Shiga toxin type 2 (stx2) increases cell volume of human glomerular endothelial cells (HGEC) that express aquaporin 1 and aquaporin 4 (AQP1 and AQP4)

FERNANDO GOMEZ; JULIETA REPETTI; DANIEL CLAUDIO GIRÓN REYES; FLAVIA SACERDOTI; CRISTINA IBARRA; NORA MARTÍNEZ; ALICIA DAMIANO; GISELA DI GIUSTO; MARÍA MARTA AMARAL

Mar del Plata

Congreso; Reunión de Sociedades de Biociencias 2022; 2022

SAIC. SAFIS. SAI-FAIC.

Hemolytic Uremic Syndrome associated to Shiga toxin–producing Escherichia coli (STEC-HUS) infection is the major cause of acute renal injury in pediatric age groups in Argentina. Previously, we demonstrated that Stx2 inhibited the net water transport (Jw) across HGEC monolayers, possibly as a consequence of direct alterations in the Jw mechanisms. In addition, we showed that Stx2 increased the cell area of HGEC and AQPs inhibitors were able to reverse this effect. Therefore, in this work we evaluate changes in cell volume of monolayers of HGEC treated with Stx2 as well as we analyze the expression of both AQP1 and AQP4 by these cells. Immunohistochemical and immunofluorescence studies were performed in HGEC that were grown on gelatinized glass coverslips (12 mm) and then treated or not with Stx2 for 40 minutes. Cell images were acquired and digitized using a confocal microscope Olympus FluoView (FV1000). A z-stack consisting of a series of 0.5 µm optical 2D slices was taken from top to bottom of the cells and then 3D reconstructed. The measure of total cell volume and the analysis of AQP1 or AQP4 expression and localization in HGEC cells images were processed using the Surface tool of Imaris 7.1.0 software. Our results show that HGEC treated with Stx2 exhibited an increase in the cell volume (Stx2: 9374 ± 992 µm3 vs CTRL 4411.15 ± 470 µm3, n=6, p