A Novel Encochleated Formulation Improves Atovaquone Activity in a Murine Model of Pneumocystis Pneumonia.

Although atovaquone is effective in treating and preventing Pneumocystis pneumonia (PCP), its use is limited by nonlinear absorption and adverse events. The current study was undertaken to examine the activity of encochleated atovaquone (eATQ), a novel lipid-crystal nanoparticle formulation, in a mouse model of PCP. eATQ 100-200 mg was superior to commercially available atovaquone at 14 days in decreasing total Pneumocystis nuclei and asci. eATQ plus anidulafungin reduced nuclei significantly better than commercial atovaquone plus anidulafungin. eATQ is a novel formulation of atovaquone that warrants further evaluation for treatment and prevention of PCP.

Efficacy of a nanocochleate-encapsulated 3,5-diaryl-s-triazole derivative in a murine model of graft-versus-host disease.

We have previously demonstrated that the compound 3-(2-ethylphenyl)-5-(3-methoxyphenyl)-1H-1,2,4-triazole exerts immunosuppressive effects in several experimental models of autoimmunity. These results were achieved by subcutaneously administering ST1959 after dissolution in an oily vehicle, because of its poor water solubility. To circumvent this problem, we sought to determine whether nanocochleate technology could be successfully exploited to deliver ST1959 and protect mice undergoing lethal acute graft-versus-host disease (GVHD). Orally-administered encochleated ST1959 significantly protected animals from lethality, resulting in survival rates of 57% and 100% at doses of 2 and 10 mg/kg, respectively, whereas oral administration of 2 mg/kg ST1959, mixed with empty nanocochleates, was completely inactive. Increased survival was associated with diminished serum chemokine levels and donor CD8+ T cells in the spleen of ST1959-treated mice. Moreover, ST1959 treatment significantly counteracted GVHD-induced normocitic anemia by increasing hemoglobin, hematocrit, platelet, and red and white blood cell counts. Overall, these data show that orally-administered encochleated ST1959 significantly protects mice from GVHD.

A novel gene delivery system for mammalian cells.

Although gene therapy holds great promise for the treatment of both acquired and genetic diseases, its development has been limited by practical considerations. Non-viral efficacy of delivery remains quite poor. We are investigating the feasibility of a novel lipid-based delivery system, cochleates, to deliver transgenes to mammalian cells. Rhodamine-labelled empty cochleates were incubated with two cell-lines (4T1 adenocarcinoma and H36.12 macrophage hybridoma) and primary macrophages in vitro and in vivo. Cochleates containing green fluorescent protein (GFP) expression plasmid were incubated with 4T1 adenocarcinoma cells. Cellular uptake of labelled cochleates or transgene GFP expression were visualised with fluorescence microscopy. 4T1 and H36.12 lines showed 39% and 23.1% uptake of rhodamine-cochleates, respectively. Human monocyte-derived macrophages and mouse peritoneal macrophages had 48+/-5.38% and 51.46+/-15.6% uptake of rhodamine-cochleates in vitro. In vivo 25.69+/-0.127% of peritoneal macrophages were rhodamine-positive after intra-peritoneal injection of rhodamine-cochleates. 19.49+/-10.12% of 4T1 cells expressed GFP. Cochleates may therefore be an effective, non-toxic and non-immunogenic method to introduce transgenes in vitro and in vivo.