Toward Gene Therapy for Cystic Fibrosis Using a Lentivirus Pseudotyped With Sendai Virus Envelopes

Abstract

Gene therapy for cystic fibrosis (CF) is making encouraging progress into clinical trials. However, further improvements in transduction efficiency are desired. To develop a novel gene transfer vector that is improved and truly effective for CF gene therapy, a simian immunodeficiency virus (SIV) was pseudotyped with envelope proteins from Sendai virus (SeV), which is known to efficiently transduce unconditioned airway epithelial cells from the apical side. This novel vector was evaluated in mice in vivo and in vitro directed toward CF gene therapy. Here, we show that (i) we can produce relevant titers of an SIV vector pseudotyped with SeV envelope proteins for in vivo use, (ii) this vector can transduce the respiratory epithelium of the murine nose in vivo at levels that may be relevant for clinical benefit in CF, (iii) this can be achieved in a single formulation, and without the need for preconditioning, (iv) expression can last for 15 months, (v) readministration is feasible, (vi) the vector can transduce human air-liquid interface (ALI) cultures, and (vii) functional CF transmembrane conductance regulator (CFTR) chloride channels can be generated in vitro. Our data suggest that this lentiviral vector may provide a step change in airway transduction efficiency relevant to a clinical programme of gene therapy for CF.

Validation of recombinant Sendai virus in a non-natural host model

“…We have, therefore, recently pseudotyped a simian lentiviral vector with the SeV F and HN proteins (F/HN-SIV) 23 and have shown that the virus efficiently transfects mouse airway epithelium in vivo, as well as human air-liquid interface cultures. 24 Moreover, F/HN-SIV-mediated gene expression persists for more than 17 months after a single administration and repeated administration (3 doses) is feasible. 24 It is interesting that the HN-mediated activation of NK cells does not appear to interfere with F/HN-SIV-mediated gene expression.…”

“…24 Moreover, F/HN-SIV-mediated gene expression persists for more than 17 months after a single administration and repeated administration (3 doses) is feasible. 24 It is interesting that the HN-mediated activation of NK cells does not appear to interfere with F/HN-SIV-mediated gene expression. The F/HN-SIV vector may, therefore, be ideally suited for pulmonary gene therapy.…”

Synchrotron phase-contrast X-ray imaging reveals fluid dosing dynamics for gene transfer into mouse airways

“…This method now enables the rational design of more effective delivery procedures in the airway gene transfer protocols used in normal and CF mouse models. 1,2,14,15 It should also permit improvements in reliability and repeatability to boost outcome effectiveness, reduce outcome variability, and decrease the volumes of costly gene vectors needed in mouse model studies.…”

Cystic Fibrosis Gene Therapy – Not Low-hanging Fruit

“…7 The trial reached its primary endpoint (change in lung function as measured by forced expiratory volume (FEV 1 ) comparing active and placebo (3.7%, Cystic Fibrosis Gene Therapy of persistent expression and efficacy upon repeated administration and are log orders more efficient than the best non-viral formulation. [8][9] Lentiviral vectors have been pseudotyped with various envelope proteins to enable transduction of airway epithelial cells. [8][9] A lentiviral vector pseudotyped with the F and HN proteins from Sendai virus, which has a natural tropism for the airways, is furthest advanced along a translational research path and a first-in-man trial will commence in late 2017.…”

“…[8][9] Lentiviral vectors have been pseudotyped with various envelope proteins to enable transduction of airway epithelial cells. [8][9] A lentiviral vector pseudotyped with the F and HN proteins from Sendai virus, which has a natural tropism for the airways, is furthest advanced along a translational research path and a first-in-man trial will commence in late 2017.…”