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

SACERDOTI FLAVIA; ALVAREZ ROMINA; VELEZ DANIEL; REPETTO HORACIO A; IBARRA CRISTINA; AMARAL MARÍA MARTA

Buenos Aires

Congreso; Congreso Conjunto de las Sociedades de Biociencias; 2017

Sociedad Argentina de Investigación Clínica

Typical Hemolytic Uremic Syndrome (HUS) is a systemic complication after Shiga toxin producing Escherichia coli gastrointestinal infection. HUS mainly affects children under 5 years old and it is characterized by kidney and brain damage. Up today no specific clinical marker of this disease has been identified. The aim of the present work was to evaluate the presence of circulating microvesicles bound to Shiga toxin type 2 (MVs-Stx2) in a rat model of sublethalHUS, in attempt to detect a new clinical maker for HUS early diagnostic. For that, Sprague Dawely female rats (180-250 g) were intraperitoneally injected with Stx2 (0.5 ng/g, n=10) or with vehicle: PBS for Controls (n=8). Animals were daily weighted and blood was collected from the tail vein at 0, 48, 72 and 96 h after treatment.Plasma was obtained for creatinine and urea analysis. Plasmasamples were sequentially ultracentrifuged in order to obtain the MVs-enriched suspension. Then, MVs were labeled with Annexin V-FITC and MVs-Stx2 were detected with a mouse monoclonal anti-Stx2 antibody and a secondary antibody labeled with Alexa Fluor 555. MVs were analyzed by flow cytometry. In addition, two days after treatment rats were housed for 24 h in metabolic cages for urine collection and the creatinine clearance (CrCl) was determined. Rats injected with Stx2 had a significant body weight loss at 72 h and 96 h, compared to Controls (P