The PLGA-microsphere technology was introduced to the development of drug which is targeting Mycobacterium tuberculosis via phagocytosis of alveolar macrophages. In this paper, the modification and optimization of microsphere/liposome technologies with carbohydrates utilized by the interaction of cell-cell or cell-matrix will be discussed. Carbohydrates present on cell surface, play a role in cell-cell/cell-matrix interactions and regulate cell functions. Macrophage incorporates the pathogens by specific receptors for carbohydrates. These phagocytic receptors are associated with lipid rafts/membrane microdomains and these complexes function as an interface of the cell interacting with foreign bodies. This paper deals with the microsphere/liposome technologies utilizing phagocytic receptors of macrophage and lipid rafts/membrane microdomains.

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Particulate drug carriers have been intensively studied as promising tools of the drug delivery system. In this report, some properties of natural or synthesized phospholipids as materials of liposomes or emulsions were discussed. Experiments using synthesized phospholipids showed that the same phospholipid affected the particle sizes differently between liposomes and emulsions. In liposomes having a bilayer form, the shape and size of the phospholipid molecules mainly caused differences in the particle size. In emulsions in which phospholipids were absorbed at the water-oil interfaces and having a single layer form, in contrast, hydrophilic-lipophilic balance (HLB) was a major factor affecting the particle size. Particle sizes of emulsions prepared with egg yolk lecithin were consistent with results of synthesized phospholipids in case that the lecithin consisted of saturated fatty acid chains. Several analogues of phospholipids, e.g., cationic lipids, arsonolipid, were also reported as materials of liposomes. Some references describing structural difference in these lipids and properties of liposomes were mentioned. Accumulation of expertise in liposomes using phospholipids might afford a clue to discover possible factors affecting generation of liposomes of such analogues.

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