Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A number of lines of evidence suggest that the lupus-like symptoms associated with procainamide therapy may be caused by products of metabolic N-oxidation. In the present study, the perfusion of the isolated rat liver with a hemoglobin-free solution containing procainamide (100 microM) resulted in the rapid appearance of the N-oxidation metabolite procainamide hydroxylamine in the perfusate. Addition of procainamide hydroxylamine in vitro to whole rat blood (1-40 microM) resulted in a concentration-dependent loss of proliferative response among mononuclear cells isolated from the treated blood and cultured with mitogens (phytohemagglutinin, PHA-P: concanavalin A, Con A; and pokeweed mitogen, PWM), as well as a loss of viability. Similar effects on lymphocyte mitogen responsiveness were observed when procainamide hydroxylamine (1-40 microM) was added to rat whole splenic cell populations. Carbon monoxide or ascorbic acid pretreatment inhibited the toxicity of procainamide hydroxylamine to lymphocytes in whole blood, but only carbon monoxide pretreatment inhibited procainamide hydroxylamine-induced methemoglobin formation. These observations are consistent with the participation of hemoglobin in a redox cycle with procainamide hydroxylamine, generating products which are primarily responsible for its cytotoxicity in blood.
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PMID:Procainamide hydroxylamine lymphocyte toxicity--I. Evidence for participation by hemoglobin. 247 7

This study examined the phosphorylation of cytoplasmic and nuclear proteins in peripheral blood mononuclear cells (PBMC) of systemic lupus erythematosus (SLE) patients. The cytoplasmic and nuclear protein kinase activity in PBMC from SLE patients was at least five-fold higher than that of normal healthy subjects. PBMC of SLE patients produced different nuclear endogenous substrates on phosphorylation and also displayed distinct protein kinase activity. Nuclear phosphoproteins, with human PBMC DNA-binding ability, of 38 kD and 70 kD were detected from both SLE patients and normal healthy subjects, while the 40 kD phosphoprotein, with tyrosine as the main phosphorylation residue, was found only in SLE patients. Other nuclear phosphoproteins, and most of the detected cytoplasmic phosphoproteins, were present in higher levels in both normal PBMC with mitogen stimulation, such as PHA, and SLE PBMC. The expression level of the 40 kD nuclear phosphotyrosyl-protein showed a positive correlation with the clinical disease activity of SLE. These results suggest that PBMC from SLE patients had distinct tyrosine protein kinase (TPK) activity and/or a different endogenous substrate of nuclear DNA-binding proteins in tyrosine phosphorylation. The possible significance of tyrosine phosphorylation in PBMC of SLE patients in the pathogenesis, and its clinical meaning, are discussed.
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PMID:Nuclear phosphotyrosyl-protein with DNA-binding ability in peripheral blood mononuclear cells from systemic lupus erythematosus patients. 270 78

In 24 patients with systemic lupus erythematosus the proliferating response of lymphocytes of the peripheral blood stream to mitogens PHA, ConA and PWM was examined. The spontaneous incorporation of 3H-thymidine was increased in two patients. The mean response to PHA and PWM was reduced, while the response to ConA was within the normal range. In the active stage of the disease the lymphocyte response was in general lower in the stage of low activity. There was no correlation between the number of CD4 and CD8 lymphocytes nor the CD4/CD8 index and the lymphocyte response to mitogens. In systemic lupus erythematosus the response to PWM was lower than in rheumatoid arthritis, while in rheumatoid arthritis the response to PHA and ConA was lower than in systemic lupus erythematosus.
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PMID:[Response of peripheral blood lymphocytes to antigenically nonspecific mitogens in systemic erythematosus]. 276 36

The expression of a new activation antigen, T cell lineage specific activation antigen (TLiSA1) on peripheral blood T cells from 16 rheumatoid arthritis (RA) and 8 systemic lupus erythematosus (SLE) patients and synovial fluid T cells from RA patients was determined in the context of T cell activation. The percentages of TLiSA1 positive T cells from inactive (4.6 +/- 5.2, mean +/- SE) or active RA (19.3 +/- 8.6) or inactive (1.7 +/- 2.1) or active SLE (8.7 +/- 2.7) were significantly increased compared with that of normal controls (0.7 +/- 0.4) (P less than 0.01). All patients with vasculitis showed relatively high positive percentages. The mean fluorocytometric intensity of TLiSA1 positive T cells from RA and SLE patients was significantly higher than that from normals. Percentages of TLiSA1 positive T cells from synovial fluids (21.8 +/- 4.9%) were significantly increased compared with those from peripheral blood of the same patients, indicating the local activation of T cells in patients with RA. An increase in the expression of TLiSA1 with no increase in the expression of the very late activating antigen 1 (VLA-1) was found in peripheral blood from RA, suggesting a difference in the stage of T cell activation in RA. In RA, there was a clinical correlation with levels of TLiSA1 expression on peripheral T cells. After stimulation with PHA, TLiSA1 positive percentages were increased on Day 2 and continued to increase through 5 days of culture. The maximum expression was obtained on Day 5. An increased number of TLiSA1 positive T cells belonged to OKT8. These results suggest that there is the systemic and the local activation of T cells in RA, following antigen stimulation, or a generalized nonspecific activation of immune system that could provide a means to monitor the abnormal immunologic activity in RA.
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PMID:Expression of TLiSA1 on T cells from patients with rheumatoid arthritis and systemic lupus erythematosus. 278 52

The effect of polymorphonuclear leukocytes (PMNs) on lymphocyte subpopulations and their reactivity was investigated by adding supernatants obtained by culturing PMNs with allogeneic or autologous lymphocytes which had been pre-treated with prostaglandin (PG) synthetase inhibitors. PMNs were obtained from 12 healthy individuals, 7 patients with systemic lupus erythematosus (SLE) and 6 patients with bacterial infections. Freshly prepared normal lymphocytes pretreated with PG synthetase inhibitors were incubated with the above supernatants, and the lymphocyte and T-lymphocyte subpopulations were then quantitated, the responses of lymphocytes to mitogens measured and the generation of helper and suppressor T-cell activities for PWM-stimulated cultures assessed. We also ascertained which T-cell population, i.e. OKT4+ or OKT8+ cells, which had been altered by incubation with supernatants, was responsible for the suppressor T-cell activity. A reduced per cent of OKT4+ cells; depressed responses to Con A, PHA, PWM and allogeneic lymphocytes, impaired helper T-cell activity; and increased suppressor T-cell activity were noted after incubation of lymphocytes with supernatants. The percentage of T lymphocytes and of OKT8+ cells was, however, not affected. Further, enhanced suppressor T-cell activity was obtained when supernatant-incubated OKT4+ cells were cultured with OKT8+ cells, regardless of whether the latter had previously been exposed to supernatants. Addition of PG inhibitors to PMN co-cultures nearly restored the original percentage and reactivity of the T-lymphocyte populations, indicating a role for PG released from PMNs in the effects observed. The amount of PG demonstrated in co-culture supernatants was 30 times more than obtained by sonification of fresh PMNs and 10 times more than found in the culture medium containing PMNs alone. These results suggest that, besides monocytes, other phagocytes, including PMNs, can modulate lymphocyte-mediated immune reactivity by the release of PG. Deceased number of OKT4+ cells, impaired helper T-cell activity and enhanced suppressor cell activity may, at least in part, result from the effect of PG released from PMNs as well as monocytes.
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PMID:Modulation of the immunoreactivity of a T-lymphocyte subpopulation by neutrophil-released prostaglandin. 293 29

Analysis of T cells from patients with systemic lupus erythematosus (SLE) and with rheumatoid arthritis (RA) identified a deficit in the induction of HLA Class II antigens by PHA although the proliferative response was normal and in the [3H]thymidine incorporation in autologous mixed lymphocyte reactions (MLR) with PHA-T cells as stimulators. In RA these abnormalities were more marked in patients with active disease than in those in clinical remission. The deficit of autologous MLR with PHA-T cells was more marked than that of autologous MLR with non-T cells and of allogeneic MLR. Serum from patients with SLE and with RA did not display any detectable inhibitory activity on the induction of HLA Class II antigens by PHA, on the proliferative response of lymphocytes to PHA, on autologous MLR with PHA-T cells and with non-T cells as stimulators and on allogeneic MLR. These results suggest that the abnormalities we have identified reflect an intrinsic defect of T cells.
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PMID:PHA-T cells in systemic lupus erythematosus and in rheumatoid arthritis: abnormalities in HLA class II antigen induction and in autologous mixed lymphocyte reactions. 294 25

MDL-899 is new phthalazine derivative which has been developed as a substitute for hydralazine, which has several undesirable effects, in the treatment of hypertension. The effects of MDL-899 on human lymphocyte functions are analyzed. This drug inhibited in a dose-related fashion the blastogenesis of lymphocytes upon PHA and Con A activation and down-regulated the activation of allogeneic mixed lymphocyte reactions (MLR). On the contrary the drug enhanced the activation of autologous MLR of non T/T type. This effect was five times higher on cells which carried the HLA DR 4 phenotype. The above reported observations suggest that MDL-899, as well as hydralazine, affects the in vitro responsiveness of human lymphocytes mostly in subjects with HLA-DR 4 phenotype. Whether the impact of MDL-899 on immune function gives rise to a lupus like syndrome is not known. For this reason further studies are warranted to assess its long-term in vivo effects.
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PMID:The effects of a new phthalazine derivative (MDL 899) on human lymphocyte functions. 294 87

Interleukin 2 (IL 2) secretion in response to mitogenic stimulation in vitro is strongly reduced in circulating T lymphocytes from patients with SLE. It is still not clear how this abnormality relates to the B cell hyperactivity in the disease. Some investigators proposed that an intrinsic T helper cell defect could lead to suppressor cell dysfunction and autoimmunity. Others have found that in fact increased suppressor cell activity can cause IL 2 hyposecretion. In the present study we report that the IL 2 secretion in response to PHA plus PMA by T cells from patients with SLE, which initially was decreased by a factor of 10 as compared with the IL 2 secretion in blood donor T cells, was restored when the T cells were rested for 2 to 3 days in culture before stimulation. IL 2 hyposecretion in SLE T cells and the kinetics of normalization in culture were not changed by the addition of normal adherent cells during the stimulation with PHA/PMA, occurred in the absence of significant cell death or proliferation or change of the T4:T8 cell ratio during the resting culture, were not due to a maturation of immature T6-positive cells (less than 1.5% T6 cells in SLE T cells), and also occurred in T8-depleted T4 cells alone. Furthermore, a normalization of IL 2 secretion took place in the presence of either SLE serum or normal serum, and the addition of fresh autologous T cells to 3-day-cultured SLE T cells did not cause suppression of IL 2 secretion. These data show that some rapidly reversible defect occurs in circulating T helper cells in SLE. That this could reflect an exhaustion of T helper cells that have been activated in vivo is discussed.
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PMID:The interleukin 2 secretion defect in vitro in systemic lupus erythematosus is reversible in rested cultured T cells. 294 62

Peripheral lymphocytes stimulated with phytohemagglutinin (PHA-blasts) were examined for their responsiveness to exogenous interleukin 2 (IL-2). The proliferative response of PHA-blasts to IL-2 was significantly lower in patients with systemic lupus erythematosus (SLE) than in normal subjects. To clarify the reason for this defect, the expression of IL-2 receptor (IL-2R) on PHA-blasts was investigated using anti-Tac antibody and purified IL-2. Cytofluorometric analysis showed no statistical differences in the Tac positivity of PHA-blasts among normal subjects and patients with active and inactive SLE. Scatchard analysis using 125I-labeled anti-Tac monoclonal antibody revealed that the number of Tac epitopes on PHA-blasts was also not different among them. Next, the affinity of IL-2R expressed on PHA-blasts was determined by Scatchard analysis using radiolabeled IL-2 as a ligand. The number of high affinity IL-2R on the PHA-blasts was significantly decreased in patients with active and inactive SLE, as compared with normal subjects. The responsiveness of PHA-blasts to exogenous IL-2 was well correlated to the number of high affinity IL-2R, but not to the number of Tac epitopes or total IL-2R. Inasmuch as high affinity components of IL-2R are functionally active, the defective expression of high affinity IL-2R may be responsible for the T cell dysfunctions in SLE.
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PMID:Impaired expression of high affinity interleukin 2 receptor on activated lymphocytes from patients with systemic lupus erythematosus. 311 22

Peripheral blood lymphocytes from patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), progressive systemic sclerosis (PSS), Reiter's disease, osteoarthritis, and from healthy volunteers were investigated for interferon-gamma (IFN-gamma) production after mitogen activation. Phytohaemagglutinin stimulation revealed an impaired IFN-gamma production in RA, SLE, and PSS but normal levels in Reiter's disease and osteoarthritis. In RA this deficiency was also seen after pokeweed mitogen, OKT3, and concanavalin A activation. No major differences were found in interleukin 2 (IL-2) production and cell proliferation. The IL-2 receptor expression was reduced on stimulated RA lymphocytes. The deficient IFN-gamma production was compensated in RA by co-stimulation of PHA or OKT3 with phorbol myristic acetate (PMA). In addition, the combination of the calcium ionophore A 23187 and PMA induced a strong IFN-gamma secretion in all patient groups and in the controls.
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PMID:Impaired mitogen-induced interferon-gamma production in rheumatoid arthritis and related diseases. 312 62


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