Tight junctions Tissue targeting

In cancer treatment, passive targeting of macromolecular carriers to tumors is a commonly used approach. This passive targeting is based on the enhanced permeability and retention (EPR) effect, which leads to an accumulation of the high molecular weight carrier in the tumor tissue. The EPR effect arises from the different physiology of tumor vasculature, where the vessel walls are highly porous and lack the tight junctions that are present in healthy tissue. As a result, macromolecular carriers extravasate and accumulate preferentially in tumor tissue relative to normal tissues [63, 64]. 

Figure 22.3 Epithelial cells can be transfected to therapeutic protein to the basolateral target serve as secreting platform of the therapeutic compartment. This principle of circumventing protein. Protein as such does not permeate the apical tight junctions was demonstrated across the tissue boundary. The nanoparticulates recently in the eye [35]. DNA nanoparticulates that encode the protein also cannot permeate the were administered to the tear side of the cornea epithelial barrier, but they can internalize to the and the transgene product, SEAP, was secreted outermostall layerofthe epithelium. These cells to the anterior chamber of the eye. are transfected and subsequently secrete the...

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