscopy showed no epithelial differentiation. These observations suggest that the gastric neoplasm represented an evolution of hairy cell leukemia into a more aggressive tumor analogous to the transformation that occurs in other B-cell neoplasms.

Bone Marrow↗
PubMed1985

Production of heterologous antibodies specific for murine B-cell leukemia (BCL1) immunoglobulin by immunization with synthetic peptides homologous to heavy chain hypervariable regions.

Three peptides homologous to each heavy chain hypervariable region expressed by murine B-cell leukemia, BCL1, were synthesized in vitro by solid phase peptide synthesis. All three synthetic peptides elicited responses in rabbits which were immunized with synthetic peptide or synthetic peptide conjugated to the carrier keyhole limpet hemocyanin. Six individual rabbits were immunized, five of which responded by producing antisera which react specifically in radioimmunoassay with the synthetic peptide used as immunogen. One antiserum has specificity for the peptide homologous to the first hypervariable region, three antisera have specificity for the peptide homologous to the second hypervariable region, and one has specificity for the peptide homologous to the third hypervariable region. The five antisera with high titers of antibody recognizing synthetic peptide also specifically recognize native immunoglobulin M secreted by BCL1 tumor cells as demonstrated by immunoprecipitation followed by sodium dodecyl sulfate: polyacrylamide gel electrophoresis and autoradiography. These five antisera do not show reactivity with immunoglobulin secreted by spleen cells from normal BALB/cAn mice or by B-cells from unrelated tumors and cell lines. However, as determined by absorption experiments, the majority of antibodies in each antiserum are directed against the respective synthetic peptide, and only a small portion are reactive with native immunoglobulin M. Nonetheless, these results indicate use of synthetic peptides as a potential alternative source of immunogen for production of antitumor antibody.

Amino Acid Sequence↗