Autonomic dysfunction in patients with Ataxia-Telangiectasia.
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Adolescent↗
Biomedical subjects
Massimo Fiorilli
Publications and source records attributed to Massimo Fiorilli.
A lymphotactin-producing monoclonal T-cell lymphoproliferative disorder with extreme lymphocytopenia and progressive leukoencephalopathy.
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Adult↗
Hepatitis C virus drives the unconstrained monoclonal expansion of VH1-69-expressing memory B cells in type II cryoglobulinemia: a model of infection-driven lymphomagenesis.
Chronic hepatitis C virus infection causes B cell lymphoproliferative disorders that include type II mixed cryoglobulinemia and lymphoma. This virus drives the monoclonal expansion and, occasionally, the malignant transformation of B cells producing a polyreactive natural Ab commonly encoded by the V(H)1-69 variable gene. Owing to their property of producing natural Ab, these cells are reminiscent of murine B-1 and marginal zone B cells. We used anti-Id Abs to track the stages of differentiation and clonal expansion of V(H)1-69(+) cells in patients with type II mixed cryoglobulinemia. By immunophenotyping and cell size analysis, we could define three discrete stages of differentiation of V(H)1-69(+) B cells: naive (small, IgM(high)IgD(high)CD38(+)CD27(-)CD21(high)CD95(-)CD5(-)), "early memory" (medium-sized, IgM(high)IgD(low)CD38(-)CD27(+)CD21(low)CD95(+)CD5(+)), and "late memory" (large-sized, IgM(low)IgD(low-neg)CD38(-)CD27(low)CD21(low-neg)CD5(-)CD95(-)). The B cells expanded in cryoglobulinemia patients have a "memory" phenotype; this fact, together with the evidence for intraclonal variation, suggests that antigenic stimulation by hepatitis C virus causes the unconstrained expansion of activated V(H)1-69(+) B cells. In some cases, these cells replace the entire pool of circulating B cells, although the absolute B cell number remains within normal limits. Absolute monoclonal V(H)1-69(+) B lymphocytosis was seen in three patients with cryoglobulinemia and splenic lymphoma; in two of these patients, expanded cells carried trisomy 3q. The data presented here indicate that the hepatitis C virus-driven clonal expansion of memory B cells producing a V(H)1-69(+) natural Ab escapes control mechanisms and subverts B cell homeostasis. Genetic alterations may provide a further growth advantage leading to an overt lymphoproliferative disorder.
Adult↗
Central nervous system involvement in hepatitis C virus cryoglobulinemia vasculitis: a multicenter case-control study using magnetic resonance imaging and neuropsychological tests.
OBJECTIVE: Involvement of the central nervous system (CNS) in patients with hepatitis C virus (HCV) mixed cryoglobulinemia (MC) is rare. The mechanism by which brain lesions are produced is unclear. We investigated these phenomena by clinical evaluation (neuropsychological tests) and cerebral magnetic resonance imaging (MRI) studies in patients with HCV-MC vasculitis. METHODS: This prospective study included 40 patients with MC vasculitis and chronic active HCV infection (HCV RNA+), 11 HCV controls without MC, and 36 healthy controls, matched for sex and age. A battery of 10 standardized neuropsychological tests was administered by one experienced neuropsychiatrist. All patients underwent cerebral MRI investigation. RESULTS: Twenty-four of the 27 (89%) evaluated patients with HCV-MC had a deficiency in one or more of the 10 cognitive domains examined. The most commonly involved domains were those of attention (70%), executive functions (44%), visual construction (37%), and visual spatial functions (33%). The number of impaired cognitive functions was significantly higher in patients with MC vasculitis than in HCV controls (2.18 +/- 1.84 vs 0.87 +/- 3.1; p < 0.05). MRI analysis showed that HCV-MC patients had a higher mean number of total (7.03 +/- 9.9 vs 0.90 +/- 1.81 and 2.03 +/- 3.1; p < 0.05) and periventricular (2.4 +/- 3.0 vs 0.38 +/- 0.5 and 0.8 +/- 1.4; p < 0.05) white matter high intensity signals than HCV controls and healthy controls, respectively. CONCLUSION: The high frequency of impaired cognitive function and the extent of MRI brain abnormalities in patients with HCV-associated mixed cryoglobulinemia vasculitis strongly suggest specific inflammatory involvement of the CNS.
Adult↗
Cl- regulates cryoglobulin structure: a new hypothesis for the physiopathological mechanism of temperature non-dependent cryoprecipitation.
Cryoglobulins are pathological cold-precipitable immunoglobulins associated with a number of infectious, autoimmune and neoplastic disorders. Patients, when exposed to low temperatures, show symptoms related to intravascular precipitation of such immunoglobulins. The formation of cryoaggregates induced by exposure to cold temperature is the key pathogenetic mechanism. The subsequent intravascular precipitation can account for some clinical signs of peripheral vasculitis, but fails to explain the precipitation of cryoglobulins in regions where no significant temperature changes take place. We studied, in vitro, the activity of different ions on temperature-dependent aggregation of cryoglobulins and found that the concentration of Cl- present in solution is the most important variable that controls the size and the rate of formation of aggregates, both at low temperature and at 37 degrees C. We suggest that chloride anion could be the most important factor involved in the pathogenesis of events in visceral regions, such as in the kidneys, where no temperature changes occur but where the local Cl- concentration changes to maintain blood electrolytic homeostasis and acid-basic equilibrium. Moreover, identification of a specific structural domain responsible for Cl- binding may provide new targets for drugs selectively designed to interfere with cryoglobulin aggregation.
Anions↗
Human peripheral B cells: a different cytometric point of view.
BACKGROUND: Human peripheral B lymphocytes, analyzed by current flow cytometers, frequently show complex patterns of morphological and fluorescence signals. However, fluorescence intensity values are commonly reported without any correlation to the cell surface area. We propose a different approach, based on the evaluation of the ratio of phenotype fluorescence intensity to forward scatter intensity, to determine the apparent fluorescence density of surface molecules. METHODS: Starting from list mode acquired data, and after logical gating of live B cells, the analytical procedure suggests a serial scanning of the FSC versus SSC plot to obtain apparent fluorescence density of progressively larger cells. RESULTS: This method, applied to normal human peripheral B lymphocytes, was able to detect the presence of steady and modulated (with respect to cell size) fluorescence densities for a variety of surface molecules. B cells from patients with B cell disorders displayed interesting alterations of the phenotype density values and distributions. CONCLUSIONS: Our preliminary data show that, in human B cell cytometry, the apparent fluorescence density based method allows one to recognize variations in fluorescence intensities solely due to cell size differences and to disclose patterns of expression not detectable by the conventional intensity based approach.
Antigens, Surface↗
Analysis of the dynamics of cryoaggregation by light-scattering spectrometry.
Cryoglobulins are proteins that precipitate at temperatures below 37 degrees C. Cold-induced precipitation of proteins may occur in vivo secondary to several important diseases, and lead to pathological manifestations involving different organs. Cryoprecipitation may be observed in vitro by exposing serum samples, supposed to contain cryoglobulins, to low temperatures, but this needs several days to occur. Protein-protein interactions leading to cryoprecipitation are still poorly understood and the knowledge of the underlying mechanism may be relevant to the understanding of the onset of pathological manifestations. Using light-scattering spectrometry, we studied cryoprecipitation occurring in vitro at different temperatures and cryoglobulin concentrations. We describe the kinetics of the cold-induced precipitation of mixed cryoglobulins, measured as increase in turbidity. The plots obtained demonstrate that the cryoprecipitation did not occur as a single-step reaction, but consisted of four distinct phases where both temperature and cryoglobulin concentration affected the immune complexes formation. Light scatter spectrometry may provide a simple, sensitive and rapid method for the detection of cryoglobulins.
Chemistry, Clinical↗
HCV-associated lymphomas.
Epidemiologic and molecular observations have recently suggested that hepatitis C virus (HCV) may be the causative agent of some B-cell non-Hodgkin lymphomas (B-NHL). Epidemiologic data suggest that in Italy about 5% of B-NHL are caused by HCV. Molecular data indicate a close relationship between HCV-associated B-NHL and type II mixed cryoglobulinemia. The latter disorder appears to reflect the benign monoclonal proliferation of B cells expressing a specific cross-reactive idiotype, known as WA, that may recognize an antigen of HCV, perhaps the E2 protein. Genetic abnormalities occurring during this phase of antigen-induced clonal expansion may drive the neoplastic transformation into low- or high-grade lymphoma. The recent demonstration that splenic B cell lymphomas associated with HCV-infection may regress after successful antiviral therapy confirms a role for this virus in B-cell lymphomagenesis.
Antineoplastic Agents↗
Skewed T-cell receptor repertoire, decreased thymic output, and predominance of terminally differentiated T cells in ataxia telangiectasia.
Ataxia telangiectasia (A-T), a genetic disorder caused by the homozygous mutation of the ATM gene, frequently associates with variable degrees of cellular and humoral immunodeficiency. However, the immune defects occurring in patients with A-T are still poorly characterized. Here we show that the T-cell receptor (TCR) variable beta (BV)-chain repertoire of 9 A-T patients was restricted by diffuse expansions of some variable genes prevalently occurring within the CD4 subset and clustering to certain TCRBV genes (eg, 5.1, 11, 14, and 23). In addition, the study of the third complementarity-determining region (CDR3) showed, in all patients, significantly altered profiles in most BV genes examined suggesting diffuse oligoclonal expansions. The sequencing of TCR CDR3 regions revealed completely normal V(D)J coding joints and confirmed a reduced diversity of the antigen-receptor repertoire. The B-cell repertoire was similarly restricted and skewed by diffuse oligoclonal expansions with normal V(D)J joints. Thymic output, evaluated by measuring TCR rearrangement excision circles, was extremely low. The majority of peripheral T cells had the phenotype and the function of effector memory cells, indicating that in vivo they are able to respond normally by terminal differentiation to antigenic stimulation. These results indicate that ATM mutation limits the generation of a wide repertoire of normally functioning T and B cells.
Adolescent↗
Regression of lymphoproliferative disorder after treatment for hepatitis C virus infection in a patient with partial trisomy 3, Bcl-2 overexpression, and type II cryoglobulinemia.
A patient with type II cryoglobulinemic vasculitis and hepatitis C virus (HCV) infection presented with a leukemiclike proliferation of B cells bearing marginal zone B-cell phenotypic markers. A partial trisomy 3 (bands 3q11-29) and overexpression of Bcl-2 without t(14;18) translocation was detected in the monoclonal B cells that were classic rheumatoid factor-producing B cells bearing the WA cross-idiotype. Treatment with interferon-alpha produced a complete clinical remission and synchronous marked decreases in viremia and monoclonal B-cell prevalence. This is the first report of partial trisomy 3 and Bcl-2 overexpression in type II cryoglobulinemic vasculitis associated with HCV infection. Further studies of HCV-infected patients with and without type II cryoglobulinemia are required to determine the prevalence and possible physiologic and/or pathophysiologic significance of these findings.
Chromosomes, Human, Pair 3↗
Influence of age and autoimmunity on liver disease in HCV-associated type II mixed cryoglobulinemia.
It has been suggested that hepatitis C virus (HCV) infected patients with type II mixed cryoglobulinemia have less extensive liver damage than patients without cryoglobulinemia. We retrospectively evaluated 35 patients with type II mixed cryoglobulinemia associated with HCV infection, seeking for factors associated with normal alanine aminotransferase (ALT) values. The presence of anti-GOR and of other autoantibodies, including the recently described anti-LAG-3.1, was specifically investigated. Fifty-four percent of patients had anti-GOR, 46% anti-LAG-3.1, 40% anti-smooth muscle, 17% anti-nuclear, and 11% anti-liver-kidney microsome 1 antibodies. Anti-GOR was significantly (p = 0.037) associated with anti-LAG-3.1 but not with other autoantibodies. Persistently abnormal ALT levels were observed in 54% of patients. By univariate analyses, abnormal ALT was significantly associated with anti-GOR positivity (p = 0.018) and younger age (p = 0.03). Multivariate regression analysis confirmed that these variables were independently associated with abnormal ALT. Our data suggest that the presence of autoimmune manifestations as well as unidentified age-related host factor(s) may protect from liver injury in HCV-associated cryoglobulinemia.
Adult↗