Distribution of a 20-mer phosphorothioate oligonucleotide, CGP69846A (ISIS 5132), into airway leukocytes and epithelial cells following intratracheal delivery to brown-norway rats.
OBJECTIVE
To evaluate the pulmonary distribution of CGP69846A (ISIS 5132), a phosphorothioate oligonucleotide, following intra-tracheal (i.t.) instillation into Brown-Norway rats.


METHODS
The pharmacokinetic profile of [3H]-CGP69846A was investigated following i.t. instillation into both naive and inflamed airways of Brown-Norway rats. The cellular distribution was determined using autoradiography, immunohistochemistry and flow cytometry/fluorescence microscopy, in inflamed airways.


RESULTS
CGP69846A displayed a dose-dependent lung retention following i.t. administration which was unaffected by local inflammation. Autoradiography and immunohistochemistry showed distribution to alveolar macrophages, eosinophils, bronchial and tracheal epithelium and alveolar cells. Studies with [FITC]-CGP69846A demonstrated a preferential association of oligonucleotide with leukocytes in bronchial lavage fluid of: macrophages > eosinophils = neutrophils >> lymphocytes.


CONCLUSIONS
The dose-dependency of lung retention together with cell-specific uptake suggests that the lung can be used as a local target for antisense molecules with potentially minimal systemic effects. Furthermore, the preferential targeting of macrophages and the airway epithelium by oligonucleotides may represent rational cellular targets for antisense therapeutics.
Danahay
H
H
Novartis Horsham Research Centre, Horsham, West Sussex, UK. henry.danahay@pharma.novartis.com
Giddings
J
J
Christian
R A
RA
Moser
H E
HE
Phillips
J A
JA
D000818:Animals; D001345:Autoradiography; D001992:Bronchoalveolar Lavage Fluid; D004847:Epithelial Cells / Q000378:metabolism*; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism; D007150:Immunohistochemistry; D007442:Intubation, Intratracheal; D007962:Leukocytes / Q000378:metabolism*; D008168:Lung / Q000166:cytology / Q000378:metabolism; D008856:Microscopy, Fluorescence; D020319:Oligodeoxyribonucleotides, Antisense / Q000378:metabolism*; D020320:Oligoribonucleotides, Antisense / Q000008:administration & dosage / Q000493:pharmacokinetics*; D051381:Rats; D011914:Rats, Inbred BN; D012137:Respiratory System / Q000166:cytology / Q000378:metabolism; D013056:Spectrophotometry, Ultraviolet; D013873:Thionucleotides / Q000378:metabolism*; D014018:Tissue Distribution
D020319:Oligodeoxyribonucleotides, Antisense; D020320:Oligoribonucleotides, Antisense; D013873:Thionucleotides; C099587:ISIS 5132; D016650:Fluorescein-5-isothiocyanate