Evaluation of microvesicles containing Shiga toxin type 2 in a rat model of hemolytic uremic syndrome.

ALVAREZ, ROMINA SOLEDAD; IBARRA, CRISTINA; SACERDOTI, FLAVIA; REPETTO, HORACIO A.; VELEZ, DANIEL ALEJANDRO; AMARAL, MARIA MARTA

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Sociedad Argentina de Investigación Clínica

Typical Hemolytic Uremic Syndrome (HUS) is a systemic complicationafter Shiga toxin producing Escherichia coli gastrointestinalinfection. HUS mainly affects children under 5 years old and it ischaracterized by kidney and brain damage. Up today no specificclinical marker of this disease has been identified. The aim of thepresent work was to evaluate the presence of circulating microvesiclesbound to Shiga toxin type 2 (MVs-Stx2) in a rat model of sublethalHUS, in attempt to detect a new clinical maker for HUS earlydiagnostic. For that, Sprague Dawely female rats (180-250 g) wereintraperitoneally injected with Stx2 (0.5 ng/g, n=10) or with vehicle:PBS for Controls (n=8). Animals were daily weighted and blood wascollected from the tail vein at 0, 48, 72 and 96 h after treatment.Plasma was obtained for creatinine and urea analysis. Plasma samples were sequentially ultracentrifuged in order to obtain theMVs-enriched suspension. Then, MVs were labeled with AnnexinV-FITC and MVs-Stx2 were detected with a mouse monoclonal anti-Stx2 antibody and a secondary antibody labeled with Alexa Fluor555. MVs were analyzed by flow cytometry. In addition, two days aftertreatment rats were housed for 24 h in metabolic cages for urinecollection and the creatinine clearance (CrCl) was determined. Ratsinjected with Stx2 had a significant body weight loss at 72 h and 96h, compared to Controls (P