PubMed Health⌕ Search

Biomedical subjects

V Moulin

Publications and source records attributed to V Moulin.

26 records · Page 2Linked to original sources
PubMed1997

A cholera toxoid-insulin conjugate as an oral vaccine against spontaneous autoimmune diabetes.

Mucosally induced immunological tolerance is an attractive strategy for preventing or treating illnesses resulting from untoward inflammatory immune reactions against self- or non-self-antigens. Oral administration of relevant autoantigens and allergens has been reported to delay or suppress onset of clinical disease in a number of experimental autoimmune and allergic disorders. However, the approach often requires repeated feeding of large amounts of tolerogens over long periods and is only partly effective in animals already systemically sensitized to the ingested antigen such as in animals already harboring autoreactive T cells, and thus presumably also in humans with an autoimmune disease. We have recently shown that oral administration of microgram amounts of antigen coupled to cholera toxin B subunit (CTB), can effectively suppress systemic T cell reactivity in naive as well as in immune animals. We now report that feeding small amounts (2-20 microg) of human insulin conjugated to CTB can effectively suppress beta cell destruction and clinical diabetes in adult nonobese diabetic (NOD) mice. The protective effect could be transferred by T cells from CTB-insulin-treated animals and was associated with reduced lesions of insulitis. Furthermore, adoptive co-transfer experiments involving injection of Thy-1,2 recipients with diabetogenic T cells from syngeneic mice and T cells from congenic Thy-1,1 mice fed with CTB-insulin demonstrated a selective recruitment of Thy-1,1 donor cells in the peripancreatic lymph nodes concomitant with reduced islet cell infiltration. These results suggest that protection against autoimmune diabetes can be achieved by feeding minute amounts of a pancreas islet cell autoantigen linked to CTB and appears to involve the selective migration and retention of protective T cells into lymphoid tissues draining the site of organ injury.

Administration, Oral↗
PubMed1997

Fetal and postnatal sera differentially modulate human dermal fibroblast phenotypic and functional features in vitro.

Fetal wounds heal without scar formation, fibrosis, or contracture. Compared with adult wounds, they are characterized by major differences in the extracellular matrix and the absence of myofibroblastic cells. The reasons for these differences are not well known and determination of factors affecting the absence of scarring in the fetus may lead to strategies for controlling adult pathological scarring. In the present study, we have assessed the effects of serum on the behavior of normal human dermal fibroblasts. Using an in vitro approach, we investigated the effects of fetal and adult serum on cell properties such as growth rate, collagen synthesis, gelatinase activities, and differentiation to myofibroblasts using biochemical, morphological, and ultrastructural parameters. We studied the induction of alpha-smooth muscle (alpha-SM) actin in fibroblasts, and its correlation with increased collagen gel contraction by the cells. Our results showed that, compared with FBS (fetal bovine serum), postnatal calf serum (PCS) decreased mitogenic activity and collagenase synthesis but not collagen synthesis. Furthermore, cells cultured with PCS differentiated to myofibroblasts with an increase in cell diameter, number of stress fibers, alpha-SM actin expression, and collagen gel contraction. To characterize the molecules involved in this differentiation process, the amount of transforming growth factor beta (TGFbeta) in FBS and PCS was determined and the effect of neutralizing anti-TGFbeta antibody was evaluated. It was determined that FBS contained more TGFbeta than PCS, but that essentially all the TGFbeta was latent in both sera. However, results obtained with anti-TGFbeta antibody show that active TGFbeta is present when human dermal fibroblasts are cultured with medium containing PCS. These results suggest that, in the presence of PCS but not FBS, the cells either produce active TGFbeta or an enzyme that is able to activate latent serum TGFbeta. Alternatively, sera may contain two different forms of latent TGFbeta, the PCS form being activated by the dermal fibroblast cells. A similar mechanism may be involved, at least in part, in skin wound healing and may underlie the appearance of myofibroblasts in postnatal wounds.

Animals↗
PubMed1996

In vitro models to study wound healing fibroblasts.

Phenotypic and contractile properties of human fibroblasts from dermis and from an experimental wound model were studied in vitro. When cultured in monolayer, dermal fibroblasts had an elongated spindle shape, were small in diameter and grew at a high rate. Wound fibroblasts grew slowly and were large, star shaped and had cytoplasmic stress fibres. Smooth muscle alpha actin was detected in 10 percent of dermal cells, whereas 20-80 per cent of wound fibroblasts contained this protein in their cytoplasm. The contractile property of cells was evaluated using a three-dimensional cell culture model. Our results show that wound fibroblasts contract collagen gels during the first days more strongly than dermal fibroblasts. These results show that, in vitro, wound fibroblasts have greater contractile capacity than dermal cells. The significant proportion of wound fibroblasts containing alpha-smooth muscle actin suggests that alpha-smooth muscle actin ratio may be related to wound contraction.

Cells, Cultured↗
PubMed1996

[Predictive value of a rapid negativity of serum virus C viremia during treatment with interferon alpha in patients with chronic hepatitis C].

Interferon alpha (INF) used for chronic hepatitis C treatment induces a response in less than 25% of patients. The aim of this study was to appreciate the predictive value of the delay of clearance of hepatitis C virus (HCV) viremia after onset therapy and to compare it with other virological markers such as viral load before treatment and viral type. Thirty one patients with chronic hepatitis C, treated with 3 MU Interferon, 3 times a week for 6 months, were followed until 6 months post-treatment. Response was defined according to the normalisation of transaminases levels and loss of HCV viremia. Five patients were long term responder, eleven patients were complete to relapse responder and fifteen patients were non responder. Serum HCV RNA level, HCV type and serial detection of serum HCV RNA were determined and correlated with the long term response to INF. Patients with long term response had lower pre-INF viral load compared to the complete to relapse responder or to the non responder (p < 0.001). A rapid clearance of serum HCV RNA (1 month) is observed for all the long term responder (p < 0.001). The lowest viral load is also observed in these patients (p < 0 05). By contrast, although the number of patient is low, we were not able to observe a relation between the viral type and the response to treatment. In conclusion this data indicate that the delay of clearance of HCV RNA is also a good predictor of response to INF therapy. Furthermore a rapid clearance of HCV RNA in patients with a very weak pre-INF viral load is strongly associated with long term response (positive predictive value: 100%).

Antiviral Agents↗
PubMed1995

Growth factors in skin wound healing.

The healing of skin involves a wide range of cellular, molecular, physiological and biochemical events. During the healing process, cells migrate to wound sites where they proliferate and synthesize extracellular matrix components in order to reconstitute a tissue closely similar to the original one. This activity is regulated by mediators secreted from the wound border cells such as PDGF, EGF, TGF beta and many other cytokines. Their effects on cells has been demonstrated in vivo and in vitro. The aim of this article is to summarize the sequential events that occur during wound healing notably cell migration, proliferation and phenotypic differentiation and to describe the cellular interactions involving growth factors at the molecular level.

Animals↗
PubMed1993

[Characterization of anti-mitochondrial antibodies type 2 (anti-M2): comparison of two techniques, western blotting and indirect immunofluorescence].

About 94% of patients with typical features of primary biliary cirrhosis (PBC) have been shown to be anti-M2 positive. Today the relevance of anti-M2 antibodies as a diagnostic marker of PBC is well established. The usual method of detection is by indirect immunofluorescence with cryostat sections of rat organs. In our laboratory we have developed a second identification technique for these antibodies: Western-blotting. To compare immunofluorescence and immunoblotting results, we selected sera from 252 patients: 142 sera from patients with documented PBC, 50 from patients with another hepatic disease, 10 from patients with haematological lupus and 50 from healthy blood donors. We characterized antimitochondrial antibody M2 by the presence of one or more of five antigenic determinants: 65-70 kDa (a), 52-54 kDa (b), 44 kDa (c), 23-26 kDa (d) and 16-20 kDa (e). This technique is especially useful as a backup method intention for identifying a very slight or atypical fluorescence pattern.

Autoantibodies↗