Brucella abortus RNA polarizes macrophages towards a M1 profile at early time points but interferes with M1 polarization at later periods.

TROTTA, ALDANA; BARRIONUEVO, PAULA; AGUSTINA SERAFINO; BALBOA, LUCIANA; JOSE LUIS MARIN FRANCO; M. AYELÉN MILILLO

Congreso; LXVII Reunión Científica Anual de la Sociedad Argentina de Inmunología; 2019

Monocytes and macrophages play a central role in chronic brucellosis. Brucella abortus (Ba) is an intracellular pathogen which survives inside these cells. Macrophages could differentiate from classical to alternative activation. We have showed that Ba RNA and TLR8 ligands promote the secretion of pro-inflammatory cytokines at short periods in macrophages. However, we ignore if these macrophages are polarized through Ba infection. So, firstly we aimed to evaluate if Ba RNA could induce M1 polarization. For this, THP-1 cells or human primary monocytes were differentiated to macrophages and treated with Ba RNA for 24 or 48 h. Then, MHC-II and CD86 were measured by flow cytometry and TNF-α, IL-1β and IL-6 were measured by ELISA. At 24 h, Ba RNA-treated macrophages showed up-regulated MHC-II and CD86 expression and augmented TNF-α, IL-1β and IL-6 secretion (P