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Biomedical subjects

T Godal

Publications and source records attributed to T Godal.

At least 73 records · Page 4Linked to original sources
PubMed1985

The specific induction of myc protooncogene expression in normal human B cells is not a sufficient event for acquisition of competence to proliferate.

Resting human B cells can be activated to proliferate in the presence of both polyclonal antibodies to immunoglobulin mu heavy chains and B-cell growth factor (BCGF). This process appears to be temporally controlled in that the initial activation of the B cells and their responsiveness to BCGF is carried out by polyclonal anti-mu-chain antibodies alone. We have used this system to investigate the role of the c-myc gene in the cell cycle of normal human peripheral blood B cells. Our results show that the polyclonal anti-mu-chain antibody-induced B-cell activation is accompanied by a specific induction of c-myc gene expression without promoting subsequent entry into the S phase unless BCGF is added. Monoclonal antibodies to either mu chain or the pan-B-cell antigen Bp35 also revealed a similar G0-to-G1 transition and activation of c-myc gene expression. However, unlike activation with polyclonal anti-mu-chain antibodies, cells stimulated with these monoclonal antibodies do not acquire responsiveness to BCGF. The results imply that additional inducible functions must be present to potentiate the myc-specific function in order for the B cells to acquire the capacity to proliferate in response to BCGF. These findings are discussed in relation to the origin of B-cell malignancies.

Antibodies, Anti-Idiotypic↗
PubMed1985

Characterization of two murine monoclonal antibodies reactive with human B cells. Their use in a high-yield, high-purity method for isolation of B cells and utilization of such cells in an assay for B-cell stimulating factor.

We describe two monoclonal antibodies, HH1 and HH2. Both reacted selectively with surface immunoglobulin (sIg)-positive human B cells. Both antibodies stained on average 7-8% of peripheral blood mononuclear cells. They have not been found to react with cells or cell lines of other haematopoietic cell lineages, except that HH2 was positive on a small percentage of cells of the erythroid cell line K562. The molecular weight of the HH1 antigen was 95 kD, as established by Western blotting. Neither of these two antibodies reacted with Ig determinants, Fc receptors, complement receptors, or known class-I or class-II molecules. A combination of these antibodies was used in a direct panning technique for high-yield enrichment of normal B lymphocytes from peripheral blood. The enriched B cells could be further purified by lysis of T cells (final yield, on average 72 +/- 8% of initial B cells) or by a second panning (yield, 35 +/- 11%). The purified B cells contained less than 1% contaminating T cells and less than 0.5% monocytes and were used in an assay for B-cell-stimulating factor which they showed a normal and very reproducible proliferative response.

Animals↗
PubMed1985

Distinct effects of gamma interferon on human B-lymphocyte precursor cell lines.

The effect of gamma interferon (IFN-gamma) on proliferation and antigenic characteristics of cell lines belonging to the B-cell progenitor compartment was studied. We observed a selective effect of recombinant IFN-gamma but not IFN-alpha on proliferation of the B-precursor cell lines Reh and KM3. On day 4, after addition of 400 mu/ml IFN-gamma the [3H]thymidine uptake in these cells was reduced to 60% and 45% respectively, while no effect of IFN-gamma was evident on the proliferation of the more mature B-cell lines Raji, Ramos, B85, and Daudi. On the other hand, both Reh and Ramos showed induction of major histocompatibility complex (MHC) class I antigen expression in response to 400 mu/ml IFN-gamma. In contrast to 12-O-tetradecanoyl-phorbol-13-acetate (TPA), IFN-gamma did not induce increased MHC class II antigen expression on Reh cells. Taken together, our results indicate that IFN-gamma fulfils distinct functions at different levels in the development of B cells.

B-Lymphocytes↗
PubMed1985

3H-thymidine uptake in B cell lymphomas--relationship to treatment response and survival.

Cell suspensions were obtained from biopsy tissue from 149 patients with B cell lymphomas and analysed with regard to DNA-synthesis as assessed by 3H-thymidine uptake, response to therapy and survival. The 3H-thymidine uptake was significantly increased in lymphomas of high versus low grade malignancy (p = 0.0001), in patients with stage I and II versus stage III and IV (p = 0.014), and in patients with general symptoms (p = 0.0025) as opposed to asymptomatic cases. The complete response rate was significantly higher in patients with increased thymidine uptake than in those with low uptake, 26/51 (51%) cases versus 24/83 (29%) cases, respectively (p = 0.014). 55 patients with increased 3H-thymidine uptake survived for significantly shorter times than (94 patients) with low uptake (p = 0.0056). Furthermore, a markedly larger group of high-risk patients was identified by the 3H-thymidine assay than by histopathology alone, 55 cases versus 23 cases, respectively. Among the patients (126 cases) with low grade tumours, those with increased 3H-thymidine uptake (40 cases) had poorer outcome than those with low uptake (86 cases) (p = 0.045). The data suggest that DNA-synthesis in this study, as assessed by 3H-thymidine uptake, is an independent indicator of survival in NHL. Furthermore, it may be a useful parameter in laying down guidelines for therapy in B cell neoplasms, especially in low grade tumours.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

Immunologic subsets in B cell lymphomas defined by surface immunoglobulin isotype and complement receptor--their relationship to survival.

Cell surface marker profiles were studied on cell suspensions from monoclonal B cell lymphomas. Surface immunoglobulin (sIg) was examined in 178 cases, whereas combined data with sIg and receptors for complement (C3) were available in 99/178 cases. The results showed that B cell lymphomas can be divided into distinct immunological subsets according to surface marker expression. Whereas some histologic subgroups (diffuse centroblastic/centrocytic, centrocytic, immunocytoma) (Kiel classification) consisted of few immunological subtypes, others were more heterogeneous (follicular centroblastic/centrocytic, centroblastic, lymphocytic). By combining immunological and histological subgroups, more than 40 phenotypes could be identified; this diversity most likely reflects, the heterogeneity of the B cell compartment. As part of the same study the prognostic significance of cell marker phenotypes was examined. Survival analysis undertaken on 149/178 patients did not uncover any significant relationship between type of heavy or light chain expression, C3 receptor expression and clinical outcome. Our data do not confirm recent findings that the type of immunological phenotype may be of prognostic significance.

Aged↗
PubMed1985

No correlation between membrane potential and increased cytosolic free Ca2+ concentration, 86Rb+ influx or subsequent [3H]-thymidine incorporation in neoplastic human B cells stimulated with antibodies to surface immunoglobulin.

We have followed the changes in the membrane potential of neoplastic B cells after addition of antibodies to cell specific surface immunoglobulin heavy chains (anti-Ig). Two methods were used, both based on the distribution of lipophilic fluorescent indicators: the anionic bis(1,3-diethylthiobarbiturate)-trimethine oxonol (fluorescence measurement made on whole cell suspensions) and the cationic 3,3-dihexyloxacarbocyanine iodide (diOC6-(3] (using flow cytofluorimetric analysis). By the latter method, the resting membrane potential was calculated to range from -40 to -63 mV. The stimulatory effect of anti-Ig was investigated on two B cell populations. In one, which may be stimulated in this way to [3H]-thymidine incorporation, the membrane potential was apparently unchanged, at least during the first hour of stimulation. In the other population, anti-Ig induced a rapid depolarization (oxonol method), but these cells did not, on the other hand, respond with [3H]-thymidine incorporation. The nature of this depolarization was further investigated. Both Na+ and K+ permeabilities appeared increased, while Ca2+ influx did not contribute to the change in membrane potential. Nor did depolarization itself change free cytosolic Ca+ concentration, [Ca2+]i, as estimated by the quin-2 method. Furthermore, anti-Ig stimulation increased [Ca2+]i in these cells, even when depolarization was abolished by lowering the extracellular Na+ concentration. Thus, in cells where depolarization could be demonstrated, it was linked neither to early changes in [Ca2+]i nor to late [3H]-thymidine incorporation. In contrast, such effects of anti-Ig stimulation were observed in other cells without any significant early change in the membrane potential.

Antibodies↗
PubMed1985

Intracellular Ca2+ buffering potentiates an 86Rb+ permeability response in human lymphocytes.

The effects of antibodies against immunoglobulin delta-heavy chains (anti-delta) on intracellular free Ca2+ concentrations, [Ca2+]i, and 86Rb+ influx in human neoplastic B-cells were tested in vitro. When preloading the cells with high concentrations of the fluorescent Ca2+ chelator quin 2 and subsequently stimulating in EGTA medium, the anti-delta induced rise in [Ca2+]i was strongly reduced or blocked. Nevertheless, 86Rb+ influx, also induced by anti-delta, was potentiated. In fact, in a population of cells in which anti-delta increased [Ca2+]i, but not 86Rb+ influx under standard conditions, the combination of quin-2 preloading and subsequent extracellular Ca2+ chelation by EGTA revealed an anti-delta induced 86Rb+ influx. Most of this influx was ouabain resistant, suggesting only a minor contribution from the Na+/K+ pump. Based on the Ca2+ buffer effect of quin 2 we suggest that the Ca2+ effect on 86Rb+ (K+ analogue) permeability is not mediated by increased [Ca2+]i but rather by the Ca2+ release per se from the plasma membrane.

Antibodies↗
PubMed1985

BCG-induced suppressor T cells optimal conditions for in vitro induction and mode of action.

In vitro activation with BCG of T cells from healthy individuals vaccinated with BCG lead to the induction of suppressor cells that suppressed the proliferation of fresh T cells in response to specific antigen. Kinetics of their induction revealed that they became radioresistant by day 8 and persisted up to 18 days of the culture period. Optimal antigen and monocyte concentrations as assessed by proliferation during the induction phase also resulted in maximum suppression. The strongest suppressor activity was observed when suppressor cells were added at an early time of fresh cell activation. IL-1 production from adherent cells in response to BCG was not affected, but, IL-2 production by T-cells was considerably reduced in the presence of suppressor cells. IL-1 containing supernatants and affinity purified IL-1 exogenously added to the culture system did not affect suppression. Whereas, recombinant IL-2 partially abrogated suppression in a dose-dependent manner. Further experiments suggested that suppressor cells might have inhibited BCG induced IL-2 receptor expression on fresh T cells.

Antigens, Bacterial↗
PubMed1985

In vivo responses to Mycobacterium leprae: antigen presentation, interleukin-2 production, and immune cell phenotypes in naturally occurring leprosy lesions.

To investigate the immune defect in lepromatous leprosy we studied immune cell phenotypes, lymphocyte activation states, and interleukin-2 (IL-2) production in naturally occurring leprosy skin lesions. Mouse hybridoma monoclonal antibodies reacting with the IL-2 receptor (anti-Tac), unbound IL-2 (DMS-1), antigen-presenting Langerhans' cells (OKT6) and the OKT4-Leu3 and OKT8 T-lymphocyte subpopulations were used with indirect horseradish peroxidase and alkaline phosphatase techniques on frozen biopsy sections. The percentage of Tac+ lymphocytes and the number of OKT6+ cells in the epidermis and dermal granuloma were significantly correlated in naturally occurring lesions (correlation coefficient 0.79) and were higher in tuberculoid than in lepromatous lesions. Leu3 antigen was expressed by 70-90% of Tac+ cells in tuberculoid lesions. Although the percentage of cells producing IL-2 was low in lesions of both lepromatous and tuberculoid patients, it was about 15 times greater in tuberculoid than in lepromatous lesions (0.032 +/- 0.037 tuberculoid vs 0.0019 +/- 0.023 lepromatous). There was an association between the number of OKT6+ cells and the percentage of IL-2-producing cells, but the association was weaker than that of OKT6+ cells and the percentage of IL-2 receptor-bearing cells (r = 0.2), implying that IL-2 production is not an intervening variable in the latter association. The absolute number of OKT4-Leu3+ lymphocytes was significantly different in different clinical leprosy groups and was positively correlated with host resistance (mean OKT4-Leu3+ cells/mm2 in 6 micron sections; 1412 +/- 288 tuberculoid, 400 +/- 93 borderline lepromatous, 200 +/- 100 polar lepromatous; r = 0.95). Absolute numbers of OKT8+ cells/mm2 in lesions were not significantly different. We conclude that there is a relative paucity of OKT4-Leu3+ cells as well as IL-2-producing cells at the local level in lepromatous leprosy lesions. Possible functional relationships between these findings and the failure of macrophage activation and destruction of Mycobacterium leprae in lepromatous leprosy are discussed.

Adolescent↗
PubMed1985

Differences in modifications of cytoplasmic free Ca2+ concentration and 86Rb+ influx in human neoplastic B cells by antibodies to mu- relative to delta-Ig heavy chains.

Cytoplasmic free Ca2+ concentration and influx of 86Rb+ (K+ analogue) were determined during the first minutes after stimulation of neoplastic human B cells and B cell lines by antibodies to surface Ig. The Ca2+ concentration increased in the great majority of samples (41 of 48). All of four B cell lines also responded, providing formal evidence that accessory cells are not required for this early, surface Ig-mediated event. Antibodies to delta as well as mu, heavy chains (anti-delta and anti-mu) could induce both Ca2+ and 86Rb+ responses. 86Rb+ responders were found within the group of Ca2+ responders, but no quantitative relation was observed between the two responses. In cells expressing both sIgM and sIgD, antibodies to delta heavy chains were more potent than those to mu heavy chains in inducing Ca2+ responses, whereas the opposite pattern was seen with regard to 86Rb+ responses. These results demonstrate that sIgM and sIgD can deliver different biochemical signals to the cell.

Antibodies, Neoplasm↗
PubMed1984

Transferrin receptor and B-lymphoblast antigen--their relationship to DNA synthesis, histology and survival in B-cell lymphomas.

The reactivity of two monoclonal antibodies identifying antigens related to B-cell activation, B3/25 (the transferrin receptor) and BB-I (the B-lymphoblast-I-antigen), was examined on cell suspensions from 75 cases of monoclonal B-cell lymphomas. The expression of B3/25 antigen was correlated to DNA synthesis as measured by spontaneous 3H-thymidine incorporation (p = 0.0003) and histopathologically high-grade malignancy (p = 0.00003). Furthermore, B3/25 expression was associated with survival since the patients with B3/25-negative tumors survived longer than those with B3/25-positive tumors (p = 0.018). B3/25 expression also defined a larger group of patients with shorter survival than did histopathology alone, 28 cases versus 16 cases, respectively. On the other hand, the BB-I antigen did not reveal an association with DNA synthesis, high-grade malignancy or survival. However, the findings indicated that BB-I may be related to B-cell maturation/differentiation.

Antibodies, Monoclonal↗
PubMed1984

Epstein-Barr virus binding to virus-carrying cell lines is enhanced in the presence of C3 and C3d.

The relationship between the receptors for the Epstein-Barr virus (EBV) and the C3d fragment of complement was investigated at the molecular level. In the presence of cell-bound C3, virus binding was enhanced in EBV genome-carrying lines. An identical effect could be elicited by C3d at one-quarter the weight amount; C3b and methylamine-treated C3 had no effect on virus binding. The minimum concentration of C3 which produced significant enhancement was 25 micrograms/ml. Virus binding increases were observed only after 20 min of complement-cell co-incubation. The response was not noted with EBV-negative lines and was independent of virus strain assayed (B95-8 and P3HR-1). These studies suggest that the binding sites for the two moieties are distinct, although they both involve the same cell surface complex. The two receptors are believed to display cooperativity.

Cell Line↗
PubMed1984

Different fate of antibodies to surface IgM and IgD in germinal centre cell-associated lymphomas.

In all of four human germinal centre cell-associated B lymphomas carrying sIgM + sIgD F(ab')2 fragments of rabbit antibodies to human mu-chain were accumulated intracellularly, whereas the accumulation of antibodies to delta-chain was considerably less abundant. The accumulation of antibodies to light chain was intermediate between antibodies to mu- and delta-chain. These results could be explained by the following observations: (i) the difference in the level of reexpression of sIgM and sIgD and (ii) the discovery that antibodies to delta-chain bound to reexpressed sIgD were degraded at a higher rate than those bound to primary sIgD and at a higher rate than antibodies to mu-chain, whether bound to primary or reexpressed sIgM.

Absorption↗
PubMed1984

Induction of maturation in different types of B-cell lymphomas in vitro with TPA and antibodies to surface immunoglobulin.

Cells from eight selected cases of human non-Hodgkin lymphomas of various histological types (lymphocytic, centrocytic, centrocytic/centroblastic, and immunocytomas) were stimulated in vitro with 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and anti-immunoglobulins (anti-Ig) against the surface immunoglobulin (sIg) on the tumour cells. Six of these cases responded by intracellular Ig accumulation as measured by flow cytofluorometry and direct phenotypical change into immunoblasts/plasmablasts as detected by light microscopic immunocytochemistry. However, the response to TPA alone varied considerably from case to case. These findings suggest that many, if not all, B-cell subsets have the capacity to develop directly into Ig-synthesizing cells (immunoblasts and plasmablasts). However, conditions for eliciting such events may vary, depending on the phenotypical properties and differentiation stage.

Antibodies, Anti-Idiotypic↗
PubMed1984

The great majority of childhood lymphoblastic leukaemias are identified by monoclonal antibodies as neoplasias of the B-cell progenitor compartment.

36 acute leukaemias in children, 24 lymphoblastic and 14 myelogenous, have been examined with a set of 10 monoclonal antibodies by indirect fluorescent staining. In the lymphoblastic group the leukaemic cells of 4 children were found to have T-cell phenotype, while 19 of the other 20 T-cell phenotype negative cases were found to be positive for the c-ALL antigen. All 20 were negative for surface immunoglobulin as well as cytoplasmic mu-heavy chains. However, 17 (85%) reacted positively with the monoclonal antibody AB-1 which we have developed against a B-cell lymphoma, thus revealing B-lineage specificity. Another B-lineage-associated antibody (AB-2) reacted with 8/20 (40%) of the cases with distribution similar to B-1. These findings suggest that the great majority of non-T-non-B acute lymphoblastic leukaemias are neoplasms derived from the B-cell progenitor compartment. Moreover, monoclonal antibody testing allows further sub-categorization in this group. Similarly the acute-myelogenous leukaemia group could be subdivided into phenotypic subsets. The importance of using panels of monoclonal antibodies in the diagnosis of acute leukaemias is discussed.

Adolescent↗
PubMed1984

Reversal by interleukin-2 of the T cell unresponsiveness of lepromatous leprosy to Mycobacterium leprae.

In some subjects Mycobacterium leprae causes disseminated (lepromatous) disease. Such subjects show both in vivo and in vitro deficient T cell responses to M. leprae, but not to other antigens. We have recently shown that lepromatous peripheral blood mononuclear cells (PBMC) failed to produce interleukin 2 (IL-2) in response to M. leprae and that T cell-conditioned media (TCM) can reverse the T cell unresponsiveness in a majority of lepromatous leprosy patients (Haregewoin et al. 1983). Here we show that highly purified and recombinant IL-2 had effects similar to TCM. On the other hand, lepromatous PBMC produced IL-1, and IL-1 had no restorative effect. These findings provide further evidence that the unresponsiveness in lepromatous leprosy often results from a deficiency in IL-2 production. After initial stimulation with TCM + M. leprae, lepromatous PBMC could be restimulated with M. leprae alone, providing clear evidence that M. leprae-reactive lymphocytes were generated in the presence of TCM. The present findings are discussed in relation to the possible mechanisms involved in the failure of IL-2 production. If our findings can be reproduced in vivo, IL-2 may offer a novel approach to therapy in lepromatous leprosy.

Antigens, Bacterial↗