Faculty of Science and Center of Excellence in Immunology and Immune-mediated Diseases, Chulalongkorn University, Bangkok, Thailand
Title of the talk: Vaccine Delivery System using Nanoparticles
Subunit vaccines such as recombinant protein and DNA vaccine become increasingly important mean to control infectious diseases. For subunit vaccine to effectively induce immunity, vaccine delivery and adjuvants play critical roles. This study investigated the use of nanoparticles, chitosan biopolymer and carbon nanoparticle, for DNA and recombinant protein vaccine delivery against Mycobacterium tuberculosis antigens. For DNA vaccine, chitosan was used to form nanoparticles with a plasmid DNA containing M. tuberculosis gene encoding Ag85B. To enhance an immune response upon DNA vaccination, we co-encapsualted pVITRO-Ag85B with the plasmid containing an mTOR kinase dead construct (pmTOR-KD). Chitosan encapsulated plasmids were then used to immunize BABL/c mice by subcutaneous priming and intranasal boost. After the final boost, sera from mice elicited with a vaccine containing antigen encoding gene and mTOR-KD expressed significant higher Ag85B-specific antibody production than those vaccinated with the pVITRO-Ag85B alone or pVITRO-Ag85B with wild type mTOR. More importantly, highest level of secreted IFN-g and IL-2 were detected in splenocytes restimulated in vitro using recombinant Ag85B from mice immunized using autophagy stimulation condition while IL-4 did not showed any significant difference among all groups. For recombinant subunit vaccine, we used cluster of carbon nanosphere (CCN) prepared from graphene. CCN encapsulated model antigen ovalbumin was readily taken up by cells and the protein was released into cytoplasm. CCN in combination with TLR3 as adjuvant induced significant increase Th1 type cytokine production and cell proliferation. For Taken together, these results nanoparticle delivery system present an effective mean to induce immune response by subunit vaccine.
Tanapat Palaga has completed his PhD in Microbiology/Immunology from University of Massachusetts at Amherst (USA). He was a postdoral fellow at UMass Amherst and a visiting scholar at Max Planck Institute for Infection Biology (Germany). His lab studies cell signaling in immune cells during inflammation and infection and in virus-induced cancer cells. He serves on the administrative board of Allergy, Asthma and Immunology Association of Thailand (AAIAT).