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53. Effect of concanavalin A on human T cell subpopulations
American
Acaclemy of Allergy
2. ALLERGY CLIN. IMMUNGL. MARCH 1978
control subjects were stimulated with varying doses of mitogen at day 0 and titer 24 hr of preculture. In this system, increased proliferative response of precultured cells as compared with O-hr cells has previously been shown in normal subjects to represent loss of SC function in vitro. The lack of such an increase implies aberrant SC function. The data from the first assay showed no significant difference in con A-act SC function in AD patients when compared with that of control subjects (mean suppression, 23.8% ?I 3 vs 25.5% AT 2.8, p > 0.2.). In the second assay, 24-hr precultured cells of AD patients and control subjects both showed an increased proliferative response to mitogen when compared with respective 0-hr cultures, e .g . , ACFMZd/ACPMO, 5.4 2 1.3 vs 5.9 ? 0.9, p > 0.1. Thus, suppressor cell function as tested in these proliferative assays, appears normal in A.D patients with increased IgE.
. aas muno
ific suppression of in synthesis and secretion.
Stanley A. Schwartz, M.D., Ph.D., and Robert CZOQ~, M.D, Ph.D., New York, N. Y.
A.
Suppressor cells capable of inhibiting all classes of immunoglobulin (Ig) synthesis and secretion have been demonstrated in the peripheral blood of immunodeficient patients with hypogammaglobulinemia, Peripheral blood lymphocytes (PBL) from patients with selective deficiency of IgA were examined for the capacity to synthesize and secrete IgG, IgM, and IgA in vitro in response to polyclonal B cell activation with pokeweed mitogen (PWM). Ig was measured in the supematants of cultures stimulated with 10 @g/ml of PWM for 7 days by means of a fluorescent, solid state, heavy chain-specific immunoassay. The in vitro B cell activity tended to parallel the clinical status, that is, PBL from patients with selective IgA deficiency were capable of synthesizing and secreting IgG and IgM in response to stimulation with PWM but were unable to produce appreciable amounts of IgA. Coculture experiments with the use of PBL from patients with selective IgA deficiency and normal donors yielded several different immunoregulatory effects including helper activities directed toward the synthesis and secretion of IgG and IgM. However, specific suppression of only IgA synthesis and secretion was obseived in several cocultures containing PBL from patients with selective IgA deficiency. These results suggest that selective IgA deliciency may be a heterogeneous syndrome and s~~pport a model for Ig class-specific suppressor cells in the pathogenesis of some cases of selective IgA deficiency.
3 Effect of concanavalin A on human celi su~p~~uiatio~s. Sudhir Gupta, M.D.,
T
F.R.C.P.[CjJ Stanley A. Schwartz, M.D., Ph,D., and obert A. Good, M.D., Ph.D., New York, N. Y. Concanavalin A (con A) treatment of peripheral blood lymphocytes generates suppressor activity for T and B cell responses. However, the precise mechanism of such induced suppression is not known. We have investigated the effect of con A treatment on two distinct subpopulations of
human T lymphocytes, that is, T cells with receptors for ,IgM (Tp) and for IgG (Ty). Tp cells contain helper activity and Ty cells have suppressor activity for the differentiation of B cells into plasma cells. Lymphocytes were incubated with neuraminidase-treated sheep erythrocytes. T cells were purified by separating rosetting cells,from nonrosetting cells on Ficoll-Hypaclue density gradient. Purified T cells were incubated with varying concentrations (2.5, 5, 10, 20, and 40 pg/ml) of con A and examined for the proportions of Tp and T-y cells. T,u and Ty cells were assayed by rosette technique with the use of ox erythrocytes coated with IgM and IgG antibody, respectively. At 2.5 pg/ml con A, there was a significant increase in the proportions of Tp cells. No effect was observed on Ty cells. At a concentration of 40 Fg/ml of con A a significant reduction in the proportions of Tp cells and significant increase in the proportion of Ty cells was observed, At the intermediate concentrations of con A enhancement of Ty cells alone was observed. This study clearly indicates that con A at low concentrations induces helper effect by increasing the numbers of Tp cells. At high concentrations suppressor effect appears to be secondary to both the decrease in Tp cells and increase in Ty cells.
54. Histamine-induced supp (HSF): Nature of stimulus an Rockiin, Boston,
M.D., and Dirk Greineder, Mass.
M.5.,
Lymphocytes exposed to histamme in vitro produce a soluble factor (25 to 40 K), HSF, which suppresses migration inhibition factor (MIF) production and proliferation by immune guinea pig lymph node cells (LNC). (Rocklin, R.E.: J. Immunol. 118:1734, 1977.) The present studies examined the lymphocyte subpopulation which produces it, the nature of the stimulus, and its effect on various strains of guinea pig LNC. Hartley LNC were purified into T cell +95%) and B cell (>90%) subpopulations by passage over nylon wool and EAC rosetting and then assayed for their ability to make HSF. T cells, but not B cells (or macrophages), made HSF. We next investigated whether other allergic mediators could induce lymphocytes to produce HSF. Prostaglandin E1 (lo-* M), serotonin (low3 M), ECF-A ( 10m6 M), and SRS-A (lo-* M) were incubated with lymphocytes and the cell-free supematants assayed for HSF-like activity. None of the above mediators induced the formation of a suppressive supematant. Thus> among the allergic mediators, histamine seems to be unique in this regard. We showed previously that Ht-receptor (but not Hi-receptor) antagonists could block HSF production. The specific type of histamine receptor involved was confirmed here by the use of H1 (2-methylhistamine) and HZ (4methylhistamine) agonists. Only the HZ (but not the HI) agonist was capable of stimulating lymphocytes to make HSF. In other experiments, HSF was made in different guinea pig strains (Hartley, strain 2, strain 13) and assayed for its effect on autologous and homologous strain LNC. The results indicate that the effect of HSF on MIF production is not strain specific.
Acaclemy of Allergy
2. ALLERGY CLIN. IMMUNGL. MARCH 1978
control subjects were stimulated with varying doses of mitogen at day 0 and titer 24 hr of preculture. In this system, increased proliferative response of precultured cells as compared with O-hr cells has previously been shown in normal subjects to represent loss of SC function in vitro. The lack of such an increase implies aberrant SC function. The data from the first assay showed no significant difference in con A-act SC function in AD patients when compared with that of control subjects (mean suppression, 23.8% ?I 3 vs 25.5% AT 2.8, p > 0.2.). In the second assay, 24-hr precultured cells of AD patients and control subjects both showed an increased proliferative response to mitogen when compared with respective 0-hr cultures, e .g . , ACFMZd/ACPMO, 5.4 2 1.3 vs 5.9 ? 0.9, p > 0.1. Thus, suppressor cell function as tested in these proliferative assays, appears normal in A.D patients with increased IgE.
. aas muno
ific suppression of in synthesis and secretion.
Stanley A. Schwartz, M.D., Ph.D., and Robert CZOQ~, M.D, Ph.D., New York, N. Y.
A.
Suppressor cells capable of inhibiting all classes of immunoglobulin (Ig) synthesis and secretion have been demonstrated in the peripheral blood of immunodeficient patients with hypogammaglobulinemia, Peripheral blood lymphocytes (PBL) from patients with selective deficiency of IgA were examined for the capacity to synthesize and secrete IgG, IgM, and IgA in vitro in response to polyclonal B cell activation with pokeweed mitogen (PWM). Ig was measured in the supematants of cultures stimulated with 10 @g/ml of PWM for 7 days by means of a fluorescent, solid state, heavy chain-specific immunoassay. The in vitro B cell activity tended to parallel the clinical status, that is, PBL from patients with selective IgA deficiency were capable of synthesizing and secreting IgG and IgM in response to stimulation with PWM but were unable to produce appreciable amounts of IgA. Coculture experiments with the use of PBL from patients with selective IgA deficiency and normal donors yielded several different immunoregulatory effects including helper activities directed toward the synthesis and secretion of IgG and IgM. However, specific suppression of only IgA synthesis and secretion was obseived in several cocultures containing PBL from patients with selective IgA deficiency. These results suggest that selective IgA deliciency may be a heterogeneous syndrome and s~~pport a model for Ig class-specific suppressor cells in the pathogenesis of some cases of selective IgA deficiency.
3 Effect of concanavalin A on human celi su~p~~uiatio~s. Sudhir Gupta, M.D.,
T
F.R.C.P.[CjJ Stanley A. Schwartz, M.D., Ph,D., and obert A. Good, M.D., Ph.D., New York, N. Y. Concanavalin A (con A) treatment of peripheral blood lymphocytes generates suppressor activity for T and B cell responses. However, the precise mechanism of such induced suppression is not known. We have investigated the effect of con A treatment on two distinct subpopulations of
human T lymphocytes, that is, T cells with receptors for ,IgM (Tp) and for IgG (Ty). Tp cells contain helper activity and Ty cells have suppressor activity for the differentiation of B cells into plasma cells. Lymphocytes were incubated with neuraminidase-treated sheep erythrocytes. T cells were purified by separating rosetting cells,from nonrosetting cells on Ficoll-Hypaclue density gradient. Purified T cells were incubated with varying concentrations (2.5, 5, 10, 20, and 40 pg/ml) of con A and examined for the proportions of Tp and T-y cells. T,u and Ty cells were assayed by rosette technique with the use of ox erythrocytes coated with IgM and IgG antibody, respectively. At 2.5 pg/ml con A, there was a significant increase in the proportions of Tp cells. No effect was observed on Ty cells. At a concentration of 40 Fg/ml of con A a significant reduction in the proportions of Tp cells and significant increase in the proportion of Ty cells was observed, At the intermediate concentrations of con A enhancement of Ty cells alone was observed. This study clearly indicates that con A at low concentrations induces helper effect by increasing the numbers of Tp cells. At high concentrations suppressor effect appears to be secondary to both the decrease in Tp cells and increase in Ty cells.
54. Histamine-induced supp (HSF): Nature of stimulus an Rockiin, Boston,
M.D., and Dirk Greineder, Mass.
M.5.,
Lymphocytes exposed to histamme in vitro produce a soluble factor (25 to 40 K), HSF, which suppresses migration inhibition factor (MIF) production and proliferation by immune guinea pig lymph node cells (LNC). (Rocklin, R.E.: J. Immunol. 118:1734, 1977.) The present studies examined the lymphocyte subpopulation which produces it, the nature of the stimulus, and its effect on various strains of guinea pig LNC. Hartley LNC were purified into T cell +95%) and B cell (>90%) subpopulations by passage over nylon wool and EAC rosetting and then assayed for their ability to make HSF. T cells, but not B cells (or macrophages), made HSF. We next investigated whether other allergic mediators could induce lymphocytes to produce HSF. Prostaglandin E1 (lo-* M), serotonin (low3 M), ECF-A ( 10m6 M), and SRS-A (lo-* M) were incubated with lymphocytes and the cell-free supematants assayed for HSF-like activity. None of the above mediators induced the formation of a suppressive supematant. Thus> among the allergic mediators, histamine seems to be unique in this regard. We showed previously that Ht-receptor (but not Hi-receptor) antagonists could block HSF production. The specific type of histamine receptor involved was confirmed here by the use of H1 (2-methylhistamine) and HZ (4methylhistamine) agonists. Only the HZ (but not the HI) agonist was capable of stimulating lymphocytes to make HSF. In other experiments, HSF was made in different guinea pig strains (Hartley, strain 2, strain 13) and assayed for its effect on autologous and homologous strain LNC. The results indicate that the effect of HSF on MIF production is not strain specific.