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Lionel Prin

Publications and source records attributed to Lionel Prin.

13 recordsLinked to original sources
PubMed2006

Changes in self-reactive IgG antibody repertoire after treatment of experimental autoimmune encephalomyelitis with anti-allergic drugs.

We reduced EAE severity by using two anti-allergic drugs. A control group of mice received i.p. injections of PBS as vehicle while a further two groups were treated either with pyrilamine, a histamine receptor 1 antagonist or with CV6209, a platelet activating factor receptor antagonist. Our results showed that the blockade of the responses to both histamine and PAF leads together to a decline in clinical signs of EAE and significant changes in the serum IgG recognition of some healthy brain antigenic targets. We characterized two discriminant antigens: internexin neuronal intermediate filament protein, and malate dehydrogenase 1, which were able to clearly distinguish untreated mice from treated mice. Their role as potent targets in pathogenic and/or neuroprotective processes is discussed.

Animals↗
PubMed2006

Diversified serum IgG response involving non-myelin CNS proteins during experimental autoimmune encephalomyelitis.

We sequentially analyzed the serum IgG response against normal mouse brain during experimental autoimmune encephalomyelitis in SJL/J mice injected with CFA, Bordetella pertussis toxin (BPT) and proteolipid protein 139-151 peptide, compared with mice that received CFA and BPT or were uninjected. Dynamic changes were observed from day 0 to day 28 in the 3 groups. Six highly discriminant antigenic bands (kappa=0.974) were identified. Three non-myelin proteins were characterized (mitochondrial aconitase hydratase 2, phosphoglycerate mutase 1, brain specific pyruvate deshydrogenase). The IgG response against two of them was less frequent in EAE whereas it was associated with multiple sclerosis in our previous work.

Aconitate Hydratase↗
PubMed2006

[Treatment of hypereosinophilia].

Therapeutic management of blood hypereosinophilia depends on its underlying cause. The cause may be clearly established (parasitic infestation) or more hypothetical (systemic disease). Blood eosinophils often return to normal levels after treatment of either the cause or the associated eosinophilic disease. A targeted approach is more difficult when the cause is unknown (unexplained chronic hypereosinophilia). Various conventional treatments (corticosteroids, hydroxyurea, interferon) have been somewhat effective. The identification of new cellular and molecular markers with diagnostic and pathophysiologic significance makes more rational approaches possible.

Alemtuzumab↗
PubMed2005

[Eosinophilia].

Explore the source record for details and available documents.

Eosinophilia↗
PubMed2005

New insights into cell responses involved in experimental autoimmune encephalomyelitis and multiple sclerosis.

Animal models of autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE) are inflammatory demyelinating diseases which comprise a heterogeneous group of disorders that affect the peripheral and central nervous systems. EAE presents close similarities with multiple sclerosis (MS), a chronic inflammatory disease affecting central nervous system (CNS) white matter. Many studies have shown EAE to be a particularly useful animal model for the understanding of both the mechanisms of immune-mediated CNS pathology and the progressive clinical course of multiple sclerosis. Previous data has underlined the importance of CD4+ T cell involvement in mediating the autoimmune processes associated with the destruction of myelin and the role of the T helper 1 (Th1) pattern of cytokine secretion. However, EAE studies have also demonstrated that other cells involved in innate and/or adaptive immune responses may also play a critical role in the early and progressive events of the immune reaction leading to inflammation and CNS damage. In this review, we present such new data and discuss their potent implication for future new therapeutical approaches.

Animals↗
PubMed2005

Comparative evaluation of two applications for delivering a multimedia medical course in the French-speaking Virtual Medical University (UMVF).

This paper describes a comparative evaluation of two applications delivering a multimedia course: a conventional web server (WS) and an integrated e-learning platform in the form of a virtual campus (VC). We used a qualitative method for comparing their acceptance of the on-line course provided by the two different interfaces. The two groups were globally satisfied. However, a decrease in satisfaction was noted at the end of the experimentation in the VC group. This may be explained by a more complex graphic user interface of the VC and some constraints which do not exist with the WS. Students from both groups also had limitations about the multimedia environment.

Consumer Behavior↗
PubMed2004

Distortion of the self-reactive IgG antibody repertoire in multiple sclerosis as a new diagnostic tool.

To date, none of the myelin-associated Ag targets definitively discriminates between the immune response observed in multiple sclerosis (MS) patients and healthy subjects. However, it has been shown recently that analysis of global immune Ab profiles such as natural autoantibody reactivities can help to distinguish between normal individuals and patients suffering from various immune diseases. The aim of our study was to compare the global IgG immune response against brain self-Ags in sera from 82 MS patients and 27 healthy subjects. The analysis of the immune profiles was performed by Western blotting, and data were subjected to linear discriminant analysis. Particular patterns of IgG reactivity were found in healthy subjects, Sjögren patients, and MS patients. Moreover, this approach separated the three clinical forms of MS with a high concordance rate with the clinical data (kappa value, 77.8%). Our study suggests, for the first time, that serum IgG Ab repertoires are able to distinguish MS patients. In addition, our data suggest that patterns of IgG reactivity could model the pathological processes underlying the various forms of MS. Further characterization of such discriminant Ags could provide useful information regarding their potent role in pathogenesis or regulatory processes in MS.

Adult↗
PubMed2004

New antigenic candidates in multiple sclerosis: identification by serological proteome analysis.

Myelin antigen targets that are clearly associated with pathogenic events in multiple sclerosis (M.S.) patients remain to be defined. We recently demonstrated that the analysis of global IgG antibody response against human brain antigens using one-dimensional (1-D) immunoblotting, allowed us to discriminate M.S. patients from controls (both healthy subjects and patients with Sjögren's syndrome). Additionally, this approach also differentiated the three clinical forms of M.S. Indeed, 42 brain antigenic bands (26 from healthy brain and 16 from the M.S. brain) showed the discriminant IgG immune responses. The aim of our study was to characterize the 26 discriminant antigenic bands detected in healthy brain. Protein identification was successively performed by 1-D and two-dimensional (2-D) immunoblottings using sera from 18 M.S. patients, followed by mass spectrometry (MS) analysis and a database search. One hundred and two antigenic spots were then detected on 2-D immunoblots, with M.S. sera against healthy brains. Sixty-four spots were successfully matched with 2-D Coomassie brillant blue stained gels, which were further selected for MS analysis and annotated leading to the identification of 14 of the 26 discriminant antigens. Thus, serological proteome analysis may provide a useful tool for the identification of potentially new M.S.-associated antigens, whose relevance to physiopathological events remains to be defined.

Adult↗
PubMed2003

Evidence for glycosylphosphatidylinositol (GPI)-anchored eosinophil-derived neurotoxin (EDN) on human granulocytes.

Eosinophil-derived neurotoxin (EDN) is one of the four basic proteins stored in specific eosinophil granules. Here we demonstrate that EDN can also be detected at the surface of granulocytes. Reduction of EDN membrane expression after phosphatidylinositol-specific phospholipase C treatment suggests that a glycosylphosphatidylinositol (GPI) anchor is involved in the membrane association of EDN. The presence of a GPI anchor was confirmed by a lower expression of membrane EDN on granulocytes from patients with paroxysmal nocturnal hemoglobinuria which present cells lacking GPI anchor proteins. Furthermore, metabolic labeling with GPI anchor components supports biochemical evidence of GPI anchoring of EDN.

Blood Donors↗
PubMed2003

Differential effect of dexamethasone on cell death and STAT5 activation during in vitro eosinopoiesis.

Glucorticoids reduce eosinophilia through a direct effect on eosinophils or indirectly on cells producing cytokines and chemokines. Conflicting data have been previously reported concerning glucocorticoid effects on eosinopoiesis. To elucidate this point, dexamethasone was added during eosinophil differentiation of CD34+ cells. Dexamethasone enhanced proliferation and differentiation through an early effect on immature cells. Dexamethasone inhibited apoptosis during early differentiation, whereas death of mature cells was increased. Signal transducer and activator of transcription 5 (STAT5) is a transcription factor involved in the proliferation, differentiation and survival of haematopoietic cells, which interacts with glucocorticoid receptor. Activation of STAT5 by interleukin-5 was investigated during eosinophil differentiation. Long isoforms of STAT5 were activated during the entire period in the culture as well as in blood eosinophils, while short isoforms were only activated during early differentiation. Short isoforms were less activated in the presence of dexamethasone. This suggests that dexamethasone could act on proliferation, differentiation and apoptosis during eosinophil differentiation through an association of STAT5 with the glucocorticoid receptor.

Antigens, CD34↗
PubMed2003

Comparative assessment of two interfaces for delivering a multimedia medical course in the French-speaking Virtual Medical University (UMVF).

The UMVF aims at helping medical students during their normal curriculum via the facilities provided by Internet based techniques. This paper describes a comparative assessment of two interfaces delivering a multimedia course: a conventional web server (WS) and an integrated e-learning platform in the form of a Virtual Campus (VC). Eleven students were arbitrarily divided into two groups. We used a qualitative method for comparing their acceptance of the on line course provided by the two different interfaces. The two groups were globally satisfied. However, a decrease in satisfaction was noted at the end of the experimentation in the VC group. This may be explained by a more complex Graphical User Interface (GUI) of the VC and some constraints which do not exist with the WS. The current e-learning platforms are probably not optimised for working conditions where presential and virtual activities are mixed. We think that a new type of "light" platforms should be developed for these specific working conditions. Students of the two groups also had limitations about the multimedia environment. They may change their opinion if they get more accustomed with the multimedia environment and if their teachers make a more adequate use of the multimedia techniques.

Academic Medical Centers↗
PubMedDate not supplied

Interleukin-10 promoter polymorphism in multiple sclerosis: association with disease progression.

Interleukin-10 (IL-10) is a potent anti-inflammatory and immunosuppressive cytokine that modulates disease expression in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). In previous studies, two dinucleotide repeat elements (microsatellites G and R) were identified, respectively located about 1.1 and 4.0 kb upstream of the IL-10 gene transcription initiation site. Several of their alleles were found to be associated with the level of IL-10 production. The aim of our study was to determine whether sequence variations in the IL-10 gene were associated with MS susceptibility and progression. To do so, we analyzed the distribution of IL-10.R and IL-10.G alleles and genotype polymorphisms in MS patients and healthy controls. We then correlated our findings with disease severity in MS patients using the progression index (PI). Patients were classified as experiencing mild (PI < 0.5) or severe (PI > 0.5) disease progression. Our results show no association between the IL-10.R microsatellite and MS, regardless of disease severity. However, IL-10.G microsatellite genotyping showed that IL-10.G9/9, G10/13, G11/13 and G13/14 were more frequently found in patients with mild disease progression (p = 0.005). We also found that in patients with severe disease progression, IL-10.G9/10, G9/11, G9/13 and G12/13 were over-represented (p = 0.002). Our study indicates that neither the IL-10.R or the IL-10.G alleles are associated with predisposition to MS. However, several IL-10.G genotypes might emerge as markers of disease progression.

Adolescent↗