Dendritic cells loaded with HIV-1 p24 proteins adsorbed on surfactant-free anionic PLA nanoparticles induce enhanced cellular immune responses against HIV-1 after vaccination.

Biodegradable nanoparticles with surface adsorbed antigens represent a promising method for in vivo delivery of vaccines targeting a wide range of infectious diseases or cancers. We investigated the feasibility of loading dendritic cells with a vaccine antigen, HIV p24 protein, on the surface of surfactant-free anionic (d,l-lactic acid, PLA) nanoparticles. The p24 protein had a high affinity for the nanoparticles and the antigenicity and immunogenicity of the p24 protein on the nanoparticle was well preserved after immunization.

Generation of specific Th1 and CD8+ T-cell responses by immunization with mouse CD8+ dendritic cells loaded with HIV-1 viral lysate or envelope glycoproteins.

Immunization with antigen-pulsed dendritic cells (DCs) can be used to elicit optimal immune responses. We developed the SRDC cell line, with a morphology, phenotype and activity similar to mouse splenic CD4(-)CD8alpha(+)CD205(+)CD11b(-) dendritic cells, which induce a polarized Th1 immune response. We evaluated the ability of SRDCs pulsed with HIV-1 viral lysate, oligomeric soluble gp140 or capsid p24 to induce specific antibody and T-cell responses in CBA/J mice.

Induction of protective immunity against toxoplasmosis in mice by immunization with Toxoplasma gondii RNA.

Toxoplasma gondii enters the mucosal surfaces of the host, and so immunity at these sites is of major interest. Due to the compartmentalization of the immune response, systemic immunization does not induce high levels of immunity at mucosal surfaces. Intranasal immunization has been shown to be very effective in inducing both systemic and mucosal immune responses.

Toxoplasma gondii antigen-pulsed-dendritic cell-derived exosomes induce a protective immune response against T. gondii infection.

It was previously demonstrated that immunizing mice with spleen dendritic cells (DCs) that had been pulsed ex vivo with Toxoplasma gondii antigens triggers a systemic Th1-biased specific immune response and induces protection against infection. T. gondii can cause severe sequelae in the fetuses of mothers who acquire the infection during pregnancy, as well as life-threatening neuropathy in immunocompromised patients, in particular those with AIDS.

Protective mucosal Th2 immune response against Toxoplasma gondii by murine mesenteric lymph node dendritic cells.

Toxoplasma gondii, an obligate intracellular parasite pathogen which initially invades the intestinal epithelium before disseminating throughout the body, may cause severe sequelae in fetuses and life-threatening neuropathy in immunocompromised patients. Immune protection is usually thought to be performed through a systemic Th1 response; considering the route of parasite entry it is important to study and characterize the local mucosal immune response to T. gondii.