Magnetic affinity nanoparticles for bevacizumab adsorption

BARREDO VACCHELLI, GABRIELA R.; GIUDICESSI, SILVANA L.; ALBERICIO, FERNANDO; CASCONE, OSVALDO; CAMPERI, SILVIA A.

Simposio; 36th European peptide symposium; 2022

The IgG monoclonal antibody bevacizumab, produced in CHO cells, isused for treating cancer due to its capability of targeting the endothelialgrowth factor A (VEGF-A) and inhibiting angiogenesis. Sold asAvastin, it is on the World Health Organization´s List of EssentialMedicines as one of the safest and most effective medicines in healthsystem. Nowadays, its purification is achieved by protein A affinity chromatography (AC). However, protein A is a very expensive ligandand harsh elution conditions are required to recover bevacizumabfrom the AC column, which can damage the mAb and the proteinA. We have reported that a short peptide contained in VEGF bindsbevacizumab with high affinity and selectivity while immobilized onagarose can be used for bevacizumab purification at lower cost andavoiding harsh elution conditions. However, conventional chromatographyrequires a previous clarification step to avoid clogging the column.On the other hand, the use of magnetic supports is a promisingalternative to conventional methods in downstream processing as targetmaterials can be extracted directly from crude cell lysates in a singlestep by magnetic nanoadsorbents. In this work, bevacizumabpurification with magnetic nanoparticles (MNPs) is assessed.The peptide Ac-PHQGQHIGVSK was synthesized by Fmoc solidphase synthesis on Rink Amide and characterized by MALDS MS. Lyswas incorporated at the C-termini to facilitate its subsequent immobilizationon Pierce NHS-activated magnetic beads.MNPs with the peptide immobilized were added to microtubes with asolution of purified bevacizumab or CHO cell filtrate. The MNPs wereseparated using a magnetic rack and adsorbed protein was eluted.Samples were evaluated by SDS-PAGE, which demonstrated that theMNPs can adsorb bevacizumab selectively.Peptide-MNPs can be useful for bevacizumab purification from culturemedia without prior clarification and for easy sampling for qualitycontrol during the production process.