Search

Your search keyword '"Denizot, Y"' showing total 454 results
Start Over Author "Denizot, Y"
454 results on '"Denizot, Y"'

4. Mouse embryonic stem cell sorting for the generation of transgenic mice by sedimentation field-flow fractionation

Author

Guglielmi, L., Battu, S., Le Bert, M., Faucher, J.L., Cardot, P.J.P., and Denizot, Y.

Subjects
Chemistry
Abstract

Mouse embryonic stem (ES) cells are an important tool for generation of transgenic mice and genetically modified mice. A rapid and efficient separation of ES cells that respects cell integrity, viability, and their developmental potential while also allowing purified ES fraction collection under sterile conditions might be of great interest to facilitate the generation of chimeric animals. In this study, we demonstrated for the first time the effectiveness of a sedimentation field-flow fractionation (SdFFF) cell sorter to provide, with a characteristic DNA content, a purified ES cell fraction and with a high in vivo developmental potential to prepare transgenic mice by generation of chimeras having a high percentage of chimerism.

Published
2004

20. Immunoregulatory functions of paf-acether. IV. Enhancement of IL-1 production by muramyl dipeptide-stimulated monocytes

Author

Salem, P., Deryckx, S., Dulioust, A., Eric Vivier, Denizot, Y., Damais, C., Dinarello, C. A., and Thomas, Y.

Subjects
Immunology, Immunology and Allergy
Abstract

paf-Acether (paf) is a phospholipid mediator of inflammation released from monocytes along with IL-1. In this study, we have examined the role of paf on IL-1 production by human monocytes. When paf from 1 nM to 5 microM, but not its precursor lyso paf, was added to monocytes in the presence of muramyl dipeptide (MDP) or LPS, a marked increase in IL-1 activity over the value with MDP alone was observed. In contrast, paf alone had minimal activity over the same dose range. Antibodies against rHu IL-1 alpha and rHu IL-1 beta neutralized the increased IL-1 activity. Interestingly, MDP that prompts monocytes to synthesize IL-1, induced the synthesis of paf, as well. Most of the paf produced remained cell-associated and always preceded IL-1 synthesis. When the paf receptor antagonist, L-652,731 was added to monocytes, it prevented the enhancement of IL-1 activity induced by exogenous paf. In contrast, L-652,731 had little effect on MDP-induced IL-1 synthesis in the absence of exogenous paf. This may indicate that there are alternative mechanisms involved in the sequences of events leading to IL-1 production. It is also conceivable that the paf receptor antagonist is not able to compete or inhibit endogenous paf as well as it does for exogenous paf. Nevertheless, exogenous paf in association with a second signal, modulates IL-1 production from human monocytes in a positive manner. This may constitute another means through which paf can modulate inflammatory and immune reactions.

Published
1990
Full Text
View/download PDF

21. Flexible long-range loops in the VH gene region of the Igh locus facilitate the generation of a diverse antibody repertoire

Author

Medvedovic, J., Ebert, A., Tagoh, H., Tamir, I.M., Schwickert, T.A., Novatchkova, M., Sun, Q., Huis In 't Veld, P.J., Guo, C., Yoon, H.S., Denizot, Y., Holwerda, S.J., de Laat, W., Cogne, M., Shi, Y., Alt, F.W., Busslinger, M., Medvedovic, J., Ebert, A., Tagoh, H., Tamir, I.M., Schwickert, T.A., Novatchkova, M., Sun, Q., Huis In 't Veld, P.J., Guo, C., Yoon, H.S., Denizot, Y., Holwerda, S.J., de Laat, W., Cogne, M., Shi, Y., Alt, F.W., and Busslinger, M.

Abstract

The immunoglobulin heavy-chain (Igh) locus undergoes large-scale contraction in pro-B cells, which facilitates VH-DJH recombination by juxtaposing distal VH genes next to the DJH-rearranged gene segment in the 3' proximal Igh domain. By using high-resolution mapping of long-range interactions, we demonstrate that local interaction domains established the three-dimensional structure of the extended Igh locus in lymphoid progenitors. In pro-B cells, these local domains engaged in long-range interactions across the Igh locus, which depend on the regulators Pax5, YY1, and CTCF. The large VH gene cluster underwent flexible long-range interactions with the more rigidly structured proximal domain, which probably ensures similar participation of all VH genes in VH-DJH recombination to generate a diverse antibody repertoire. These long-range interactions appear to be an intrinsic feature of the VH gene cluster, because they are still generated upon mutation of the Emu enhancer, IGCR1 insulator, or 3' regulatory region in the proximal Igh domain., The immunoglobulin heavy-chain (Igh) locus undergoes large-scale contraction in pro-B cells, which facilitates VH-DJH recombination by juxtaposing distal VH genes next to the DJH-rearranged gene segment in the 3' proximal Igh domain. By using high-resolution mapping of long-range interactions, we demonstrate that local interaction domains established the three-dimensional structure of the extended Igh locus in lymphoid progenitors. In pro-B cells, these local domains engaged in long-range interactions across the Igh locus, which depend on the regulators Pax5, YY1, and CTCF. The large VH gene cluster underwent flexible long-range interactions with the more rigidly structured proximal domain, which probably ensures similar participation of all VH genes in VH-DJH recombination to generate a diverse antibody repertoire. These long-range interactions appear to be an intrinsic feature of the VH gene cluster, because they are still generated upon mutation of the Emu enhancer, IGCR1 insulator, or 3' regulatory region in the proximal Igh domain.

Published
2013

Catalog

Books, media, physical & digital resources
See catalog results