Organspezifische Applikation von pharmazeutisch aktiven Substanzen über zellulare Trägersysteme / Organ Specific Application of Drugs by Means of Cellular Capsule Systems

Abstract

It is suggested to use living cells (red blood cells, lymphocytes and leukocytes) as drug delivery systems for temporal and spatial drug administration in human therapeutics and diagnosis. The effectiveness of drug loaded cells is demonstrated for methotrexate which is used in cancer treatment. Red blood cells are loaded with methotrexate using the dielectric breakdown technique. Dielectric breakdown leads to a transient increase of permeability of the cell membrane. Red blood cells loaded with 3H-methotrexate were injected into mice and the activity level was measured in several organs as a function of time. With this drug delivery system more than 50% of the drug (after 10 min) can be accumulated in the liver and a high activity level can be sustained in this organ for more than 3 h. Administration of this drug by injecting solutions in the usual manner only leads to a 25% accumulation of methotrexate (after 10 min) in the liver. The drug is excreted completely after 1-2 h. Red blood cells should be loaded simultaneously with para- or ferromagnetic substances to obtain organ-specificity for any selected body site.