부산대학교 도서관

Pulmonary alveolar proteinosis (PAP) is a lung disease characterised by the accumulation of surfactant, leading to respiratory failure, and premature death. 90 to 95% of PAP cases are caused by the generation of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies. The standard of care is the invasive technique whole lung lavage, which only leads to the temporary remission of symptoms, and which has significant risks. The administration of recombinant GM-CSF also only leads to temporary remission of symptoms and requires repeated administration. The UK Gene Therapy Consortium has developed a pseudotyped lentiviral vector (rSIV.F/HN) that efficiently transduces the lung. In this study, I assessed whether this lentivirus expressing the murine form of the GM-CSF protein (rSIV.F/HN-mGM-CSF lentivirus) can improve the surfactant deposition characteristic of PAP disease, and showed that: (1) In vitro gene transfer leads to dose-related (MOI 0.1, 1, 10, and 100) mGM-CSF expression (median: 0; 290; 6,084; and 3,7322pg/mg respectively; n=6). (2) mGM-CSF produced after lentivirus transduction is functional. (3) Ex vivo human models show significant (mean 230.3pg/ml ±26.8 SEM, n=6) and sustained (seven months) expression of the transgene. (4) Transduction of the lung (1e7 TU/mouse, n=10mice/group) generates significant (p<0.0001) levels of mGM-CSF in bronchoalveolar lavage fluid (treated: median 3,321pg/ml; controls: 0.1pg/ml). (5) mGM-CSF expression after in vivo gene therapy, significantly ameliorates PAP-like disease biomarkers in GM-CSF knockout mice (1e7 TU/mouse, n=15-20mice/group), with significantly decreased bronchoalveolar lavage (BALF) turbidity and surfactant protein D levels (p<0.001). (6) The therapeutic effects are observed early (one-week post-treatment) and maintained for nine months after a single dose of the lentivirus. (7) Low doses of the lentivirus (1e7TU/mouse) are safer than higher doses (25e7TU/mouse). These results provide a proof-of-concept for PAP gene therapy and lay the foundation for the treatment of other diseases caused by the lack of secreted proteins such as alpha-1 antitrypsin deficiency.