8] pH-Sensitive immunoliposomes

Abstract

This chapter discusses the use of pH sensitive immunoliposomes. In an effort to design immunoliposomes that can also become fusion active when exposed to a mildly acidic environment, one have developed the pH-sensitive immunoliposomes. The design of the antibody-free, pH sensitive liposomes has been described in detail. Preparation of the pH-sensitive immunoliposomes is described in two steps in this chapter. The procedures for fatty acylation of antibody are discussed first. Incorporation of the fatty acyl antibody into the pH-sensitive liposomes is then described. Characterization of the pH-sensitive immunoliposomes and their interaction with target cells is also presented. In this case, liposome contents are delivered to the lysosomes of the target cells. Whether the contents are degraded or inactivated by the lysosomal hydrolases and whether the contents are released intact from the lysosomes, depends on the nature of the entrapped molecule. In any event, cytoplasmic delivery by pH-sensitive immunoliposomes has greatly increased their carder potential.