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N Fabien

Publications and source records attributed to N Fabien.

42 records · Page 3Linked to original sources
PubMed1989

Quantitative analysis of cultured thymic reticulo-epithelial cells labelled by different antibodies: a flow cytometric study.

Quantitative measurements of cultured human and murine thymic, and human thymoma reticuloepithelial cells (REC), immunolabeled by different antibodies (Ab) (TE3, TE4, anti-HTLV p19(p19), lu5, K11 and Aks) and by thymic hormones (thymulin and thymosin alpha 1 (Ta1)) within these cells, were performed using a flow cytometric technique. The anti-keratin polyclonal Ab labeled nearly the whole human or murine population. The p19 monoclonal Ab (MoAb), specific for the subcortical/medullary thymic regions, labelled 37-77% of the human REC. The TE3 MoAb, specific for the cortical region, labelled 54-83% of the REC. These percentages suggest that the cultured thymic REC (TREC) had markers of both regions together and therefore that these markers are not absolutely specific to determine their subcortical/medullary or cortical thymic origin. For the three populations there were more cells containing Ta1 than thymulin. The overlap of the percentage of labelled cells suggests that the same cell could synthesize the two hormones and that these hormones could be localized within the TE3 positive cells.

Animals↗
PubMed1988

Immunolocalization of thymosin alpha 1, thymopoietin and thymulin in mouse thymic epithelial cells at different stages of culture: a light and electron microscopic study.

The secretory evolution of the thymic hormones (thymulin, thymosin alpha 1 and thymopoietin) in cultured thymic reticuloepithelial cells (TREC) was studied by immunocytochemical techniques using monoclonal anti-thymulin or anti-thymosin alpha 1 and polyclonal anti-thymopoietin antibodies (Ab). The culture of TREC was performed with a medium where L-valine was replaced by D-valine, thus ensuring rapid and selective development of these cells. The number of thymulin, thymosin alpha 1 or thymopoietin-containing cells increased progressively from Day 6 to Day 12 of the culture. The localization of the three thymic hormones within the TREC also varied according to the age of the culture. By light microscopy the staining of the three hormones was localized in some cytoplasmic granules at the beginning of the culture and at Day 90, while at Day 12 it was throughout the cytoplasm. In electron microscopy these localizations corresponded respectively to vacuoles of different sizes and to cytosol. All these results show that the synthesis and excretion of thymulin, thymosin alpha 1 and thymopoietin evolve during the development of TREC in culture.

Animals↗
PubMed1988

Immunoreactivity of aqueous extracts of rat and mouse tissue with anti-thymosin alpha 1, anti-bovine thymopoietin and anti-thymulin antibodies. Studies using immunoblotting.

Anti-thymosin alpha 1 monoclonal antibodies recognized, on immunoblots, 1 to 2 bands corresponding to molecules of 34 and 35 Kd when using aqueous extracts of thymus, spleen, kidney, liver, brain, pituitary and adrenal glands from rats or mice. Anti-bovine thymopoietin polyclonal antibodies, in the same conditions, labelled analogous 34, 35 and 35.5 Kd molecules in brain and thymus extracts but also a 40 Kd molecules in thymus and a 90 Kd in brain extracts. Anti-synthetic thymulin monoclonal antibodies recognized irregularly and poorly a 52 Kd molecule from thymus and brain extracts. These results suggest that thymopoietin, thymulin and specially Thymosin alpha 1 are first synthesized in large precursors. Finally, other organs seem capable of synthesizing thymosin alpha 1 and probably thymopoietin, but for thymulin, the results are too irregular to conclude.

Animals↗
PubMed1987

Intracellular localization of thymosin alpha 1 by immunoelectron microscopy using a monoclonal antibody.

Distribution of thymosin alpha 1 in normal mice (OF1) or autoimmune mice (NZB) was investigated using immunocytochemical techniques on sections of GMA- and Epon-embedded mouse thymuses. A monoclonal antibody directed against synthetic thymosin alpha 1 was used. With the immunofluorescence assay, patchy staining of thymosin alpha 1 was found in the cytoplasm of epithelial cells of the subcapsullary and medullary zones of OF1 thymus. In NZB thymus, the fluorescent pattern was less precisely localized. At the electron microscopic level, immunolabeling of Epon-embedded ultra-thin sections revealed ferritin in some vacuoles of epithelial cells. Ferritin labeling in OF1 thymus was found in several small vacuoles of the same cell, but was present in large, dense vacuoles in NZB thymus. These differences might reflect differences in the secretory process of thymic hormone.

Animals↗
PubMedDate not supplied

Hepatitis C virus infection is frequently associated with high titers of anti-thyroid antibodies.

Objective: To assess the implication of hepatitis C virus (HCV) infection in the development of autoimmune thyroid response, thyroid autoantibodies were studied in serum of HCV positive patients. Methods: Anti-microsomal, anti-thyroperoxidase (anti-TPO) and anti-thyroglobulin antibodies were evaluated in the sera of 100 patients with chronic hepatitis C (53 women and 47 men; mean age = 55&#x00B1;5 years). In parallel, thyroid autoantibodies were investigated in blood samples obtained from two separated control groups: age-matched HCV negative-HBV positive patients (25 women, 25 men; mean age= 47&#x00B1;6 years) and healthy blood donors (29 women and 21 men; mean age= 54&#x00B1;8 years). Results: Anti-thyroid antibodies were found more frequently in HCV positive women when compared to the men (8/53= 15.1&#x0025; vs 0/47= 0&#x0025;,.p<0.01).The prevalence of these autoantibodies was not statistically different between HCV positive and healthy female blood donors. However the investigation of thyroid autoantibody titers showed significantly higher levels of anti-TPO and anti-microsomal antibodies in HCV positive women in comparison with healthy women controls (respectively 1: 83200 vs 1: 1900 and 834 vs 23, p<0,01). Conclusions: This strong association between HCV infection and high levels of anti-thyroid autoantibodies in women outlines the interest of systematic detection of anti-microsomal and/or anti-TPO antibodies in this population.

Journal Article↗