Glycosylation vs receptor affinity to improve IFN4N antitumor activity

GUGLIOTTA, AGUSTINA; CEAGLIO, NATALIA; KRATJE, RICARDO; OGGERO, MARCOS

Copenhague

Congreso; 26th Meeting of the European Society for Animal Cell Technology (ESACT); 2019

European Society for Animal Cell Technology (ESACT)

Background and novelty. The antiviral and antitumor activity of interferon-α2b (IFN-α2b) has inspired the development of several new IFN-based drugs. IFN4N is a hyperglycosylated variant developed in our laboratory by glycoengineering. Although this molecule exhibited reduced in vitro bioactivity compared to the non-glycosylated IFN, it showed improved pharmacokinetic properties and higher in vivo antitumor activity. Since R23N mutation has been identified as the main responsible of affecting IFN4N antiproliferative capacity, here we propose the design, production, purification and characterization of new highly glycosylated IFN muteins with better biological activity. Experimental approach. Different groups of muteins were designed and produced in CHO-K1 cells: Group A, IFN variants with the same glycosydic content than IFN4N but higher in vitro antiproliferative activity (by restoring R23 to the molecule); Group B, muteins with higher glycosylation degree but lower in vitro activity (R23 not restored); Group C, muteins with both higher in vitro antiproliferative activity and higher glycosylation degree. Results and discussion. Muteins with higher apparent molecular mass exhibited slower plasmatic clearance in rats. Experiments in nude mice implanted with prostate cancer-derived cells revealed that all new hyperglycosylated variants were able to reduce tumor volume (TV) compared to the vehicle-treated control. Regarding IFN4N, muteins with the same glycosylation degree but with R23N mutation restored (group A) did not significantly decrease TV (p>0.05). Contrarily, muteins from groups B and C caused a reduction of TV in comparison with IFN4N (p