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Biomedical subjects

A Amoroso

Publications and source records attributed to A Amoroso.

At least 73 records · Page 4Linked to original sources
PubMed1998

Are HLA class II and immunoglobulin constant region genes involved in the pathogenesis of mixed cryoglobulinemia type II after hepatitis C virus infection?

BACKGROUND/AIMS: Hepatitis C virus infection is known to play an important role in the pathogenesis of essential mixed cryoglobulinemia type II. Progression of hepatitis C virus infection to mixed cryoglobulinemia may be influenced by host immune response. To analyze the immunogenetic background of mixed cryoglobulinemia, we studied HLA-DR, DQ loci and the switch regions of immunoglobulin heavy chain gamma1 and gamma4 constant genes. METHODS: HLA typing was performed in 84 hepatitis C virus-infected patients (46 with cryoglobulins and 38 without), and 109 healthy controls, through analysis of restriction fragment length polymorphisms, supplemented with other techniques. Immunoglobulin heavy chain gamma1 and gamma4 polymorphisms, detected by restriction fragment length polymorphisms, were studied in 41 patients with mixed cryoglobulinemia and 51 controls. RESULTS: The gene frequency of DRB1*11 was significantly higher in patients with mixed cryoglobulinemia than in controls (0.36 and 0.20, respectively; p= 0.0035). However, DRB1*11 was also increased in the subgroup of patients without mixed cryoglobulinemia who did not develop severe liver disease, while it was decreased in those with severe liver damage (0.50 and 0.13; p=0.0035). The frequency of 5.4 kb allele of the immunoglobulin heavy chain gamma1 switch region was higher in patients with mixed cryoglobulinemia than in controls (0.47 and 0.22; pc=0.002), while the frequency of 5.5 kb allele was lower (0.51 and 0.78; pc= 0.001). CONCLUSIONS: Susceptibility to develop cryoglobulins after hepatitis C virus infection was not associated with HLA-DR or DQ. HLA-DRB1*11-positive individuals were protected from serious chronic liver disease after hepatitis C virus infection. Immunoglobulin heavy chain constant gamma1 switch region restriction fragment length polymorphisms were associated with mixed cryoglobulinemia.

Adult↗
PubMed1998

Antineutrophil cytoplasmic antibodies in autoimmune thyroid disorders.

Different antibodies against both organ- and non-organ-specific autoantigens have been found in patients with autoimmune thyroid diseases. The aim of our study was to evaluate the presence of antineutrophil cytoplasmic antibodies (ANCA) in sera of patients affected by Graves' disease (GD) and Hashimoto's thyroiditis (HT). These antibodies were investigated by indirect immunofluorescence; the reactivity against myeloperoxidase and lactoferrin was assessed by ELISA. ANCA were detected by immunofluorescence in 28.5% of patients with GD and 9% of patients with HT. Anti-lactoferrin antibodies were found in 3 of 21 (14.2%) patients affected by GD and in 2 of 11 (18.1%) cases of HT. Anti-myeloperoxidase antibodies were detected only in one (4.7%) patient with GD.

Adult↗
PubMed1998

Autosomal dominant medullary cystic disease: a disorder with variable clinical pictures and exclusion of linkage with the NPH1 locus.

BACKGROUND: The nephronophthisis-medullary cystic disease (NPH/MCD) complex represents a heterogeneous group of hereditary tubulointerstitial nephritis. The most common variant is juvenile recessive NPH, for which a gene locus (NPH1) has been mapped on chromosome 2q13. MCD is a less common dominant condition usually recognized later in life, which resembles NPH in many aspects, still presenting remarkable clinical differences. Nothing is known about the chromosome locus of MCD. METHODS: Five MCD families were studied. Diagnosis was made by inference from family history, type of inheritance, clinical signs and histology. Multipoint linkage analysis was performed by markers D2S293, D2S340 and D2S160 spanning the entire NPH1 locus. RESULTS: Diagnosis of MCD was made in 28 affected members (16 males; 12 females), belonging to five families. Histological diagnosis was available in 10 patients; clinical diagnosis in 11; seven deceased relatives had diagnosis of chronic nephritis. The age at diagnosis ranged from 8 to 65 years. Renal medullary cysts were found in a minority of patients. In family 1, the disease was associated with hyperuricaemia and gouty arthritis. Progression of renal disease presented intra- and extra-family variability with members of the same family showing mild elevation of creatinine or terminal renal failure. The NPH1 locus associated to recessive NPH was excluded from linkage to the dominant MCD. CONCLUSIONS: MCD might be more common than previously assumed. Variability in clinical presentation and absence of histopathological hallmarks contribute to make the diagnosis uncommon. The most remarkable clinical difference with NPH is the age of onset in some kindreds and a delayed progression towards renal failure. The exclusion of linkage to the NPH1 locus suggests the existence of an MCD responsible locus, still to be mapped.

Adolescent↗
PubMed1998

Polymorphisms in angiotensin-converting enzyme gene and severity of renal disease in Henoch-Schoenlein patients. Italian Group of Renal Immunopathology.

BACKGROUND: The influence of angiotensin converting enzyme (ACE) gene polymorphism on the progression of primary IgA nephropathy (pIgAN) is still debated. Even though the allele frequency was reported to be similar to controls, in some studies D/D patients had a faster decline of renal function and need of dialysis. Since Henoch-Schoenlein purpura (HSP) nephritis is considered a systemic vasculitis with renal lesions indistinguishable from pIgAN, we investigated the effect of the ACE polymorphism on presentation and progression of HSP IgAN. METHODS: We examined the insertion (I) and deletion (D) polymorphism in intron 16 of ACE gene by PCR amplification of genomic DNA of 82 patients (37 children), with biopsy-proven IgAN associated with HSP enrolled in a collaborative study. RESULTS: No significant association with clinical presentation at onset or with final outcome was found (functional impairment at outcome in 31.8%, D/D, 27.4%, I/D and 44% I/I, heavy proteinuria in 36.3% D/D, 21.6% I/D, and 11.1% I/I). Patients homozygous for the D allele had a greater number of extrarenal relapses (P=0.0028). No association was found between the ACE genotype and the presence of hypertension at onset and at the end of the follow-up. No difference was found between adults and children. CONCLUSIONS: In this cohort of HSP IgAN, no ACE I/D polymorphisms were found to be associated with progressive deterioration of renal function. Different genes possibly involved in vasculitis might more strictly modulate expression and evolution of HSP IgAN.

Adolescent↗
PubMed1997

Long-term treatment of systemic lupus erythematosus with cyclosporin A.

OBJECTIVE: To evaluate the efficacy of long-term treatment with cyclosporin A (CSA) in systemic lupus erythematosus (SLE). METHODS: Thirty patients with SLE whose condition was either poorly responsive or unresponsive to treatment with steroids and/or cytotoxic drugs were enrolled in a prospective, nonrandomized study of CSA. Patients with hypertension or hypercreatinemia were excluded. Disease activity was evaluated according to the systemic lupus activity measure. Assessments were made prior to study entry and after 6, 12, 18, and 24 months. RESULTS: Twenty-seven patients completed at least 24 months of treatment with CSA. The mean disease activity score significantly decreased after 6 months of therapy (P < 0.01); this result was maintained throughout the study. A conspicuous steroid-sparing effect was observed following administration of CSA (P < 0.01). Side effects included hypertrichosis (63% of patients), paresthesias (23%), gastrointestinal symptoms (20%), gingival hyperplasia (17%), hypertension (10%), tremors (7%), and nephrotoxicity (13%). No significant changes in serum creatinine levels were observed. CONCLUSION: CSA represents a helpful second-choice treatment for patients with active SLE. Administration of CSA necessitates expert and careful followup of patients.

Adolescent↗
PubMed1997

Systemic lupus erythematosus and multiple myeloma: a rare association.

OBJECTIVE: The association of systemic lupus erythematosus (SLE) and multiple myeloma (MM) is an uncommon event. We report the relapse of SLE in a patient with a previous history of MM, treated with chemotherapy and, subsequently, with alpha-2b interferon (alpha-2b IFN) as a maintenance therapy. The case is discussed in light of past relevant literature. METHODS: The history and clinical, laboratory and radiographic findings of the patient, as well as the subsequent therapeutic approach are discussed. In our review of the literature, journal articles are identified by Medline search. RESULTS: We describe the case of a woman who developed a multiple myeloma 14 years after a diagnosis of SLE. A careful literature review confirms that the association of these two diseases has been reported only in a few cases. When the plasma cell neoplasia occurred, SLE had been quiescent for several years; the patient was treated with prednisone-melphalan and, subsequently, with alpha-2b IFN as a maintenance therapy. On admission to our department, SLE was in a relapse phase, probably because of IFN treatment. The disease was poorly responsive to steroid therapy and required the use of cytotoxic drugs. CONCLUSIONS: The coexistence of SLE and MM is very rare and the possible pathogenetic mechanisms underlying this association remain unclear. The use of interferon in a patient with an autoimmune disease always invites caution.

Antineoplastic Agents↗
PubMed1997

Expression of lactoferrin on human granulocytes: analysis with polyclonal and monoclonal antibodies.

Lactoferrin (LF), an iron-binding protein present in specific granules of neutrophils, is expressed on membrane after granulocyte activation. It may represent a target for anti-neutrophil cytoplasmic antibodies (ANCA) in patients affected by some immunomediated diseases. We recently produced two MoAbs, AGM 2.29 and AGM 10.14, that recognize two spatially distant epitopes of human LF. In this study we perform a cytometric analysis in order to evaluate the expression of LF on the surface of granulocytes obtained from freshly drawn blood or after purification, in both the presence and absence of stimuli. Our results demonstrate that LF is not constitutively expressed on membrane of circulating neutrophils. After priming with phorbol myristate acetate (PMA) or tumour necrosis factor-alpha (TNF-alpha), an increased mean fluorescence intensity (MFI) was obtained on neutrophils stained with polyclonal anti-LF antibodies and with AGM 2.29. The kinetics of LF expression during activation demonstrated a progressive increase in MFI within 45 min. No increase in MFI was documented when primed granulocytes were stained with MoAb AGM 10.14, thus indicating that the epitope recognized by AGM 10.14 is not exposed at the cell surface. Following membrane permeabilization, performed in order to analyse the binding of anti-LF MoAbs to cytoplasmic LF, a marked increase in MFI was obtained by staining granulocytes with both anti-LF MoAbs. Indirect immunofluorescence (IIF) analysis confirmed that AGM 2.29 and AGM 10.14 reacted with human granulocytes, showing a cytoplasmic pattern on formalin-acetone-fixed neutrophils and a perinuclear one on ethanol-fixed cells.

Animals↗
PubMed1997

Immunogenetics of Henoch-Schoenlein disease.

In order to investigate the genetic basis of susceptibility to Henoch-Schoenlein purpura (HS), blood samples of 152 patients, 105 of whom had renal disease, were collected in a two-step study. The evaluation of DRB, DQB and DQA polymorphism was done by analysis of the restriction polymorphisms produced by TaqI enzyme. DRB1*07 was less frequent in patients than in the control group (gene frequency 0.09 and 0.18, respectively; P = 0.0023), whereas 64% of the patients were positive for DRB1*01 and/or DRB1*11 compared with 48% of the control group (P = 0.0069). Polymerase chain reaction-sequence-specific oligonucleotide (PCR-SSO) typing of DRB1*01- and DRB1*11-positive individuals did not show any deviation of frequencies of DRB1*01 subtypes between patients and controls, whereas among DRB1*11 subtypes DRB1*1104 was significantly increased in the patients (Pc = 0.033). The comparison between patients with renal disease and those without renal disease showed no significant differences in the frequency of the single DRB, DQB and DQA alleles. The study of restriction polymorphisms in the switch region of the constant genes alpha 1, alpha 2 and mu of the heavy chains of immunoglobulins, using the enzyme Sacl and a specific probe, did not show any difference between 44 patients and 54 controls. This study demonstrates that susceptibility to HS also has a genetic origin: on one hand, the presence of DRB1*01 or DRB1*11 makes disease onset easier; on the other hand, DRB1*07 could induce some resistance to the disease. It is suggested that, as well as for other diseases caused by an impaired immune response, single amino acids in a key position in the HLA-DRB molecule make it more or less easy to recognize some antigenic peptide, towards which an immune response leading to disease is triggered.

Adolescent↗
PubMed1997

Human CD4+ T-cell response to hepatitis delta virus: identification of multiple epitopes and characterization of T-helper cytokine profiles.

The T-cell-mediated immune response plays a crucial role in defense against hepatotropic viruses as well as in the pathogenesis of viral chronic hepatitides. However, very little is known about the role of specific T cells during hepatitis delta virus (HDV) infection in humans. In this study, the T-cell response to HDV in chronic hepatitis B virus (HBV) carriers with HDV superinfection was investigated at different levels. Analysis of peripheral blood mononuclear cell (PBMC) proliferation in response to a recombinant form of large hepatitis delta antigen (HDAg) revealed that 8 of 30 patients studied (27%) specifically responded to HDAg. By employing synthetic peptides spanning the entire HDAg sequence, we found that T-cell recognition was directed against different antigenic determinants, with patient-to-patient variation in the pattern of response to peptides. Interestingly, all responders had signs of inactive HDV-induced disease, while none of the patients with active disease and none of the control subjects showed any significant proliferation. More accurate information about the specific T-cell response was obtained at the clonal level. A panel of HDAg-specific CD4+ T-cell clones from three HDV-infected individuals and fine-specificity analysis revealed that the clones tested individually recognized four epitopes corresponding to amino acids (aa) 26 to 41, 50 to 65, 66 to 81, or 106 to 121 of HDAg sequence. The study of human leukocyte antigen (HLA) restriction revealed that peptides 50 to 65 and 106 to 121 were presented to specific T cells in association with multiple class II molecules. In addition, peptide 26 to 41 was efficiently generated after processing of HDAg through the endogenous processing pathway. Cytokine secretion analysis showed that all the CD4+ T-cell clones assayed were able to produce high levels of gamma interferon (IFN-gamma), belonging either to T helper-1 (Th1) or Th0 subsets and that some of them were cytotoxic in a specific assay. This study provides the first evidence that detection of a specific T-cell response to HDAg in the peripheral blood of individuals with hepatitis delta is related to the decrease of HDV-induced disease activity. The HDAg epitopes identified here and particularly those recognized by CD4+ T cells in association with multiple major histocompatibility complex class II molecules may be potentially exploited for the preparation of a vaccine for prophylaxis and therapy of HDV infection.

CD4-Positive T-Lymphocytes↗
PubMed1997

Hashimoto's thyroiditis associated with urticaria and angio-oedema: disappearance of cutaneous and mucosal manifestations after thyroidectomy.

A 60 year old woman affected by Hashimoto's thyroiditis presented with a history of recurring episodes of urticaria and angio-oedema. Clinical and laboratory evaluation of the patient excluded allergy to external agents, hereditary angio-oedema, and occult infections. A pathogenic relation between Hashimoto's thyroiditis and chronic urticaria/angio-oedema was suspected. However, treatment with L-thyroxine had no influence on the frequency and severity of the cutaneous and mucosal manifestations, which occurred almost daily and required repeated administration of steroids. The patient therefore underwent total thyroidectomy. Cytometric analysis of intrathyroidal lymphocyte subsets showed unusual abnormalities. Urticaria and angio-oedema completely remitted after surgery; 18 months postoperatively the patient was still asymptomatic.

Angioedema↗
PubMed1997

Bone marrow transplantation from unrelated volunteer donors. An overview.

Marrow transplantation from a phenotypically identical unrelated donor has become a feasible and curative form of treatment for patients with several malignant and nonmalignant disorders who lack an HLA-matched sibling donor. Given the rapid growth of registries of HLA-typed volunteers-including nearly 3,000,000 people-it is now possible to identify a suitable unrelated marrow donor for up to 50% of patients. In this review the recent acquisitions regarding the structure of HLA complex, the new molecular typing technologies and clinical results obtained with unrelated marrow transplants, will be considered.

Bone Marrow Transplantation↗
PubMed1997

[Indirect diagnosis of aortic coarctation by Doppler color echography. Velocimetric and spectral aspects in one of our cases].

OBJECTIVE: Description of a case report. PATIENTS: The case of a 55-years-old man with a previous history of hypertension, treated for several years with many antihypertensive drugs without improvement is described. RESULTS: The patient was affected with a unknown coarctation of the aorta. This disease, in fact, is an important cause of secondary hypertension. Adult patients, if asymptomatic, are most often diagnosed because of hypertension or murmur on a routine examination. This congenital disease can be demonstrated on suprasternal notch two-dimensional echocardiographic views along with increased Doppler flow velocity across the coarctation site. TC scan and aortography confirm the degree and nature of the aortic narrowing. CONCLUSIONS: In the case reported color Doppler ultrasonography demonstrated two peculiar aspects of the coarctation of the aorta: 1) detection of a stenotic flow in the abdominal aorta, abdominal and lower extremities arteries; 2) marked renal vasodilatation secondary to compensatory mechanisms that intervene in the renal flow reduction; this finding is detectable in the presence of bilateral stenosis of renal arteries as well as in the hypertensive forms of coarctation of the aorta.

Antihypertensive Agents↗
PubMed1996

Physical and functional independency of p70 and p58 natural killer (NK) cell receptors for HLA class I: their role in the definition of different groups of alloreactive NK cell clones.

Natural killer (NK) cells express clonally distributed receptors for different groups of HLA class I alleles. The Z27 monoclonal antibody described in this study recognizes a p70 receptor specific for HLA-B alleles belonging to the Bw4 supertypic specificity. Single amino acid substitutions in the peptide-binding groove of HLA-B2705 molecules influenced the recognition by some, but not all, p7O/Z27+ clones. This suggests the existence of a limited polymorphism within the p7O family of receptors. The pattern of reactivity of monoclonal antibody Z27 revealed that Bw4-specific receptors may be expressed alone or in combination with different (GL183 and/or EB6) p58 molecules. Analysis of NK clones coexpressing p58 and p7O receptors allowed us to demonstrate that the two molecules represent physically and functionally independent receptors. The expression of p7O molecules either alone or in combination with EB6 molecules provided the molecular basis for understanding the cytolytic pattern of two previously defined groups of "alloreactive" NK cell clones ("group 3" and "group 5").

Amino Acid Sequence↗
PubMed1996

Differential humoral immune response against hepatitis C virus antigenic synthetic peptides in infected patients with and without mixed cryoglobulinaemia.

In this study we have evaluated the prevalence of antibodies against core region peptides (residues 1-28, 21-38 and 51-68), the envelope 1, the non-structural (NS) 4 and 5 proteins of hepatitis C virus (HCV) in sera from 65 chronically HCV-infected patients, 47 with mixed cryoglobulinaemia (MC+) and 18 without (MC-). The major binding sites were located within the core region. Regions 1-28 and 51-68 were recognized by a similar proportion of MC+ and MC- patients, while peptide 21-38 was less frequently detected by samples from MC+ patients (65.5% versus 100%, P = 0.011). The patterns of the reactions showed a minimum of three binding sites: one, located within region 51-68, was shared by both groups; a second determinant was identified at residues 1-21 for MC+ patients and at residues 28-38 for MC- patients; a third, not exactly localized, lay between residues 1 and 38. Recognition of NS5 peptides was not significantly different between MC+ and MC- patients, but while the former mostly reacted either with peptide 1 (residues 2294-2309) (five of 15 sera) or with peptide 2 (residues 2304-2319) (nine of 15 sera), the latter group showed a more scattered reaction. Antibodies to HCV peptides prevalently belonged to IgGl subclass. However, whereas IgGl antibodies against peptide 21-38 and peptide 1 of NS5 were more frequently found in MC- rather than in MC+ patients (100% versus 63.8%, P = 0.003, and 22.2% versus 4.2%, P = 0.025, respectively), IgG3 antibodies against region 1-28 were more frequent in MC+ patients (53.19% versus 16.6%, P = 0.0078). Overall, the data suggest that a differential humoral immune response to HCV antigens occurs in patients with and without cryoglobulinaemia.

Adult↗
PubMed1996

Two spatially distant epitopes of human lactoferrin.

Lactoferrin (LF) is an iron binding protein, which may represent a target for antineutrophil cytoplasmic antibodies (ANCA) in patients affected by rheumatoid arthritis, ulcerative colitis, and primary sclerosing cholangitis. Here we describe the production and characterization of two new monoclonal antibodies (MAbs) against human LF. These MAbs (AGM 10.14, an IgG1, and AGM 2.29, an IgG2b) recognize spatially distant epitopes of LF as assessed by cross-blocking experiments. We also demonstrated by indirect immunofluorescence that both MAbs react with ethanol-fixed neutrophil granulocytes showing a perinuclear staining pattern. AGM 2.29 and AGM 10.14 have been utilized as capture and labeled tracer antibody, respectively, in a double determinant immunoassay (DDIA) to measure soluble LF. The results obtained show that this DDIA allows us to quantify even low concentrations of LF, the maximal range of the assay sensitivity being between 12 and 780 ng/ml. Therefore, AGM 10.14 and AGM 2.29 may represent useful reagents for studying the role of autoantibodies to LF as well as for measuring soluble LF, which is a reliable secretory marker of neutrophil activation.

Animals↗
PubMed1996

Unrelated donor marrow transplantation: initial experience of the Italian bone marrow transplant group (GITMO).

From 1 September 1988 to 30 September 1993, a search for an unrelated donor (URD) was started for 633 Italian patients. Eighty-five of them (13%) were transplanted. Despite the introduction of more strict criteria for the selection of compatible donors, the percentage of patients who reached transplant increased significantly after December 1992. For patients who started a search before and after January 1993, respectively the probability of transplant by 8 and 16 months from search activation was 4 and 10%, compared to 22 and 37% (P = 0.0001). The average intervals between search activation and graft were 15 and 8 months respectively, for the first and second group (P = 0.0001). Data of 75 consecutive transplants performed up to March 1994 were analyzed. Actuarial 2-year survival was 15% for patients grafted before 1992 and 40% for those grafted after January 1992. In this latter period, survival of patients with malignant and non-malignant disorders was 32 and 67%, respectively. In univariate analysis, patients younger than 16 years (P = 0.01), patients grafted after 1992 (P = 0.01) and patients receiving the marrow from a 6-antigen matched donor (P = 0.01) showed a higher survival probability. Multivariate analysis did not show any difference, probably due to the low number of patients and to short follow-up. The adoption of stricter and more accurate HLA-matching criteria and the consequent reduction of deaths related to acute GVHD were the main reasons for the improvement of survival observed in patients grafted after 1992.

Adolescent↗