Non-invasive liposome-mediated gene delivery can correct the ion transport defect in cystic fibrosis mutant mice.

We report gene transfer to the Edinburgh insertional mutant mouse (cf/cf), delivering CFTR cDNA-liposome complexes into the airways by nebulization. We show full restoration of cAMP related chloride responses in some animals and demonstrate, in the same tissues, human CFTR cDNA expression. Overall, a range of correction was seen with restoration of about 50% of the deficit between wild type mice and untreated cf/cf controls. We report modest correction in the intestinal tract following direct instillation and provide initial encouraging safety data for both the respiratory and intestinal tract following the liposome mediated gene delivery. The non-viral nature and potentially lower immunogenicity of DNA-liposomes suggest that this may offer a therapeutic alternative to adenoviral therapies.

Sendai virus-mediated CFTR gene transfer to the airway epithelium.

The potential for gene therapy to be an effective treatment for cystic fibrosis has been hampered by the limited gene transfer efficiency of current vectors. We have shown that recombinant Sendai virus (SeV) is highly efficient in mediating gene transfer to differentiated airway epithelial cells, because of its capacity to overcome the intra- and extracellular barriers known to limit gene delivery. Here, we have identified a novel method to allow the cystic fibrosis transmembrane conductance regulator (CFTR) cDNA sequence to be inserted within SeV (SeV-CFTR). Following in vitro transduction with SeV-CFTR, a chloride-selective current was observed using whole-cell and single-channel patch-clamp techniques. SeV-CFTR administration to the nasal epithelium of cystic fibrosis (CF) mice (Cftr(G551D) and Cftr(tm1Unc)TgN(FABPCFTR)#Jaw mice) led to partial correction of the CF chloride transport defect. In addition, when compared to a SeV control vector, a higher degree of inflammation and epithelial damage was found in the nasal epithelium of mice treated with SeV-CFTR. Second-generation transmission-incompetent F-deleted SeV-CFTR led to similar correction of the CF chloride transport defect in vivo as first-generation transmission-competent vectors. Further modifications to the vector or the host may make it easier to translate these studies into clinical trials of cystic fibrosis.

Restricted mandibular movement. Report of 2 unusual causes.

Hypomobility of the temporomandibular joint has a variety of causes. Two patients are presented in whom restricted jaw movement was the only clinical manifestation of serious underlying disease. The importance of submitting all tissues removed from patients for histopathological diagnosis is stressed.

Osteomyelitis with proliferative periostitis (Garré's osteomyelitis). Report of a case affecting the mandible.

A case of chronic osteomyelitis with proliferative periostitis of the mandible is reported. This is a unique form of osteomyelitis characterized radiographically by localized thickening of the periosteum and deposition of laminated subperiosteal bone.

Calcifying odontogenic cyst with ameloblastic fibro-odontome: one lesion or two?

The calcifying odontogenic cyst is unusual in that it is frequently found in conjunction with the histologic features of a variety of other odontogenic conditions. Two cases are reported, one of which contained areas histologically similar to the ameloblastic fibro-odontome and also showed condensations of cells in the stroma beneath epithelial strands proliferating from the cyst lining. In both cases the "ghost cells" stained strongly for disulphide groups but only occasional areas were positive for sulphydryl groups. No amyloid or "amyloid-like" material was detected. As no part of the current name is specific to this lesion it is suggested that the nomenclature should be changed--perhaps to "ghost cell dyst".

Laboratory and clinical studies in support of cystic fibrosis gene therapy using pCMV-CFTR-DOTAP.

The first phase I study of cystic fibrosis gene therapy using cationic liposomes to deliver the cystic fibrosis conductance regulator gene to the nose reported partial and transient correction of the nasal transepithelial ion transport defect, While encouraging, further improvements will be required if this form of treatment is to be of therapeutic value. We tested a new formulation, pCMV-CFTR-DOTAP. The complex is stable for 10 days and effective at correcting the electrophysiological deficit in the trachea of CF mutant mice at 8 or 9 days after intratracheal instillation. Reliable protocols for consistent detection of as few as 10 molecules of CFTR mRNA and DNA in nasal brushing samples are described, Both vector and DNA have been produced to Good Manufacturing Practice standard, Nasal potential difference measurements developed at the National Heart and Lung Institute to assess the CFTR ion channel activity in CF patients replicated well at the Scottish Adult Cystic Fibrosis Service. The SPO fluorescence assay for halide ion conductance in nasal brushings has also been tested. These establish baseline conditions in the Scottish CF cohort from which evidence for correction can be judged under clinical trial conditions. These studies formed the basis for regulatory approval of a randomised, placebo controlled double-blind phase I research study.