SIV Vector Pseudotyped with SeV-F/HN Envelope Proteins Produces Long Lasting Expression in the Murine Lung, Is Readministrable and Transfects Human Airway Models.

Griesenbach U, Inoue M, Meng C, Brum AM, Farley R, Newman N, Akiba E, Hasegawa M, Alton EW

Molecular Therapy, Vol 18, S1, Abstract 873

The American Society of Gene and Cell Therapy Annual Conference, Washington DC, 2010

We have previously shown that simian immunodefciency virus pseudotyped with F and HN protein from Sendai virus (F/HN-SIV) transduces murine nasal epithelium effciently (3-5% of respiratory epithelial cells after perfusion with 5x108 TU) and importantly can be repeatedly administered.

We now show that expression in the nasal epithelium persists for the life-time of the animals (16-25 months, 9 of 9 C57Bl/6 mice). The vast majority of published studies have assessed lentiviral vectors in mouse nasal epithelium, and transduction of lung epithelium, particularly without pre-conditioning through polidocanol treatment or tissue damage, remains challenging. Here, we show that F/HN-SIV transduces lung epithelium effciently and dose-dependently.

In contrast to other studies, we show that lentivirus-mediated gene expression in the lung is stable for at least 13 months (latest time-point currently analyzed) (month 2: 362660±63922photons/sec, month 13: 431454±65647photons/sec, n=5-8 mice). We also show, for the frst time, that lentivirus can be repeatedly administered to the lung (2 doses of F/HN-SIV-GFP followed by a 3rd dose of F/HN-SIV-Lux at monthly interval) without loss of activity compared to a single dose of F/HN-SIV-Lux (1 Dose: 40178±4843, 3 Doses: 39080±7490 RLU/mg protein, n=21/ group).

Importantly, we also show that gene expression increases with increasing number of doses (10 doses at daily interval) (Dose 1:4693± 899, Dose 10: 239212±48362 RLU/mg protein, n=8/group, p< 0.0005). Importantly, we have not observed acute or chronic toxicity in 12 months follow-up studies in mice.

We have also assessed the performance of F/HN-SIV in various airway ex vivo models.

  1. The virus transduces human air liquid interface cultures effciently with expression persisting for at least 4 months.
  2. The virus transduces freshly obtained human nasal brushings dose-dependently.
  3. The virus transduces human lung slices effciently and expression persists for the life-span of the slices.

These data suggest that, F/HN-SIV may be a suitable vector for cystic fbrosis gene therapy.