DEVELOPMENT AND CHARACTERIZATION OF SOLUPLUS® NANOMICELLES ASSOCIATED TO SPECIFIC IgG AS AN INNOVATIVE STRATEGY FOR THE DETECTION AND NEUTRALIZATION OF SHIGA TOXIN TYPE 2

CLAUDIO DANIEL GIRÓN REYES; FERNANDO GOMEZ; MARÍA MARTA AMARAL; DIEGO CHIAPPETTA; MARCELA MORETTON; FLAVIA SACERDOTTI

Congreso; Reunión Anual de Biociencia 2020; 2021

Shiga toxin type 2 (Stx2) is the main virulence factor of Shiga toxin producing Escherichiacoli and is responsible for triggering Hemolytic Uremic Syndrome (HUS). We aimed todevelop and characterize polymeric nanomicelles (PN) with the amphiphilic polymerSoluplus® coupled to anti-Stx2 IgG in order to introduce innovative proposals for thedetection of Stx2 and treatment of HUS. PN of Soluplus® were formulated in PBS andcoupled with IgG anti Stx2 from hyperimmune (PN-IgG-Stx2) or control bovine colostrum(PN-IgG-Ctrl). The hydrodynamic size of PN, PN-IgG-Stx2 and PN-IgG-Ctrl was evaluated byDynamic Light Scattering. Morphology of PN or PN-IgG-Stx2 was analyzed by TransmissionElectron Microscopy (TEM). The PN toxicity was evaluated on both Vero and HumanGlomerular Endothelial cells (HGEC) and cell viability was determined by neutral red uptake. After coupling PN with IgG, Stx2 neutralization capacity of PN-IgG-Stx2 or PN-IgG-Ctrl was evaluated on Vero and HGEC cells and the percentage of cell viability was analyzed. The hydrodynamic size of the PN of Soluplus® and IgG-Stx2 showed an averagediameter of 70.2 ± 1.5 nm and 40.9 ± 2 nm, respectively. When both components werecoupled, a single peak with a similar hydrodynamic size of the PN was observed (70.4 ± 0.2nm). TEM analysis revealed circular particles with a diameter corresponding to 100 nmeither in PN and PN-IgG-Stx2 particles. PN-IgG-Stx2 were able to neutralize Stx2 on Veroand HGEC cells in a dose dependent manner. When comparing the neutralization capacityof Stx2 by IgG-Stx2 vs PN-IgG-Stx2 a significant improvement in the cell viability of Veroand HGEC was observed with the PN-IgG-Stx2 (p