Flagellar Surfaces of Parasitic Protozoa and Their Role in Attachment

Abstract

Flagella are thought of primarily as propulsive structures but in the lives of certain parasitic protozoa they have another important role as organelles of attachment to host surfaces. There is now good evidence that such attachment is vital to the survival of the parasite, not simply by anchoring it in a preferred environment, but also by ensuring its transmission to another host. Most practical interest attaches to the pathogenic trypanosomes and leishmanias, as transmission of these important causative agents of major diseases in man and his domestic animals in the tropics and subtropics depends upon flagellar attachment in the insect vector. Prevention of such attachment would, in theory, be a means of controlling the spread of disease. Little is known of the mechanisms operating in flagellar attachment, however, or of the relationship of attachment to parasite morphogenesis. The purpose of this review is to draw attention to an important aspect of parasite cell biology which is now ripe for further investigation.