Evaluation of anti-vector immune responses to adenovirus-mediated lung gene therapy and modulation by αCD20

Although the last decade has seen tremendous progress in drugs that treat cystic fibrosis (CF) due to mutations that lead to protein misfolding, there are approximately 8%-10% of subjects with mutations that result in no significant CFTR protein expression demonstrating the need for gene editing or gene replacement with inhaled mRNA or vector-based approaches. A limitation for vector-based approaches is the formation of neutralizing humoral responses. Given that αCD20 has been used to manage post-transplant lymphoproliferative disease in CF subjects with lung transplants, we studied the ability of αCD20 to module both T and B cell responses in the lung to one of the most immunogenic vectors, E1-deleted adenovirus serotype 5. We found that αCD20 significantly blocked luminal antibody responses and efficiently permitted re-dosing. αCD20 had more limited impact on the T cell compartment, but reduced tissue resident memory T cell responses in bronchoalveolar lavage fluid. Taken together, these pre-clinical studies suggest that αCD20 could be re-purposed for lung gene therapy protocols to permit re-dosing.