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N Del Papa

Publications and source records attributed to N Del Papa.

At least 19 recordsLinked to original sources
PubMed2004

Comparison between iloprost and alprostadil in the treatment of Raynaud's phenomenon.

OBJECTIVE: The prostanoids iloprost and alprostadil are widely used to treat ischaemic changes in patients with Raynaud's phenomenon (RP), but the optimal regimen is poorly defined. We evaluated whether there are differences between iloprost and alprostadil, in terms of either clinical efficacy or of laboratory data, with the aim of assisting in the treatment of connective tissue disease (CTD)-associated RP. METHODS: Twenty-one women with CTD-associated RP were given intravenous iloprost (11 patients) or alprostadil (10 patients) cyclically (5 consecutive days, followed by 1 day every 30 days). Clinical efficacy (RP symptoms, skin score, digital ulcers) and circulating levels of von Willebrand factor (VWf), tissue plasminogen activator (tPA), thrombomodulin (TM) and Type III procollagen N-terminal propeptide (PIIINP) were evaluated by enzyme-linked immunoassay at different intervals. RESULTS: The overall benefits of iloprost and alprostadil were similar. RP improved in 45% versus 90% of patients; ulcers in 60% versus 40% of patients (iloprost versus alprostadil). Skin score did not significantly change with either drug. Circulating VWf decreased with either drug (iloprost -6.2%, alprostadil -9.4%), while tPA, TM, and PIIINP remained unchanged. Side effects were only minor and less frequent with alprostadil. CONCLUSION: Iloprost and alprostadil were both of benefit in CTD-associated RP, without significant differences in either clinical efficacy or circulating markers. However, ease of handling and the lower price favours alprostadil.

Adult↗
PubMed2001

Activation of the immune system and coronary artery disease: the role of anti-endothelial cell antibodies.

On the basis of the role of immuno-mediated inflammation in atherosclerosis we investigated, (1) the prevalence of anti-endothelial cell antibodies (AECA) in ischaemic heart disease (IHD); (2) if beta2-glycoprotein I (beta2-GPI) was the target antigen of AECA; (3) the relationship between AECA, tissue factor (TF) and tissue factor pathway inhibitor (TFPI). In 93 consecutive IHD patients undergoing percutaneous transluminal coronary angioplasty (PTCA) and 105 controls AECA were detected by ELISA on human umbilical vein endothelial cells (HUVEC). AECA positive sera were evaluated for anti-beta2-GPI antibodies by ELISA. TF and TFPI plasma levels were assessed by ELISA. Twelve of 93 (12.9%) IHD patients and only one of 105 controls (0.95%) were AECA positive. The prevalence of AECA was higher in unstable angina (UA) than in effort angina (EA) (P=0.01). Three of 12 AECA positive sera resulted positive for anti-beta2-GPI and showed a marked decrease in EC-binding when tested on HUVEC cultured in serum-free medium. The binding was restored by the addition of beta2-GPI. TF and TFPI levels were similar in AECA positive and AECA negative patients. The rate of angiographically documented clinical recurrences was 66.7% in the AECA positive and 14.8% in the AECA negative group (P=0.0004) with a significant relationship between restenosis and AECA (P<0.0001), unchanged by the inclusion of cardiovascular risk factors in the regression model. Our results suggest a 'role' for AECA in the immune-mediated inflammation in UA beta2-GPI is not the only AECA target antigen. AECA are not responsible for high TF and TFPI levels. The high rate of clinical recurrences after PTCA, confirmed by angiography, in AECA positive patients is in line with such a role and suggests further large-scale 'ad hoc' studies.

Angioplasty, Balloon, Coronary↗
PubMed2001

Anti-C1q antibodies may help in diagnosing a renal flare in lupus nephritis.

It is still uncertain which, if any, immunologic parameters may help diagnose a renal flare of lupus nephritis. Anti-C1q antibody (Ab) titers have been elevated in patients with lupus with renal involvement, but little information is available on whether the titers are different in quiescent and active phases of lupus nephritis. In this study, we compared anti-C1q Ab titers with other serological test results in 48 patients with biopsy-proven lupus nephritis to assess which parameter could offer the best reliability for differentiating between quiescent and active phases of lupus nephritis. Serum C3 and C4 levels, as well as anti-double-stranded DNA, antiendothelial cell, anti-C1q, and antiphospholipid Ab titers, were evaluated in patients with quiescent renal disease (38 samples) and those with clinical evidence of renal activity (23 samples). Only anti-C1q Ab titers correlated with active renal disease in both univariate (P < 0.0001) and multivariate analysis (P < 0.0001), with a sensitivity of 87% and a specificity of 92%. In six patients, immunologic parameters were measured serially. In all patients, the high anti-C1q Ab titers returned to normal values after treatment-induced remission. The other serological parameters did not show a significant association with renal disease activity. In patients with biopsy-proven lupus nephritis, anti-C1q Ab titers appear to be strongly related to renal disease activity. Their measurement may be useful for confirming the diagnosis of renal flares of lupus nephritis.

Adult↗
PubMed1999

Antibodies to endothelial cells identify myocardial damage and predict development of coronary artery disease in patients with transplanted hearts.

BACKGROUND: Transplant-induced coronary artery disease is a leading cause of graft failure in cardiac allograft recipients after the first year of transplantation, but there presently is no test to identify patients at high risk for developing the disease. Our research is focused on development of a predictive test to identify patients at high risk of developing the disease. METHODS: Sixty-eight cardiac allograft recipients transplanted and followed at Methodist Hospital between 1982 and 1996 were studied. Serial annual angiograms were used to diagnose coronary artery disease, and serial endomyocardial biopsies were used to detect cellular infiltrates and microvascular disease. Biopsy-matched serum samples were used for cardiac troponin-T determinations as measures of myocardial damage, and serum antibodies to endothelial cells were determined by using flow cytometry, enzyme-linked immunosorbent assay and immunoblotting techniques. The endothelial antibody data were evaluated statistically for associations with angiographic changes, biopsy findings and biochemical evidence of myocardial damage. FINDINGS: Antibodies to endothelial cells were identified by all three techniques, and significant associations were found for the amount of antibody identified by Western immunoblotting with histological rejection grades in biopsies, which were confirmed immunocytochemically as macrophages (p<0.01) and T lymphocytes (P = 0.03). These antibodies also associated significantly with vascular antithrombin depletion (p = 0.02), biochemical evidence of myocardial damage (p = 0.005) and subsequent development of coronary artery disease (p = 0.03). INTERPRETATION: The significant association of anti-endothelial antibodies with cellular infiltrates, depletion of vascular antithrombin and myocardial damage suggests a role for antibody in the development of transplant-induced arteriopathy. The significant association of antiendothelial antibodies with the future development of coronary artery disease further suggests that assessment of these antibodies may provide a non-invasive test to predict the development of transplant-induced coronary artery disease.

Adult↗
PubMed1999

Anti-endothelial cell IgG fractions from systemic lupus erythematosus patients bind to human endothelial cells and induce a pro-adhesive and a pro-inflammatory phenotype in vitro.

Affinity purified immunoglobulin G (IgG) fractions from systemic lupus erythematosus (SLE) patients positive for anti-endothelial cell antibodies (AECA) bind human umbilical vein endothelial cell (HUVEC) monolayers. In vitro incubation of serial protein concentrations of SLE AECA IgG induces a dose-dependent endothelial activation: i) increase of functional adhesion of the monocytic cell line U937; ii) upregulation of E-Selectin, ICAM-1, VCAM-1 expression evaluated by a cell solid-phase enzyme linked immunoassay; and iii) increased secretion of interleukin (IL)-6 in the culture supernatants. Control experiments carried out with HUVEC monolayers incubated with IgG fractions from normal healthy controls or from AECA negative SLE sera do not affect at all endothelial adhesion molecule expression or pro-inflammatory cytokine secretion. The AECA IgG effects are not related to both anti-phospholipid or anti-DNA activities. Taken together the findings suggest that these autoantibodies might be important in recruiting and in activating mononuclear leukocytes responsible for vessel wall infiltration and raise the possibility that AECA might display a pathogenic role in SLE vessel damage.

Adult↗
PubMed1998

Human beta 2-glycoprotein I binds to endothelial cells through a cluster of lysine residues that are critical for anionic phospholipid binding and offers epitopes for anti-beta 2-glycoprotein I antibodies.

Beta 2-Glycoprotein I (beta 2GPI) is a phospholipid-binding protein recognized by serum autoantibodies from the anti-phospholipid syndrome both in cardiolipin- and beta 2GPI-coated plates. We found that: 1) recombinant wild-type beta 2GPI bound to HUVEC and was recognized by both human monoclonal IgM and affinity-purified polyclonal IgG anti-beta 2GPI anti-phospholipid syndrome Abs; and 2) a single amino acid change from Lys286 to Glu significantly reduced endothelial adhesion. Double and triple mutants (from Lys284,287 to Glu284,287, from Lys286,287 to Glu286,287, and from Lys284,286,287 to Glu284,286,287) completely abolished endothelial binding. A synthetic peptide (P1) spanning the sequence Glu274-Cys288 of the beta 2GPI fifth domain still displayed endothelial adhesion. Another peptide (P8), identical with P1 except that Cys281 and Cys288 were substituted with serine residues, did not bind to HUVEC. Anti-beta 2GPI Abs, once bound to P1 adhered to HUVEC, induced E-selectin expression and up-regulated IL-6 secretion. Control experiments conducted with irrelevant Abs as well as with the P8 peptide did not show any endothelial Ab binding nor E-selectin and IL-6 modulation. Our results suggest that: 1) beta 2GPI binds to endothelial cells through its fifth domain; 2) the major phospholipid-binding site that mediates the binding to anionic phospholipids is also involved in endothelial binding; 3) HUVEC provide a suitable surface for beta 2GPI binding comparable to that displayed by anionic phospholipids dried on microtiter wells; and 4) the formation of the complex between beta 2GPI and the specific Abs leads to endothelial activation in vitro.

Amino Acid Sequence↗
PubMed1998

Anti-mitochondrial M5 type antibody represents one of the serological markers for anti-phospholipid syndrome distinct from anti-cardiolipin and anti-beta2-glycoprotein I antibodies.

The aim of this study was to characterize the antigen specificity and to evaluate the diagnostic and prognostic value of anti-mitochondrial M5 type antibodies (AMA M5). Fifty-eight patients selected on the basis of their AMA M5 positivity were investigated in relationship to their clinical and serological profile. Cross-absorption studies, Western blotting and immunoprecipitation analysis were carried out for AMA M5 antigen specificity characterization. Most patients had a diagnosis of systemic lupus erythematosus (SLE) (65.5%) or of primary anti-phospholipid syndrome (PAPS) (24%); all the patients were positive for IgG or IgM anti-cardiolipin (anti-CL) antibodies and 49% of them also displayed lupus anticoagulant (LA) activity. Anti-beta2-glycoprotein I (beta2-GPI) IgG were detectable in 30/38 sera (78.9%) and IgM in 34/38 (89.4%). While anti-CL and anti-beta2-GPI IgG antibodies were significantly associated with history of thrombosis and fetal loss, AMA M5 displayed a statistical association only for thrombocytopenia and recurrent fetal loss. Absorption with human beta2-GPI both in free solution or in solid phase as well as with CL liposomes or CL/beta2-GPI liposome complexes did not affect AMA M5 fluorescence. While AMA M5 activity is absorbed by whole mitochondrial preparations, no specific reactivities against several human, bovine and rat mitochondrial proteins could be detected in Western blotting and immunoprecipitation studies. AMA M5 appear to be detectable in both primary and secondary APS, displaying a strong association with the presence of thrombocytopenia and fetal loss. Although strictly related to anti-phospholipid antibodies, AMA M5, anti-CL and anti-beta2-GPI antibodies represent distinct serological markers of the APS.

Adolescent↗
PubMed1998

Antibody to carbonic anhydrase II is present in primary biliary cirrhosis (PBC) irrespective of antimitochondrial antibody status.

Antibody to carbonic anhydrase II, an enzyme abundantly present in biliary epithelium, has been proposed as a diagnostic marker for antimitochondrial antibody-negative PBC. In this study we determine its prevalence and clinical significance in a large series of patients with antimitochondrial antibody-positive and -negative PBC. Reactivity to carbonic anhydrase II was sought by Western immunoblotting in sera from 215 consecutive patients with PBC (26 antimitochondrial antibody-negative), 13 with autoimmune hepatitis, 25 with primary Sjögren's syndrome (pSS), 12 with systemic sclerosis, 19 with systemic lupus erythematosus and 73 healthy subjects. The prevalence of antibody to carbonic anhydrase II (titre 1:100) in PBC was 8%. No specific reactivity to carbonic anhydrase II was found in antimitochondrial antibody-negative PBC (7% versus 8% in antimitochondrial antibody-positive PBC). Ascites (P = 0.006) and Sjögren's syndrome (SS) (P = 0.022) in PBC were significantly associated with presence of the antibody. In patients with SS associated with PBC, the prevalence (19%) was similar to that observed in pSS (16%). At a serum dilution of 1:40, the prevalence of positive sera in PBC rose to 27% but disease specificity was reduced. Our findings in a large population of PBC patients rule out a relation between presence of antibody to carbonic anhydrase II and lack of antimitochondrial antibody. The higher prevalence of ascites found in positive patients warrants further evaluation.

Adult↗
PubMed1998

Characterization of murine monoclonal anti-endothelial cell antibodies (AECA) produced by idiotypic manipulation with human AECA.

The IgG fraction of human anti-endothelial cell antibodies (AECA) obtained from a patient with Wegener's granulomatosis was used as immunogen to raise AECA mAb in mice selected among those which developed vasculitis-like lesions after immunization. Three mAb (BGM, 3C8 and 7G2), selected by cyto-ELISA and flow cytometry analyses, featured a specific reactivity with human umbilical vein endothelial cells (HUVEC) and the mouse endothelial cell line H5V; on the contrary, HEp2 cells, the murine melanoma B16 cell line, the extracellular matrix as well as several other antigens tested were not recognized. BGM mAb, an IgG3 precipitating a 70 kDa structure from HUVEC, was able to induce endothelial cells to secrete amounts of IL-6 significantly higher than irrelevant controls or mAb binding different endothelial antigens (i.e. CD31, CD29, ICAM-1 and HLA class I). BGM mAb induced significant levels of antibody-dependent cell cytotoxicity (13 +/- 2.5 versus 0.6 +/- 0.03%). To the best of our knowledge, BGM is the first murine mAb specific for human endothelial cells generated by idiotypic manipulation; secondly, its biological properties further support the notion of a pathogenic role for AECA in autoimmune-mediated diseases.

Animals↗
PubMed1998

Beta2-glycoprotein I as a 'cofactor' for anti-phospholipid reactivity with endothelial cells.

Beta2-glycoprotein I (beta2GPI) is a cofactor for anti-phospholipid (aPL) binding to cardiolipin (CL)-coated plates. Beta2GPI is also able to bind to endothelial cell (EC) membranes as supported by in-vivo as well as by in-vitro studies. The PL-binding site in the fifth domain of the molecule is involved in the adhesion to endothelium. Actually, specific mutations in this molecular portion abolish endothelium binding and a synthetic peptide spanning the sequence Glu274-Cys288 of the CL-binding site displays comparable adhesion to EC monolayers. Heparan sulphate appears to be one of the anionic EC membrane structures with which cationic beta2GPI interacts, as supported by studies with heparitinase-treated EC. Beta2GPI binding to EC might be related to its activity as endothelial growth factor or as a lipid-carrying glycoprotein. Adhesion of beta2GPI to endothelial membranes offers suitable epitopes for circulating aPL that, once bound, can induce cell activation

Amino Acid Substitution↗
PubMed1997

Endothelial cells as target for antiphospholipid antibodies. Human polyclonal and monoclonal anti-beta 2-glycoprotein I antibodies react in vitro with endothelial cells through adherent beta 2-glycoprotein I and induce endothelial activation.

OBJECTIVE: To investigate the ability of human anti-beta 2-glycoprotein I (anti-beta 2 GPI) antibodies to recognize the cofactor adherent on endothelial cells (EC) and to modulate endothelial functions. METHODS: Six human affinity-purified polyclonal anti-beta 2 GPI IgG and 2 IgM monoclonal antibodies (MAb) were obtained from patients with the antiphospholipid syndrome. The antibodies were tested for their ability to 1) bind to endothelial monolayers through the adherent beta 2 GPI and 2) modulate endothelial adhesion molecule expression and interleukin-6 (IL-6) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) secretion. RESULTS: The affinity-purified IgG and the MAb with anti-beta 2 GPI activity, but not the respective controls, displayed EC binding, which declined on cells incubated in serum-free medium and was restored in a dose-dependent manner by exogenous human beta 2 GPI. After EC binding, both polyclonal and monoclonal antibodies up-regulated adhesion molecule expression. Anti-beta 2 GPI MAb also significantly increased IL-6 and 6-keto-PGF1 alpha secretion. CONCLUSION: These findings support the hypothesis that anti-beta 2 GPI antibodies bind and activate EC through the adherent cofactor beta 2 GPI, likely leading to a procoagulant state.

6-Ketoprostaglandin F1 alpha↗
PubMed1997

Endothelial cells as a target for antiphospholipid antibodies: role of anti-beta 2 glycoprotein I antibodies.

PROBLEM: To investigate the role of the plasma cofactor for antiphospholipid antibodies in antibody binding to endothelial cells. METHOD OF STUDY: a) Evaluation of endothelial cell binding of polyclonal and monoclonal anti-beta 2 glycoprotein I antibodies; and b) study of the effects of antibody binding: adhesion molecule expression, leukocyte adhesion, and interleukin-1 beta secretion. RESULTS: Anti-beta 2 glycoprotein I antibodies bind endothelial cell monolayers in vitro by reacting with the cofactor adhered to the cell membranes. Antibody binding induces an up-regulation of adhesion molecules, favours leukocyte adherence, and increases interleukin-1 beta secretion. Interleukin-1 beta plays an active role to mediate adhesion molecule expression through an autocrine loop, as shown by the inhibitory effect of interleukin 1 receptor antagonist. CONCLUSIONS: Antiphospholipid antibodies do react with endothelium through the co-factor adhered to their cell membranes and induces a pro-adhesive cell phenotype.

Animals↗
PubMed1997

Differential risk of non-Hodgkin's lymphoma in Italian patients with primary Sjögren's syndrome.

OBJECTIVE: To assess the incidence of non-Hodgkin's lymphoma (NHL) and estimate the relative risk (RR) of developing lymphoproliferative complications in a large population of Italian patients with Sjögren's syndrome (SS) and to ascertain if any difference exists between the north and centre-south of Italy. METHODS: Differential relative risks of NHL were obtained by comparing the number of observed cases with cases identified on the basis of age-sex-time specific incidence rates extracted from regional cancer registries. RESULTS: Among the 331 patients with SS studied, 9 cases of NHL occurred, while no lymphoid malignancy appeared in patients with overlapping connective tissue disease (secondary SS) or in males with primary SS. As the number of NHL cases identified on the basis of the rate in the cancer registries would have been 0.27, the RR is 33.3 (p < 0.001). The incidence rate of NHL in Italian patients with SS is about 5.1/1000 person-years. 5.4/1000 per year in the north of the country and 4.8/1000 per year in the centre-south. The relative risks are, respectively, 34.7 and 32.5. CONCLUSION: Italian patients with primary SS have increased risk of developing NHL. In this group, the absence of a significant difference between the north and the centre-south of Italy contrasts with the higher incidence of NHL in the general population of northern regions and strengthens the direct connection between primary SS and NHL.

Adult↗
PubMed1996

Immunosuppressive activity of 15-deoxyspergualin on normal and autoimmune peripheral blood mononuclear cells.

Several experimental conditions were used in this study to evaluate the in vitro effects of 15-deoxyspergualin on the function of T lymphocytes, B lymphocytes and monocytes from healthy subjects and patients suffering from systemic lupus erythematosus. Whilst the secretion of polyclonal immunoglobulin (Ig) M and IgG from the B lymphocytes of the healthy subjects was diminished by 15-deoxyspergualin, neither the proliferative response of normal T and B cells to mitogenic stimulation nor the cytokine secretory capacity of these cells (e.g. interleukin-2, -4, -6 and gamma-interferon) and monocytes (e.g. interleukin-1 beta and -6) were affected by the drug. In contrast, on the mononuclear cells obtained from the lupus patients not only did 15-deoxyspergualin inhibit the spontaneous production of polyclonal and anti-DNA IgG antibodies but also suppressed interleukin-1 beta secretion from the monocytes. Other functional responses of T and B cells and monocytes from lupus patients, including mitogenic activation and cytokine secretion, were not altered by the drug. These data suggest that 15-deoxyspergualin possesses a novel mechanism of pharmacological immunosuppression apparently different from that of other immunosuppressants, such as cyclosporin A, FK506 and corticosteroids, that seems to be primarily displayed at the level of autoreactive B cells and monocytes.

Cytokines↗
PubMed1996

Pathogenic role of anti-endothelial cell antibodies in vasculitis. An idiotypic experimental model.

Idiotypic manipulation of naive mice has previously been used for induction of systemic autoimmune diseases (e.g., antiphospholipid syndrome, systemic lupus erythematosus, and Wegener's granulomatosis). The aim of this study focused on the utilization of this technique to induce the production of anti-endothelial cells Abs (AECA) and autoimmune vasculitis in a murine model. AECA were derived from a Wegener's granulomatosis patient's plasma. IgG was purified by absorption on a proteinase-3 affinity column resulting in the depletion of anti-neutrophil cytoplasmic Ab activity. The absorbed IgG fraction displayed a high titer of AECA as evidenced by a cyto-ELISA against unfixed human umbilical vein endothelial cells. BALB/c mice were actively immunized with the purified AECA. Three months after a boost injection with the human AECA, mice developed endogenous AECA (AB), but not Abs to proteinase-3, cardiolipin, or DNA. Histologic examination of lungs and kidneys revealed both lymphoid cell infiltration surrounding arterioles and venules; as well as deposition of Igs at the outer part of blood vessel walls. This experimental animal model of vasculitis, a product of our method of idiotypic manipulation, provides the first direct proof for the pathogenicity of AECA.

Animals↗