Characterizing Aptamer Interaction with the Oncolytic Virus VV-GMCSF-Lact.

Area of Science:

• Biotechnology
• Molecular Biology
• Virology

Background:

• Aptamers are investigated for improving virotherapy by preventing viral aggregation, enhancing specificity, and offering protection against antibodies.
• Recombinant oncolytic viruses, like VV-GMCSF-Lact, are promising cancer therapeutics but can be affected by serum components and aggregation.

Purpose of the Study:

• To comprehensively investigate an aptamer for enhancing virotherapy, focusing on its interaction with vaccinia virus (VACV) and its potential to protect oncolytic viruses.
• To characterize aptamer NV14t_56, evaluate its binding and aggregation inhibition with VV-GMCSF-Lact, and assess its immunoshielding properties in human blood serum.

Main Methods:

• Selection and optimization of aptamers against vaccinia virus (VACV).
• Characterization of aptamer NV14t_56, including 3D modeling, stability in human blood serum, binding affinity (Kd, EC50) using microscale thermophoresis (MST), and aggregation inhibition via dynamic light scattering (DLS).
• In vitro efficacy testing of the aptamer-virus complex in human blood serum.

Main Results:

• Aptamer NV14t_56 demonstrated high affinity (Kd ≈ 0.35 μM) and stability in human blood serum for 1 hour.
• Dynamic light scattering confirmed aptamers surround viral particles, inhibiting aggregate formation without altering hydrodynamic diameter in serum.
• NV14t_56 effectively bound VV-GMCSF-Lact (EC50 = 1.487 × 10^9 PFU/mL), and serum components did not disrupt the aptamer-virus complex.

Conclusions:

• Aptamer NV14t_56 effectively inhibits virus aggregation and maintains the stability and efficacy of the oncolytic virus VV-GMCSF-Lact in human blood serum.
• NV14t_56 shows potential as a protective agent for oncolytic viruses, though the impact of neutralizing antibodies needs consideration for therapeutic applications.