Development of dry gene powder for lung and evaluation of its efficacy

Recent y precipitation of powders with supercritical carbon dioxide- (SCF) has been attracting muchattention as a method to produce tarry partides with high functionality我们已经做了报告the gene powders grew cl by the SCF prep bad improved stability and iir aced gene expression in the SCF prep bad improved stability and iir aced gene expression inlungs after intratracheal insufflation in mice. in the present study，我们prepared chitosan-interferon β (DNA) powders by the SCF process to exannne the therapeutics ofthere in murinelung metastasis modelAn bus:solution of pCMV-MuBβ a plasmid DNA cabling murineintern β, and chitosan，一个非viral vector was dispersed in SCF with ethanol as a modifier to precipitate them. Mannitol wasused as a powder vehicle. To establish a lung metasitatis, CT26, mouse colon carcinoma cells，injected intravenously into mouse tail vein. The DNA powder or solution was administeredintratracheally or intravenously to examine the lung weighty, number of metastatic nodules，and survival rate with time. The ge…DNA被保留在normal和normal之间的表达式cancer tissue in the lungwhile no expression was observed in the其他组织. the DNA powders suppressed the increase inlung weight and number of nodules and prolonged the survival of the mice with smaller dose of DNAIntratracheal administration比intravenous administration更有效。These findings suggested that the DNA powders prepared by the SCF processs had high therapeuticpotential in murine lung metastasis model.The next study examined the stability of a gene in powersprepared with supercritical carbon dioxide (CO2) from the viewpoints of the ternary structure of DNAand in vivo inch potential. An aqueous chitosan-pCMV-Luc complex solution containing mannitol wasinjected into the stream of a supercritical CO2/ethanol admixture to precipitate a gene powder. theobtained gem powders and gene solutions placed in stability chambers at 25 or 40 C for 4 weeks。the integrity,and transfection potency of the gene were examined by electrophoresis and in van pulmonarytransfection study in mice The supercritical CO2 process decreased The sided DNA doting Themanufacturing process;however,the decrease in the remaining supercoiled and open circular DNA in the powders during storage wasmuch slower than that in solutions. in additionpowders had W war on potency than the solutions containing the same amount of DNA. the effectof chitosan on the stability of DNA in solutions was not obvious in the solutions but it improvedthe stability of DNA in powders du manufacturing and storage. Thus，a gene powder with a vector is a promising for a ready to use inhalation therapy ofpulmonary diseases. Less

Recent y precipitation of powders with supercritical carbon dioxide- (SCF) has been attracting much attention as a method to produce tarry partides with high functionality We have already reported that the gene powders grew cl by the SCF prep bad improved stability and iir aced gene expression in lungs after intratracheal insufflation in mice. In the present study, we prepared chitosan-interferon β (DNA) powders by the SCF process to exannne the therapeutics of there in murinelung metastasis modelAn bus :solution of pCMV-MuBβ a plasmid DNA cabling murine intern β, and chitosan, a nonviral vector was dispersed in SCF with ethanol as a modifier to precipitate them. Mannitol was used as a powder vehicle. To establish a lung metasitatis, CT26, mouse colon carcinoma cells, were injected intravenously into mouse tail vein. The DNA powder or solution was administered intratracheally or intravenously to examine the lung weighty, number of metastatic nodules, and survival rate with time. The ge … More ne expression after intratracheal administration of DNA was abserved in normal and cancer tissue in the lung, while no expression was observed in the other organs. The DNA powders suppressed the increase in lung weight and number of nodules and prolonged the survival of the mice with smaller dose of DNA than DNA solutions. Intratracheal administration was more effective than intravenous administration. These findings suggested that the DNA powders prepared by the SCF processs had high therapeutic potential in murine lung metastasis model.The next study examined the stability of a gene in powers prepared with supercritical carbon dioxide (CO2) from the viewpoints of the ternary structure of DNA and in vivo inch potential. An aqueous chitosan-pCMV-Luc complex solution containing mannitol was injected into the stream of a supercritical CO2/ethanol admixture to precipitate a gene powder. The obtained gem powders and gene solutions were placed in stability chambers at 25 or 40゜C for 4 weeks. The integrity, and transfection potency of the gene were examined by electrophoresis and in van pulmonary transfection study in mice The supercritical CO2 process decreased the sided DNA doting the manufacturing process; however, the decrease in the remaining supercoiled and open circular DNA in the powders during storage was much slower than that in solutions. In addition, the powders had W war w on potency than the solutions containing the same amount of DNA. The effect of chitosan on the stability of DNA in solutions was not obvious in the solutions but it improved the stability of DNA in powders du manufacturing and storage. Thus, a gene powder with a vector is a promising formulation for a ready-to use inhalation therapy of pulmonary diseases. Less