ABSTRACT
This chapter describes how chlamydiae establish many intimate association, how they maintain themselves once they gain entry into the host, and shows how all of contributes to the remarkable success of the ubiquitious intracellular pathogens. Interactions that have evolved between intracellular pathogens and susceptible host cells are sophisticated, with the attendant compromises and concessions that characterize any long-term relationship between individuals. In ecological terms the parasite is thought of as having evolved specialized adaptations to exploit a particular niche, the inside of eukaryotic host cell, for the purposes of acquiring essential nutrients and perpetuating its own gene pool. Despite the fact that similar adhesins have been identified on the surface of elementary bodies for both Chlamydia psittaci and Chlamydia trachomatis, the host cell ligand and the actual endocytic process may be distinct for each chlamydial species. Once chlamydiae establish intracellular residence within vesicles of the eucaryotic host cell, the process of differentiation begins.
