The EB66® cell line as a valuable cell substrate for MVA-based vaccines production.

The selection of a cell substrate is a critical step for the development and manufacturing of a viral vaccine candidate. Several parameters such as cell susceptibility and permissiveness to the viral pathogens but also performance in terms of viral antigens quality and production yields are important considerations when identifying the ideal match between a viral vaccine and cell substrate. The modified vaccinia virus Ankara (MVA) is a replication-deficient viral vector that holds great promise as a vaccine platform, however only limited cell substrates have been tested or are available for industrialization.

Undiagnosed leptospirosis cases in naïve and vaccinated dogs: properties of a serological test based on a synthetic peptide derived from Hap1/LipL32 (residues 154-178).

Leptospirosis is a common disease in dogs, despite having current vaccinations. However, leptospirosis diagnosis based on the routine Microscopic Agglutination Test (MAT) leads to confusing conclusions, especially for infected vaccinated dogs. Indeed, both bacterin and natural infection stimulate the production of agglutinating antibodies.

Synthetic peptide issued from Hap1/LipL32 for new early serodiagnosis of human leptospirosis.

Leptospirosis is a worldwide zoonosis. Today, serological diagnosis is generally assessed by MAT. We performed ELISA with a synthetic peptide derived from Hap1/lipL32 which is a protein expressed only by pathogenic Leptospira.

Protection against Leptospira interrogans sensu lato challenge by DNA immunization with the gene encoding hemolysin-associated protein 1.

The use of DNA constructs encoding leptospiral proteins is a promising new approach for vaccination against leptospirosis. In previous work we determined that immunization with hemolysis-associated protein 1 (Hap1) (LipL32) expressed by adenovirus induced significant protection against a virulent Leptospira challenge in gerbils. To avoid the use of the adenovirus vector, we checked for clinical protection against lethal challenge by DNA vaccination.

Structural characterization of the feline-immunodeficiency-virus envelope glycoprotein 36 ectodomain for the development of new antivirals.

In the fight against the human HIV, new targets are being explored, such as the proteins involved in the process of fusion of the virus with the host cell. Recently, the first generation of fusion inhibitors (enfuvirtide), targeting gp41 (virus envelope glycoprotein 41), has become commercially available. However, this promising class of drugs has to be improved in respect of their efficacy and bioavailability.

Identification of the hemolysis-associated protein 1 as a cross-protective immunogen of Leptospira interrogans by adenovirus-mediated vaccination.

New vaccine strategies are needed for the prevention of leptospirosis, a widespread human and animal disease caused by pathogenic leptospires. Our previous work determined that a protein leptospiral extract conferred cross-protection in a gerbil model of leptospirosis. The 31- to 34-kDa protein fraction of Leptospira interrogans serovar autumnalis was shown sufficient for this purpose.

Attempt to modify the immune response developed against FIV gp120 protein by preliminary FIV DNA injection.

Following inactivated virus vaccination trials, the surface glycoprotein gp120 (SU) of the feline immunodeficiency virus (FIV) was considered as one of the determinants for protection. However, several vaccination trials using recombinant Env protein or some Env-derived peptides failed to induce protection. To study the influence of the environment in which the surface protein (SU) is injected.

The disulfide structures of scrambled hirudins.

Scrambled hirudins consist of a collection of equilibrated isomers and serve as essential folding intermediates during the in vitro renaturation of hirudin (Chatrenet, B., and Chang, J.-Y.

The disulfide folding pathway of hirudin elucidated by stop/go folding experiments.

The folding pathway of hirudin was analyzed by structural characterization and stop/go folding experiments of acid-trapped intermediates. The results show that the folding is initiated by a near-random packing, followed by the reorganization and fine adjustment of partially compact intermediates to attain the active molecule. The process of packing is observed as the unfolded hirudin flows sequentially via three groups of equilibrated intermediates, namely one-disulfide, two-disulfide, and three-disulfide (scrambled species) isomers.

Photoactivatable agonist of the nicotinic acetylcholine receptor: potential probe to characterize the structural transitions of the acetylcholine binding site in different states of the receptor.

The nicotinic acetylcholine receptor exhibits at least four different affinity states for agonists such as acetylcholine. In order to identify the structural changes occurring at or near the agonist binding site during the allosteric transitions, three photoactivatable compounds designed to display agonist activity were synthesized. Inhibition constants of these compounds for the cholinergic and the noncompetitive blocker binding sites were determined for the resting and the desensitized states of the receptor.

The folding of hirudin adopts a mechanism of trial and error.

Reduced and denatured hirudin (65 amino acids and 3 disulfides) refolds in vitro to become an active molecule. The folding process adopts a mechanism of "trial and error" without predominant pathways. Throughout the entire folding process, the 6 cysteines were about equally involved in the disulfide shuffling.

Topography of toxin-acetylcholine receptor complexes by using photoactivatable toxin derivatives.

We have defined the molecular environment of a snake neurotoxin interacting with the high- and low-affinity binding sites of the nicotinic acetylcholine receptor (AcChoR). This was done by photocoupling reactions using three toxin derivatives with photoactivatable moieties on Lys-15, Lys-47, and Lys-51. Competition data showed that Lys-47 belongs to the toxin-AcChoR interacting domain whereas the other two residues are excluded from it.