The fusion protein BLS FliC has the capacity to trigger dendritic cells activation in a TLR4 and TLR5 dependant way

ANDRES ROSSI; AGUSTINA ERREA; YANINA HIRIART; MARINA BIEDMA; GRISELDA MORENO; FERNANDO GOLDBAUM; PAULA BERGUER; MARTIN RUMBO

Tours

Simposio; 13th DENDRITIC CELLS SYMPOSIUM; 2014

During the last years there has been increasing research in the vaccines field thathighlighted the need for adjuvant development. TLR agonists are adjuvant candidates based on their capacity to boost adaptive responses. With the aim to develop a new adjuvant system, we have generated a fusion protein combining Lumazine synthase from Brucella spp. (BLS), withTLR4 dependent properties and flagellin (FliC), a TLR5 agonist. We addressed the activation of dendritic cells (DC), an essential step for the induction of the adaptive response elicited by BLS-FliC and studied the contribution of TLR5, TLR4 and MyD88 adaptor protein involved in signaling transduction in BLS-FliC induced DC activation.  Bone marrow dendritic cells (BMDC) were derived from C57BL/6 mice (wt), TLR4-defficient, TLR5-/- or MyD88-/- mice with GM-CSF. Cells were stimulated during 18 h (30µg/ml BLS-FliC). Resulting response was compared with the one elicited by FliC (1µg/ml) and BLS (9µg/ml). BMDC activation was determined measuring the levels of co-stimulatory molecules by flow cytometry and cytokine secretion by ELISA.  BLS-FliC increases the expression of CD80 and CD86 and secretion of IL12p40 and IL-6 on wt BMDC (p< 0.001). Moreover, all measured parameters were higher for BLS-FliC treatment compared to simulation with BLS or FliC as single molecules (p