Etude de la réactivité d'allergènes respiratoires vis-à-vis d'acides aminés nucléophiles, du glutathion et d'un peptide modèle

En général, les composés allergisants ont besoin de se lier à des biomolécules pour devenir immunogènes. Ainsi, les sensibilisants cutanés et certains sensibilisants respiratoires doivent réagir avec les protéines épithéliales, en formant une liaison covalente stable, pour donner naissance à un complexe haptène-protéine antigénique. La formation de ce complexe est la première étape indispensable lors de la sensibilisation à des haptènes. Aussi l étude de la réactivité des allergènes cutanés vis-à-vis des protéines a été une cible privilégiée pour le développement de méthodes alternatives à l expérimentation animale. Afin de voir si cette approche pourrait être étendue à des sensibilisants respiratoires (i.e. diisocyanates et anhydrides d acide), notre objectif a été d identifier s il existe une réactivité spécifique de ces allergènes vis-à-vis des acides amines, du glutathion et d un peptide modèle. Une technique développée au laboratoire de Dermatochimie consiste à marquer au carbone 13 les positions réactives des allergènes afin de pouvoir suivre leur réactivité vis-à-vis de biomolécules par RMN. Nous avons montré que l activation du système immunitaire par des molécules conduisant à des allergies cutanées et/ou respiratoires pourrait corréler à un profil de réactivité vis-à-vis des résidus thiol et amine des protéines. Cette observation pourrait permettre de distinguer ces deux catégories d allergènes dans le test alternatif basé sur la mesure de la réactivité peptidique vis-à-vis de peptide comportant un résidu thiol ou amine.Allergens need to bind to biomolecules to become immunogenic. Also, cutaneous and respiratory sensitizers have to react with epithelial proteins, giving rise to the formation of the hapten-protein conjugate through a stable covalent bond. Formation of such conjugate is the first key step during the sensitization process. Reactivity studies of cutaneous allergens towards proteins are one of the main research fields in order to develop alternative methods to animal testing. In order to verify if this approach could be extend to respiratory allergens (i.e. diisocyanates and acid anhydrides), our goal was to identify if it could be possible to distinguish the both type of allergens through their reactivity with amino-acids. A technique has been developed in the Laboratoire de Dermatochimie and consists to label each reactive position of allergens with carbon 13 in order to follow their reactivity towards biomolecules by NMR experiments. It has been shown that the activation of the immune system by cutaneous and/or respiratory allergens could be correlated with their reactivity through the amino or thiol residues. These observations would be allowed to distinguish the both type of allergens in a peptide reactivity assay developed with two peptides containing a thiol or a amino residue.STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF

Novel biobased amines

The present invention relates to a method for producing an amidoamine by reacting a triacid derivative (I) with at least one amine (A), the at least one amine (A) being selected from diethylene triamine and a diamine (II). The molar ratio of the triacid derivative (I) to the at least one amine (A) is in the range of 1 : 2 to 1 : <3. The present invention further relates to the amidoamine as such,and to the use of said amidoamine as a cross-linking agent

Use of glucosamine as shale inhibitor

The present invention is directed to a well fluid comprising at least one oligoglucosamine and/or a salt thereof and a drilling process wherein said well fluid is applied. Further, the present invention is directed to the use of oligoglucosamines and/or salts thereof in the development, exploitation and completion of underground mineral oil and natural gas deposits and in deep wells

Solid-State Self-Assembly of Triazolylpyridine-Based Helicates and Mesocate: Control of the Metal–Metal Distances

Many materials properties are conditioned by the relative arrangement of metal ions in the solid state. Supramolecular architectures such as helicates may be designed with controlled metal to metal spacing in their midst. However, shorter distances and more extensive electronic communication may be achieved between individual architectures through their self-assembly in the solid state. In this manuscript, we report a rational analysis of the solid-state self-organization of dinuclear metallocylinders constructed by octahedral ion coordination with the 1,2,3-triazol-4-ylpyridyl chelate (Fe^II, Ni^II). Overall, aromatic and aliphatic spacers control the range and ranking of metal to metal distances in a predictive manner