Endoglin expression level discriminates long-term hematopoietic from short-term clonogenic progenitor cells in the aorta.

CD105 is an auxiliary receptor for the transforming growth factor beta superfamily, highly expressed on proliferating endothelial cells and adult hematopoietic stem cells. Because CD105 mRNA expression was reported in the developing aortic region, we further characterized its expression profile in the aorta and examined the hematopoietic potential of CD105(+) cells. Aortic endothelial cells, intra-aortic hematopoietic cell clusters and the purified cell fraction enriched in progenitor/hematopoietic stem cell activity expressed CD105.

Identification of the pre-T-cell receptor alpha chain in nonmammalian vertebrates challenges the structure-function of the molecule.

In humans and mice, the early development of αβ T cells is controlled by the pre-T-cell receptor α chain (pTα) that is covalently associated with the T-cell receptor β (TCRβ) chain to form the pre-T-cell receptor (pre-TCR) at the thymocyte surface. Pre-TCR functions in a ligand-independent manner through self-oligomerization mediated by pTα. Using in silico and gene synteny-based approaches, we identified the pTα gene (PTCRA) in four sauropsid (three birds and one reptile) genomes.

Dual role of melanoma cell adhesion molecule (MCAM)/CD146 in lymphocyte endothelium interaction: MCAM/CD146 promotes rolling via microvilli induction in lymphocyte and is an endothelial adhesion receptor.

The melanoma cell adhesion molecule (MCAM)/CD146 is expressed as two isoforms differing by their cytoplasmic domain (MCAM long (MCAM-l) and MCAM short (MCAM-s)). MCAM being expressed by endothelial cells and activated T cells, we analyzed its involvement in lymphocyte trafficking. The NK cell line NKL1 was transfected by MCAM isoforms and submitted to adhesion on both the endothelial cell monolayer and recombinant molecules under shear stress.

A dileucine motif targets MCAM-l cell adhesion molecule to the basolateral membrane in MDCK cells.

Melanoma cell adhesion molecule (MCAM), an adhesion molecule belonging to the Ig superfamily, is an endothelial marker and is expressed in different epithelia. MCAM is expressed as two isoforms differing by their cytoplasmic domain: MCAM-l and MCAM-s (long and short). In order to identify the respective role of each MCAM isoform, we analyzed MCAM isoform targeting in polarized epithelial Madin-Darby canine kidney (MDCK) cells using MCAM-GFP chimeras.

Avian HSC emergence, migration, and commitment toward the T cell lineage.

To date three sites of emergence of hemopoietin cells have been identified during early avian development: the yolk sac, the intraaortic clusters and recently the allantois. However, the contributions of the hematopoietic stem cell (HSC) populations generated by these different sites to definitive hematopoiesis and their migration routes are not fully unraveled. Experimental embryology as well as the establishment of the genetic cascades involved in HSC emergence help now to draw a better scheme of these processes.

Melanoma Cell Adhesion Molecule (MCAM) expression in the myogenic lineage during early chick embryonic development.

We describe the expression pattern of cMCAM, a cell adhesion molecule of the immunoglobulin superfamily, in early chick embryonic development by in situ hybridisation. An initial ectodermal domain of expression is subsequently expanded, and cMCAM is expressed in the neural crest cells, otic vesicle, heart primordium, notochord and endoderm. In addition, cMCAM expression localises in the myotome once the somite cells have been specified.