Suppressor cell function defect in idiopathic systemic lupus erythematosus

Gingival and periodontal health in systemic lupus erythematosus

This study compared the periodontal health of patients with SLE with that of healthy controls. Patients with systemic lupus erythematosus had significantly lower periodontal probing depths compared with healthy controls. It is possible that systemic drugs such as corticosteroids and NSAIDS may be responsible for these reduced probing depths but this study did not reveal a statistically significant effect of drugs. There is thus no evidence for a predisposition to increased periodontal disease in SLE.

A long-term immunological study of childhood onset systemic lupus erythematosus

Immunological dysregulation is an important cause of the development of systemic lupus erythematosus (SLE). Serological evaluation has been useful in the clinical management of patients and as a prognostic indicator. Sixteen patients who developed SLE as children were followed up for more than three years and immunological data collected. The results showed that (a) complement C3 concentration was lower in the active stage of SLE, especially during a major clinical exacerbation, but rarely preceded a major flare up. The concentration was often normal during the mildly to moderately active stage. In contrast, a low complement C4 concentration often preceded a major clinical exacerbation and could be of longer duration, sometimes persisting regardless of disease activity. (b) A T cell subset distribution study showed persistently low CD4 positive T cells in the peripheral blood of patients with SLE during the long term follow up, strongly suggesting that the intrinsic defect is mainly localised in T helper/inducer cells. These abnormal cellular defects did not tend to return to normal even in long term remission. (c) The persistently higher serum interleukin 2 and interleukin 2 receptor concentrations in SLE strongly suggested that the T cells were preactivated in vivo and that these phenomena might persist even in remission. (d) The best single parameter for predicting active SLE was anti-dsDNA. It was highly correlated with disease activity in most patients, and the asymptomatic increase of anti-dsDNA (greater than or equal to 60 U/ml, radioimmunoassay) was often followed by a major clinical exacerbation, especially in patients with a simultaneously low complement C4 concentration, suggesting that it might be an important warning sign of a major flare up. High dose steroids are indicated in this group of patients.

Segregation of lymphocyte low-molecular-weight DNA and antinuclear-antibodies in a family with systemic lupus erythematosus in first cousins

All patients with systemic lupus erythematosus (SLE) demonstrated two classes of newly synthesized DNA in sucrose density gradients of PHA (phytohemagglutinin)-stimulated lymphocytes: a large-molecular-weight fraction that comigrates with control DNA and an excess low-molecular-weight DNA (LMW-DNA) fraction not found in control lymphocytes. Excess LMW-DNA was independent of disease activity or drug therapy. LMW-DNA and serologic abnormalities were studied in a four-generation family in which two first cousins had SLE. Excess LMW-DNA was found in the cousins with SLE, sibling parents of the SLE patients, a common grandparent, four of nine siblings of one patient, and five of seven at risk children. Both males and females had excess LMW-DNA. Male-male transmission was observed. The expression of excess LMW-DNA in stimulated lymphocytes is inherited as an autosomal dominant genetic trait in this family. All unaffected adult family members with the marker had positive antinuclear antibodies (ANAs) except the grandmother. However, none of the five children with excess LMW-DNA showed positive ANAs. Excess LMW-DNA precedes the appearance of ANAs when found in children of adults with excess LMW-DNA, and may be a predisposing factor in the development of the immunologic responses of systemic lupus erythematosus.

In vitro T-cell functions specific to an anti-DNA idiotype and serological markers in patients with systemic lupus erythematosus (SLE)

The human monoclonal autoantibody 16/6 is a common anti-DNA idiotype found to have clinical relevance in patients with systemic lupus erythematosus (SLE). Therefore the ability of peripheral blood T cells of SLE patients and healthy controls to proliferate and to produce helper T-cell factors following stimulation with this idiotype was tested. It was found that T cells of 75% of healthy donors proliferated to the 16/6 idiotype, whereas only 22% of SLE patients responded to this idiotype by proliferation. On the other hand, the capability to produce T-cell helper factors specific to the 16/6 idiotype was found in a higher percentage of SLE patients (48%) as compared to healthy controls (31%). The low frequency of proliferative responses in SLE patients might be due either to the chronic exposure to the 16/6 idiotype or to the production of antiidiotype antibodies against the 16/6 idiotype, which interfere with the response to the latter stimulator.

Increased immunoglobulin response to gamma-interferon by lymphocytes from patients with systemic lupus erythematosus

The factors responsible for abnormal B-cell activation in systemic lupus erythematosus (SLE) are incompletely understood. This study tested the hypothesis that the abnormal B-cell activation observed in human SLE may be due to an augmented response to a helper signal. We demonstrated that non-T cells from 10 of 19 SLE patients increased IgG production in response to interferon-gamma (IFN-gamma) by a mean factor of 20.9 +/- 3.9 over resting levels, while controls stimulated a mean factor of 3.0 +/- 0.5 (P less than 0.005). We found no relationship of IFN-gamma responsiveness to disease activity. Serotyping for HLA A, B, C, and D loci suggested that the hyperresponsiveness may be genetically linked to HLA-Cw7. We conclude that IFN-gamma may contribute to the development and perpetuation of SLE in a subset of patients with SLE.

Immunoregulation in severe generalized periodontitis

Severe generalized periodontitis (SGP) is an inflammatory disease which leads to extensive alveolar bone loss in young adults. Peripheral blood lymphocytes from SGP patients have been previously reported to exhibit an in vitro hyperproliferative response when exposed to B cell mitogens derived from Staphylococcus aureus and Actinomyces viscosus. Therefore hyperresponsiveness to B-cell mitogens could be an important pathogenic factor in the susceptibility to and progression of SGP. We have tested whether the hyperproliferative response of lymphocytes from SGP patients was due to (i) a functional deficiency of suppressor T cells, or (ii) to numerical alterations of lymphocytes. Supernatant fluids from concanavalin A-stimulated T cells from 14 SGP patients and 14 normal subjects were compared for their ability to suppress the IgM synthesis of B-cell mitogen-stimulated mouse splenocytes. No significant differences were noted in suppressor T-cell function between control subjects and SGP patients. However, SGP patients had significantly higher lymphocyte counts than control subjects, and there was a positive correlation between high lymphocyte counts and high mitogen-stimulated proliferation. SGP patients also had higher lymphocyte:monocyte ratios than control subjects, suggesting that a defect in macrophage-mediated suppression might be involved in the hyperproliferation phenomenon. Our data do not support the hypothesis that a suppressor T-cell defect is the cause of mitogen-induced hyperproliferative responsiveness of peripheral blood lymphocytes from SGP patients. Rather, hyperproliferation may be due to an expansion of the lymphocyte pool which responds to mitogens, or/and a regulatory disturbance which arises because of altered lymphocyte:macrophage ratios.

Identification of B-cell and T-helper-cell defects, and of suppressor cell hyperactivity, in humoral immunodeficiency

Methods are described for distinguishing between intrinsic B-cell defects, T-helper-cell defects, and suppressor cell hyperactivity in patients who fail to secrete immunoglobulin when peripheral blood mononuclear cells are stimulated with pokeweed mitogen. Control cells which respond to pokeweed mitogen are made unresponsive by depleting B cells or OKT4+ cells, and the missing subset, purified from the patient's peripheral blood mononuclear cells, is added back to examine its functional activity. Alternatively, hyperactivity of OKT8+ putative suppressor T cells or suppressor monocytes is evaluated by depleting these populations from the patient's peripheral blood mononuclear cells. Four patients who produced few plaque-forming cells in response to pokeweed mitogen were investigated: two had intrinsic B-cell deficiencies, one had T-helper-cell deficiency, and one had T-suppressor-cell hyperactivity.

Interleukin 2 induction of antigen-nonspecific suppressor cells

Although Interleukin 2 (IL-2) is essential to the generation of immune responses it may also be important as a regulator of these same responses, as both primary and secondary anti-SRBC responses are greatly diminished when IL-2 is included in culture. IL-2 must be present within the first 24 hr of culture to affect maximum suppression. This inhibition is mediated by suppressor cells which are expanded by pulsing spleen cells with IL-2 for 48-72 hr. Their development is not antigen dependent and their action is antigen nonspecific. Suppressor cell activity can be generated from either naive or primed animals which are equally effective in inhibiting primary or secondary anti-SRBC responses. Suppressor cells can be propagated for long periods of time in T-cell growth factor-containing medium. These long-term cultured cells retain the ability to inhibit various immune responses such as mitogen- and alloantigen-induced proliferation, the generation of cytotoxic T lymphocytes and humoral responses. These cells suppress these responses by absorbing IL-2, as demonstrated by their ability to remove IL-2 upon incubation at 4 degrees C, and the reversal of suppression by the addition of supraoptimal amounts of IL-2.

Impaired T cell capping and receptor regeneration in active systemic lupus erythematosus. Evidence for a disorder intrinsic to the T lymphocyte

It is currently unclear whether the T cell dysfunctions observed during active systemic lupus erythematosus (SLE) reflect a disorder intrinsic to the T cell or defects that result from interaction with anti-T cell autoantibody. To determine whether a disorder intrinsic to the T cell exists in SLE, the T cell capping mechanism was selected as a model of cellular function. The normal T cell capping mechanism is a rapid, energy-dependent and coordinated sequence of membrane events that consists of microaggregation, capping, endocytosis, and regeneration of the surface molecule. The monoclonal antibodies OKT3, OKT4, and OKT8, directed against the T cell-specific membrane glycoproteins T-3, T-4, T-8, served as specific probes of the glycoproteins' mobility within the membrane and membrane glycoprotein regeneration. When compared with greater than 91% T cell capping in normal and control subjects with active Sjögren's syndrome, active rheumatoid arthritis and active tuberculosis, only 49-60% of T cells from active SLE patients completed the capping sequence (SLE vs. healthy controls; T-3, P less than 0.002; T-4, P less than 0.004; T-8, P less than 0.002). Colchicine (10(-5) M), which inhibits microtuble polymerization and augments the rate of normal T cell capping, failed to restore the abnormal capping. However, as judged by the elapsed time intervals to half-maximal capping, the capping kinetics of the T cells able to initiate capping were not significantly different from controls. Fluorescence microscopy demonstrated an abnormal staining pattern characterized by microaggregation of ligand-glycoprotein complexes on resting T cells, coarse aggregation of ligand-glycoprotein complexes over the surfaces of cells that failed to cap, and cleaved or disrupted caps. After clearance of determinants by capping, greater than 94% of T cells from healthy controls regenerated T-3, -4, and -8 within 24 h. In contrast, only 20-40% of capped T cells from active SLE patients reexpressed new determinants. With improving disease activity, the proportion of cells capping and regenerating T-3, -4, and -8 increased, but remained significantly below control levels. In conclusion, this study has identified a disorder of T cell surface glycoprotein mobility and regeneration affecting the majority (60-80%) of both the T-3+, T-4+, (inducer/helper), and T-3+, T-8+ (suppressor) subsets during active SLE. Although the impaired capping and reexpression improve with disease remission, a residual defect persists. The data support the concept of a disorder intrinsic to the T cell in SLE.

T lymphocyte subsets in systemic lupus erythematosus. Correlations with corticosteroid therapy and disease activity

The contribution of immune regulation to the etiology of systemic lupus erythematosus (SLE) is poorly understood. Using the monoclonal antibodies OKT4 and OKT8, we quantitated, by flow cytometry, T inducer/helper and T cytotoxic/suppressor cells in patients with SLE. Serologically active patients, who had clinical manifestations such as arthritis or rash and were not receiving prednisone, were characteristically lymphopenic due to a marked reduction in OKT4+ cells. Prednisone therapy produced the same phenomenon. Untreated patients, who were serologically inactive, demonstrated no abnormalities. These studies have thus revealed two presumably independent factors that can produce similar immunoregulatory aberrations.

Abnormal immunoregulation in patients with insulin dependent diabetes mellitus and their healthy first degree relatives

Autoantibodies, cell-mediated autoimmunity, and impaired suppressor T cell function, suggesting abnormal immunoregulation, have been implicated in the pathogenesis of juvenile-onset insulin dependent diabetes mellitus (IDDM). To examine one of the parameters of immunoregulation, and to explore its relationship to the disease, we tested suppressor cell function in IDDM patients, their clinically healthy relatives, and in normal unrelated controls. 9/15 IDDM had impaired suppressor cell function compared to 1/8 age-matched healthy sibs (p less than 0.04) and to 0/9 unrelated controls (p less than 0.005). There was no correlation between abnormal suppressor cell function and the patient's age, sex, preprandial blood glucose levels, age at the time of diagnosis, or duration of the disease. However, there was a trend for a higher proportion of HLA Dr3 positive diabetics to have abnormal suppressor cell function compared to DR3 negative patients. Impaired suppressor cell function was also found in 5/23 clinically healthy first degree relatives; 4/5 were related to a diabetic who demonstrated abnormal suppressor cell function. These findings raise the possibility that underlying familial, probably genetically determined abnormalities in immunoregulation, acting in concert with other environmental or genetic factors, may contribute to disease susceptibility in IDDM.

Systemic lupus erythematosus - a state of hyperinterferonemia?

On the basis of immunologic and microbiologic data as well as recent observations it is postulated that interferon is responsible for many of the clinical signs and symptoms in systemic lupus erythematosus such as alopecia, joint manifestations, fever and leukopenia. Recognition of the important role of interferon in active systemic lupus erythematosus leads to some practical conclusions: a) a new therapeutic approach to active lupus must consider a treatment which will lead to reduced interferon activity; b) one of the laboratory parameters of activity of the disease may be interferon measurements.

Normal suppressor-cell activity in systemic lupus erythematosus. A study on 26 cases

Suppressor-cell activity of 26 SLE patients suffering from active disease was compared to that of 15 healthy controls. ConA-induced and spontaneous suppression was evaluated. The mitogen-driven proliferation of normal allogeneic cells was significantly impaired by ConA-induced as well as spontaneous suppressor cells. However, no difference in suppressor-cell activity could be demonstrated between SLE patients and controls.

Enumeration of T-lymphocytes and T-lymphocyte subsets in rheumatoid arthritis using monoclonal antibodies

The number of T-lymphocytes and T-lymphocyte subsets was measured in peripheral blood of 51 patients with rheumatoid arthritis. T-lymphocytes were counted by E-rosette tests and by the immunogold staining method with OKT3.PAN monoclonal antibody. Helper and suppressor T-lymphocytes were determined by the immunogold staining method with OKT4.IND and OKT8.SUP monoclonal antibody. The relative and absolute numbers of T-lymphocytes and helper T-lymphocytes in peripheral blood of patients with RA did not differ significantly from those in the blood of healthy subjects. However, the relative and absolute numbers of suppressor T-cells were significantly lower in patients with RA than in healthy subjects. The decrease of suppressor T-cells in the blood of patients with RA dit not correlate with the activity of the disease nor the presence of the rheumatoid factor.

The pathogenesis of systemic lupus erythematosus

Many investigators believe that systemic lupus erythematosus is an autoimmune disease, perhaps caused by inadequate suppressor T lymphocyte activity, which permits the activation of autoantibody producing B lymphocytes. This paper discusses the testable hypothesis that a superoxide-generating, chromosome aberration-inducing factor (clastogenic factor), present in the lymphocytes of lupus patients but absent from normals, is responsible for such a suppressor cell defect. Superoxide or activated oxygen species derived from it, such as hydroxyl radical, may be the molecular mediators of CF activity.

Multiple sclerosis: heterology among early T cells and Tg cells

Circulating early T cells and TG cells were estimated simultaneously in 100 patients with multiple sclerosis and 21 controls. The results were analyzed from individual patients, from patients grouped according to disease activity, and from some patients studied longitudinally. Previously documented fluctuations in these two T cell populations were confirmed. By comparing the fluctuations and by examining the distribution of TG cells in suspensions of isolated early and isolated late T cells, it was found that TG cells are a T cell subpopulation distinct from early T cells.

Further aspects of T cell function in systemic lupus erythematosus

Generation of effector cells, the expression of cell mediated lympholysis (CML) and the reactivity of mononuclear cells in solid cultures, were explored in patients with Systemic Lupus Erythematosus (SLE). While proliferative responses to alloantigens were comparable to the controls, a significant decrease in CML capacity was found in SLE T lymphocytes; further, T cells stimulated with a T cell mitogen in solid cultures showed a diminished proliferative response to soluble factors. Functional cell interaction defects rather than intrinsic T cell abnormalities may be operating in SLE.

Depressed primary in vitro antibody response in untreated systemic lupus erythematosus. T helper cell defect and lack of defective suppressor cell function

The in vitro antibody response of peripheral blood lymphocytes (PBL) from 19 patients with untreated systemic lupus erythematosus (SLE) was compared with that of 20 control patients and 44 normal subjects. Trinitrophenyl polyacrylamide beads (TNP-PAA) were used to induce IgM anti-TNP plaque-forming cells. SLE patients displayed a markedly depressed, and in most instances virtually absent, response. This was not due to an unusual kinetics of the response; nor could it be induced by preincubation of SLE patients' PBL. In co-cultures of SLE patients and normal PBL, the former, with few exceptions, did not exert a suppressive effect. In four patients the anti-TNP response of either unfractionated or T-depleted SLE PBL could be restored by T cells from a normal individual. Conversely in three of these patients, SLE T cells could not support the response of normal B cells, suggesting a T helper cell defect in SLE PBL. Concanavalin A (Con A)-induced suppressor cells of the antibody response could be assayed by two approaches: (a) in responder SLE patients, by the direct addition of Con A to TNP-PAA-stimulated cultures; (b) in seven patients by transfer of Con A-activated cells to the responding culture of a normal allogeneic donor. In both cases SLE PBL were able to exert a suppressive effect to the same extent as normal PBL.