Study of apoptosis induced by cytostatics and vegetal extracts on human endothelial cell line.

Angiogenesis, the biological process by which new capillaries are formed from pre-existing vessels, is a tightly controlled and complex process involving several factors with both stimulating and inhibiting steps. In solid tumor growth, a specific clinical turning point is the transition to the vascular phase. Once it develops an intrinsic vascular network, a tumor grows indefinitely.

DNA vaccination of neonate piglets in the face of maternal immunity induces humoral memory and protection against a virulent pseudorabies virus challenge.

DNA vaccination represents a unique opportunity to overcome the limitations of conventional vaccine strategy in early life in the face of maternal-derived immunity. We used the model of pseudorabies virus (PRV) infection in pigs to further explore the potential of DNA vaccination in piglets born to sows repeatedly vaccinated with a PRV inactivated vaccine. A single immunisation of 8-week-old piglets with a DNA vaccine expressing secreted forms of PRV gB, gC, and gD, triggered an active serological response, confirming that DNA vaccination can over-ride significant residual maternal-derived immunity.

Vaccination of puppies with a lipid-formulated plasmid vaccine protects against a severe canine distemper virus challenge.

We assessed whether the formulation of a DNA vaccine expressing the canine distemper virus (CDV) hemagglutinin (HA) and fusion (F) immunogens with the cationic lipid DMRIE-DOPE could induce serological responses and protection against a severe CDV challenge in the dog. Although clear protection was observed in dogs vaccinated with formulated plasmids only limited CDV specific antibody titers were observed in protected dogs before challenge, suggesting that protection could be explained by cell-mediated immunity and/or by a strong antibody-based memory response (priming) triggered by the infectious challenge. The high level of protection achieved in this study, demonstrated that formulated DNA CDV vaccines can generate in dogs a level a protection comparable to conventional CDV vaccines.

Immunogenicity of IpaC-hybrid proteins expressed in the Shigella flexneri 2a vaccine candidate SC602.

We have investigated the capacity of live attenuated Shigella flexneri strains to act as vectors for the induction of local and systemic antibody responses against heterologous epitopes. The S. flexneri IpaC antigen was selected as a carrier protein into which the C3 neutralizing epitope of the poliovirus VP1 protein was inserted in eight sites distributed along IpaC.

Functional analysis of the Shigella flexneri IpaC invasin by insertional mutagenesis.

The ability of Shigella to enter epithelial cells, to escape from the phagocytic vacuole, and to induce apoptosis in macrophages requires the IpaB, IpaC, and IpaD proteins. An extracellular complex containing IpaB and IpaC can promote the uptake of inert particles by epithelial cells. To determine whether the function of IpaC is to act as an extracellular chaperone for IpaB in the Ipa complex or as an effector of entry involved in a direct interaction with the cell surface, we have constructed eight IpaC recombinant proteins by inserting the coding sequence for a 12- to 14-amino-acid fragment into restriction sites scattered within the ipaC gene.