concanavalin-a and Sjogren-s-Syndrome

To assess ex vivo CD4(+) T-cell cytokine expression from patients with primary Sjögren's syndrome (SS) following in vitro stimulation to induce proliferation, as proliferation is closely related to differentiation of cytokine-producing cells.. Peripheral blood mononuclear cells (PBMCs) separated from primary SS patients (n = 28) and controls (n = 25) were analysed. PBMCs were stimulated with concanavalin A followed by phorbol 12-myristate 13-acetate and ionomycin. Intracellular interferon-gamma (IFN-gamma) and interleukin-4 (IL)-4 in proliferating CD4(+) T cells were assessed by flow cytometry. The proportion of cytokine-producing cells and proliferating cells in each division cycle was assessed using [5(and 6)-carboxyfluorescein diacetate, succinimidyl ester]-labelled CD4(+/-) T cells.. The proportion of IFN-gamma+ proliferating CD4(+) T cells in each cell division cycle from extraglandular SS was increased in glandular SS patients compared glandular SS patients with controls (P<0.05 approximately 0.01). The percentage of IFN-gamma single positive proliferating CD4(+) T cells was greater in extraglandular SS patients (26.7+/-14.1%) compared with glandular SS (9.9 +/- 9.1%) (P<0.01) and controls (9.4 +/- 5.8%) (P<0.001). There was no significant difference in the percentages of IL-4(+) proliferating CD4(+) T cells among the groups. However, the proliferating response of CD4(+) T cells was significantly decreased in extraglandular SS patients (percentage of proliferating cells 38.4 +/- 18.6%) compared with that in glandular SS patients (64.2 +/- 17.2%) (P<0.05) and controls (63.1+/-10.6%) (P<0.01).. CD4(+) T cells from extraglandular SS patients may have a predisposition for entry into the IFN-gamma-producing effector pathway as a result of the stimulations. These results are helpful for understanding the immunological difference between glandular and extraglandular SS and the mechanisms of disease progression.

Topics: Adult; CD4-Positive T-Lymphocytes; Cell Division; Cells, Cultured; Concanavalin A; Cytokines; Female; Flow Cytometry; Humans; Interferon-gamma; Interleukin-4; Ionomycin; Ionophores; Leukocytes, Mononuclear; Male; Middle Aged; Mitogens; Sjogren's Syndrome; Tetradecanoylphorbol Acetate

To determine whether chronic exposure to lymphocyte-derived cytokines could inhibit the fluid secretory mechanism in salivary gland acinar cells and so account for the loss of gland function seen in the early stages of Sjögren's syndrome.. Mouse submandibular acinar cells maintained in primary culture were exposed to a profile of cytokines produced by concanavalin A-activated splenic lymphocytes in vitro for periods up to 72 h. Agonist-evoked changes in intracellular Ca(2+) were determined microfluorimetrically in both control and cytokine-treated cells.. Acinar cells maintained in primary culture in the presence of cytokines for up to 72 h were able to mobilize intracellular calcium in response to stimulus by acetylcholine in an identical fashion to those maintained in primary culture in the absence of cytokines. Acute application of the conditioned medium produced by the activated lymphocytes had an antisecretory effect on acetylcholine-evoked Ca(2+) mobilization, which was found to be mediated by cholinesterase rather than by cytokines.. Neither chronic nor acute exposure to the profile of cytokines released by concanavalin A-activated splenic lymphocytes interfered in any way with the second messenger cascade and fluid and electrolyte secretion in acinar cells. Our data suggest an alternative hypothesis, in which elevated levels of cholinesterase can metabolize acetylcholine released within the salivary glands and thus prevent fluid secretion.

Topics: Acetylcholine; Animals; Calcium; Carbachol; Cells, Cultured; Cholinergic Agonists; Concanavalin A; Culture Media, Conditioned; Enzyme Inhibitors; Interferon-gamma; Interleukin-2; Interleukin-3; Interleukin-4; Interleukin-6; Lymphocytes; Male; Mice; Mice, Inbred Strains; Saliva; Sjogren's Syndrome; Spleen; Submandibular Gland; Thapsigargin; Vasodilator Agents

A strong increase of the affinity for concanavalin A (Con A) of serum alpha 2-macroglobulin, a non-acute-phase protein, was observed by lectin blotting in patients with Sjögren's syndrome (SS). On the contrary, the total Con A reactivity of serum proteins, measured by enzyme-linked lectin assay, was not augmented in SS, compared with normal donors, probably because positive changes of certain proteins were balanced by negative changes of others, as suggested by lectin blotting analysis. However, a significant increase of total Con A reactivity occurred in subjects with increased serum concentrations of soluble interleukin (IL)-2 receptor, compared with patients with normal concentrations of this marker of disease activity. On the other hand, the same parameter did not appear to be different in patients with normal or increased serum concentrations of IL-6, indicating that this cytokine was not probably responsible for the changes of glycosylation described here.

Topics: Adult; Aged; alpha-Macroglobulins; Blood Proteins; Concanavalin A; Enzyme-Linked Immunosorbent Assay; Female; Glycosylation; Humans; Interleukin-6; Male; Middle Aged; Receptors, Interleukin-6; Sjogren's Syndrome

To clarify possible associations of decay-accelerating factor (DAF, CD55), expressed on circulating lymphocyte subsets and other hematologic cells, with corresponding cytopenias observed in primary Sjögren's syndrome (SS).. DAF expression on peripheral blood (PB) cells was determined in 21 patients with SS and 11 healthy controls by single or 2 color flow cytometry.. In the PB from SS patients, anemia, monocytopenia, neutropenia, and lymphocytopenia were observed. Compared to the controls, the percentages of DAF-negative cells were higher in CD4+ and CD8+ T cell subsets from SS patients, but the expression of DAF was similar in the other PB cells, including CD19+ B cells, CD56+ NK cells, monocytes, granulocytes, and erythrocytes. The percentages of DAF-negative cells among the CD4+ and CD8+ cells were positively correlated in SS patients, but the numbers of cells in both subsets were decreased in those patients being treated with prednisolone. However, these proportional changes are thought to reflect a decrease in the numbers of DAF-positive CD4+ and CD8+ cells, because the absolute numbers of circulating DAF-positive CD4+ and CD8+ cells, but not DAF-negative cells, were significantly decreased in SS patients. In addition, DAF-negative cells were detectable in both CD45RA+ (naive) and CD45RO+ (memory) T cells from healthy individuals, and the expression of DAF was remarkably increased in both subsets after in-vitro activation with concanavalin-A.. DAF-negative cells are proportionally increased among circulating CD4+ and CD8+ T cells in SS patients, although such changes are due to decreased numbers of DAF-positive cells within each subset. When considering previous observations, the DAF-negative CD4+ and CD8+ cells probably belong to activated T cell subsets in both SS patients and controls. However, the patterns of DAF expression seemed to be different between activated T cells recognized in the PB, and those induced by in vitro-stimulation.

Topics: Adult; Aged; CD4-Positive T-Lymphocytes; CD55 Antigens; CD8-Positive T-Lymphocytes; Cells, Cultured; Concanavalin A; Female; Humans; Lymphocyte Activation; Lymphocyte Count; Male; Middle Aged; Sjogren's Syndrome

We investigated serum levels of interleukin-6 (IL-6), interferon-gamma (IFN-gamma), and tumor necrosis factor alpha (TNF alpha) from patients with systemic lupus erythematosus (SLE) and its various clinical manifestations of disease and from patients with rheumatoid arthritis (RA) and other rheumatic diseases. The serum levels of IL-6 and IFN-gamma were highly elevated from patients with SLE associated with lymphadenopathy (LN) or nephrotic syndrome (NS). On the contrary, the serum levels of TNF alpha were elevated from most patients with SLE associated with thrombocytopenia (TP). However, serum levels of TNF alpha were in the normal range from patients with SLE associated with NS, LN, or central nervous system disease. Of interest, patients with SLE associated with humoral immunodeficiency disorder, hypogammaglobulinemia, had highly elevated levels of serum IL-6. The concanavalin A-stimulated mononuclear cells (MNC) of patients with SLE associated with TP secreted highly elevated levels of TNF alpha compared to other patient groups. We suggest that abnormal production of various cytokines in SLE is an intrinsic defect of MNC and the immune system that may be the key element for a variety of clinical manifestations of this disease.

Topics: Adolescent; Adult; Arthritis, Rheumatoid; Behcet Syndrome; Concanavalin A; Cytokines; Female; Humans; Interferon-gamma; Interleukin-6; Lupus Erythematosus, Systemic; Lymphadenitis; Male; Middle Aged; Nephrotic Syndrome; Polymyalgia Rheumatica; Rheumatic Diseases; Sjogren's Syndrome; Thrombocytopenia; Tumor Necrosis Factor-alpha

Lymphocyte subsets in the peripheral blood of 18 patients with Sjogren's syndrome (SS) were studied using monoclonal antibodies and the fluorescence-activated cell sorter (FACS). The percentage of T cells was decreased when compared to normal controls. In primary SS, there was a proportional decrease in both suppressor/cytotoxic (anti-Leu-2a reactive) and helper/inducer (anti-Leu-3a reactive) T cells with an unchanged helper/suppressor ratio (1.8 vs. 1.7 for normals). In SS with an associated connective tissue disorder, there was a significant decrease only in the suppressor/cytotoxic subset. There was increase in B cells and null cells in primary SS compared to controls. Quantitative immunofluorescence allowed the calculation of determinant density per cell. Cells expressing low antigen density Leu-2a were increased in 8 patients (4 with primary SS and 4 with SS with an associated disorder). Thus, in addition to quantitative changes in lymphocyte subsets, we found changes in Leu-2a expression suggesting abnormal differentiation of the suppressor/cytotoxic subset. These changes may contribute to the immunoregulatory disturbance in Sjogren's syndrome.

Topics: Adult; Aged; Animals; Antibodies, Monoclonal; Cell Separation; Concanavalin A; Female; Flow Cytometry; Goats; Histocompatibility Antigens Class II; HLA-DR Antigens; Humans; Lymphocyte Activation; Lymphocytes; Male; Middle Aged; Phytohemagglutinins; Pokeweed Mitogens; Sjogren's Syndrome; T-Lymphocytes

21 patients with Sjögren's syndrome (sicca syndrome) with either glandular or extraglandular involvement, but without other connective tissue diseases, were studied with regard to immunoregulatory T-cell subpopulations, B-cell function, and suppressor cell capabilities. Patients with isolated glandular disease as well as patients with extraglandular disease had normal absolute numbers of total lymphocytes, T cells, and B cells. However, 9 of 11 patients with extraglandular disease and only 3 of 10 patients with glandular disease had decreased relative proportions of T cells bearing receptors for the Fc portion of immunoglobulin (Ig)G (T(G)) which was explained by a factor that blocked the expression of the IgG Fc receptor on T(G) cells. This blockage was reversible since the factor could be removed by trypsinizing the T cells before T(G) determination. Serum from patients with abnormal proportions of T(G) cells, but not serum from patients with normal proportions of T(G) cells, blocked the expression of the IgG Fc receptor on normal T cells. The serum factor upon fractionation over Bio-Gel A 1.5 columns as well as over staphylococcal protein A-Sepharose 4B columns was found diffusely within the IgG fraction, and not in the IgM fraction. Neither patients with glandular nor patients with extraglandular disease manifested increased numbers of in vivo-activated circulating lymphocytes as determined by spontaneous anti-trinitrophenyl (TNP) plaque-forming cells (PFC). However, patients with glandular disease had reduced numbers of pokeweed mitogen-induced anti-sheep erythrocyte PFC (P < 0.01) as compared with normals and patients with glandular disease. Of note was the fact that despite the modulation of T(G) subpopulation by the serum factor in patients with extra-glandular disease, these patients manifested normal concanavalin A-generated suppressor cells of pokeweed mitogen-induced PFC responses in allogeneic co-cultures. This was unlike the suppressor cell defect previously described in this system with systemic lupus erythematosus patients. The discrepancy was attributed both to the fact that the T(G) defect was reversible and to the fact that concanavalin A-generated suppressor cells are not limited to the T(G) subset. Thus, these studies have demonstrated reversible abnormalities in T(G) cells in patients with extraglandular Sjögren's syndrome which are not associated with suppressor cell defects. The discrepancy between these findings and the immuno-reg

Topics: Adult; Aged; B-Lymphocytes; Concanavalin A; Female; Humans; Immunity; Immunoglobulin G; In Vitro Techniques; Lupus Erythematosus, Systemic; Lymphocyte Activation; Male; Middle Aged; Mitogens; Receptors, Fc; Sjogren's Syndrome; T-Lymphocytes; T-Lymphocytes, Regulatory; Trypsin

In vitro responsiveness of spleen cells from NZP/NZW (B/W) female mice, aged 2 through 40 weeks, to the mitogens phytohemagglutinin (PHA), concanavalin-A (Con-A) and lipopolysaccharide (LPS) was determined. An age-related decline in proliferative response of splenic cells was found; this decline correlated with the age of onset and progression of lymphoid infiltration in lacrimal and salivary glands in the mice. The worsening with age of this lymphoid infiltrate, coupled with the decline in responsiveness to mitogens, suggests a complex immunopathologic process with destruction of glands terminating in a disease similar to the Sjögren syndrome in humans.

Topics: Age Factors; Animals; Cell Division; Concanavalin A; Female; Lacrimal Apparatus; Lectins; Lipopolysaccharides; Lymphocyte Activation; Lymphocytes; Mice; Mice, Inbred NZB; Mice, Inbred Strains; Mitogens; Salivary Glands; Sjogren's Syndrome; Spleen