Mice deficient in the anti-haemophilic coagulation factor VIII show increased von Willebrand factor plasma levels.

Von Willebrand factor (VWF) is the carrier protein of the anti-haemophilic Factor VIII (FVIII) in plasma. It has been reported that the infusion of FVIII concentrate in haemophilia A patients results in lowered VWF plasma levels. However, the impact of F8-deficiency on VWF plasma levels in F8-/y mice is unresolved.

Gut microbiota regulate hepatic von Willebrand factor synthesis and arterial thrombus formation via Toll-like receptor-2.

The symbiotic gut microbiota play pivotal roles in host physiology and the development of cardiovascular diseases, but the microbiota-triggered pattern recognition signaling mechanisms that impact thrombosis are poorly defined. In this article, we show that germ-free (GF) and Toll-like receptor-2 ()-deficient mice have reduced thrombus growth after carotid artery injury relative to conventionally raised controls. GF and wild-type (WT) mice were indistinguishable, but colonization with microbiota restored a significant difference in thrombus growth between the genotypes.

Gut microbial colonization orchestrates TLR2 expression, signaling and epithelial proliferation in the small intestinal mucosa.

The gut microbiota is an environmental factor that determines renewal of the intestinal epithelium and remodeling of the intestinal mucosa. At present, it is not resolved if components of the gut microbiota can augment innate immune sensing in the intestinal epithelium via the up-regulation of Toll-like receptors (TLRs). Here, we report that colonization of germ-free (GF) Swiss Webster mice with a complex gut microbiota augments expression of TLR2.

Recombinant streptavidin-C3bot for delivery of proteins into macrophages.

We demonstrated previously that monocytes and macrophages are target cells for the Rho-modifying Clostridium botulinum C3 ADP-ribosyltransferase. Here, we report the construction, expression and characterization of a recombinant streptavidin-C3 fusion protein which allows for delivery of biotin-labelled molecules into the cytosol of macrophages via enzymatically inactive C3bot1E174Q. The enzyme domain of diphtheria toxin was used as cargo to demonstrate proof of principle.

Streptavidin-conjugated C3 protein mediates the delivery of mono-biotinylated RNAse A into macrophages.

The C3 toxin produced by Clostridium botulinum (C3bot) catalyzes the mono-ADP-ribosylation of the small GTPases Rho A, B and C, resulting in their inactivation. Recently, a specific endocytotic uptake mechanism of C3bot was identified in macrophages and myeloid leukemia cells. Here, we present a novel delivery system based upon a mutant C3bot devoid of ADP-ribosylation activity (C3Mut) and wild-type streptavidin (Stv).

Internalization of biotinylated compounds into cancer cells is promoted by a molecular Trojan horse based upon core streptavidin and clostridial C2 toxin.

The C2 toxin produced by Clostridium botulinum is a binary AB-type exotoxin composed of the enzyme subunit C2I and the binding/translocation moiety C2II. After proteolytic activation, C2IIa mediates the subsequent internalization of C2I into the cytosol of mammalian target cells. The N-terminal domain of C2I (C2IN) is necessary for C2IIa-dependent uptake, but lacks the enzyme domain that is responsible for cytotoxicity.

Role of CypA and Hsp90 in membrane translocation mediated by anthrax protective antigen.

Bacillus anthracis lethal toxin consists of the protective antigen (PA) and the metalloprotease lethal factor (LF). During cellular uptake PA forms pores in membranes of endosomes, and unfolded LF translocates through the pores into the cytosol. We have investigated whether host cell chaperones facilitate translocation of LF and the fusion protein LF(N)DTA.