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Biomedical subjects

Giovanni Luigi Mancardi

Publications and source records attributed to Giovanni Luigi Mancardi.

7 recordsLinked to original sources

Human mesenchymal stem cells modulate B-cell functions.

Human mesenchymal stem cells (hMSCs) suppress T-cell and dendritic-cell function and represent a promising strategy for cell therapy of autoimmune diseases. Nevertheless, no information is currently available on the effects of hMSCs on B cells, which may have a large impact on the clinical use of these cells. hMSCs isolated from the bone marrow and B cells purified from the peripheral blood of healthy donors were cocultured with different B-cell tropic stimuli. B-cell proliferation was inhibited by hMSCs through an arrest in the G0/G1 phase of the cell cycle and not through the induction of apoptosis. A major mechanism of B-cell suppression was hMSC production of soluble factors, as indicated by transwell experiments. hMSCs inhibited B-cell differentiation because IgM, IgG, and IgA production was significantly impaired. CXCR4, CXCR5, and CCR7 B-cell expression, as well as chemotaxis to CXCL12, the CXCR4 ligand, and CXCL13, the CXCR5 ligand, were significantly down-regulated by hMSCs, suggesting that these cells affect chemotactic properties of B cells. B-cell costimulatory molecule expression and cytokine production were unaffected by hMSCs. These results further support the potential therapeutic use of hMSCs in immune-mediated disorders, including those in which B cells play a major role.

B-Lymphocytes↗

B-cell differentiation in the CNS of patients with multiple sclerosis.

Clonally expanded populations of Ig variable gene-mutated B cells are found in the central nervous system (CNS) of subjects with multiple sclerosis (MS), suggesting the occurrence of a germinal center-like reaction. Recent studies have demonstrated that the cerebrospinal fluid (CSF) of MS patients is enriched with centroblasts and B cells with a memory phenotype compared to peripheral blood. In the same individuals, antibody-secreting cells (ASC) are detected in the CSF and appear to correlate with CNS inflammation. These B-cell subsets are the output of a germinal center reaction, which is likely to occur in the CNS. Recent findings suggest that the inflamed brain can become a favorable niche for B-cell survival and proliferation and, under some circumstances, sustain the formation of ectopic lymphoid structures. Thus, B cells are likely to expand and mature inside the CNS, giving rise to ASC, which may play an effector role in the pathogenesis of MS.

Antigens, CD↗

Autologous stem cell transplantation as rescue therapy in malignant forms of multiple sclerosis.

Malignant forms of multiple sclerosis (MS) represent a limited group of very aggressive demyelinating diseases, which rapidly progress to severe disability leading often to life-threatening conditions. On these clinical entities, currently available therapies for MS are not very effective. Recently, it has been demonstrated that intense immunosuppression followed by autologous stem cell transplantation (ASCT) can affect the clinical course of individuals with severe MS and completely abrogate the inflammatory activity detected by magnetic resonance imaging (MRI). We report on the treatment with intense immune ablation followed by ASCT of three patients with malignant MS whose clinical course indicated a dramatically poor prognosis. This procedure succeeded in halting the rapidly worsening course of disease. The effect was long lasting, as demonstrated by a sustained efficacy over a two-year period in two subjects and 12 months in the third case. In addition, a striking effect on inflammation-related MRI findings was obtained. These results support a role for intense immunosuppression followed by ASCT as treatment in rapidly evolving malignant MS cases unresponsive to conventional therapies.

Adolescent↗

Recapitulation of B cell differentiation in the central nervous system of patients with multiple sclerosis.

Clonally expanded populations of B cells carrying somatic mutations of Ig variable (V) region genes have been detected in the CNS of subjects with multiple sclerosis (MS), suggesting that a process of B cell affinity maturation with ensuing production of potentially pathogenic autoantibodies may occur inside the CNS. Here, we have characterized the B cell subsets present in the cerebrospinal fluid (CSF) of MS patients and of individuals with other inflammatory neurological disorders by flow cytometry. CD19(+)CD38(high+)CD77(+), Ki67(+), Bcl-2(-) centroblasts, i.e., a B cell subset found exclusively in secondary lymphoid organs, were detected in the CSF but not in paired peripheral blood from both patient groups. CD27(+)IgD(-) memory B cells, i.e., cells with hyper-mutated IgV genes, were significantly increased in the CSF vs. paired peripheral blood and displayed up-regulation of the CD80 and CD86 costimulatory molecules and of CC chemokine receptor (CCR) 1, CCR2, and CCR4 in both patient groups. Lymphotoxin-alpha, CXC ligand (CXCL) 12, and CXCL13, key mediators of lymphoid neogenesis, were present in the CSF from patients with MS and other inflammatory neurological disorders and were expressed in MS brain tissue, with selective localization in the outer layer of the capillary vessel wall. In conclusion, this study suggests that a compartmentalized B cell response occurs within the CNS during an ongoing inflammatory reaction, through a recapitulation of all stages of B cell differentiation observed in secondary lymphoid organs. The presence of lymphotoxin-alpha, CXCL12, and CXCL13 in the CNS may provide favorable microenvironmental conditions for these events.

Antigens, CD↗

Cerebellar ataxia: quantitative assessment and cybernetic interpretation.

To assess neuromotor disorders clinicians often rely on rating scales. Unfortunately, these scales lack the sensitivity and accuracy needed to detect the small changes in motor coordination that reflect the clinical progression of the disease on the basis of which treatment programmes can be adjusted. As a contribution to this topic, the present paper proposes a straightforward kinematic and kinetic analysis of reaching movements of patients with cerebellar ataxia in conjunction with a cybernetic interpretation of the data. The aim of the approach is to capture key deficits in the underlying motor control processes. We suggest that cerebellar ataxia may be characterized by defective feedforward control.

Cerebellar Ataxia↗

Phenotypic and functional analysis of T cells homing into the CSF of subjects with inflammatory diseases of the CNS.

The recruitment of lymphocytes across the blood brain barrier (BBB) is mediated by adhesion molecules and chemokines. The expression of activation markers and of chemokine receptors on T cells homing to the nervous system (NS) may help define their functional state. In the cerebrospinal fluid (CSF) of subjects with inflammatory neurological diseases (IND), including multiple sclerosis, we observed an increased number of T cells coexpressing CXCR3 and CCR5 as well as T cells with a CD45RO+ CCR7+ CD27+ memory phenotype. A subset of CCR7+ T cells coexpressed CXCR3 and CCR5. We also detected an increased number of interferon-gamma-producing T cells in the CSF compared with peripheral blood, mostly but not exclusively in the CD45RO+ CCR7- CD27- compartment. T helper 1 (Th1) clones, established from the CSF of individuals with IND and from a healthy subject, similarly migrated to CXCL10, CXCL12, and CCL5. CXCL10, CXCL12, and CCL19 were increased in the CSF of individuals with neuroinflammation. These findings suggest that CSF is enriched in Th1-polarized memory T cells capable of differentiating into effector cells upon antigen encounter. These cells are recruited into the CSF by inducible chemokines. Thus, CSF represents a transitional station for T cells trafficking to and from the NS.

Adult↗

Assessment of normal-appearing white and gray matter in patients with primary progressive multiple sclerosis: a diffusion-tensor magnetic resonance imaging study.

BACKGROUND: Diffusion-tensor magnetic resonance imaging is sensitive to the more destructive aspects of multiple sclerosis (MS) evolution occurring outside and within T2-visible lesions and, as a consequence, holds promise for providing a more complete picture of primary progressive (PP) MS-related tissue damage than conventional magnetic resonance imaging. OBJECTIVE: To improve our understanding of PPMS by assessing the extent of occult pathological features in the normal-appearing white and gray matter of the brain using diffusion-tensor magnetic resonance imaging. METHODS: Ninety-six patients with PPMS, 47 patients with secondary progressive (SP) MS, and 44 healthy control subjects were studied. T2-hyperintense and T1-hypointense lesion volumes were calculated, and the volume of the whole brain tissue was measured. Diffusion-tensor magnetic resonance imaging scans were postprocessed and analyzed to obtain the mean diffusivity and fractional anisotropy histograms from the brain and from the normal-appearing white and gray matter in isolation. RESULTS: The mean T2-hyperintense and T1-hypointense lesion volumes were lower in patients with PPMS than in patients with SPMS, while the mean absolute brain volumes were similar in the 2 groups. The average lesion diffusivity was significantly higher in patients with SPMS than in patients with PPMS (P<.001). Histogram-derived metrics of the brain tissue and normal-appearing white and gray matter were significantly different between patients with PPMS and healthy subjects (range, P =.004 to <.001). Average diffusivity values were significantly higher in patients with SPMS than in patients with PPMS for all the tissues studied (range, P =.001 to <.001). Fractional anisotropy histogram-derived quantities did not significantly differ between the 2 patient groups (range, P =.94 to.03). CONCLUSION: This study confirms that, in patients with PPMS, normal-appearing white and gray matter are not spared by disease-related pathological processes, although they are affected to a lesser degree than in patients with SPMS.

Adult↗