Changes in the availability of vaccine components in draining lymph node are observed when a liquid crystal nanostructure is used as vaccine platform

. CONSTANZA MARIN, ANA LAURA CHIODETTI, MARIA FERNANDA SANCHEZ VALLECILLO, RUIZ MORENO FEDERICO NAHUEL, SANTIAGO DANIEL PALMA GABRIEL MORON DANIEL ALLEMANDI, MARIA CRISTINA PISTORESI PALENCIA, BELKYS ANGELICA MALETTO

Mar del Plata

Congreso; Reunión Conjunta - Sociedad Argentina de Investigación Clínica (SAIC) - Sociedad Argentina de Inmunología (SAI) - Sociedad Argentina de Fisiología (SAFIS); 2018

Commonly subunit-based vaccine requires the addition of an adjuvant. To overcome this challenge, new adjuvant strategies are being developed worldwide in experimental models or in human clinical trials. In this context, we formulated a TLR-9 agonist, CpG-ODN and a model antigen, OVA, with a nanostructure (Coa-ASC16) formed by self-assembly of 6-O-ascorbyl palmitate (OCC). This nanoformulation elicited superior adaptive immune responses than soluble formulation of OVA/CpG-ODN (OC). In addition, Coa-ASC16 creates a depot of antigen and CpG-ODN at the injection site. However, details about in vivo mechanisms that dictate the priming of vaccine-induced immunity are lacking. Here, we investigate the early events in the proximal-draining lymph nodes (LN) of the vaccine injection site. Mice were subcutaneously immunized with formulations containing fluorescent-dye labeled OVA and CpG-ODN. Then, the availability of both molecules contained in the whole LN was measured with Odyssey® CLx at several time points post-immunization (p.i.). In addition, we determined, by flow cytometry, the uptake of both molecules from LN by dendritic cells (DC). OVA signal was OC>OCC (pOC (pOCC (pOC (p