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J E Balow

Publications and source records attributed to J E Balow.

At least 55 records · Page 3Linked to original sources

Glucocorticoid therapy for immune-mediated diseases: basic and clinical correlates.

Glucocorticoids are pleiotropic hormones that at pharmacologic doses prevent or suppress inflammation and other immunologically mediated processes. At the molecular level, glucocorticoids form complexes with specific receptors that migrate to the nucleus where they interact with selective regulatory sites within DNA; this results in positive and negative modulation of several genes involved in inflammatory and immune responses. At the cellular level, glucocorticoids inhibit the access of leukocytes to inflammatory sites; interfere with the functions of leukocytes, endothelial cells, and fibroblasts; and suppress the production and the effects of humoral factors involved in the inflammatory response. Clinically, several modes of glucocorticoid administration are used, depending on the disease process, the organ involved, and the extent of involvement. High doses of daily glucocorticoids are usually required in patients with severe diseases involving major organs, whereas alternate-day regimens may be used in patients with less aggressive diseases. Intravenous glucocorticoids (pulse therapy) are frequently used to initiate therapy in patients with rapidly progressive, immunologically mediated diseases. The benefits of glucocorticoid therapy can easily be offset by severe side effects; even with the greatest care, side effects may occur. Moreover, for certain complications (for example, infection diathesis, peptic ulcer, osteoporosis, avascular necrosis, and atherosclerosis), other drug toxicities and pathogenic factors overlap with glucocorticoid effects. Minimizing the incidence and severity of glucocorticoid-related side effects requires carefully decreasing the dose; using adjunctive disease-modifying immunosuppressive and anti-inflammatory agents; and taking general preventive measures.

Cells↗

Novel mechanism for inhibition of human T cells by glucocorticoids. Glucocorticoids inhibit signal transduction through IL-2 receptor.

Interaction of IL-2 with its high affinity membrane receptor complex (IL-2R) present on activated T lymphocytes induces cell proliferation and mediates effector functions. Glucocorticoids inhibit IL-2 production by inhibiting TCR-mediated signal transduction. We asked whether they also inhibit the action of IL-2 by inhibiting signal transduction through IL-2R. Human peripheral blood T cells, stimulated with PMA for 48 h (PMA blasts), were incubated with IL-2 in the presence of incremental dosages of dexamethasone (Dex; 10(-5)-10(-9) M). Dex inhibited the IL-2-dependent proliferation of PMA blasts in a dose-dependent fashion (IC50, 5 x 10(-8) M). Cell surface expression of IL-2R alpha- and beta-chains as determined by immunofluorescence analysis was not affected by Dex. In addition, Scatchard plot analysis of 125I-labeled IL-2 showed that Dex did not affect the binding of IL-2, thus suggesting that inhibition is due to a postreceptor effect. Inhibition of T cell proliferation by Dex was associated with decreased IL-2-dependent tyrosine phosphorylation of several intracellular proteins and decreased phosphorylation of the retinoblastoma gene product Rb, a protein essential for controlling the progression of cells through the cell cycle. IL-2-dependent IL-2R alpha expression in PMA blasts and NF-kB induction in resting human T cells were also inhibited by Dex. These results demonstrate that glucocorticoids inhibit preactivated T cells by down-regulating signal transduction through IL-2R.

Adult↗

Risk for sustained amenorrhea in patients with systemic lupus erythematosus receiving intermittent pulse cyclophosphamide therapy.

OBJECTIVE: To determine the risk for secondary amenorrhea after pulse cyclophosphamide therapy in premenopausal women with systemic lupus erythematosus. DESIGN: Controlled, retrospective clinical study. SETTING: Government referral-based research hospital. PATIENTS: Thirty-nine women younger than 40 years treated with pulse cyclophosphamide therapy for active lupus nephritis or neuropsychiatric lupus. Sixteen women who received pulses of intravenous methylprednisolone were controls. INTERVENTIONS: Sixteen patients received pulse cyclophosphamide (0.5 to 1.0 g/m2 body surface area) monthly for a total of 7 doses (short-CY), and 23 patients received 15 or more doses (long-CY). Control patients were treated with monthly pulses of methylprednisolone (1.0 g/m2) for a total of nine doses. MEASUREMENTS: Rates of amenorrhea were evaluated according to duration of treatment (number of doses) and age at the initiation of pulse therapy. RESULTS: Two of 16 patients (12%) in the Short-CY group and 9 of 23 (39%) in the long-CY group developed sustained amenorrhea (P = 0.07). Rates of sustained amenorrhea (short- and long-CY) according to age at the start of pulse therapy were: < or = 25 years, 2/16 (12%); 26 to 30 years, 4/15 (27%); > or = 31 years, 5/8 (62%) (P = 0.04). The increased risk for sustained amenorrhea in patients treated with long-CY was most evident in patients older than 25 years (short-CY [2/12] compared with long-CY [7/11]; P = 0.03). Three other patients with short-CY had reversal of amenorrhea fewer than 12 months after cessation of therapy. Amenorrhea was not observed in any of the 16 control patients. CONCLUSIONS: Intermittent pulse cyclophosphamide therapy in patients with systemic lupus erythematosus is associated with sustained amenorrhea, which is related to both age and number of doses of cyclophosphamide.

Adult↗

Effect of transforming growth factor-beta on early and late activation events in human T cells.

Transforming growth factors-beta (TGF-beta) modulate immune responses by inhibiting the proliferation of normal T lymphocytes. To examine the mechanism(s) of this inhibition, we studied the effect of TGF-beta 1 on selected events associated with the initiation and progression of the T lymphocyte cell cycle. Human peripheral blood T cells were stimulated with anti-CD3 mAb, PHA, PMA, or ionomycin, alone or in combination. TGF-beta 1 (0.5 to 10 ng/ml) partially inhibited the tyrosine phosphorylation of a 100-kDa protein, but not the calcium influx when cells were stimulated via TCR. Nuclear transcription of early activation genes (c-fos, c-jun, and c-myc) as determined by nuclear run-off assays, and steady state mRNA levels and/or protein products of intermediate activation genes (IL-2, IL-2R alpha, IL-2R beta, and transferrin receptor) were not affected by TGF-beta 1. Total cellular RNA synthesis and cell size after T cell stimulation were also not affected by TGF-beta 1. However, TGF-beta 1 inhibited the IL-2-dependent proliferation of Con A lymphoblasts by -50%. This inhibition was associated with the down-regulation of IL-2-mediated tyrosine phosphorylation of proteins of 120, 100, 85, 75, and 50 kDa. TGF-beta 1 also inhibited the IL-2-dependent phosphorylation of the retinoblastoma susceptibility gene product, which plays an important role in cell cycle progression. These results suggest that TGF-beta 1 inhibits T cell proliferation by down-regulating predominantly IL-2-mediated proliferative signals.

Adult↗

Evidence for linkage of the gene causing familial Mediterranean fever to chromosome 17q in non-Ashkenazi Jewish families: second locus or type I error?

Familial Mediterranean fever (FMF) is an autosomal recessive disorder of unknown pathogenesis, characterized by recurrent, self-limited attacks of fever with synovitis, peritonitis, or pleurisy. Using DNAs from affected Israeli families, we have recently mapped the gene causing FMF (designated MEF) to the short arm of chromosome 16, with two-point lod scores in excess of 20. In this report we consider the possibility of a second FMF susceptibility locus. Before discovering linkage to markers on chromosome 16, we had found suggestive evidence for linkage to chromosome 17q, with the following maximal two-point lod scores: D17S74 (pCMM86), Z = 2.47, (theta = 0.20); D17S40 (pLEW101), Z = 2.15 (theta = 0.15); D17S35 (CRI-pP3-1), Z = 1.78 (theta = 0.15); D17S46 (pLEW108), Z = 1.69 (theta = 0.18), D17S254, Z = 2.30 (theta = 0.20). Moreover, multipoint linkage analysis using D17S74 and D17S40 as fixed loci gave Z = 3.27 approximately 10 centimorgans (cM) telomeric to D17S40. Data with the chromosome 17 markers alone in our families suggested locus heterogeneity. Nevertheless, our families were not separable into complementary subsets showing linkage either to chromosome 16 or to chromosome 17. We also examined the possibility that the positive lod scores for chromosome 17 might reflect a secondary, modifying locus. By several measures of disease severity, families with positive lod scores for chromosome 17 loci had no worse disease than those with negative lod scores for these loci. We conclude that chromosome 17 does not encode a major FMF susceptibility gene for some of the families, nor does it encode a disease-modifying gene. Rather, it would appear that linkage to chromosome 17 is a "false positive" (type I) error. These results reemphasize the fact that a lod score of 3.0 corresponds to a posterior probability of linkage of 95%, with an attendant 1 in 20 chance of observing a false positive.

Blotting, Southern↗

Renal vasculitis.

During most of the 20th century, the medical literature on systemic vasculitis has been dominated by "splitters," who sought to characterize the precise clinical and pathologic differences among these diseases. However, in the past decade in particular, those interested in renal vasculitis have tended to become "lumpers," who stressed overlap, particularly among patients with microscopic polyarteritis, necrotizing and crescentic glomerulonephritis, and Wegener's granulomatosis. The discovery of antineutrophil cytoplasmic antibodies has provided additional evidence of commonality among these renal vasculitides. The overlapping extended, to a considerable extent, to therapy as well. In the presence of severe glomerulonephritis, there is general consensus that methylprednisolone and cyclophosphamide are the preferred induction therapies. Controlled trials mostly fail to support the efficacy of adjunctive plasma exchange. Attempts to minimize risks of cyclophosphamide therapy focus on maintenance therapy with azathioprine or intermittent pulse cyclophosphamide. Contemporary series show that 5-year patient and kidney survival rates with antineutrophil cytoplasmic antibody-associated renal vasculitis range from 60% to 80%.

Humans↗

Controlled trial of pulse methylprednisolone versus two regimens of pulse cyclophosphamide in severe lupus nephritis.

Pulse cyclophosphamide is more effective than prednisone alone in preventing renal failure in lupus nephritis. We undertook a randomised, controlled trial to find out whether pulse methylprednisolone could equal pulse cyclophosphamide in preserving renal function in patients with lupus nephritis, and whether there was a difference between long and short courses of pulse cyclophosphamide in preventing exacerbations. 65 patients (60 female, 5 male; median [range] age 29 [10-48] years) with severe lupus nephritis were assigned randomly to monthly pulse methylprednisolone for 6 months (25 patients), monthly pulse cyclophosphamide for 6 months (20), or monthly cyclophosphamide for 6 months followed by quarterly pulse cyclophosphamide for 2 additional years (20). Patients treated with pulse methylprednisolone had a higher probability of doubling serum creatinine than those treated with long-course cyclophosphamide (p less than 0.04). Risk of doubling creatinine was not significantly different between short and long course cyclophosphamide. However, patients treated with short-course cyclophosphamide had a higher probability of exacerbations than those treated with long-course cyclophosphamide (p less than 0.01). An extended course of pulse cyclophosphamide is more effective than 6 months of pulse methylprednisolone in preserving renal function in patients with severe lupus nephritis. Addition of a quarterly maintenance regimen to monthly pulse cyclophosphamide reduces the rate of exacerbations.

Adolescent↗

Mapping of a gene causing familial Mediterranean fever to the short arm of chromosome 16.

BACKGROUND: Familial Mediterranean fever is an autosomal-recessive disease characterized by acute attacks of fever with sterile peritonitis, pleurisy, or synovitis. The biochemical basis of the disease is unknown, but determining the chromosomal location of the gene for the disorder should be a first step toward defining the biochemical events. METHODS AND RESULTS: As part of a systematic genome-wide search, we sought evidence of linkage between familial Mediterranean fever and chromosome 16 DNA markers in 27 affected non-Ashkenazi Jewish families from Israel. Two loci from the subtelomeric region of the short arm of chromosome 16 (16p) had lod scores sufficient to establish linkage (a score greater than or equal to 3). One DNA marker (D16S84) gave a maximal lod score of 9.17 (odds of 10(9.17) to 1 in favor of linkage) at a recombination frequency (theta) of 0.04. A probe associated with the hemoglobin alpha complex (5'HVR) gave a maximal lod score of 14.47 at a theta of 0.06. Multipoint linkage analysis indicated that the following was the most likely gene order: the centromere, the gene for familial Mediterranean fever, D16S84, hemoglobin alpha, and the telomere. The maximal multipoint lod score was 19.86. There was a striking degree of homozygosity at chromosome 16p loci in the affected offspring of eight consanguineous couples. CONCLUSIONS: The gene that causes familial Mediterranean fever in non-Ashkenazi Jews maps to the short arm of chromosome 16.

Centromere↗

NIH conference. Membranous nephropathy.

Membranous nephropathy is a worldwide problem that accounts for about 20% of the cases of the adult-onset nephrotic syndrome. This disease places many patients at risk for both end-stage renal failure and the complications of hyperlipidemia. Immune-mediated injury to the glomerular capillary wall in patients with membranous nephropathy is characterized by subepithelial immune complex formation and generation of the membrane attack complex of complement. Glomerular capillary hypertension, hyperlipidemia, and possibly cytokines could contribute to the glomerular sclerosis seen in the advanced stages of the disorder. In some cases, production of pathogenic antibody can be suppressed by treating the underlying condition. The mechanisms of action of immunosuppressive agents are being investigated and treatments are being tested in clinical trials to optimize the balance of efficacy and toxicity. Alternate-day treatment with corticosteroids is often recommended for nephrotic patients with idiopathic membranous nephropathy, but this approach has not been proved beneficial. Ongoing studies are evaluating whether cytotoxic drugs or cyclosporin A combined with prednisone is more effective than treatment with corticosteroids alone. Lipid-lowering drug therapy is warranted in cases of the persistent nephrotic syndrome to avert the cardiovascular sequelae of hyperlipidemia.

Animals↗

Modulation of mouse complement receptors 1 and 2 suppresses antibody responses in vivo.

A mAb, 7G6, that binds to mouse CR1 and CR2 and down-modulates their expression on splenic B cells in vivo, was used to determine whether a decrease in CR1 and CR2 expression affects antibody responses to different T-dependent and T-independent Ag. Injection of mice with the mAb 7G6 prior to immunization with FITC haptenated Salmonella typhimurium (SH5771), Salmonella montevideo (SH5770), SRBC, or Ficoll dramatically decreased subsequent antibody responses to FITC. Although both IgM and IgG primary antibody responses were affected similarly, the antibody levels were most inhibited during early phases of the response. In contrast, down-modulation of the CR did not affect memory antibody responses, because injection of mice with 7G6 before a second immunization with FITC-SH5771 had no effect on subsequent anti-FITC antibody production. Moreover, polyclonal in vivo activation of the mouse immune system by anti-mouse IgD antibodies was not affected by previous administration of 7G6, because anti-IgD-induced increases in Ia expression and serum IgG1 levels were not affected. Taken together, these observations suggest that CR1 and CR2 may play an important role in enhancing primary antibody responses to many T-dependent and T-independent Ag and may contribute to a host's response to naturally occurring antigens such as bacteria.

Animals↗

Kidney disease in systemic lupus erythematosus.

Glomerulonephritis is a major determinant of outcome in patients with systemic lupus erythematosus. Persistently active lupus nephritis imposes serious threats of end-stage renal failure and cardiovascular morbidity. Sustained corticosteroid treatment has been characterized as having an uncertain net benefit on the control of lupus nephritis, mainly because these drugs have relatively weak efficacy and they have been shown to confer their own set of cardiovascular risk factors. Controlled trials of corticosteroids, azathioprine and cyclophosphamide have demonstrated that the best control of clinical activity of proliferative lupus nephritis is attained with cyclophosphamide. To date, intermittent pulse cyclophosphamide treatment has produced the most favorable balance of efficacy and toxicity in patients with lupus nephritis.

Adrenal Cortex Hormones↗

Pulse cyclophosphamide for severe neuropsychiatric lupus.

We studied the effect of parenteral pulse cyclophosphamide therapy in nine patients with active systemic lupus erythematosus and severe central nervous system involvement. Seven patients had focal neurological deficits and/or seizures associated with abnormalities on cerebrospinal fluid analysis and/or magnetic resonance imaging. Two patients had organic brain syndrome with psychosis and normal cerebrospinal fluid and/or magnetic resonance imaging analysis. Six patients were unresponsive to treatment with high dose corticosteroid. Cyclophosphamide, 0.75-1.0 g/m2 body surface area, was administered intravenously every month for at least 2 months. Eight patients had a complete recovery or recovered with minor residuals. Cyclophosphamide was well tolerated with few side effects. We conclude that parenteral pulse cyclophosphamide is an effective adjunctive therapy for the management of patients with active systemic lupus erythematosus and central nervous system symptoms.

Adolescent↗

Dexamethasone inhibits human interleukin 2 but not interleukin 2 receptor gene expression in vitro at the level of nuclear transcription.

Glucocorticosteroids have an inhibitory effect on the expression of interleukin 2 (IL-2) and interleukin 2 receptor (IL-2R) genes. To determine the mechanisms of this inhibition, human T lymphocytes were stimulated with mitogens in the presence of dexamethasone. Nuclear transcription run-off assays showed that high doses of dexamethasone inhibited the transcription of the IL-2 gene but not that of the IL-2R gene. Post-transcriptionally, high doses of dexamethasone (10(-4) M) were required to inhibit IL-2R mRNA levels by 50%, whereas lower doses (10(-6) M) inhibited by greater than 70% the accumulation of IL-2 mRNA. IL-2 mRNA half-life decreased in the presence of dexamethasone (10(-6) M) by approximately 50%. At the protein product level, dexamethasone inhibited both IL-2 production, as well as cell surface and soluble forms of IL-2R. IL-2R gene expression was inhibited for at least 72 h after exposure of cells to dexamethasone. In the presence of exogenous IL-2, dexamethasone failed to exert a significant effect on the production of IL-2R protein. These data indicate that dexamethasone has a greater effect on the expression of the IL-2 gene than on the IL-2R gene. Dexamethasone both inhibits transcription of the IL-2 gene and decreases the stability of IL-2 mRNA. The effect of dexamethasone on the IL-2R gene is post-transcriptional and may result indirectly from decreased IL-2 production.

Dexamethasone↗

Gene transcription during in vitro activation of human B lymphocytes with Staphylococcus aureus Cowan I strain.

With the use of nuclear transcription run-off assays we have determined the kinetics of transcriptional activity for the c-fos, c-myc, DR beta, DQ beta, (TfR), Blast-1, and Ig kappa genes in human tonsillar B lymphocytes of high to intermediate density after stimulation with Staphylococcus aureus Cowan I strain (SAC). Nuclei were isolated at various times after stimulation with SAC. Stimulation with SAC resulted in significant increase in the transcription of all of the genes. Maximum expression of the c-fos, transferrin receptor, DR beta, and DQ beta genes was obtained within 0.5 h after stimulation. Maximum expression of c-myc and Blast-1 was obtained within 3 h. Peak expression of Ig kappa was observed at 8 h. Transcriptional activities of all genes examined, except for the Blast-1 and Ig kappa, decreased rapidly after their respective peaks; they remained at higher levels than their base line. Inhibition of protein synthesis by cycloheximide did not significantly affect the kinetics of transcription of these genes. These data demonstrate the cascade of transcriptional activity of various genes associated with human B cell activation and indicate that the induction of their transcription is independent of de novo protein synthesis.

Antigens, CD↗

Intermittent cyclophosphamide for the treatment of autoimmune thrombocytopenia in systemic lupus erythematosus.

STUDY OBJECTIVE: To determine the effect of monthly intravenous cyclophosphamide therapy in patients with systemic lupus erythematosus and autoimmune thrombocytopenia. DESIGN: Uncontrolled, retrospective clinical study. SETTING: Government referral-based research hospital. PATIENTS: Seven patients with systemic lupus erythematosus and 2 or more months of thrombocytopenia refractory to or requiring excessive doses of corticosteroids. Two patients had also failed to respond to splenectomy and repeated intravenous methylprednisolone infusions. Six patients had severe active renal disease at the time of treatment. INTERVENTIONS: Cyclophosphamide, 0.75 to 1.0 g/m2 body surface area, was given intravenously every month for at least 4 months. Prednisone dose ranged between 0.5 to 1.0 mg/kg.d. MEASUREMENTS AND MAIN RESULTS: All seven patients had normal platelet counts within 2 to 18 weeks after cyclophosphamide treatment (one to four doses). Prednisone was tapered to 0.25 mg/kg on alternate days in all patients. All six patients had significant improvement in their renal disease and lupus serologies. Cyclophosphamide was discontinued after four to six doses in five patients. Four patients maintained normal platelet counts on low dose, alternate-day prednisone for a mean of 5.6 years of follow-up. Two patients had recurrence of thrombocytopenia 1 to 3 years after discontinuing cyclophosphamide. CONCLUSIONS: Monthly intravenous cyclophosphamide is potentially useful for the management of autoimmune thrombocytopenia in patients with systemic lupus erythematosus who are refractory to or dependent on unacceptably high doses of corticosteroids, or are experiencing side effects of conventional medical or surgical treatment.

Autoimmune Diseases↗

c-myc proto-oncogene expression in peripheral blood mononuclear cells from patients with primary Sjögren's syndrome.

We examined peripheral blood mononuclear cells (PBMC) from 16 patients with Sjögren's syndrome (SS) and 7 normal control subjects for the expression of the c-myc proto-oncogene. Patients with SS were found to have a significantly increased expression of c-myc messenger RNA compared with normal individuals. No abnormal forms of c-myc RNA were detected in the SS patients. DNA analysis did not show deletion, rearrangement, or amplification in the c-myc proto-oncogene. The methylation status of the c-myc gene in patients with SS was found to be comparable with that of the control subjects. Nuclear run-off assays showed increased transcription of the c-myc gene in some patients but normal transcription in others, suggesting that posttranscriptional mechanisms are also involved in the increased c-myc messenger RNA observed in these patients. Two patients with primary SS and B cell lymphomas were found to have normal c-myc expression in their PBMC. These results demonstrate the presence of activated PBMC in patients with primary SS and delineate some of the mechanisms that are involved at the molecular level. We speculate that increased c-myc expression may represent an early permissive event in the progression toward neoplasia in these patients.

Gene Amplification↗

Synovitis in angioimmunoblastic lymphadenopathy with dysproteinemia simulating rheumatoid arthritis.

We describe a patient with angioimmunoblastic lymphadenopathy with dysproteinemia who developed a symmetric, rheumatoid-like, peripheral polyarthritis. Radiographs of the involved joints revealed soft tissue swelling without erosions or cartilage loss. Rheumatoid factor and fluorescent antinuclear antibodies were negative, and C-reactive protein and erythrocyte sedimentation rate were normal. Synovial fluid analysis showed an inflammatory effusion (white blood cell count of 3,500/mm3, with 76% polymorphonuclear leukocytes). A closed synovial biopsy of the wrist revealed a mononuclear infiltrate consistent with angioimmunoblastic lymphadenopathy with dysproteinemia. Monthly parenteral chemotherapy treatment with high-dose methyl-prednisolone and cyclophosphamide resulted in remission of all manifestations of disease, including arthritis.

Arthritis, Rheumatoid↗