Brucella abortus RNA interferes with M1 polarization of human macrophages and diminishes IFN-γ-induced MHC-I molecules on other cells

TROTTA, A; BARRIONUEVO, P; MARIN FRANCO, JL; MILILLO, MA; SERAFINO, AGUSTINA; BALBOA, L

Buenos Aires

Congreso; Reunión Anual de las Sociedades de Biociencias; 2020

Sociedad Argentina de Inmunología (SAI)

Monocytes and macrophages play a central role in chronic brucellosis. Brucella abortus (Ba) is an intracellular pathogen which survives inside these cells. Macrophages could be differentiated into classical or alternative profiles, among others. We have previously showed that Ba RNA (a PAMP associated with bacterial viability or vita-PAMP) activates but does not polarize macrophages per se. Given that B. abortus can survive inside macrophages once a Th1 response is established, we aimed to evaluate if Ba RNA could interfere with M1 polarization. For this, human macrophages were stimulated with Ba RNA under M1 conditions (IFN-γ+LPS) for 24 and 48 h. Ba RNA diminished the (IFN-γ+LPS)-induced MHC-II and CD64 surface expression at 48 h (P