Dendritic Cells from old mice have a diminished capacity to activate CD8+ T cells

ESTEFANÍA ZACCA; MARÍA INÉS CRESPO; BELKYS A. MALETTO; MARÍA C PISTORESI- PALENCIA.; GABRIEL MORÓN

Viña del Mar, Chile

Congreso; IX Congreso de la Asociación Latinoamericana de Inmunología; 2009

Asoc. Latinoamericana de Inmunología

During aging, B and T cells manifest changes that affect their response to antigens. However, it is practically unkown how dendritic cells could participate in these changes. We have previously observed that dendritic cells from 18/20-month-old mice (old) had a diminished ability to in vivo maturate after LPS injection as well as a lower capacity to cross present in vitro Ovalbumin to a T cell hybridoma, compared to 2-month-old mice (young). Here we found a lower proportion of dendritic cells in spleen and bone marrow of old mice compared to young mice and no differences in liver and peripheral and mesenteric lymph nodes. Splenic dendritic cells from old mice have a lower ability to cross present ex vivo ovalbumin to a T cell hybridoma and to activate in vitro young OT-I T cells, compared to young mice. Finally, splenic dendritic cells from old mice capture in vivo less latex beads than dendritic cells from young mice. These findings show that in the spleen of old mice there is less dendritic cells, which have lower capacity to activate T cells compared to young mice. This deficiency could be related to a lower ability to capture Ag in vivo.