The extradomain A of fibronectin (EDA) combined with poly(I:C) enhances the immune response to HIV-1 p24 protein and the protection against recombinant Listeria monocytogenes-Gag infection in the mouse model.

The development of effective vaccines against HIV-1 infection constitutes one of the major challenges in viral immunology. One of the protein candidates in vaccination against this virus is p24, since it is a conserved HIV antigen that has cytotoxic and helper T cell epitopes as well as B cell epitopes that may jointly confer enhanced protection against infection when used in immunization-challenge approaches. In this context, the adjuvant effect of EDA (used as EDAp24 fusion protein) and poly(I:C), as agonists of TLR4 and TLR3, respectively, was assessed in p24 immunizations using a recombinant Listeria monocytogenes HIV-1 Gag proteins (Lm-Gag, where p24 is the major antigen) for challenge in mice.

Intrinsic order and disorder in the bcl-2 member harakiri: insights into its proapoptotic activity.

Harakiri is a BH3-only member of the Bcl-2 family that localizes in membranes and induces cell death by binding to prosurvival Bcl-x(L) and Bcl-2. The cytosolic domain of Harakiri is largely disorder with residual α-helical conformation according to previous structural studies. As these helical structures could play an important role in Harakiri's function, we have used NMR and circular dichroism to fully characterize them at the residue-atomic level.

Characterization of a novel interaction between Bcl-2 members Diva and Harakiri.

Interactions within proteins of the Bcl-2 family are key in the regulation of apoptosis. The death-inducing members control apoptotic mechanisms partly by antagonizing the prosurvival proteins through heterodimer formation. Structural and biophysical studies on these complexes are providing important clues to understand their function.

Over-expression of peptide deformylase in chloroplasts confers actinonin resistance, but is not a suitable selective marker system for plastid transformation.

Arabidopsis thaliana peptide deformylase PDF1B was expressed in tobacco chloroplasts using spectinomycin as the selective agent. The foreign protein accumulated in chloroplasts (6% of the total soluble protein) and was enzymatically active. Transplastomic plants were evaluated for resistance to the peptide deformylase inhibitor actinonin.

HIV-1 p24-immunoglobulin fusion molecule: a new strategy for plant-based protein production.

We describe the engineering of a human immunodeficiency virus-1 (HIV-1) p24-immunoglobulin A (IgA) antigen-antibody fusion molecule for therapeutic purposes and its enhancing effect on fused antigen expression in tobacco plants. Although many recombinant proteins have been expressed in transgenic plants as vaccine candidates, low levels of expression are a recurring problem. In this paper, using the HIV p24 core antigen as a model vaccine target, we describe a strategy for increasing the yield of a recombinant protein in plants.

Highly immunogenic and protective recombinant vaccine candidate expressed in transgenic plants.

Vaccine development has been hampered by difficulties in developing new and safe adjuvants, so alternative technologies that offer new avenues forward are urgently needed. The goal of this study was to express a monoclonal recombinant immune complex in a transgenic plant. A recombinant protein consisting of a tetanus toxin C fragment-specific monoclonal antibody fused with the tetanus toxin C fragment was designed and expressed.

Antibody processing and engineering in plants, and new strategies for vaccine production.

The use of transgenic plants for the production of recombinant proteins is not a universal solution for all proteins. The choice of this expression system depends very much on the type of protein and its applications. Many proteins will best be made by conventional microbial fermentation, similarly, we are already identifying proteins where plants represent the only practical option for one reason or another.

Rhizosecretion of a monoclonal antibody protein complex from transgenic tobacco roots.

The secretion of a functional, full-length monoclonal antibody complex from transgenic Nicotiana tabacum roots has been demonstrated. Initially, seeds were germinated on nitrocellulose membranes and antibody secretion detected from the developing roots. Plants were then established in hydroponic culture and secretion into the growth medium measured over 25 days.

Transgenic plants expressing antibodies: a model for phytoremediation.

The feasibility of using antibody expressing transgenic plants either to neutralize bioactive molecules in the rhizosphere, or to accumulate and concentrate the molecules in leaves has been demonstrated in a model system consisting of hydroponic Nicotiana plant cultures expressing a murine monoclonal IgG1. Two transgenic plant types were used; in the first, functional antibody was rhizosecreted and shown to bind with antigen in the surrounding medium to form an immune complex. In the second, a transmembrane sequence retained monoclonal antibody in the plants, on the plasma membrane.