DNA vaccination with all-trans retinoic acid treatment induces long-term survival and elicits specific immune responses requiring CD4+ and CD8+ T-cell activation in an acute promyelocytic leukemia mouse model

Blood. 2010 Jan21;115(3):653-6.
Furugaki K, Pokorna K, Le Pogam C, Aoki M, Reboul M, Bajzik V, Krief P, Janin A, Noguera ME, West R, Charron D, Chomienne C, Pla M, Moins-Teisserenc H, Padua RA.
Blood. 2010 Jan21;115(3):653-6.
La vaccinazione con DNA ricostituito e all-trans retinoico (ATRA) comporta un vantaggio di sopravvivenza in un modello murino di leucemia promielocitica acuta (APL).
ATRA-DNA/leucemia acuta promielocitica.

DNA vaccination and all-trans retinoic acid (ATRA) result in a survival advantage in a mouse model of acute promyelocytic leukemia (APL). Depletion of CD4(+) or CD8(+) cells abolished this effect. CD4(+) depletions of long-term survivors resulted in relapse and death within 3 months, thus demonstrating the need of both CD4(+) and CD8(+) subsets for the generation of DNA-driven antileukemic immune responses and underscoring a crucial role of CD4(+) cells in the maintenance of durable remissions. Degranulation and cytotoxic carboxyfluorescein diacetate succinimidyl ester- based assays showed major histocompatibility complex-restricted APL-specific T cell-mediated immune responses. Sorted APL-specific CD8(+)CD107a(+) T cells showed an increase of antileukemic activity. Effectors from ATRA + DNA-treated mice were shown to secrete interferon- gamma when stimulated with either APL cells or peptides from the promyelocytic leukemia- RARalpha vaccine-derived sequences as detected by ELISpot assays. Our results demonstrate that DNA vaccination with ATRA confers the effective boosting of interferon-gamma-producing and cytotoxic T cells in the leukemic mice.