Soluplus® nanomicelles enhance IgG neutralizing properties against Shiga toxin type 2

DANIEL GIRÓN REYES; GABRIELA E. GÓMEZ; JUAN J. CASAL; JOSÉ M. DELFINO; FERNANDO GOMEZ; CRISTINA IBARRA; MARIA MARTA AMARAL; DIEGO CHIAPPETTA; MARCELA MORETTON; FLAVIA SACERDOTI

Mar del Plata

Congreso; REUNIÓN CONJUNTA SAIC SAB AAFE AACYTAL 2023; 2023

SAIC SAB AAFE AACYTAL

Shiga toxin type 2 (Stx2) is the main virulence factor of Shiga toxinproducing Escherichia coli (STEC) and is responsible for the developmentof typical Hemolytic uremic syndrome (HUS). Nowadays,no specific treatment exists for this disease. The aim of this workwas to develop Soluplus® nanomicelles (NM) associated to specificIgG (IgG-Stx2), characterize them, and evaluate their neutralizingcapacity against Stx2 to propose them as a treatment for HUS. IgGStx2or control (IgG-CT) were purified from bovine colostrum byaffinity chromatography. NM-IgG association (NM-IgG-Stx2 or NMIgG-CT) was achieved by the magnetic stirring method. Characterizationof NM-IgG was performed by dynamic light scattering (DLS),UV-Vis, fluorescence, and circular dichroism (CD) spectroscopies,while morphology was analyzed by transmission electron microscopy(TEM). Neutralization capacity of NM, NM-IgG-CT, NM-IgG-Stx2,IgG-CT or IgG-Stx2 against Stx2 was evaluated on Vero cells andHGEC. Additionally, neutralization of supernatants (SN) from STECstrains containing Stx2 was also assayed on Vero cells. NM showeda monomodal size distribution with a hydrodynamic diameter (Dh)of 69.2 ± 0.3 nm, while IgG showed a major Dh peak of 19.3 ± 1.8nm. NM-IgG showed a single peak with a Dh value of 75.1 ± 0.5 nm,significantly higher compared to NM alone (*p