Brucella abortus-stimulated platelets activate brain microvascular endothelial cells

RODRIGUEZ AM; TROTTA A; MIRAGLIA MC; DELPINO MV; BARRIONUEVO P; GIAMBARTOLOMEI GH

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Central nervous system invasion by bacteria of the genus Brucella results in an inflammatory disorder called neurobrucellosis. Blood-brain barrier activation is a common feature of human neurobrucellosis, but the underlying mechanisms are largely unknown. The aim of this work was to investigate the influence of B. abortus (B.a.)-activated platelets (PTL) on human brain microvascular endothelial cells (HBMEC). For this, supernatants (SN) from B.a.-stimulated human PTL were used to stimulate HBMEC. Expression of ICAM-1 (CD54) and secretion of IL-6, IL-8 and MCP-1 were evaluated to determine HBMEC´ activation. SN from B.a.-stimulated PLT induced a significant secretion of IL-6, IL-8, MCP-1 and the up-regulation of CD54 expression in a dose-dependent manner compared with SN from unstimulated PLT (p0.05), demonstrating that a soluble factor released from PLT was implicated on HBMEC? activation. SN from heat-killed B.a.-stimulated PTL also activated HBMEC indicating that B.a.? viability was not necessary in activating PLT. Soluble CD40L was not implicated on HBMEC? activation, as an anti-CD40L antibody could not block cytokine secretion or ICAM-1 up-regulation. Treatment of SN with trypsin eliminate the effect (p