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Dimitrios T Boumpas

Publications and source records attributed to Dimitrios T Boumpas.

12 recordsLinked to original sources
PubMed2005

Biological therapies of autoimmune diseases.

The advances in the understanding of the pathogenesis of the autoimmune diseases have led to new treatment targets. Biological agents enhance or replace conventional immunosuppressive therapies in the treatment of autoimmune diseases. TNF-alpha has been validated as a good treatment target but the potential modalities also include the inhibition of the interaction between LFA-3 (lymphocyte function-associated antigen 3) and CD2, the blockade of the IL-1 receptors, the antibodies against the alpha4 integrins, the antibodies against B-cell CD20 and the inhibition of the activation of T-cells. The new treatments have had a major impact on inflammatory symptoms, the radiological damage and the anemia of chronic disease in rheumatoid arthritis and have substantially controlled the signs and symptoms in the spondylarthropathies group and plaque-type psoriasis. The efficacy of the biologic agents in systemic lupus erythematosus warrants further investigation but there have been some promising results in proliferative lupus nephritis. Several small studies have explored their use in the treatment of Sjogren's syndrome, adult onset Still's disease and several vasculitides but the results are still preliminary and warrant confirmation. The efficacy of the biological agents has been impressive. Susceptibility to infections has always been a major concern; a high level of suspicion is necessary and strategies should be implemented for the prevention, the rapid identification and pre-emptive therapy of such infections.

Animals↗
PubMed2004

Cytochrome P450 pharmacogenetics as a predictor of toxicity and clinical response to pulse cyclophosphamide in lupus nephritis.

OBJECTIVE: Pulse cyclophosphamide is the treatment of choice for severe lupus nephritis. However, not all patients respond to this therapy, and gonadal toxicity is of particular concern. Cyclophosphamide is a prodrug that requires activation by cytochrome P450 (CYP) enzymes. We conducted a retrospective cohort study to test whether genetic polymorphisms of these enzymes are associated with the toxicity of, and clinical response to, cyclophosphamide in patients with lupus nephritis. METHODS: Sixty-two patients with proliferative lupus nephritis treated with cyclophosphamide were genotyped for common variant alleles of CYP2B6, 2C19, 2C9, and 3A5. We examined the association between these genotypes and the following clinical end points: development of premature ovarian failure, end-stage renal disease (ESRD), doubling of serum creatinine level, and achievement of complete renal response. RESULTS: The observed frequencies of the variant alleles CYP2B6*5, CYP2C19*2, CYP2C9*2, and CYP3A5*3 were 12.1%, 25.0%, 4.0%, and 75.8%, respectively. Patients who were either heterozygous or homozygous for CYP2C19*2 had a significantly lower risk of developing premature ovarian failure (relative risk 0.10; 95% confidence interval 0.02-0.52), after adjustment for age and total number of cyclophosphamide pulses received. In a survival analysis, patients homozygous for CYP2B6*5 (n = 3) or CYP2C19*2 (n = 4) had a higher probability of reaching ESRD (P = 0.0005) and of doubling the creatinine level (P = 0.0005) as well as a trend toward a lower probability of achieving a complete renal response (P = 0.051). CONCLUSION: Determination of selected cytochrome P450 enzyme genotypes may be valuable for predicting the risk of premature ovarian failure in lupus nephritis patients treated with cyclophosphamide. The association of these genotypes with renal response needs further validation.

Adult↗
PubMed2004

Autoimmune hepatitis: evolving concepts.

The liver is continuously exposed to a large antigenic load that includes pathogens, toxins, tumor cells and dietary antigens. A loss of tolerance against its own antigens may result in autoimmune hepatitis (AIH). The current paradigm holds that the disease is the result of self-perpetuating autoimmune process triggered by yet unknown factors (infections, chemicals, drugs) in a genetically susceptible host. To date, several putative hepatocellular surface antigens have been identified: P450-IID6 (recognized by the anti-LKM-1 autoantibodies) a membrane bound asialoglycoprotein receptor (a liver-specific membrane protein), a cytosolic UGA-suppressor tRNA associated protein (recognized by anti-SMA and anti-LP antibodies) and argininosuccinate lysate and formiminotransferase cyclodeaminase (recognized by ant-LC1 antibodies). In contrast to other chronic hepatitides patients with AIH display significant T cell hypereactivity to autologous liver antigens. Tissue injury seems to be mediated by CD4+ or CD8+ T cells and/or by antibody-dependent cell mediated cytotoxicity.

Ammonia-Lyases↗
PubMed2004

Intestinal ischemia as the first manifestation of vasculitis.

OBJECTIVE: To summarize current knowledge regarding the diagnosis and management of gastrointestinal vasculitis. METHODS: Three cases of gastrointestinal vasculitis with acute abdominal ischemia as their first manifestation are presented. Underlying diseases were microscopic polyangiitis, systemic lupus erythematosus (SLE), and polyarteritis nodosa (PAN). Relevant English-language articles collected from the PubMed database were reviewed. RESULTS: Among the angiitides, PAN, SLE, and Henoch-Schönlein are those most commonly accompanied by gastrointestinal complications. Intestinal vasculitis usually occurs when there is evidence of generalized disease activity. Abdominal computerized tomography is a valuable tool for diagnosing intestinal ischemia and suspected vasculitis. CONCLUSIONS: In young patients presenting with intestinal ischemia, it is essential to assess the possibility of an underlying systemic disease. With prompt initiation of immunosuppressive treatment, surgery may be avoided. Prognosis is improved when there is minimal delay in surgical intervention.

Abdomen, Acute↗
PubMed2003

A short course of BG9588 (anti-CD40 ligand antibody) improves serologic activity and decreases hematuria in patients with proliferative lupus glomerulonephritis.

OBJECTIVE: CD40-CD40 ligand (CD40L) interactions play a significant role in the production of autoantibodies and tissue injury in lupus nephritis. We performed an open-label, multiple-dose study to evaluate the safety, efficacy, and pharmacokinetics of BG9588, a humanized anti-CD40L antibody, in patients with proliferative lupus nephritis. The primary outcome measure was 50% reduction in proteinuria without worsening of renal function. METHODS: Twenty-eight patients with active proliferative lupus nephritis were scheduled to receive 20 mg/kg of BG9588 at biweekly intervals for the first 3 doses and at monthly intervals for 4 additional doses. Safety evaluations were performed on all patients. Eighteen patients receiving at least 3 doses were evaluated for efficacy. RESULTS: The study was terminated prematurely because of thromboembolic events occurring in patients in this and other BG9588 protocols (2 myocardial infarctions in this study). Of the 18 patients for whom efficacy could be evaluated, 2 had a 50% reduction in proteinuria without worsening of renal function. Mean reductions of 38.9% (P < 0.005), 50.1% (P < 0.005), and 25.3% (P < 0.05) in anti-double-stranded DNA (anti-dsDNA) antibody titers were observed at 1, 2, and 3 months, respectively, after the last treatment. There was a significant increase in serum C3 concentrations at 1 month after the last dose (P < 0.005), and hematuria disappeared in all 5 patients with significant hematuria at baseline. There were no statistically significant reductions in lymphocyte count or serum immunoglobulin, anticardiolipin antibody, or rubella IgG antibody concentrations after therapy. CONCLUSION: A short course of BG9588 treatment in patients with proliferative lupus nephritis reduces anti-dsDNA antibodies, increases C3 concentrations, and decreases hematuria, suggesting that the drug has immunomodulatory action. Additional studies will be needed to evaluate its long-term effects.

Adjuvants, Immunologic↗
PubMed2003

Monocyte response to Th1 stimulation and effector function toward human mesangial cells are not impaired in patients with lupus nephritis.

Monocytes/macrophages activated by Th1 stimulation such as interferon-gamma (IFN-gamma) and CD40 ligand (CD40L) infiltrate the kidney and play a critical role in the progression of lupus nephritis (LN). We examined the monocyte response to Th1 stimulation and their effector function toward activating renal resident cells in patients with LN. Following stimulation with IFN-gamma granulocyte macrophage-colony stimulating factor (GM-CSF)/recombinant CD40L the production of tumor necrosis factor-alpha and IL-12 p70 by PBMC was significantly higher in LN patients. In coculture experiments employing activated monocytes and human mesangial cells, there was a trend toward higher monocyte chemoattractant protein-1 production by lupus monocytes compared to normal controls. Basal expression of CD40, ICAM-1, and STAT-1 was significantly higher in monocytes from LN patients, suggesting ongoing activation. Monocyte response to IFN-gamma, as accessed by intercellular adhesion molecule-1 upregulation and phosphorylation of STAT-1, was comparable between the two groups. Thus, in contrast to earlier reports, Th1-dependent monocyte activation is not impaired. In this disease activated monocytes appear to be fully capable of inducing renal injury.

Adult↗
PubMed2003

Transfusion-associated GVHD after fludarabine therapy in a patient with systemic lupus erythematosus.

BACKGROUND: Fludarabine, a purine antimetabolite with potent immunosuppressive properties, has previously been associated with the development of transfusion-associated GVHD (TA-GVHD) in patients with hematologic malignancies. Its role as a risk factor for TA-GVHD in patients without underlying leukemia or lymphoma is uncertain. STUDY DESIGN AND METHODS: A 42-year-old female with refractory lupus nephritis received three monthly cycles of fludarabine (30 mg/m2/day on Days 1-3) and cyclophosphamide (500 mg/m2 on Day 1). Three months after the last dose of fludarabine, she received 2 units of packed RBCs and 6 units of pooled random platelets, none of which were irradiated. Two weeks later, fever, rash, aminotransferase elevations, hyperbilirubinemia, and pancytopenia developed. RESULTS: Marrow biopsy showed severe aplasia and skin biopsy was consistent with GVHD. Allele-level HLA typing on circulating lymphocytes revealed extra HLA alleles not present in her pretreatment sample, but identical to the HLA haplotypes of an unrelated platelet donor. Treatment with antithymocyte globulin, cyclosporine, and prednisone was followed by preparatory conditioning for a PBPC transplant from an HLA-identical sibling, but the patient died of disseminated candidiasis before transplant. CONCLUSIONS: Fludarabine and other purine analogs are increasingly used in the treatment of disorders other than hematologic malignancy, such as autoimmune disease. The occurence of TA-GVHD after fludarabine therapy in a patient with lupus strongly suggests that this drug is sufficiently immunoablative to be an independent risk factor for TA-GVHD. Irradiation of blood components should be considered in all patients who receive fludarabine therapy.

Adult↗
PubMed2002

Anemia of chronic disease in rheumatoid arthritis is associated with increased apoptosis of bone marrow erythroid cells: improvement following anti-tumor necrosis factor-alpha antibody therapy.

Circumstantial evidence has implicated tumor necrosis factor alpha (TNF-alpha) in the pathogenesis of anemia of chronic disease (ACD) in rheumatoid arthritis (RA). We investigated the role of TNF-alpha in erythropoiesis of patients with active RA (n = 40) and the effect of anti-TNF-alpha antibody administration (cA2). Patients with RA had lower numbers of CD34+/CD71+ and CD36-/glycophorin A+ (glycoA+) bone marrow (BM) cells and increased proportions of apoptotic cells within the CD34+/CD71+ and CD36+/glycoA+ cell compartments, compared to healthy controls (n = 24). Erythroid burst-forming units (BFU-Es) obtained by BM mononuclear or purified CD34+ cells were significantly lower in RA patients compared to controls. These abnormalities were more pronounced among patients with ACD. Increased TNF-alpha levels in patient long-term BM culture supernatants inversely correlated with BFU-Es and hemoglobin levels and positively with the percentage of apoptotic CD34+/CD71+ and CD36+/glycoA+ cells. Following cA2 therapy, a normalization was documented in the number of CD34+/CD71+ and CD36-/glycoA+ cells, the number of BFU-Es, and the proportion of apoptotic CD34+/CD71+ and CD36+/glycoA+ cells, which was associated with a significant increase in hemoglobin levels compared to baseline. Recovery from anemia was more prominent in patients with ACD. The exogenous addition of an anti-TNF-alpha antibody in the cultures increased BFU-E number in patients prior to cA2 treatment but not after treatment, further substantiating the inhibitory role of TNF-alpha on patients' erythropoiesis. We conclude that TNF-alpha-mediated apoptotic depletion of BM erythroid cells may account for ACD in RA and that cA2 administration may ameliorate ACD in these patients by down-regulating the apoptotic mechanisms involved in erythropoiesis.

Adolescent↗
PubMed2002

Bone marrow progenitor cell reserve and function and stromal cell function are defective in rheumatoid arthritis: evidence for a tumor necrosis factor alpha-mediated effect.

Based on previous reports for impaired hematopoiesis in rheumatoid arthritis (RA), and in view of the current interest in exploring the role of autologous stem cell transplantation (ASCT) as an alternative treatment in patients with resistant disease, we have evaluated bone marrow (BM) progenitor cell reserve and function and stromal cell function in 26 patients with active RA. BM progenitor cells were assessed using flow cytometry and clonogenic assays in short-term and long-term BM cultures (LTBMCs). BM stroma function was assessed by evaluating the capacity of preformed irradiated LTBMC stromal layers to support the growth of normal CD34(+) cells. We found that RA patients exhibited low number and increased apoptosis of CD34(+) cells, defective clonogenic potential of BM mononuclear and purified CD34(+) cells, and low progenitor cell recovery in LTBMCs, compared with healthy controls (n = 37). Patient LTBMC stromal layers failed to support normal hematopoiesis and produced abnormally high amounts of tumor necrosis factor alpha (TNF alpha). TNF alpha levels in LTBMC supernatants inversely correlated with the proportion of CD34(+) cells and the number of colony-forming cells, and positively with the percentage of apoptotic CD34(+) cells. Significant restoration of the disturbed hematopoiesis was obtained following anti-TNF alpha treatment in 12 patients studied. We concluded that BM progenitor cell reserve and function and BM stromal cell function are defective in RA probably due, at least in part, to a TNF alpha-mediated effect. The role of these abnormalities on stem cell harvesting and engraftment in RA patients undergoing ASCT remains to be clarified.

Adult↗
PubMed2002

Human platelets stimulate mesangial cells to produce monocyte chemoattractant protein-1 via the CD40/CD40 ligand pathway and may amplify glomerular injury.

Platelets are thought to play an important role in the initiation and the progression of a variety of glomerulonephritides. This study examined whether platelets induce production of monocyte chemoattractant protein-1 (MCP-1), a chemokine involved in leukocyte recruitment and glomerular injury, by cultured human mesangial cells (MC). To this end, platelets isolated from normal human donors were cocultured with MC at various ratios. MCP-1 synthesis was evaluated by quantitative real-time PCR and enzyme-linked immunosorbent assay. Platelets at 1:100 ratio (MC to platelets) induced an approximately 20-fold increase in mesangial MCP-1 mRNA and protein expression through an obligatory cell-to-cell contact-dependent mechanism. Importantly, blockade of the CD40/CD40 ligand (CD40L) pathway with neutralizing antibodies decreased MCP-1 production by approximately 60%. It was confirmed that CD40 was functionally expressed on MC. Gel-shift assays and inhibitors of phosphorylation were used to demonstrate that activation of p38 mitogen-activated protein kinase, protein tyrosine kinases, and nuclear factor-kappa B activation were essential for MCP-1 production. These data indicate that platelet/MC contact stimulates the production of MCP-1 and may contribute to glomerular inflammatory responses by recruiting leukocytes from the peripheral blood.

Blood Platelets↗
PubMed2002

Gelatinase expression and activity in the synovium and skin of patients with erosive psoriatic arthritis.

OBJECTIVE: Matrix metalloproteinases (MMP), especially the gelatinases (MMP2, MMP9), have been implicated in several features of inflammatory arthritis including angiogenesis and bone erosions. We examined the expression and activity of the gelatinases and their regulators in psoriatic skin and synovium using tissue immunohistochemistry and a sensitive tissue based zymographic technique. METHODS: Lesional and perilesional skin biopsies and synovial samples obtained by closed needle biopsy from 15 patients with erosive psoriatic arthritis (PsA) were analyzed by immunohistochemistry for the expression of the gelatinases and their regulators, tissue inhibitor of metalloproteinase 1 and 2 (TIMP-1, TIMP-2) and membrane type metalloproteinases (MTI-MMP. MT2-MMP), using immunohistochemistry. Synovial tissue from 8 patients with erosive rheumatoid arthritis (RA) was used as a comparison. MMP tissue expression was quantified by 2 blinded independent observers. Immunohistochemical data are reported as the mean percentage positive cells per total nucleated cells in 10 high power fields +/- SD. Functional activity of the gelatinases was measured using a sensitive tissue based zymography technique and corrected for protein content. Zymography data are presented as ng/mg +/- SE. RESULTS: MMP expression was greater in the synovial lining layer (LL) than in the synovial sublining layer (SL) in both PsA and RA tissue for most MMP except collagenase I (MMPI), which was equally distributed between the LL and SL. Expression of MMP or their regulators did not differ between PsA synovial membrane (SM) and RA SM in LL. Moreover, although latent gelatinase A (MMP2) staining in PsA SM was equivalent to RA SM, increased gelatinase A activity was found in PsA SM over RA SM using zymography L82.4 (SD 62.8) vs 10.1 (SD 1.7); p = 0.02]. Compared to PsA SM, lesional skin had lower levels of MT1-MMP (MMP14) (1.4 +/- 1.7 vs 15.7 +/- 8.4; p = 0.009) and MT2-MMP (MMP15) (12.1 +/- 8.7 vs 21.6 +/- 9.9; p = 0.001). CONCLUSION: We characterized the expression and activity of gelatinases in PsA and demonstrate that gelatinase activity in SM of PsA patients with erosive disease is comparable to if not greater than that in RA synovium.

Adult↗