Philippe Frachet

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The role of talin was addressed by down regulating its expression using an antisense RNA strategy. HeLa cells were transfected with a talin 5' cDNA fragment under the control of the inducible human metallothionein promotor. Isolated clones displayed a decrease in talin level down to 10% of control. The reduction in talin expression dramatically slowed down(More)
The CD9 antigen was described originally as a 24-kDa surface protein of non-T acute lymphoblastic leukemia cells and developing B-lymphocytes. It is also strongly expressed on platelets, among other cells, where it shows the property of mediating platelet activation and aggregation upon binding with mAbs. The primary structure has been elucidated by cloning(More)
Efficient apoptotic cell clearance is critical for maintenance of tissue homeostasis, and to control the immune responses mediated by phagocytes. Little is known about the molecules that contribute "eat me" signals on the apoptotic cell surface. C1q, the recognition unit of the C1 complex of complement, also senses altered structures from self and is a(More)
The classical pathway of complement is an essential component of the human innate immune system involved in the defense against pathogens as well as in the clearance of altered self-components. Activation of this pathway is triggered by C1, a multimolecular complex comprising a recognition protein C1q associated with a catalytic subunit C1s-C1r-C1r-C1s. We(More)
The uptake of apoptotic cells by macrophages and dendritic cells or nonprofessional phagocytes is crucial for development and tissue homeostasis. This is of special importance because deficiencies in the recognition or removal of apoptotic cells may result in autoimmune diseases. The efficient elimination of an apoptotic cell involves contact between the(More)
In the endoplasmic reticulum, calreticulin acts as a chaperone and a Ca(2+)-signalling protein. At the cell surface, it mediates numerous important biological effects. The crystal structure of the human calreticulin globular domain was solved at 1.55 Å resolution. Interactions of the flexible N-terminal extension with the edge of the lectin site are(More)
Platelet membrane glycoprotein (GP) IIbIIIa complex functions as a receptor for fibrinogen, von Willebrand factor and fibronectin, and mediates adhesive reactions of platelets. The gene for the GPIIb subunit is only active in megakaryocytic cell type. We have isolated this gene from a genomic library. The GPIIb gene was characterized by restriction mapping(More)
Platelet glycoprotein (GP) IIb is one of the two subunits of the common platelet adhesion receptor, GPIIb-IIIa. The isolation, characterization and sequencing of cDNA clones encoding for the two polypeptide chains of GPIIb are described. A number of clones were isolated from lambda gt11 libraries constructed with mRNA from an erythroleukemic cell line, HEL,(More)
Using Chinese hamster ovary cell lysate, an in vitro assay has been developed to study the interaction of fibronectin with the alpha 5 beta 1 integrin in a cytosolic environment. In our solid phase assay, 96-well microtiter plates were coated with fibronectin in which cell lysate was incubated. A dose-dependent binding of the fibronectin receptor onto the(More)