To thwart the progression of emphysema, a lung disease, the Boston University researchers have found a new gene therapy.
Alpha-1 Anti-trypsin Deficiency is the most frequently inherited form of emphysema found in young people due to a mutation in the Alpha-1 Anti-trypsin gene. This genetic disorder makes individuals susceptible to early emphysema and liver cirrhosis.
The team from Boston University School of Medicine (BUSM) experimented on mice and found a way to transport genes selectively to nearly 70 percent of a mouse lung's alveolar macrophages (AM), an important cell contributing to emphysema.
Senior author Darrell Kotton, MD, an associate professor of medicine and pathology and co-director, Center for Regenerative Medicine at BUSM, said: "We applied this novel approach to achieve sustained in vivo expression of normal human alpha-1 antitrypsin (hAAT) protein at levels able to ameliorate emphysema in mice.
"The lung macrophages carrying the therapeutic gene survived in the lungs air sacks for the two-year lifetime of the treated mice following a single intra-tracheal injection of the lentiviral vector we had engineered."
Kotton and his team used this method of gene transfer to get localized secretion of therapeutic levels of human alpha-1 antitrypsin (hAAT) protein in lung epithelial lining fluid.
Andrew Wilson, lead author of the study and an assistant professor of medicine at BUSM, said: "The progression of emphysema in mice exposed to elastase was significantly improved by the gene therapy as evidenced by improvements in lung compliance and alveolar size."
Wilson added: "Our results challenge the dogma that lung macrophages are short-lived and suggest these differentiated cells as a target cell that may be considered for in vivo gene therapy applications including the sustained correction of hAAT deficiency."
The study has been published online in the Journal of Clinical Investigation.