Strengthened immune responses
Until now, p24-based vaccines have shown limited effectiveness because of an insufficient immune response to this antigen in HIV patients. Based on its Lipidots® delivery platform, CEA's new approach improves immunogenicity against the p24 HIV protein by loading it and an immunostimulant agent onto nanostructured lipid carriers (NLCs). This may be a first step for a new HIV vaccine that also would include additional components of the virus.
"Despite a major effort by the scientific community to develop HIV vaccines, the virus continues to infect people every day," said Fabrice Navarro, head of CEA-Leti's Microfluidic Systems and Bio-Engineering Lab. "Vaccine candidates face immunological obstacles that can be overcome only by introducing innovations in the design of vaccine formulations."
In the article, CEA demonstrated that with mice and non-human primates this new approach significantly enhanced immune responses against p24 by increasing specific antibody production and T-cell activation, when associated with Lipidots NLCs delivering the CpG immunostimulant. Indeed, the lipid carriers are able to protect the CpG nucleic acids from the extracellular environment and to deliver it intracellularly directly into the dendritic cells, the antigen-presenting cells that mediate the induced immune responses.
CEA-Leti's research partners on this study also include IDMIT and IAB-INSERM U1209.