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Biomedical subjects

R C Braylan

Publications and source records attributed to R C Braylan.

At least 73 records · Page 4Linked to original sources
PubMed1984

Cellular DNA of human neoplastic B-cells measured by flow cytometry.

Flow cytometric analysis of DNA of tumor cells rapidly provides information on cell kinetics and tumor ploidy. Human B-cell lymphomas, however, often contain high numbers of nonneoplastic cells, mainly T-lymphocytes, which may hamper the accurate measurement of cell cycle phases and ploidy level of these tumors. The neoplastic cells in each B-cell lymphoma express a single immunoglobulin light chain. Therefore, we labeled surface immunoglobulin light chains to discriminate between predominantly neoplastic B-cells and nonneoplastic cells in the same tissues. Using this label as well as antibodies against nonneoplastic T-cells, we performed multiparameter correlated flow cytometric analysis of 52 human B-cell lymphomas measuring cellular DNA in neoplastic and nonneoplastic populations from the same tissues without physical separation of cells. Comparison of cellular DNA of immunoglobulin light chain-bearing neoplastic cells with that of nonneoplastic cells from the same tumor enabled us to detect DNA changes (aneuploidy) in almost 80% of the lymphomas, an incidence higher than observed previously by conventional DNA analysis of unseparated cells. These ploidy changes were confirmed by comparing in the same tumor the DNA of normal T-cells with that of predominantly neoplastic cells. The proportion of neoplastic cells in the synthetic phase of the cell cycle (S-fraction) varied widely from tumor to tumor. Lymphomas with high neoplastic S-fractions (higher than 10%) were mostly hyperdiploid tumors and histologically corresponded to intermediate- and high-grade unfavorable lymphomas. Tumors with low neoplastic S-fractions (less than 5%) were predominantly diploid and near diploid, histologically low-grade lymphomas. Six lymphomas showed two discrete cell populations bearing the same immunoglobulin light chain but containing different amounts of DNA suggesting the presence of two neoplastic clones in the same tumor (biploidy). In two patients in whom the lymphoma relapsed at 17 and 34 months, respectively, after the initial biopsies, repeat tumor samples were obtained. Despite an increase in the neoplastic S-fraction, no change in ploidy level was observed in either case. Light scatter analysis suggested a relationship between cell size and genomic size; large cells in these tumors were mostly presynthetic aneuploid cells. The ability to measure DNA, antigens, and cell size in individual cells in a rapid, correlated manner is a unique attribute of flow cytometry.(ABSTRACT TRUNCATED AT 400 WORDS)

B-Lymphocytes↗
PubMed1983

Distinctive expression of the T4 antigen in normal and stimulated lymphocytes.

Correlated light scatter and fluorescence flow cytometric analysis of human peripheral blood lymphocytes showed that the expression of the T4 antigen was higher in the larger lymphocytes than in the smaller lymphocytes. A similar expression pattern was observed for HLA Class I antigens but not for T3 and T8, whose expression was independent of cell size. Results with lymphocytes from spleen, lymph node, and tonsil were comparable to those of peripheral blood. Thymocytes, however, were smaller and expressed less T4 and T8 than peripheral lymphocytes. In studies of lymphocytes stimulated in vitro with allogeneic cells or pokeweed mitogen, two populations of T4-positive cells were observed: one of large cells expressing high amounts of T4 and one of small cells expressing low amounts of T4. Similar patterns were seen with T8, although less consistently. In contrast, the expression of T3 was the same in both large and small cells. The large cells expressing high amounts of T4 were not restricted to cells engaged in DNA synthesis or mitosis. This was established by selectively analyzing cells in the G0G1 phases of the cell cycle and by studying stimulated lymphocytes no longer undergoing proliferation. Taken together, these results suggest that immature T lymphocytes are small and express low amounts of T4 and T8. We postulate that as they differentiate, cell size and T4 expression increase proportionally, both parameters increasing even further after antigenic or mitogenic stimulation. The quantitative expression of T4, and probably of T8 but not of T3, is therefore intimately related to maturation and activation of lymphocytes, a fact that may conceivably be related to a functional role of these surface molecules.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1983

The reversal of myelofibrosis associated with chronic myelogenous leukemia after allogeneic bone marrow transplantation.

A 20-year-old male with chronic myelogenous leukemia (CML) and severe bone marrow fibrosis underwent splenectomy, then ablative chemotherapy, followed by bone marrow transplantation from a histocompatible sister. The myelofibrosis completely resolved. Prompt marrow engraftment and disappearance of Philadelphia chromosome positive cells were documented. Therefore, the presence of marrow fibrosis which frequently accompanies CML is rapidly reversible following high dose chemotherapy and is not indicative of a hostile microenvironment which could preclude marrow transplantation for patients with CML and myelofibrosis.

Adult↗
PubMed1983

Flow cytometry.

Flow cytometry (FCM) allows the rapid measurement of a variety of physical and biochemical properties of individual cells suspended in a liquid medium. Recent developments now allow FCM to assess cellular properties with a speed and precision unobtainable by any other means. Because of its multiple capabilities, FCM is being used for ever greater numbers of applications, in both basic and applied biology, and its expected soon to be widely used in the clinical laboratory.

Antigens, Surface↗
PubMed1982

Correlated analysis of cellular DNA, membrane antigens and light scatter of human lymphoid cells.

Flow cytometric correlated analysis of membrane antigens, DNA, and light scatter was performed on human lymphoid cells using fluorescein (FITC)-conjugated antibodies to label B- and T-cell antigens and propidium iodide (PI) to stain DNA after ethanol fixation and RNase treatment. A FACS II flow cytometer was modified to obtain digitized measurements of two color fluorescence and light scatter emissions, simultaneously. Software was written to allow single parameter analysis or correlated analysis of any two of the three parameters acquired. Ethanol fixation preserved FITC surface labeling for at least 15 weeks, but produced marked changes in light scatter. No changes in FITC distributions were observed after RNase treatment and PI staining, and the presence of FITC labeling did not affect DNA distributions. Within heterogeneous cell populations, the DNA distribution of cell subpopulations identified by a membrane antigen was clearly demonstrated.

Antigens, Surface↗
PubMed1982

Hyperparathyroidism and anemia in chronic renal failure.

The clinical course of an adolescent on chronic hemodialysis with severe hyperparathyroidism, osteodystrophy and profound anemia is described. After 1,25,dihydroxycholecalciferol was instituted for therapy, bone disease improved as evidenced by radiographic findings. Transfusion requirements diminished and bone marrow fibrosis on serial biopsies decreased significantly. These therapeutic results link hyperparathyroidism with the pathogenesis of anemia in chronic renal failure.

Anemia↗
PubMed1982

Lymphomas and their expression in peripheral blood.

Circulating malignant cells may be demonstrated in patients with lymphoma. Whereas Hodgkin's disease rarely if ever becomes leukemic, the non-Hodgkin's lymphomas often express varying numbers of neoplastic cells in peripheral blood. The incidence of leukemic manifestation in these patients correlates with the histologic subtype of the lymphoma. Pure morphologic examination of neoplastic circulating cells may not be sufficient to recognize the presence of lymphoma or to diagnose its type. The application of modern laboratory techniques such as enzyme histochemistry, cell surface markers and cell kinetics, may be very helpful in demonstrating the presence of circulating lymphoma cells in recognizing their type.

Diagnosis, Differential↗
PubMed1981

Simultaneous analysis of DNA and cell surface immunoglobulin in human B-cell lymphomas by flow cytometry.

Cell suspensions prepared from human B-cell lymphomas were analyzed for cellular DNA and cell surface immunoglobulin (SIg) by flow cytometry. In addition to SIg-bearing neoplastic B-lymphocytes, these tumors contain nonneoplastic cells. Flow cytometry permitted selective analysis of DNA in subpopulations defined by the membrane antigen SIg and also permitted analysis of SIg of subpopulations defined by DNA content. Because measurements of DNA and SIg were made simultaneously on each cell, physical separation of cells was not required. Using propidium iodide as a fluorescent DNA probe and fluorescein isothiocyanate-labeled antibodies to stain SIg, differences in cellular DNA between SIg-bearing neoplastic cells and nonneoplastic cells from the same tissues could be demonstrated. Additionally, this simultaneous correlated analysis allowed assessment of the cell cycle dependence of SIg expression. Mean fluorescein isothiocyanate (Slg) fluorescence was greater in S- than G1-phase cells, but the ratio of mean fluorescein isothiocyanate fluorescence of cells in S phase to that of cells in G1 phase varied for different tumors.

B-Lymphocytes↗
PubMed1980

Immunological markers and DNA content in a case of giant lymph node hyperplasia (Castleman's disease).

Little is known about the immunologic characteristics of the cells in giant lymph node hyperplasia (GLNH). For this reason, cell surface markers and intracytoplasmic immunoglobulins were determined on a case of GLNH. In addition, cellular DNA content was determined by flow analysis. A 59-year-old male underwent thoracotomy for a posterior madiastinal mass, which was entirely excised. Histologically, the mass was diagnosed as GLNH with features of both the hyaline-vascular and plasma-cell types. Preoperatively, the patient had a broad-based hypergammaglobulinemia with an increase in serum IgG. Two months postoperatively, the serum protein electrophoresis had returned to normal. Surface immunoglobulins (SIg) were determined on fresh cells in suspension using a polyvalent antiserum and monospecific antisera against heavy and light chains. Ten percent of the cells had SIg. The distribution of SIg-bearing cells was polyclonal. Intracytoplasmic immunoglobulin (CIg), as determined by immunofluorescence on ethanol-fixed smears from the cell suspensions, showed 6% positive cells. The distribution of cytoplasmic immunoglobulin was similarly polyclonal. Ethanol-fixed frozen sections also showed a polyclonal pattern when stained for CIg. Fifty-two percent of fresh cells in suspension formed Erosettes. These immunologic characteristics do not differ from those observed in non-neoplastic lymphoid tissues. A DNA content histogram was obtained by flow microfluorometry using ethanol-fixed cells stained with propidium iodide following RNase treatment. The DNA content distribution was within the normal limits established by the study of non-neoplastic lymphoid tissues.

Cytoplasm↗
PubMed1980

Percentage of cells in the S phase of the cell cycle in human lymphoma determined by flow cytometry.

The percentage of cells with S phase DNA content (S cells) was determined by flow cytometry in cell suspensions obtained from 27 patients with non-Hodgkin's lymphomas. DNA was measured in ethanol-fixed cells stained with propidium iodide after RNase treatment. Cells from 17 samples were also exposed to [3H]-thymidine and labeling indices were determined. An excellent linear correlation was observed between the percentage of S cells calculated by flow cytometry and the labeling index (r = 0.95). To determine the relationship between the percentage of S cells and the clinical behavior of the tumors, the survival of the 27 patients was analyzed. None of the patients was undergoing antineoplastic therapy at the time of the study. The patients were separated into 2 groups according to the percentage of S cells calculated by flow cytometry: those with less than 5% S cells and those with higher than 5% S cells. Clinical follow-up ranged from 5 to 20 months. While 7 of 12 patients with tumors containing more than 5% S cells have died of lymphoma (median survival, 9 months), there has been only one death from lymphoma among 15 patients with tumors containing less than 5% S cells. The difference in survival between these two groups is statistically significant (P = 0.01).

Autoradiography↗
PubMed1980

Flow analysis of DNA content and cell size in non-Hodgkin's lymphoma.

Cellular DNA content, Coulter volume, and light scatter were measured in cell suspensions from 30 non-Hodgkin's lymphomas in order to assess flow analysis as a quantitative and reproducible means of evaluating these diseases. Nonneoplastic control populations included 31 samples obtained from lymph nodes, spleens, tonsils, and peripheral blood. Cellular DNA and light scatter were measured on ethanol-fixed cells by flow microfluorometry using nuclei isolated from chicken erythrocytes as an internal standard. For DNA analysis, the cells were stained with propidium iodide following RNase treatment. The cellular DNA content of the human populations was expressed as a ratio between the DNA content of the human G0-G1 cells and that of the chicken erythrocyte nuclei. The mean DNA ratio for the 31 nonneoplastic samples was 2.83 +/- 0.08 (S.D.) In these samples, the coefficient of variation of the human G0-G1 peak ranged from 2.27 to 3.63% (mean 3.09 +/- 0.32%). Fifteen of 30 non-Hodgkin's lymphomas, including 7 of 15 low-grade lymphomas and 8 of 15 high-grade lymphomas, had abnormal DNA content, the majority containing hyperdiploid G0-G1 populations. In six malignant lymphomas with normal DNA content, the coefficient of variation of the human G0-G1 peak, corrected for differences in instrument setting was greater than that seen in the nonneoplastic populations. A good correlation between the percentage of cells calculated to be in the S phase of the cell cycle and the expected clinical behavior of the tumors was observed. In those lymphomas in which the S-phase percentages could be calculated, 11 of 13 low-grade lymphomas had less than 5% of the cells in S phase, and 7 of 10 high-grade lymphomas had greater than 5% of the cells in S phase. Thirteen of 21 neoplastic cases in which Coulter volume determinations were performed could be distinguished from the nonneoplastic controls on the basis of their modal volume. Although some correlation was observed between light scatter of ethanol-fixed cells and Coulter volume measurements on unfixed cells, light scatter was found to be less discriminatory. Altogether, by all three flow parameters studied, 26 of 30 (87%) of the neoplastic cases could be distinguished from nonneoplastic controls.

DNA Replication↗
PubMed1979

Cell surface markers on lymphoid cells from Warthin's tumors.

T- and B-cell markers were studied on suspensions of lymphoid cells obtained from two Warthin's tumors. Each tumor was composed predominantly of T- lymphocytes and a smaller percentage of B-lymphocytes with a polyclonal distribution of their surface immunoglobulin. These results do not differ from those obtained in normal or reactive lymph nodes. Together with the finding of normal lymph node structures in these tumors, our findings support the concept that the lymphoid component of Warthin's tumor represents pre-existing lymph node tissue.

Adenolymphoma↗
PubMed1978

Immunologic aspects and pathology of the malignant lymphomas.

Malignant lymphomas have traditionally been classified on solely morphologic grounds. With new immunologic and cytochemical techniques, it has been possible to characterize normal cells of the T-lymphocytic, B-lymphocytic, and monocyte-macrophage systems. Application of these methodologies to malignant lymphomas has established their nature as neoplasmas of the immune system. Within the B-lymphocytic system it is possible to identify subpopulations responsible for Burkitt's tumor, follicular (nodular) lymphomas, lymphocytic lymphomas of intermediate differentiation and well differentiated lymphocytic lymphomas. The T-lymphocytic system includes lymphoblastic lymphomas, mycosis fungoides, and Sezary's syndrome. Large cell lymphomas are diverse but the majority are tumors of transformed lymphocytes, usually of the B-lymphocytic system. The precise nature of the neoplastic cells of Hodgkin's disease, i.e., Reed-Sternberg cells and their mononuclear counterparts, has not yet been established. Despite previous suggestions of a B-lymphocytic or T-lymphocytic origin, recent studies utilizing in vivo cultivation have strongly suggested derivation from the monocyte-macrophage system.

Adolescent↗