DEVELOPMENT AND CHARACTERIZATION OF SOLUPLUS® NANOMICELLES ASSOCIATED TO SPE- CIFIC IgG AS AN INNOVATIVE STRATEGY FOR THE DE- TECTION AND NEUTRALIZATION OF SHIGA TOXIN TYPE 2

GIRON REYES CLAUDIO; GOMEZ FERNANDO D; AMARAL MARÍA MARTA; CHIAPPETTA DIEGO; MORETTON MARCELA; IBARRA CRISTINA; SACERDOTI FLAVIA

Congreso; Reunión de Sociedades de Biociencias.; 2021

Sociedad Argentina de Investigación Clínica

Shiga toxin type 2 (Stx2) is the main virulence factor of Shiga toxinproducing Escherichia coli and is responsible for triggering Hemo-lytic Uremic Syndrome (HUS). We aimed to develop and charac-terize polymeric nanomicelles (PN) with the amphiphilic polymerSoluplus coupled to anti-Stx2 Ig in order to introduce innovativeproposals for the detection of Stx2 and treatment of HUS. PN ofSoluplus were formulated in PBS and coupled with Ig anti Stx2from hyperimmune PN-Ig -Stx2 or control bovine colostrum PN-Ig -Ctrl . The hydrodynamic size of PN, PN-Ig -Stx2 and PN-Ig -Ctrl was evaluated by Dynamic Light Scattering. Morphology of PNor PN-Ig -Stx2 was analyzed by Transmission Electron Microscopy TEM . The PN toxicity was evaluated on both Vero and uman lo-merular Endothelial cells EC and cell viability was determinedby neutral red uptake. After coupling PN with Ig , Stx2 neutralizationcapacity of PN-Ig -Stx2 or PN-Ig -Ctrl was evaluated on Vero and EC cells and the percentage of cell viability was analyzed. Thehydrodynamic size of the PN of Soluplus and Ig -Stx2 showed anaverage diameter of 70.2 ± 1.5 nm and 40.9 ± 2 nm, respectively.When both components were coupled, a single peak with a similarhydrodynamic size of the PN was observed 70.4 0.2 nm . TEManalysis revealed circular particles with a diameter corresponding to100 nm either in PN and PN-Ig -Stx2 particles. PN-Ig -Stx2 wereable to neutralize Stx2 on Vero and EC cells in a dose dependentmanner. hen comparing the neutralization capacity of Stx2 by Ig -Stx2 vs PN-Ig -Stx2 a signi cant improvement in the cell viabilityof Vero and EC was observed with the PN-Ig -Stx2 p 0.001 .The association between anti-Stx2 Ig from bovine colostrum andSoluplus® PN was optimized and characterized. Encouraging re-sults of antibody functionality coupled with PN were registered.These results may open the perspective of the design of new nano-platforms for neutralization and/or detection of Stx2.