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

GIRON REYES C.; GOMEZ F.; AMARAL M.; CHIAPPETTA D.A.; MORETTON M.A.; IBARRA C.; SACERDOTI F.

Congreso; REUNIÓN DE SOCIEDADES DE BIOCIENCIAS 2021; 2021

Shiga toxin type 2 (Stx2) is the main virulence factor of Shiga toxin producing Escherichia coli and is responsible for triggering Hemolytic Uremic Syndrome (HUS). We aimed to develop and characterize polymeric nanomicelles (PN) with the amphiphilic polymer Soluplus® coupled to anti-Stx2 IgG in order to introduce innovative proposals for the detection of Stx2 and treatment of HUS. PN of Soluplus® were formulated in PBS and coupled with IgG anti Stx2 from hyperimmune (PN-IgG-Stx2) or control bovine colostrum (PNIgG-Ctrl). The hydrodynamic size of PN, PN-IgG-Stx2 and PN-IgGCtrl was evaluated by Dynamic Light Scattering. Morphology of PN or PN-IgG-Stx2 was analyzed by Transmission Electron Microscopy (TEM). The PN toxicity was evaluated on both Vero and Human Glomerular 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 average diameter of 70.2 ± 1.5 nm and 40.9 ± 2 nm, respectively. When both components were coupled, a single peak with a similar hydrodynamic size of the PN was observed (70.4 ± 0.2 nm). TEM analysis revealed circular particles with a diameter corresponding to 100 nm either in PN and PN-IgG-Stx2 particles. PN-IgG-Stx2 were able to neutralize Stx2 on Vero and HGEC cells in a dose dependent manner. When comparing the neutralization capacity of Stx2 by IgGStx2 vs PN-IgG-Stx2 a significant improvement in the cell viability of Vero and HGEC was observed with the PN-IgG-Stx2 (p