Influence of communication between human renal glomerular endothelial cells and tubular epithelial cells on the action of Subtilase cytotoxin.

ALVAREZ ROMINA; GIRARD MAGALÍ CELESTE; JANCIC, CAROLINA; PATON ADRIENNE W; PATON JAMES C; IBARRA CRISTINA; AMARAL MARÍA MARTA

Boston

Congreso; VTEC 2015; 2015

IntroductionPost diarrhea hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure (ARF) in children in Argentina. It is well established that Shiga toxin type 2 (Stx2) causes direct damage to glomerular endothelial cells and tubular epithelial cells. Recently, it has been reported that Subtilase cytotoxin (SubAB) may be also contribute to the pathogenesis of HUS. Previously, we have reported that Stx2 decreased cell viability and inhibited the water absorption across (Jw) monolayers of human glomerular endothelial cells (HGEC) and human renal epithelial cells (cell line HK-2) in culture. These effects were significantly attenuated on HGEC/HK-2 bilayers. In this work, we studied the SubAB contribution to ARF development and the possible modulation of SubAB effects by endothelium-epithelium communication.MethodsCells were grown on one side (monolayer) or both sides (bilayer) of a permeable support. The epithelial and/or endothelial barrier integrity was established by measuring the transcellular electrical resistance. Cell viability was studied by neutral red uptake. The Jw was determined across monolayers or bilayers placed in a modified Ussing chamber connected to an electro-optical device. IL-6, IL-8 and MCP-1 were quantified by ELISA.Results and DiscussionSubAB (1.5 ug/ml) inhibited the Jw across HGEC (26 %) and HK-2 (22%) after 30 min of incubation, but not across the HGEC/HK-2 bilayers. At later times (72 h), a low dose of SubAB (0.15 ug/ml) caused a reduction of HGEC, HK-2 and HGEC/HK-2 viability. This effect was independent of endothelium?epithelium interaction (HGEC: 67.3 ± 2.6 %; HK-2: 67.4 ± 5.0 %; HGEC/HK-2: 74.2 ± 2.7 % vs Ctrl: 100 %, p