Lung disease permeability

Respiratory solute absorption Epithelial permeability <2 xm Interstitial lung disease, lung injury, Pneumocystis carinii pneumonia, adult respiratory distress syndrome... 

In general, when the cells of the endothelium in the lungs are the target cells of interest (see Chapters 7 and 9 on aspects of targeting drugs to endothelium in inflammatory diseases and cancer, respectively), systemic administration seems the route of choice. Bronchial epithelium on the other hand can more easily be reached via the pulmonary route. The accessibility of other cells in the lungs is most hkely governed by disease conditions, factors that can affect epithehal permeability and vascular permeability, and others as described earher. 

Several pharmaceutical and physiological barriers must be overcome for the successful pulmonary delivery of peptide and protein drugs [3], For example, many of these macromolecular drugs have relatively low permeability when they are administered without any absorption enhancers [4], Furthermore, the clinical toxicology of peptides/proteins in the lung, especially for chronic disease, should be of some concern [6], Therefore, cost-benefit ratios should be evaluated in the... 

Tumor targeting Nanospheres facilitate the delivery of a concentrated dose of the drug to the tumor site by permeability enhancement and retention effect or active targeting by ligands on the surface. Selective and controlled drug release to the diseased tissue decreases the toxicity to the nearby healthy tissue. A higher concentration of nanospheres is found in liver, spleen, and lungs than in other parts of body. 

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