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V Perfetti

Publications and source records attributed to V Perfetti.

34 records · Page 2Linked to original sources

Reversal of nephrotic syndrome due to reactive amyloidosis (AA-type) after excision of localized Castleman's disease.

The patient (TAL), a chronic asymptomatic HBV carrier with HBsAg-anti-HBsAg circulating immune complexes, was admitted to our hospital because of a nephrotic syndrome due to renal amyloidosis. There was no family history of hereditary amyloidosis. Recurrent arthralgias, asthenia, and weight loss were the prominent clinical features. Laboratory test results showing that severe chronic inflammatory activity had been present for 6 years. Interleukin-6 (IL-6) serum concentration was 10 times normal and C-reactive protein was 1.9 mg/ml. A complex immunological picture was also present (immune complex formation, exuberant B-cell reactivity, and decrease in the number of CD4 T cells). A localized form of Castleman's disease (CD) (plasma-cell type) was diagnosed by surgical excision of a giant axillary lymph node. AA amyloid was present in the blood vessels. Within 60 days after excision of the mass, the systemic symptoms subsided, laboratory signs of inflammatory activity disappeared and IL-6 serum concentration returned to normal, thus establishing a causal relationship between the localized Castleman's disease, elevated IL-6 concentration and the chronic inflammation responsible for AA amyloidosis. At 10 months of follow-up, the nephrotic syndrome has reversed, kidney function has slowly ameliorated, and the patient has gained 12 kg. Abdominal fat aspirates drawn to search for amyloid, positive before surgery, were subsequently negative. The latter finding, and the remission of the nephrotic syndrome, provided strong evidence for regression of the amyloid deposits. However, the HBsAg-anti-HBsAg immune complexes and depression of T-helper cell activity persist. This immunological derangement is therefore not a consequence of CD. Chronic stimulation of the immune system due to the patient's inability to eliminate HBV, in the contest of perturbed immunity, may have favored the genesis of the lymphadenopathy.

Adult↗

AL amyloidosis. Characterization of amyloidogenic cells by anti-idiotypic monoclonal antibodies.

BACKGROUND: AL amyloidosis is characterized by systemic tissue deposition of monoclonal Ig light chains synthesized by a bone marrow plasma cell (PC) clone whose biologic characteristics remain undetermined. EXPERIMENTAL DESIGN: Anti-idiotypic (anti-Id) monoclonal antibodies (MoAbs) were used as specific probes to identify and study amyloidogenic cells in two patients by means of immunofluorescence methods. These MoAbs recognized populations of bone marrow pre-PC, PC, and peripheral blood lymphocytes. To test whether the circulating Id+ lymphocytes were capable of PC differentiation, peripheral blood lymphocytes were incubated with the differentiation-inducing agents, interleukin-3 and interleukin-6 in liquid culture. Preincubation with the anti-Id MoAb and complement was used to inhibit formation of Id+PC in vitro. RESULTS: The anti-Id MoAb identified three types of cells in the bone marrow with cytoplasmic Ig having the same isotype as the monoclonal component: a) lymphoid cells, that were slightly larger than common peripheral blood lymphocytes (47% CD45RA+, 28% CD45R0+, 97% CD38-, 100% CD10-, 100% mu-chain-); b) lymphoplasmacytoid cells with more abundant cytoplasm and Id+ Ig (CD45RA-, CD45RO-, CD10-, 53% CD38+); 3) mature PC that were very similar to normal PC in morphology and antigenic profile (CD38+, PCA1+, CD56-). A different picture was seen when anti-Id MoAb were used to detect peripheral blood Id+ elements: analysis revealed a population of mature resting surface Ig+ B lymphocytes. Circulating Id+ lymphocytes differentiated in vitro to PC and lymphoplasmacytoid cells that were very similar to those present in the bone marrow. A significant reduction in the number of Id+ PC was obtained after incubation with the anti-Id MoAb and complement. CONCLUSIONS: This study shows that the amyloidogenic cell clone is constituted by at least the following cell populations: a fraction of bone marrow cells (lymphoid, lymphoplasmacytoid cells and PC) and a subset of peripheral blood post-switched B lymphocytes. The results suggest a relationship among these cells, indicating that circulating Id+ lymphocytes may be the possible precursors of the more differentiated bone marrow population.

Amyloidosis↗

Acute phase proteins and prognosis in multiple myeloma.

Serum IL-6 levels have been shown to correlate with disease severity and prognosis in patients with plasma cell dyscrasias. Among its pleiotropic actions, IL-6 is also the major regulator of the acute phase response in humans. The possible impact on survival of the major serum acute phase proteins (s.APP) [C-reactive protein (s.CRP), alpha-1-antitrypsin (s.AAT), haptoglobin, acid alpha-1-glycoprotein and alpha-2-macroglobulin (used as control)] was assessed on a population of 103 consecutive, previously untreated myeloma patients. Univariate analysis showed that among the acute phase proteins only s.AAT (P = 0.015) and s.CRP (P = 0.027) were significantly correlated with survival. The multivariate Cox proportional hazard model applied to s.APP and other common parameters showed that s.beta-2-microglobulin (s.b2M), s.calcium, s.creatinine, BM plasma cell percentage, age and s.AAT correlated significantly with survival. Combining s.b2M and s.AAT allowed stratification of myeloma patients: those with low levels of s.b2M (< or = 3 mg/l) and of s.AAT (< or = 3 g/l) presented an excellent prognosis (median survival exceeding 10 years) while those presenting higher values of the two parameters presented a median survival of 2.5 years (P = 0.002).

Acute-Phase Proteins↗

Application of monoclonal anti-idiotypes in the study of AL amyloidosis: therapeutic implications.

A monoclonal anti-idiotyped antibody (IgG1k MAb 3B11D4) has been raised against the lambda-chain dimers isolated from the urine of a patient (DEP) with AL amyloidosis. This antibody binds a conformational idiotope present on the monoclonal DEP IgA, but does not recognize the reduced and alkylated lambda-chain monomers, nor the 15- to 17-kDa light chain fragments obtained from the amyloid fibrils, which have the same N-terminal sequence as the urinary light chains. The nonreactivity of this MAb with amyloid fibrils was confirmed by immunohistochemical examination of cryostatic sections of an amyloidoma surgically removed from the patient's subcutaneous tissue. Our data demonstrate that the deletion of about 70 amino acid residues of the C-terminus of the lambda chain prevents the formation of the self-limiting dimer and may facilitate the deposition of fragments into amyloid fibrils. With regard to the amyloidogenic clone, MAb 3B11D4 recognizes the plasma cell clone in bone marrow and 9% of circulating B lymphocytes. Panning and cytotoxicity experiments demonstrate that this antibody has the capability of selectively eliminating the idiotype-positive cells from peripheral blood. Antibodies with these properties could find application in a new therapeutic strategy which provides high-dose chemotherapy, total body irradiation, and rescue with circulating stem cells. These antibodies could be used in two distinct phases: first, in the purging of the stem cells to be infused from the amyloidogenic clone and, secondly, in an attempt to eliminate residual disease by intravenous infusion.

Amyloid↗

Use of an anti-idiotypic monoclonal antibody in studying amyloidogenic light chains in cells, urine and fibrils: pathophysiology and clinical implications.

A monoclonal anti-idiotype antibody (IgG1k MoAb 3B11D4) raised against the amyloidogenic DEP lambda chain dimer binds a conformational idiotope also present on the monoclonal DEP IgA immunoglobulin. MoAb 3B11D4 does not recognize the reduced and alkylated lambda chain monomers, nor the 15-17-kDa fibrillar light chain fragments which have the same N-terminal sequence of the urinary light chains. The lack of about 70 amino acid residues of the C terminal of the protein prevents the formation of the self-limiting dimer and may facilitate the deposition of the fragments into amyloid fibrils. MoAb 3B11D4 recognizes the plasma cell clone in bone marrow and 9% of circulating B lymphocytes. Panning experiments demonstrate that this antibody has the capability to selectively eliminate the idiotype positive cells from peripheral blood. Antibodies with these characteristics could become a useful tool for better understanding the pathogenesis of the disease and for new therapeutic options.

Amino Acid Sequence↗

Expression of housekeeping genes in Hodgkin's disease lymph nodes.

Housekeeping genes, particularly actin, tubulin, and the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH), are widely used to estimate the amount and integrity of RNA in Northern blotting. In this work, the most reliable housekeeping gene for gene expression analysis of Hodgkin's disease (HD) lymph nodes was determined by comparing the conventional housekeeping genes, beta-actin, beta-tubulin, GAPDH, and the mouse gene LLRep3, that had been used previously in gene expression studies. It was found that the amounts of mRNA in these genes are very heterogeneous in HD lymph nodes. In contrast, their expression was relatively constant in tonsils undergoing a chronic inflammatory process. It is concluded that none of the housekeeping genes tested is suitable for the fine quantitative analysis of gene expression in HD lymph nodes.

Actins↗

Relevance of class, molecular weight and isoelectric point in predicting human light chain amyloidogenicity.

The ability to predict the amyloidogenicity of certain light chains may facilitate an earlier diagnosis of AL amyloidosis and, possibly, lead to more effective treatment. Using current methods, available in clinical chemistry laboratories, we assessed the class, the relative molecular mass (Mr) and the isoelectric point of urinary monoclonal light chains from 35 patients with AL amyloidosis (A+) and 51 without amyloidosis (A-). The light chain class (LCC) was lambda in 77% and 45% of A+ and A- patients, respectively. Light chain fragments (LCF) with low Mr (12-18 x 10(3) were detected in the urine of 30/35 A+ patients and in 15/51 A- ones. The mean (SD) isoelectric point (pI) of A+ light chains was 4.8 (1.1) while in A- patients it was 6.2 (1.6). Univariate analysis showed significant differences between the two groups for the three parameters. Discriminant analysis gave a function which allowed a correct allocation of 81% of the cases between the two groups.

Amyloidosis↗

Specificity and variable region cDNA sequence of an isogeneic monoclonal antiidiotype to an anti-alpha(1----6)dextran.

We have characterized a monoclonal isogeneic antiidiotype, IdB5.7, from a BALB/c mouse immunized with the anti-alpha(1----6)dextran C57BL/6 45.21.1. It defined a hapten-inhibitable idiotope expressed on four of the 2 myeloma and 37 hybridoma anti-alpha(1----6)dextrans tested. Sequence comparison of Id+ and Id- anti-alpha(1----6)dextrans suggested that two extra amino acids at VH 100A and 100B and different residues at VH 101 abolish the expression of the idiotope in the Id- anti-alpha(1----6)dextrans. Sequence analysis of the VH of IdB5.7 showed a CDR1 longer than usual and a D segment in CDR3 formed by the fusion of two D minigenes. The IdB5.7 V kappa uses the V kappa 1 germline gene K5.1 with a few substitutions. The D-D fusion in VH CDR3 is a feature which has been reported in several other antiidiotypic antibodies.

Amino Acid Sequence↗

Gene expression of pyrogenic cytokines in Hodgkin's disease lymph nodes.

BACKGROUND: Inflammatory cytokines released by either the neoplastic or reactive cells in Hodgkin's disease (HD) might mediate its peculiar clinical and histopathological features. We investigated by Northern blotting the gene expressions of the pyrogenic and inflammation-associated cytokines IL-1 alpha, IL-1 beta, TNF-alpha, TNF-beta (lymphotoxin) and IL-6 in 14 HD lymph nodes and studied their relation to systemic symptoms (B symptoms). METHODS: Two ug of poly(A)+RNA from 14 HD lymph nodes (8 from symptomatic and 6 from asymptomatic patients, of different histological type and disease stage) were subjected to agarose electrophoresis, Northern blotted and hybridized to the various cytokine cDNA probes. RESULTS: The inflammatory cytokines were expressed very heterogenously in HD, even in lymph nodes with the same histological type and with similar stromal inflammatory reactions. IL-1 beta was increased about 2 to 10 times in 5 of 8 lymph nodes from patients with B symptoms, whereas the other cytokines were heterogenously expressed in both symptomatic and asymptomatic patients. Statistical analysis on densitometric values demonstrated that the difference in IL-1 beta expression between symptomatic and asymptomatic patients was significant (p less than 0.02). CONCLUSIONS: These results support the hypothesis of increased IL-1 levels in tumoral lymph nodes from symptomatic HD patients.

Cytokines↗

Diagnostic approach to and follow-up of difficult cases of AL amyloidosis.

BACKGROUND: Routine electrophoretic analysis fails to detect a monoclonal component (MC) in a considerable portion of AL amyloidosis patients. We investigated whether the combination of immunofixation (IF) on agarose gel electrophoresis and bone marrow plasma cell (BMPC) light chain kappa/lambda ratio analysis could contribute to diagnosis in these cases. The possible use of the BMPC kappa/lambda ratio in monitoring the clone was also investigated. METHODS: We performed BMPC kappa/lambda ratio analysis and IF of serum and urine in 16 selected patients with no detectable MC at routine analysis, despite clinical features suggestive of primary amyloidosis. An anti-idiotypic monoclonal antibody specific for the amyloidogenic immunoglobulin and the BMPC kappa/lambda ratio were used to monitor the clone in a patient who underwent autologous peripheral blood stem cell transplantation. RESULTS: Abnormal kappa/lambda ratios were found in 14 (sensitivity 87.5%), and a MC in 12 (sensitivity 75%). Combination of the two analyses confirmed diagnosis in all cases. In one patient changes in the size of the clone, monitored on serial bone marrow aspirates by an anti-idiotypic antibody, paralleled variations of the kappa/lambda ratio. CONCLUSIONS: This study demonstrates that the combined use of IF and the BMPC kappa/lambda ratio is extremely powerful in AL amyloidosis. In addition, the BMPC kappa/lambda ratio should be considered for monitoring the amyloidogenic clone when serum or urine MC is not quantifiable.

Adult↗

Immunochemical characterization of the cryoglobulins: pathophysiologic implications.

Immunochemical study of the cryoglobulins has produced a classification of three main types which present clinical correlates. With the current standard immunofixation technique the vast majority of cryoglobulins are presently classified as type II. High-resolution immunoelectrophoretic techniques (immunoblotting and two-dimensional polyacrylamide gel electrophoresis) have helped to identify new sub-types whose clinical relevance is as yet undetermined. Nevertheless, these sensitive techniques could contribute to elucidate the various stages in the natural history of HCV-related cryoglobulins, from possible earlier HCV-antigen-driven polyclonal B cell proliferation, to autonomous monoclonal benign, to malignant B cell proliferation.

Cryoglobulins↗