109. 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 CHIODETTI; FERNANDA SÁNCHEZ-VALLECILLO; FEDERICO DANIEL RUIZ MORENO; SANTIAGO PALMA; GABRIEL MORÓN; DANIEL ALLEMANDI; MARÍA C PISTORESI- PALENCIA; BELKYS A. MALETTO

Mar del Plata

Congreso; LXVI Reunión de la Sociedad Argentina de Inmunología; 2018

Sociedad Argentina de Inmunología

Commonly subunit-based vaccine requires the additionof an adju­vant. To overcome this challenge, new adjuvant strategies are beingdeveloped worldwide in experimental models or in human clinical trials. In thiscontext, we formulated a TLR-9 agonist, CpG-ODN and a model antigen, OVA, witha nanostructure (Coa-ASC16) formed by self-assembly of 6-O-ascorbyl palmitate(OCC). This nanoformu­lation elicited superior adaptive immune responses thansoluble for­mulation of OVA/CpG-ODN (OC). In addition, Coa-ASC16 creates adepot of antigen and CpG-ODN at the injection site. However, de­tails about invivo mechanisms that dictate the priming of vaccine-in­duced immunity arelacking. Here, we investigate the early events in the proximal-draining lymphnodes (LN) of the vaccine injection site. Mice were subcutaneously immunizedwith formulations containing fluorescent-dye labeled OVA and CpG-ODN. Then, theavailability of both molecules contained in the whole LN was measured withOdyssey® CLx at several time points post-immunization (p.i.). In addition, wedetermined, by flow cytometry, the uptake of both mol­ecules from LN bydendritic cells (DC). OVA signal was OC>OCC (p<0.001) and OCC>OC(p<0.0001) at 20 min and 24h p.i. respec­tively; CpG-ODN signal wasOC>OCC (p<0.0001) and OCC>OC (p<0.0001) at 20 min and 24h p.i.respectively. 72 hs after immu­nization, we analyzed single cell suspension ofLN and observed that Coa-ASC16 impacts on antigen uptake, mice immunized with OCCshowed higher numbers of OVA+CD11c+DC, CpG-ODN+C­D11c+DC andOVA+CpG-ODN+CD11c+DC compared with those mice immunized with OC (p<0.001).Conclusion: The nanoformula­tion of vaccine modifies the kinetics of antigenand immunostimulant availability in the LN and improves co-uptake of bothmolecules by DCs despite the fact that our system does not chemically link OVAto CpG-ODN. Understanding of the impact of vaccine formulation on earlyresponse might have a significant impact for rational vaccine design.&amp;amp;amp;amp;amp;amp;lt;!-- /* Font Definitions */ @font-face{font-family:Helvetica;panose-1:0 0 0 0 0 0 0 0 0 0;mso-font-alt:Helvetica;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1342208091 0 0 415 0;}@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:roman;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-alt:Calibri;mso-font-charset:0;mso-generic-font-family:swiss;mso-font-pitch:variable;mso-font-signature:-536859905 -1073697537 9 0 511 0;}@font-face{font-family:"Times New Roman (Cuerpo en alfa";panose-1:2 11 6 4 2 2 2 2 2 4;mso-font-alt:"Times New Roman";mso-font-charset:0;mso-generic-font-family:roman;mso-font-pitch:variable;mso-font-signature:-536859921 -1073711039 9 0 511 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:12.0pt;font-family:Helvetica;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman (Cuerpo en alfa";mso-ansi-language:ES-TRAD;mso-fareast-language:EN-US;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Helvetica;mso-ascii-font-family:Helvetica;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Helvetica;mso-bidi-font-family:"Times New Roman (Cuerpo en alfa";mso-ansi-language:ES-TRAD;mso-fareast-language:EN-US;}size:595.0pt 842.0pt;margin:70.85pt 3.0cm 70.85pt 3.0cm;mso-header-margin:35.4pt;mso-footer-margin:35.4pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}